In reply to AAZCD-Jon (Forum Supporter) :
To make your plan even more complicated (but maybe simpler in the end, I hope?) here's another fun fact:
The "N+W+F upgrade" is a big brake swap for the Beretta (and Corsica, I guess?) using all factory parts. N-body aluminum spindle, W-body rotor, F-body caliper. Somebody else came up with it, we did it on our Beretta for LeMons 10 years ago, it worked great. I'm sure you don't want massive brakes on the rear of your Fiero, but here's the part that might apply to you...
The N-body outer CVs have larger diameter splined ends to fit in the larger N-body hubs (sound familiar?), but the splines on the outer ends of both the L-body and N-body axle shafts themselves are the same. So, the key to making the N-body spindle work on the L-body Beretta was swapping the outer CV joints between axles. L-body inner CV, L-body axle shaft, and N-body outer CV makes an axle that's the right length with the right splines on both ends for all the parts to bolt together.
So, whatever combination of transmission, spindles, and track width you want, you can probably assemble hybrid axles that will make it work. You may even be able to find an off-the-shelf axle from another GM application that will just work. There's some nice CV axle interchange info floating around on this forum somewhere, I'll see if I can find it...
In reply to obsolete :
Cool stuff. Not sure that I'll need more brake, but I love to see what parts can be interchanged and combined.
In reply to AngryCorvair & AnthonyGS :
I was incorrect in my previous post about how it can add to a car that's maxed out in budget. Here's the two threads that I had read and mis-remembered:
trading-labor-for-challenge-fodder-no-longer-in-rules
just-another-tradebudget-question
In reply to AAZCD-Jon (Forum Supporter) :
it's kinda funny to me that I used the Chinesium turbueno example in that other thread 2 years ago, and again earlier today without any memory of the thread from 2 years ago.
In reply to AngryCorvair (Forum Supporter) :
That does make more sense, but it's still pretty grey. I bet no one on year one, two or three had this kind of entry. It's a sliding scale that allows the cars to get faster and faster and stay in budget.
I haven't had any significant progress other than measuring things and looking through my junk pile. I may change course away from the 3.5L and go with the much simpler 3.8L swap.
The more I looked at the idea of extending control arms, the more I realized it was not a good solution. The way the transmission sits, one axle will fit as-is and the other axle is about 2-1/2 inches too long - it is not an equal space difference on both sides. So, if I extend one control arm to make the axle fit, the geometry gets pretty weird. Mixing the Fiero axles with the Buick drivetrain is not practical.
Possible ways forward with the 3.5L would be:
- Transmission swap
- Fabricated cradle
- Fabricated axle or find one stock that fits.
I just found a car with a 3800 series II (I think) that would keep in budget range for the Challenge. As much as I like the idea of going with the newer tech LX9 drivetrain, I don't want to ruin the car trying to make it work. As I've said, all of my knowledge of swaps is based on 1990s and 2000s German cars and Hondas. The specifics of GM cars from nomenclature to layout is all new material for me. As I go forward I am likely to hit dead ends and change course. That's not bad. It's how I learn. Playing around in the $2,000 budget arena I can afford to make a few mistakes. Will I buy the Grand Prix? ...maybe. I need to do some study tonight.
In reply to AAZCD-Jon (Forum Supporter) :
I think the more documented 3800 swap would be best for your circumstances.
In reply to AAZCD-Jon (Forum Supporter) :
I vote fabricated cradle, or modification of current cradles. You have your hard targets defined, just a matter of connecting the dots with metal. It's probably easier than you think.
Patrick
MegaDork
2/10/22 11:49 a.m.
I agree with indy guy, also the 3800 is quite heavier
Which one will be fastest? You should go with that one.
You guys got me thinking again. I'm going to look at: using the Buick wheel carriers and axles with the Fiero control arms on a widened Fiero cradle.
