I'm just starting my hot rod Mini project, where I'm mounting a 2L Ford Ecoboost in the rear of a classic Mini, so many of these design and engineering choices will apply to me as well as I also want the car to be livable, so keep the ideas flowing guys!
Now, back to your regularly scheduled posts
MiniDave said:I'm just starting my hot rod Mini project, where I'm mounting a 2L Ford Ecoboost in the rear of a classic Mini, so many of these design and engineering choices will apply to me as well as I also want the car to be livable, so keep the ideas flowing guys!
Now, back to your regularly scheduled posts
You're a man after my own heart. Before deciding to sell it, I was going to do something very similar to a Yugo. I decided to sell the Yugo before I got started on the project because I wanted a "simpler" project. At least the X is already mid engined, so the suspension hard points are already there--and that takes a lot of cipherin' out of the project for me.
After doing some math today, I have realized that the exhaust option involving David Vizard's termination box with two 2.25" pipes exiting the box might be the best way to go. Now I need to determine whether two Dynomax Turbo mufflers would support the CFM needed (440 each) for the zero loss system, or if I would need straight-through mufflers.
I wrote to Mr. Vizard on the subject of the exhaust system to ask for his input. I know that he is very busy, so I am skeptical that we will reply. But maybe, if nothing else, my email will prompt him to make a follow-up to his zero loss sound legal exhaust video. I think that his video is geared toward builders of NA V8 engines.
Below is the text of the email:
Dear Mr. Vizard,
I am aware that you are a very busy man and probably receive many inquiries. I do not mean to impose on your time, but I would appreciate some advice if you are willing to share it.
I have watched your very informative YouTube video on the subject of your zero loss exhaust systems, but I have some questions that are not addressed in the video. The questions are listed below. For the record, I am building a turbocharged four cylinder engine and aiming for 400HP, and would like the exhaust to be as free-flowing as possible while remaining civilized with minimum possible drone. The car is also mid-engined and small (FIAT X1/9,) so total exhaust length and space available to build the exhaust system is not unlimited.
1) You say in the video that the pressure wave termination box needs to be eight times the volume of one cylinder. Is it eight times because you primarily address builders of V8 engines, or would eight times also apply to, say, a four cylinder engine? Does turbocharging affect termination box size since each exhaust pulse will be larger than it would be from the same engine without a turbocharger, or is box size strictly determined by cylinder volume? By the math, a 2L I4 engine would have a termination box of a mere 4L (.5*8,) which seems very small. (I’m imagining a gallon milk jug, 3.8L.)
2) Do all of the zero loss principles apply in the same fashion to a turbocharged engine, or do some principles change, or does your termination box not apply at all to a turbo engine?
3) At one point in the video, you refer to the termination box as a resonator. My understanding is that the purpose of the box is to simulate the end of the exhaust collector pipe, but does the box also serve as a resonator? If it does, is it effective at controlling drone, and are there ways in which a layman can optimize the box for eliminating drone?
4) Are there any performance or resonating advantages or disadvantages to manipulating the proportions of the box, or to placing the outlet pipe(s) on any wall other than the wall opposite the inlet pipe? In my situation, it might be more expeditious from a packaging standpoint to place the inlet and outlet on the same side or on adjacent sides.
5) Would it be harmful to power to direct the wastegate discharge pipe into the termination box?
6) As I have mentioned, eliminating the bassy drone have experienced with large tubing is very important. Your guideline of 2.2CFM per open header horsepower and 115CFM/in2 of tubing suggests that I could build a near zero loss system with dual 2.25” pipes exiting the termination box. A single 3” is also adequate, but would provide slightly less flow than two 2.25” pipes assuming that the mufflers selected flow as well as open pipe. Do you believe that a dual 2.25” system after the termination box would be a quieter option than a single 3”?
7) My understanding is that you had a hand in developing the muffler technology that led to the Walker-Dynomax Super Turbo mufflers. I have used these mufflers on NA engines many times and have always liked the sound. Dynomax advertises “up to 700CFM” on every Turbo muffler on their website. Of course, “up to” means anything from 0-700. I highly doubt that a 2” Turbo muffler flows anywhere near what a 3” Turbo muffler flows. I have written Dynomax for flow numbers on individual Turbo muffler part numbers, but the answer was that they did not have that information. I know that you have flow tested mufflers. Do you believe that I could build a zero loss system with a termination box and parallel 2.25” Turbo mufflers, or would I need something that flows more freely?
