300 hp V6s are all the rage!

In reply to Keith Tanner:

Keith you come a very blessed position to speak from.

Knurled wrote: The point is, why need more? When you find yourself having to lift because you're encountering tirespin at 80mph, *and you are towing a nose heavy trailer*, maybe it is time to re-evaluate how much power you think you want.

Or it's time re-evaluate your suspension or tires. Yes, there's a point of more power than you can use, but if 300hp is leading to 80mph wheelspin, I'd say it's not an issue of too much power, but one of a chassis that hasn't been optimized well enough to be able to use that power.

Knurled wrote: The point is, why need more? When you find yourself having to lift because you're encountering tirespin at 80mph, *and you are towing a nose heavy trailer*, maybe it is time to re-evaluate how much power you think you want.

That just means you need more traction. I can easily put down more than 300 hp at 80 mph without extra weight on the rear tires. If you can never, ever use 300 hp you've got problems. This IS a motorsport forum, right?

In reply to Keith Tanner:

It's true that I was talking about driving on public roads. Motorsports, as you're aware, happen on unpaved roads and you can't put more than about 250hp down through two wheels on dirt/gravel.

I heard that some people actually try to race on paved tracks. That sounds kinda dull. It's like, the same course every lap. What fun is that?

You can't put down over 250 HP on dirt? hmmmm. I never have any problem with that wheeling my Xterra all over west Texas with 2wd and a good diff and tires. J/K I know what you are trying to say.

Seriously, Owning a good V6 car in my G and then now putting almost 2K miles on Betty in over a week. It's a whole different world. I can see the attraction to both. It's the difference between quick and truly fast though.

yupididit wrote: I was looking at v6's that are NA to put in my Conquest. The LS plus t56 = lots of cutting. And I'm not interested in doing an LS at all.

3.8 Mivec from the 4th gen Eclipse? That could probably get 300 without needing boost.

That would be really cool. Unfortunately, 6g7* engines don't have rwd options. Not any that make them worth trying. There's a conquest with a 6g72 swap with a th400 that was attached using a very custom setup made by bill hincher. It made about 800hp on megasquirt.

Oh i should have finished the thread before i messaged you about mitsu v6s, i suppose. There ARE rare 6g RWD manual transmissions, and autos are downright plentiful. For 3.0-3.8L worth of na torque, i would just adapter plate to what's in there and not worry about it! Starions already make that torque anyway.

Let's build it!

Is this from Tifosi Performance?

I don't know and he doesn't know. He's not a car guy and he just gave it to the shop who did it all and then gave him a dyno sheet.

I'm willing to bet the aluminum LS's weigh less than some v6's though lol.

An aluminum V6 weighs more than an aluminum V8?

Vigo wrote: Oh i should have finished the thread before i messaged you about mitsu v6s, i suppose. There ARE rare 6g RWD manual transmissions, and autos are downright plentiful. For 3.0-3.8L worth of na torque, i would just adapter plate to what's in there and not worry about it! Starions already make that torque anyway. Let's build it!

Haha I'm not sure the 6g75 bolts up to the starion rwd trans. I do have an spare 88 trans though!

carguy123 wrote:

I'm willing to bet the aluminum LS's weigh less than some v6's though lol.

An aluminum V6 weighs more than an aluminum V8?

I said aluminium ls probably weighs less than SOME v6's. I didn't state if the v6's were aluminum or not.

carguy123 wrote:

I'm willing to bet the aluminum LS's weigh less than some v6's though lol.

An aluminum V6 weighs more than an aluminum V8?

Some V6s. They're not all aluminum. Many of the current ones have big complex heads with a stack of camshafts. And some have turbochargers on them It's a very, very gross generalization, but the LS series of engines is popular in large part because it's so power-dense.

Keith Tanner wrote: For a given power/torque level, I'm not sure an LS is more weight. You'll need the same transmission strength. You'd also need turbos on that V6, which introduces more weight, more volume and more heat management. When you're into the boost, it'll drink like a V8 because it takes fuel to make power. Now, if you're saying you don't want the power and torque of an LS, then of course you'll have savings throughout the build because you don't need the strength.

No, the thread is about the non-tubo'd V6s of 300 hp. I mentioned the twin turbo V6 of Ford just cause I got to drive a couple over the weekend. In a heavy car they would be nice, but as an engine swap in an older, lighter car or a Locost you don't need more than 300 hp.

There are so many applications that 300 hp is the sweet spot.

I got to drive a friend's V8 Locost. 351 4bbl, not a particularly stout build.

I wondered if I wanted a V8 and I quickly found I did not. Don't get me wrong, it was fun, but not as much fun as the basically the same car with a Honda S2000 motor, and actually quite a bit slower than the Honda.

It took a lot more consumables which made racing it quite a bit more expensive. He was having to run 18-20" wide Formula Atlantic tires on all 4 corners to keep it planted which made it cost way more and made it fell a bit numb when compared to the Honda car.

It took a lot more in brakes, gas and other consumables. So much so that auto crossing it became expensive enough it doesn't get used as often.