Using the Buick axles keeps the engine/trans centered and track width equal on both sides of the car. The Fiero arms will fit well if both sides of the cradle are shifted about an inch outward and both wheels should have manageable negative camber on the wider track.
...but I already told the guy with the $800 2001 Grand Prix GTP that I'd look at it today. If it starts up and sounds decent, I should make a low-ball offer and bring it home ...for Science.
A quick look at CV axles on RA also opens other possible benefits of having the Grand Prix. The right axle looks like it's about the correct length for what i wanted. Not sure if the joints will swap out or need to be swapped. Rock Auto can be really handy for getting detailed specs. Worth a look.
Ok... of course I bought the Grand Prix. Of course it was a mistake and distraction that I don't need.
It had been listed for about four months starting at $1,000. The ad said that the transmission was bad and the engine was good.
When I got there the seller said that just after he changed the transmission filter and fluid, he was driving it and the transmission completely quit. Would not move. He towed it home and it has sat since. He was sure that it has a bad band and didn't have money to fix or replace the transmission.
I brought a battery and it started right up. Oil looks good. Only bad noise is the PS pump. Smoke from leaky valve cover gaskets. I hadn't expected it to start so easily or run so smoothly.
I put it in reverse and felt it engage. In drive there was a slight engagement, but clearly not enough to move the car.
I offered my top dollar price, $600 and he didn't hesitate to accept. That's $300 for the engine and $300 for the rest of the car, agreed and on paper. I could have bargained better, but the 'kid' can use the money more than me.
The problem I have now is that the transmission works just well enough that I want to troubleshoot it and see if I can fix it before I take the car apart. I backed it off the trailer under it's own power, no problem. It took some coaxing to get it to drive forward, but it did. I can drive the car around my yard as long as I'm patient about driving forward. I put my Autel scanner on the OBD port and it didn't even power up. A fuse or wiring is bad. Judging by where it was parked there's a high probability that rodents have had access to the wiring. I'll try to just take a day or two playing around with it before getting back to the Fiero.
I got $125 for the last one of those superchargers I sold and I'm sure they've gone up in price since then...
obsolete said:
I'm kind of surprised that the engine mounting is so different. Stuff must have changed between the 3400 and 3500. When we swapped out the 2.8L in an '89 Beretta with a 3400 from an '99 Alero for LeMons, 2 of the 3 mounts bolted right on. The other one needed to be fabricated.
There are two main styles of the GM 60*v6. RWD/iron head, and then FWD with aluminum heads.
The iron head style was the original 2.8 introduced in the X-body, and used in the fiero, and fbody until 95 (2.8/3.1/3.4).
Then there is the later FWD aluminum head engines (3100/3400/3500/3500vvt/3900). The latter two are further different from the former 3. But there are quite a number of differences in accessories, oil pans, engine mounts, pistons....
Most fiero swaps to newer v6's did modified the fiero subframe to take the newer v6, and played games with timing covers, accessories, etc.
That's a good deal for a supercharged engine donor. Is this a direct bolt-in swap for the Fiero engine? You can keep your Fiero trans/subframe/suspension?
maschinenbau said:
That's a good deal for a supercharged engine donor. Is this a direct bolt-in swap for the Fiero engine? You can keep your Fiero trans/subframe/suspension?
The 3800 SC is not quite a direct swap, but pretty close. It is highly documented and 'so easy a cave man could do it'. The Fiero subframe and suspension work, but it uses the 4T65E-HD transmission rather than the Fiero transmission which is not rated for the power.
The Buick/3.5L donor has the 4T65E (non-HD) transmission which is basically the same except for the TC, Diff, and gearing. It looks like the axles from the Grand Prix are exactly what I need to make the correct axle to swap the 3.5L onto the stock Fiero cradle. ...I'm just reading through all this tonight, but it seems that my swap just got a lot simpler to go forward with the 3.5L engine.