8) Last question. This is regarding what the termination box does and why it exists. I understand that a reversion wave starts at the end of the collector (or at the entrance of the termination box) and runs back up the system. What is the effect of sending that wave back up the system close to the head vs at the tailpipe? I assume that the wave is going to happen regardless and cannot be prevented, so I speculate that the wave might be causing backpressure and that giving it a shorter path before it dissipates eases backpressure on the overall system.
MiniDave said:I'm just starting my hot rod Mini project, where I'm mounting a 2L Ford Ecoboost in the rear of a classic Mini, so many of these design and engineering choices will apply to me as well as I also want the car to be livable, so keep the ideas flowing guys!
Now, back to your regularly scheduled posts
A couple of notes regarding your project, or at least insights and decisions/plans from my aborted Yugo project:
1)Mid engine cars seem like they would handle great by nature, but it actually takes a lot of engineering to make them handle well/in a way that doesn't constantly try to kill you. Because I am not an engineer and prefer to build things once and be done, I was going to copy a proven design's geometry. I was looking at MR2 geometry, which would not be difficult to reproduce, and X1/9 geometry, which would be easy to reproduce but required that I inherit the X's expensive ball joints. Both are well-proven rear suspensions. I had settled on X1/9 to simplify the project and keep both ends natively 4*98mm on the hubs. I was planning to keep the Yugo front suspension. Since you are starting with a Mini, you probably aren't interested in saving any of the suspension, and are probably going with a tubular frame on which you will install the body.
2) I was planning to build a tunnel-mounted fuel tank (with an enlarged tunnel, of course) in the way that the MR2s did it in an effort to have *some* front stowage under the hood. I'm pretty sure that I could build a 10 gallon tank, which is enough for the car's purpose. If I were to decide that I couldn't make that work, I would build/buy a front fuel tank as I am doing in the X now.
Thanks for the input!
Did you see the K20 powered X1/9 sold on BaT today for *gasp* $40K!!!!
MiniDave said:Thanks for the input!
Did you see the K20 powered X1/9 sold on BaT today for *gasp* $40K!!!!
I feel like there have been 3 this year (k20 x1/9 on bat) and they all sold for 35-45k!
Edit, I guess only 2, but I really feel like I saw a third one for for 30+ somewhere else too.
I'm also building a k20 powered X. I'm very interested in your ideas, as they are similar to mine. I've purchased the axles and shift cables from Matt, but I'm thinking about doing the motor mounts differently from Midwest. My car isn't going to be as radical as yours, but I'm looking forward to a little more power than the original tired 1300. I'm interested in your shifter, care to elaborate? PM me if you are selling yours as I'm interested. And I'm also interested in your thoughts about the muffler situation, can you elaborate on the sound of the conversions you've done? Also you touched on the brake mods, what changes would you make? I'm going the wilwood way, however I think I'm going to use the Abarth 500 front rotors and wilwood 4 pot calipers at all 4 corners and use different size masters with a balance bar for final balancing. Does midwest use the stock clutch master with the Acura slave, or do they use Acura right through? Sorry for all the questions but you're the man to ask. Cheers, Richard
In reply to Alfagtv6 :
I don't have many answers for you but I'd like to see your build thread!!
Alfagtv6 said:I'm also building a k20 powered X. I'm very interested in your ideas, as they are similar to mine. I've purchased the axles and shift cables from Matt, but I'm thinking about doing the motor mounts differently from Midwest. My car isn't going to be as radical as yours, but I'm looking forward to a little more power than the original tired 1300. I'm interested in your shifter, care to elaborate? PM me if you are selling yours as I'm interested. And I'm also interested in your thoughts about the muffler situation, can you elaborate on the sound of the conversions you've done? Also you touched on the brake mods, what changes would you make? I'm going the wilwood way, however I think I'm going to use the Abarth 500 front rotors and wilwood 4 pot calipers at all 4 corners and use different size masters with a balance bar for final balancing. Does midwest use the stock clutch master with the Acura slave, or do they use Acura right through? Sorry for all the questions but you're the man to ask. Cheers, Richard
I'm happy to answer. I wish I had known ahead of time; I could have named the source for the cables so that you didn't have to pay markup twice. Same with axles.
Regarding axles, now that those are set quantities, it'll be important to get the drivetrain positioning right since the drivetrain location is now constrained by the lengths of those axles and your desire to keep them in the center of their telescoping range.
I am indeed selling the shift linkage. I will PM you.
Exhaust systems:
If you like a sporting sound, you are in luck! Because it is not easy at all to make the system quiet. My advice is this: if you want the exhaust to be polite and sort-of-quiet, and are willing to give up a few HP (the car is still very fast with 10HP missing,) the 2.25" Dynomax turbo muffler is probably the best choice. If you want that 10HP and don't mind a more throaty note, go with the 2.25" straight through such as Magnaflow. All five cars that I built used the Chinese "stainless" header sold on various vendors on eBay. The primaries have to be cut off the flange, and a pie cut is removed to tip the primaries upward enough to clear the rear crossmember but not so much that they interfere with the rear trunk floor. It's not ideal, but I was not allowed to build a vehicle-specific header. I do have to say that I could not *feel* a difference in thrust between the quietest and loudest conversions that I built.
In my time of being away from this thread, I have pretty much decided to build the David Vizard "zero loss" system for the turbo build. This could also be done for your NA build, and the difference is that taking full advantage of the time invested means building a proper header with a tuned collector length. This isn't for everybody, and probably means 40HP tops vs. taking a much easier route. After doing some calculations, I think my system will be 4" off the turbo into Vizard's termination box, then two 2.25" tubes leading to separate 2.25" straight-through mufflers. I haven't yet decided if the wastegate exhaust will flow into the termination box for a quieter exhaust or dump externally for a little rowdiness.
All of the conversions I built used FIAT MCs, both brake and clutch. The clutch pedal throw needs to be increased through shortening the distance between the pedal axis and the pin that pushes back at the MC. Take about 1/2" out of the pedal between those locations. Otherwise, the pedal will be stiff and short and will bottom out the diaphragm before the pedal hits the floor.
For calipers, the Wilwoods are nice and definitely give a better feeling pedal. But I don't think that pedal feel is all that important on a street car. And when calipers lack dust boots, that doesn't sit well with my midwestern mind that is used to driving on nasty, salty roads. My plan is to use OE 500 calipers and make adapters to make them fit. 500 rotors are roughly 10" (good for 14" wheels) and 11" (should be good for 15" wheels) and have the same center bore as the X1/9 hubs. My car will probably use front calipers front and rear. Using front calipers on the rear is a good trick for correcting the X's brake balance, which favors the front too much, but the front calipers have pistons much too large for the 19mm MC.
MiniDave said:Did you see the K20 powered X1/9 sold on BaT today for *gasp* $40K!!!!
One could make a small fortune K swapping X1/9s, as long as he started with a large fortune. A solid, well-sorted K-swapped X at $40k is a good price compared to buying an X and paying somebody to K swap it. Even doing all of your own work, you'll have $20k+ into it if you want a sorted car, plus your own blood, sweat and tears.
As the time to make my first incision draws closer, I am considering other power options apart from K20. The K series engine is fantastic, no doubt about it. The cylinder heads are wonderful. The options are wide open for internal performance parts. The real star to me is the engine management and the access to software such as Hondata, which allow 100% factory drivability on engines that make stratospheric horsepower.
But there are problems, well, mainly one: the cost of buying in in the first place. I am realizing that, for a few reasons, I need to start this project with an inexpensive buy-in in terms of engine and transmission that I can set in the bay and build around. The process of bringing the car to a point of being able to start and run will be at least a year, and during that time I can save and compile and build an engine. What I would really want is a JDM K20A from an Integra Type R. It has some advantages compared to buying a US spec K20A2 package, including factory LSD (saving $1000+ over having to install an aftermarket one.) It has much lower mileage than the US engines that are available these days (200k+ most of the time,) and, compared to the JDM Euro R packages that are more common, it has an ECU for which Hondata offers software, so I don't have to buy another ECU and deal with the pinout differences between Euro R and ITR. SO ANYWAY... The JDM ITR packages are going for $6000 right now if you can find one. I suspect that the transglobal shipping issues have caught up with the JDM engine suppliers. Everybody is out of everything good. That, and/or those engines are now older than JDM TII engines were when they started drying up.
I said all that to say this: there are other options for power in this car that don't require the up-front payout of the K20A--maybe less sizzle than a K20A, but they're out there. In every case, the approximate power goal is 400HP.