There's so much info on the web that it gets hard to sort through but here's a couple places I started and moved on from:
- https://www.fastfieros.com/3800faq.htm
- https://www.fastfieros.com/tech/4t65e_transmission_general.htm
- https://www.fiero.nl/forum/Forum2/HTML/139530.html
- https://3800wiki.com/transmissions/4t65e
Also 'Eric Jon'/EJS262 gave me some info in my thread on the Fiero Forum and will probably feed me more info if I reach out for help.
My biggest problem isn't that the information isn't out there. It's more that life keeps pulling my focus in many different directions. ...Oh and I think I'm going to cut the back end off the Grand Prix and make it into a trailer for my Gambler 500 rig. ...if I use the LX9 in the Fiero, what should I put the 3800 SC into..? Clutch quit on Mrs AAZCD's Element - Just had to flush and bleed. Helping my 'pretty much son in law' put a motorcycle engine together tomorrow and Grandkids all coming over Sunday. ETC.
I need a few Full Afternoons to make progress. Thirty minutes at a time just makes a mess.
I spent some time with the Grand Prix today. The OBD port came to life after I replaced the Cig Lighter fuse. No DTCs and electric indications of gear selection, input shift speed, and solenoids looked good as far as I can tell.
That's enough to satisfy me that I don't want to mess with it until after I make significant progress on the Fiero. For now, all I need from the Grand Prix is the right front axle. I'll pull that soon.
Top priority now is getting a parts car Boxster in shape for North Texas Rallycross in early March. When the very short 'manual transmission' axle I ordered for the Fiero arrives, I'll get back to it.
The axle arrived today and looks perfect. I'd get to work on it, but I'm leaving town in a couple hours and won't be back until Sunday. Monday - Tuesday I should make some good progress on the car.
I made some progress on Monday - Tuesday and nothing since. The Grand Prix axle was fairly easy to pull and I replaced it with the aftermarket axle from the Buick Rendezvous. The whole Buick is on the budget, so I'm thinking it's a direct trade; used good axle from Buick for used good axle from Grand Prix.
Reading the various builds people have done, there are different combinations of axles used for pretty much the same thing. I think that what will work best for me is the left manual transmission axle combined with the end from right the Grand Prix axle. If it turns out that I want it a little longer I can use the shaft from the left side Grand Prix axle.
The axle is assembled and engine laid on the cradle. The next big thing is making mounts for the engine and transmission to sit properly. Rallycross in a week with the sCrappy Boxster along with the Mint 100 is going to keep me busy 'till then. Hopefully I can find a few hours to work on the mounts.
Here's a little update. Today I test fitted the slightly modified cradle in the car. It fit most of the way as I lifted it into place, but I still need to remove the alternator bracket from the engine to get it in properly - the top edge of it bumps the shock tower. I have it out of the car now and will be finish-welding the engine mount brackets that are currently tacked onto the cradle. There is very little play or choice in where the engine mounts. It sits down in the cradle with about a half inch of clearance at most. As it sits there, the axles look like they will fit just right. All of the metal that I used was cut from the Buick cradle.
Axles... It turns out that I was wrong. The info that I read about the 3800 SC swap was good, but I am not (so far) using the HD transmission - I'm using the transmission from the Buick. When I tried to fit the modified axle into the transmission it wouldn't fit and the axle from the Buick that I put in the Grand Prix would not engage with the transmission. There's about a 3mm difference in the size of the shaft. It turns out that the stock manual transmission axle as delivered was correct for the non-HD transmission.
I made a big mistake. When I stripped the electronics and chassis harness out of the Buick, I put it in a big plastic tub and left it outside. The car had a serious roach infestation and I didn't want to take a chance of infesting my garage and house. It turned out that the brand new tub was not completely weather tight and when I opened it recently to check on the stuff there was plenty of water in the bottom. The ECU has been safe and dry, stored in the Fiero, but all the relays, fuses, and some modules were in that tub. I have cleaned and dried them. They *look* like they are all still good with no corrosion, but some of it had been soaking for a couple weeks. I'll find out if there's a problem after everything is installed in the car. I'm not going to worry any more about it until then.