Here they are:
K24A2: I'm really saying this one to prevent somebody else from suggesting it. Yes, a K24 is available for a lot less money than a K20A or K20A2. But it doesn't have the same free-revving joy of the K20. Yes, they can be made to sing, but a 99mm stroke means very high piston speeds. Overall, they are a lot less interesting to me than the top line K20A and A2. Buy-in is still $2000+ for engine and trans just to have something to set in the engine bay and start building around. Built engine will pass $6k. This engine would have to be turbocharged to get me to my power goal.
2GR-FE: Fantastic engine from what I have seen. Roughly 300HP in stock form with some tuning. 280 degree cams are available for $1400 plus another $600 for necessary valvetrain parts to allow the cams to work. I could start with a stock engine to get the car running, then later build something nice from a spare engine that I could acquire. A good engine to start with is goin to cost about $1000, but the turbo MR2 transmission that I would want is going to cost another $1500. After port work, cams, engine rebuild, etc., I would probably end up north of $8000 for the engine that I would want. But it *would* make neat Stratos sounds. I am also not sure how well this very wide engine would fit in the narrow X1/9 engine bay, even after cutting.
Honda J series: This one is a bit confusing to me because there are so many iterations of the J series V6 and not a lot of information about which one, or which combination of parts, is best. Engine, figure $500-1000 for something to build around. Trans cost unknown. Building a rowdier engine would end up similar to the 2GR, but with even poorer cam options. Overall, I think that a J series would be a lesser version of the 2GR option above, with an easier fit because of the cylinder head design.
And right below this line are my current leading ideas:
______________________________________________
All my automotive life, I have been a VW guy. Specifically, an 8V VW guy. I have built several 8V engines, each one equally loved for its own special features. I am considering returning to VW engines for this project.
VW 8V Crossflow Turbo: This one has probably the least sizzle of all of the engine options, but it has a few things going for it and is actually my favorite for a number of reasons.
1) Super cheap buy-in, as in I can probably find a bottom end for $200 or so and a trans for around $400.
2) SPA Turbo in Brazil has a nifty new cylinder head for this engine that uses entirely new port geometry designed for performance rather than economy. The new head is turbo-friendly, with greatly improved intake and exhaust ports and an allowance for a much larger exhaust valve than the factory heads would allow. (Turbo engines benefit from a larger exhaust valve relative to a comparable NA engine.)
3) The early VW 8V engines (external water pump engines) were tough as nails with strong blocks and, mostly, with forged crankshafts. Give them some good forged rods and pistons, and they are ready for lots of boost.
4) For all of their "malaise" era shortcomings, they are probably my favorite engine ever. They're what I grew up with in a manner of speaking. I like the simplicity of a SOHC engine with no VVT, no frills. Just two valves per cylinder being flung wide open and gases flowing through heavily worked ports and hand-built manifolds.
5) A relatively crude (compared to the K) engine that has been modified to suit the purpose is actually more in line with the "stradale" idea that I initially laid out for this project. I hate to say that the K is "too refined," but it sort of is. When I think of my inspiration for this project, it's cars such as the Renault R5 Turbo and the Lancia 037. Those homologation specials were lumpy and wild, even in stock form. Their engines were developed into being performance engines, not performance engines from the start. Crude and high-strung, but tough is more in line with the cars that I like so much.
6) Not exactly cheap to build, but not expensive either. Only four pistons, four rods, and eight valves. OE rebuild parts are tough enough for severe duty and still easy to get. I know these engines inside and out, and I know all of the tricks.
7) 02M transmission bolts up, offering a 240mm clutch disc. LSDs are available. They are a tough six speed transmission with some minor faults that can be corrected during a rebuild. Just replace the differential and use BOLTS instead of RIVETS and don't bang the gears hard and they'll be fine.
8) Because of its undersquare design with an iron block that does not need a larger on-center cylinder spacing and because of the 02M's compact two main shaft design, the 8V should package very well into the engine bay, better than the K20. The K20 fits, but it does require clearance work on the left and right sides of the bay. I think that the 8V might need only left side clearancing. Firewall clearance work will still be necessary, and I'd do it even if it weren't strictly necessary to make service easier.
9) I just love the engine, OK?
12V VR6: I am also considering this one. The 12V VR will make 400HP in a foxtrot as long as a turbocharger is present. There are scads of people making 400 turbo horsepower on stock internals. I'm not in love with the VR, and I tend to think of it as the "easy button" solution. The engine itself has always been kinda "meh" to me, but it does have a lot going for it. Virtues and antivirtues in no particular order:
1) I'm going to say this first because it's the first thing that comes to mind with the VR: I HATE the way the timing chain is handled, starting with the fact that it's on the back end of the engine and finishing with the goofiness with which tensioning is managed. I am not stupid, and I am not an inexperienced mechanic, but I struggled to get the cam timing correct on this engine, and somehow, in spite of my care and attention, still screwed it up somehow. This sticks in my craw to this day.
2) Lots of displacement compared to a 2.0L 8V engine means significantly more off-boost power and much lower boost to the power goal.
3) Kinda heavy. It's not that it can't make up for its weight with horsepower. That's not the issue. The issue is that a heavy engine is going into the back of a small, light car and might upset handling in a way that I can't correct.
4) These engines were once prized for swaps and therefore expensive, but, now having been surpassed by several engines, are cheap to buy.
5) Quality cast intake and exhaust manifolds can be had cheap--cheaper than weldable materials for me to build my own.
6) Nice engine sounds.
______________________________________
Engines that I am NOT considering:
VW 1.8T, 2.0 FSI, 24V VR, 07K.
Left-mounted engines such as Honda B and D series, Mitsubishi 4G63, etc. I don't want the engine on the same side as the driver.
Exhaust on front engines such as FIAT 500 Abarth, MINI, Toyota 3SGTE and 4AGE, etc. I don't want a turbocharger on the firewall right behind the passenger.
Please offer up your input regarding engine choices. I am open to suggestions.
I'd encourage you to stick to what you know. K series are truly great, but being familiar with something is great too. I'd say go with whatever gets you what you want out of this project. If you're doing this as an engineering and fabrication exercise, or if you're doing this as a means to the end to have the car you want, you have to choose the engine that supports that project purpose.
Mezzanine said:I'd encourage you to stick to what you know. K series are truly great, but being familiar with something is great too. I'd say go with whatever gets you what you want out of this project. If you're doing this as an engineering and fabrication exercise, or if you're doing this as a means to the end to have the car you want, you have to choose the engine that supports that project purpose.
Thank you. I am doing it for all of the above, really. I do enjoy the journey more than the destination. I do like problem solving. But there's plenty of that to do with any swap. And, although I do enjoy the journey, I also want to get to the destination, and I am realizing that build cost could become a series of obstacles in the road.
The only one thing that makes me hesitate at all regarding the VW 8V option is engine management. The Hondata is SO nice. Drivability is like factory. My experience with SEM is very limited. I don't mind paying a skilled tuner to tune the ECU for me. I just want to know that drivability would at least be similar to factory, taking into account the limitations of the engine, i.e. low compression and big cam. All of my 8VT tuning experience has been on CIS, which has always worked out well on small turbochargers and up to about 200WHP. But we are going well beyond that here.
Does anybody reading this have first hand experience with getting good drivability out of SEM?
As you'd probably expect, I suggest checking out the 2.0L Ecotecs. They meet your specs (engine on the passenger's side, exhaust out the back) but they're fairly wide, maybe even wider than the K20. If you want any measurements, let me know. The heads aren't as good as the K series but you can still delete the balance shafts, port the head, and rev the nuts off em if you want to.
The earlier port-injected supercharged ones (LSJ) can be found for around ~$1k. No VVT on those. There's a decent aftermarket out there for turbocharging them and they are good for 400HP. The later VVT direct-injected turbocharged ones (LNF, LDK, LHU) can be found for <$2k.
What about the SRT4/ PT GT 2.4?
-Engine and manifold orientation is correct.
-Already a turbo engine with internals capable of your stated power goals.
-Factory LSD transaxle options
-Affordable and available
-Possibly tunable with a controller on factory pcm? (I am not an expert, but have seen diablosport etc. )
There is someone here who has started the PTGT swap into an X.
In reply to obsolete :
I have also seen YouTube videos of using the Saab ecotec(LK9?) basically already a turbo LSJ, the recipe seems to be use a wiring harness and ecu from the cobalt SS (so you can tune with hp tuners)
You can find whole donor Saab 9-3s for pretty cheap, I think some came with lsd as well.