Stampie
MegaDork
3/14/22 11:03 p.m.
In reply to AAZCD-Jon (Forum Supporter) :
Contact cleaner being a liquid would be budget exempt for the Challenge. Just saying.
-
Fluids (including gasoline, oil and brake fluid). Nitrous oxide refills do not count toward the budget (however, the cost of the equipment that comes along with a nitrous setup does need to be added to the budget).
-
Nominal amounts of grease (such as what’s required to pack bearings) do not need to be included in the budget.
ejs262
New Reader
3/15/22 5:37 a.m.
AAZCD-Jon (Forum Supporter) said:
Also 'Eric Jon'/EJS262 gave me some info in my thread on the Fiero Forum and will probably feed me more info if I reach out for help.
I here that Eric guy is a real a-hole, watch out... lol. I just updated my thread and started looking around and saw another fiero on the front page and figured I'd take a look, just to find my name in said thread! lol.
Personally, I like the 60 degree engines better than the 90 degree, especially in a light car, the 3800's can be pretty stout too though. the LX9 has the same mount bosses on the block as the factory 2.8, and IIRC, you could put the timing cover and accessories from your 87 2.8 on your LX9 with some minor triming of the timing cover and drilling or plugging a hole. doing that would let you bolt the engine in, which takes half of the mounts out of the equation. That being said, the Fiero accessory drive is trash compared to the LX9. using stock fiero mounts does require some trimming though.
The Lx9 uses an LS1(V8) style trigger wheel, it may be possible to run it off of a 0411 LS1 PCM, but I haven't done it, so I can't confirm that, however, I have run it with a 3400 style PCM (with a 3400 OSID and an external crank sensor), a 3800 PCM (on a 3800 OSID also with the external crank sensor) and a MS3. running any of the above non factory PCM's will allow way more room for tuning, as there is (was?) no support for the factory LX9 PCM, and all should support your current transmission as well.
The G6 LX9 manifolds are generally considered the best to get from a performance standpoint, you may be able to get a set of stockers damn near free if you're looking for a cheap upgrade.
The LX9 crank sensor is hall effect, and contains an electromagnet, over time, the sensor can (will) accumulate ferrous wear products/contaminants that will eventually cause the crank sensor signal to obscure and cause the engine to not run cleanly at mid-high RPM, I would guess that it could eventually cause the engine not to run. I would recommend pulling the sensor and checking it now while it's easy to access.
I look forward to the next round of updates. if I can help, feel free to ask.
AAZCD wrote:
The whole Buick is on the budget, so I'm thinking it's a direct trade; used good axle from Buick for used good axle from Grand Prix.
Correct. zero hit to bottom line, zero hit to recoup.
I extended the platform for the engine mount on this part of the cradle to adjust it for where the LX9 mount sits.
After welding it in place, I drilled two holes where I thought the mount should be placed. ...then made the hole into slots to get it where it should actually be placed. A couple of washers on the nuts and it won't even care.
On the other side I used a cutting from the Buick cradle to make a flat spot, then tacked the cut off mount and base from the Buick onto it. Testing the engine position the first time, it was angled wrong and off by about 1/2". I ground it off and tacked it back on.
The second test fit well. Keep in mind, that I do not have great skills at any of this and rather than making a precision cardboard model to plan with, I'm working with the engine dangling from a hoist - it spins and tips as I try to place it, one hand lowering the boom while I stretch out a foot to stabilize the load dropping onto the cradle.
Then this happened this evening. It probably has nothing to do with the 'Challenge Car', but could come in handy for parts as I continue stewardship of the 'Milburn Fiero'.
Planning to pick it up tomorrow afternoon. After looking it over to figure out what it is, I'll probably seal it up and leave it alone for a few months.