Looks like the Saab 2.0 just engines close to me on car-part.com range from $265-$600
In reply to Somebeach (Forum Supporter) :
Oh yeah, I forgot about the Saab engines. Good info.
GasTungstenArc said:The only one thing that makes me hesitate at all regarding the VW 8V option is engine management. The Hondata is SO nice. Drivability is like factory. My experience with SEM is very limited. I don't mind paying a skilled tuner to tune the ECU for me. I just want to know that drivability would at least be similar to factory, taking into account the limitations of the engine, i.e. low compression and big cam. All of my 8VT tuning experience has been on CIS, which has always worked out well on small turbochargers and up to about 200WHP. But we are going well beyond that here.
Does anybody reading this have first hand experience with getting good drivability out of SEM?
A project like this will cost a lot in all the little things, so planning to save on the big things (engines) should definitely help keep you moving. Regarding drivability and SEM, I can only speak to my own experience. Choosing an ECU is tricky because people get too wrapped up in chasing features instead of focusing on the tuning software. You say Hondata is nice, but I know at least two people that were nothing but frustrated by attempting to tune it. I don't offer that data point to counter your experience but only to show that you have to look at these things from what you want out of it. If you're set on building a heavily cammed, boosted engine, then you've got an uphill battle to make it drivable with a random standalone ECU. You are making tradeoffs with cams and big boost that are usually paid for in NVH and drivablity. I've got a 1.3 NA engine with high compression and ITBs that behaves like a factory car in most conditions. Cold start needs some work still. Transient loads and response off of cruise is not as smooth as it could be...but it always starts and goes as expected. Your configuration is far more complex to tune but still something you can do with a little patience and maybe some classes.
You said you're in this project for all the parts...getting a running and driving car that needs some tuning is a hell of a lot better than a car that's stalled because you can't afford a motor. But what about a running driving car that's tuned well with a tame engine while you save up and collect the parts to make a beast? That might be a good avenue.
I think the SAAB/Ecotec engine option is worth a hard look.
Mezzanine said:GasTungstenArc said:The only one thing that makes me hesitate at all regarding the VW 8V option is engine management. The Hondata is SO nice. Drivability is like factory. My experience with SEM is very limited. I don't mind paying a skilled tuner to tune the ECU for me. I just want to know that drivability would at least be similar to factory, taking into account the limitations of the engine, i.e. low compression and big cam. All of my 8VT tuning experience has been on CIS, which has always worked out well on small turbochargers and up to about 200WHP. But we are going well beyond that here.
Does anybody reading this have first hand experience with getting good drivability out of SEM?
A project like this will cost a lot in all the little things, so planning to save on the big things (engines) should definitely help keep you moving. Regarding drivability and SEM, I can only speak to my own experience. Choosing an ECU is tricky because people get too wrapped up in chasing features instead of focusing on the tuning software. You say Hondata is nice, but I know at least two people that were nothing but frustrated by attempting to tune it. I don't offer that data point to counter your experience but only to show that you have to look at these things from what you want out of it. If you're set on building a heavily cammed, boosted engine, then you've got an uphill battle to make it drivable with a random standalone ECU. You are making tradeoffs with cams and big boost that are usually paid for in NVH and drivablity. I've got a 1.3 NA engine with high compression and ITBs that behaves like a factory car in most conditions. Cold start needs some work still. Transient loads and response off of cruise is not as smooth as it could be...but it always starts and goes as expected. Your configuration is far more complex to tune but still something you can do with a little patience and maybe some classes.
You said you're in this project for all the parts...getting a running and driving car that needs some tuning is a hell of a lot better than a car that's stalled because you can't afford a motor. But what about a running driving car that's tuned well with a tame engine while you save up and collect the parts to make a beast? That might be a good avenue.
I think the SAAB/Ecotec engine option is worth a hard look.
All good points, and good recommendations from all. I will look into the mentioned engines.
Regarding starting with a tame engine and building something wild later, it's a good suggestion--especially if the tame engine and the wild engine are externally the same. If I stick with my VW 8V idea, that becomes more difficult. I don't mind making minor changes around a built engine that I would install later, but the VW option wouldn't work like that. If I am using the SPA head, the manifold faces are entirely different from any OE VW head. That means new manifolds on both sides, and that's more rework than I want to do. And because the head comes unfinished, i.e. no valves or valvetrain and ports that were intended to be worked, I would be confronted with a large machining payout on the tame engine, and some hard choices to make: do I just build the tame engine's head to be wild and transfer it later to a built bottom end, or pay twice for two differently developed heads? The bulk of the expense is in the head, so that leads me to want to build the bottom end and be done with it...
The reality is that the build will take long enough that as long as I keep pressure on the engine builder, the engine will be done by the time I actually need it. I don't even mind buying a second head (only $400) to install with two head bolts on an engine block in order to be able to build everything that goes around the engine before I actually need a running engine. It's going to take me at least a year worth of spare time to build the car to that point.
As for management, you are correct that I am starting the race with one foot in a bucket by having a big cam. I don't expect the same drivability out of such an engine as I would out of a stock engine. I have had good drivability in the past out of 8V engines with 280 degree (advertised) and .450" cams. What I need is a car that starts without a lot of protest, idles stably (not necessarily smoothly, but not hunting or trying to stall,) maintains an appropriate AFM during transitional throttle and cruise, and returns the power I want under full load. I don't expect factory smoothness. I just don't want a cantankerous bitch that has cold and/or hot starting issues and bucks and snorts when I'm just trying to drive to work without boiling the tires.
My ONLY hands-on experience with SEM was SDS more than 20 years ago. Because of the cam duration on that engine (280,) SDS recommended a non-MAP fuel system. The lack of MAP or air flow sensing made fuel tuning very difficult for everything short of WOT. I dearly wish I hadn't listened to them regarding MAP. Tuning a non-MAP system is not typical of the SEM tuning experience for most people, but it's the only experience I have.
Hmm. I've spent more time thinking about your quandary than I usually do on other people's projects. If it were me, I think I'd go the K-swap route. We all know it fits, we know it meets your power goals. Get a cheaper K24 to build it out and maybe drive a while until you source/build the K20A you want. The more I think about this path, the more right I think it is IF you're willing to stay naturally aspirated. If you are going boost, I'd go ecotec. We know others have done the swap in an X (there's one here on the forum), and there's loads of great factory options to support this direction that make me think you could do it for less total $$ invested than a boosted K swap option.
Thanks for the clarification on your drivability standards: I believe those can easily* be met with modern engine management and software.
*easily in this case still demands a fair bit of education on engine tuning and familiarity with your tuning suite.
I'm failing to find the ecotec swapped X I mentioned above, but did find this one: Custom Chassis Ecotec X1/9
Can anyone help me find the other? I recall it was fairly deep-end, but not a custom chassis.
Mezzanine said:I'm failing to find the ecotec swapped X I mentioned above, but did find this one: Custom Chassis Ecotec X1/9
Can anyone help me find the other? I recall it was fairly deep-end, but not a custom chassis.
I appreciate your investment of time.
The Ecotec guy has popped up on XWeb from time to time. I have seen the tube frame car also.
I don't see me sticking with NA power on any I4, even though the K can make a fair amount of it. Turbochargers do some things that I have come to appreciate, including building torque and suppressing exhaust noise. For me to commit to go NA, I would need a lot more displacement--2.8L VR minimum or 3.5L 2GR-FE. There are things to like and to hate about both of those engines. I am curious how well either one would fit lengthwise in an X1/9 considering how tight the K20 package is. Engine width is easier to deal with because things like firewall and rear upper crossmember are more negotiable datums than strut towers and frame rails.
But I don't think it's time to talk about big engines just yet. I think I would rather keep it to turbo I4 engines at this point.
obsolete said:As you'd probably expect, I suggest checking out the 2.0L Ecotecs. They meet your specs (engine on the passenger's side, exhaust out the back) but they're fairly wide, maybe even wider than the K20. If you want any measurements, let me know. The heads aren't as good as the K series but you can still delete the balance shafts, port the head, and rev the nuts off em if you want to.
I'll have a look. Delete the balance shaft AND rev them hard? Wait, shaftS, plural? Those two things seem contradictory to me. If they don't need the balance shaft(s) to stay together, why are they there?
In reply to GasTungstenArc :
Yep, dual balance shafts just like a K, except instead of down by the oil pump, they are on the sides of the block. They counteract the inherent up and down shaking of an inline 4 and are strictly an NVH thing, nothing to do with the balance of the rotating assembly.
Here's something else to ponder that I haven't seen mentioned up to this point--how heavy/grabby of a clutch are you comfortable with to hold that 400hp?
You'll need to log in to post.