And then there's the transmission! To me the transmission makes or breaks the car. It's your main contact with the driveline and the transmission you have to use on the V8 is quite a bit clunkier than the trans on a S2000 or Miata.

Most of the V8 Locost people just stick it in a gear and "let the torque carry you through". You can do that, but it's not as fun or as fast as an engine and tranny that lets you use the engine to it's full potential. If I'm going to have to spend the amount of money it takes to keep a V8 monster in tiresome etc. then by golly I want to be one of the fastest guys out there.

Look at the speeds of those little SAE race cars the universities make. They don't look like much but they let you take advantage of everything you've got.

The weight of the V8s make cornering & braking slower than the lighter more nimble cars.

yupididit wrote: 3.6 Chevy v6 Is this deal typical?

It seems to be very typical, although a little on the higher end of the scale from what I've been seeing.

Now tell me how to make it work in something else? I have 2 somethings that would benefit from one of those.

I'm willing to bet the aluminum LS's weigh less than some v6's though lol.

An aluminum V6 weighs more than an aluminum V8?

I said aluminium ls probably weighs less than SOME v6's. I didn't state if the v6's were aluminum or not.

The 300 hp V6s from the big 3 are all aluminum including heads

In reply to carguy123:

Yeah, but outside of the new 4.3L from GM, they're all DOHC which requires very wide cylinder heads. I'd bet the amount of aluminum that goes into casting a cylinder head for an LS engine is about the same as the amount of aluminum that goes into a v6 DOHC head. The LS head casting might even be lighter than the DOHC V6 casting. And of course there are 4 cams (instead of 1), all of the heavy VVT stuff (4 times as much), more timing chain/guides (for each cylinder bank), 4 valves per cylinder (vs 2), etc. The bottom end of the LS will probably be heavier, but the top end of the V6 will probably be heavier than the v8. And if you're designing an optimal swap engine, it's not going to have huge cylinder heads that take up lots of space and raise the CoG.

This is all just internet speculation, and we really don't know unless we could compare fully built engines side-by-side. Of course you're free to swap whatever you want into your project. But don't assume that fewer cylinders or less displacement automatically means it's a smaller or lighter engine.

This isn't exactly what we're talking about, but it does a good job of illustrating the size differences of a DOHC v engine vs a pushrod engine.

Personally, if I were trying to get 300ish horsepower and lightweight combo, I'd be looking into turbo charging a 10-15 year old aluminum 4 cylinder. A turbo Duratec, Ecotec, SR20, etc will be way less weight than the big v6 or v8 options, and you don't have any of the complex electronics to battle.

In reply to yupididit:

Overseas still gets the Montero, with the 3.8 and a rwd transmission. The bellhousing from that doesn't have any options?

carguy123 wrote: Most of the V8 Locost people just stick it in a gear and "let the torque carry you through". You can do that, but it's not as fun or as fast as an engine and tranny that lets you use the engine to it's full potential. If I'm going to have to spend the amount of money it takes to keep a V8 monster in tiresome etc. then by golly I want to be one of the fastest guys out there. Look at the speeds of those little SAE race cars the universities make. They don't look like much but they let you take advantage of everything you've got. The weight of the V8s make cornering & braking slower than the lighter more nimble cars.

You can make full use of a V8 as well, it just means you're going faster when you do it. Same argument you can make with a V6 vs I4. Not everyone's ready for that sort of speed level so they don't drive them as hard. It's always easier to get maximum speed out of a slow car because the consequences are so much lower.

I have datalogs that would indicate that the mid-corner speed of a V8 Miata is no worse than that of a turbo I4 car. Same driver, same track, same day. Braking's harder to identify because the V8 car is starting from a faster speed and you do have a harder time keeping the brakes cool because of it. Generally speaking, you have to run a different brake setup. Remember, kinetic energy goes up with the square of velocity. Those datalogs also show a faster turn-in on the V8 car, which is contrary to legend.

Since this thread is very specifically about all-aluminum DOHC V6s with no turbos on them, I'll keep any further comments restricted to those lines.

At the end of the day we are all talking about 50-100 LB difference over the front end. The big difference in the weight of the swap is the transmission and rear end to support it. There is not a lot of difference in weight. Now if we are talking old school motors then it's a different story. My 340 engine is a lot heavier than the LS even if I were to put AL heads on it.

An LS is overall a pretty light package. I mean 2800 LBs for 400ish WHP in the heaviest factory miata ever made isn't bad at all. With the weight reduction from the coilovers, brakes, and wheels the impact over the front is not bad at all. The steering feel is pretty damn good. I have no issues with the overall feel.

At the end, It's about head room and growth. If you want 300 WHP then there are a ton of choices. I personally think an LFX miata would be a fun track toy. If you want more than 300 WHP, Then the options are more limited and regardless of engine choice you will have more expenses in consumables. It's great that we are able to have all of these choices available to have this conversation to be honest.

I was thinking while driving this morning, going back to this.

Nick (Bo) Comstock wrote: I'm wondering if you couldn't just fab an intake, stick some regular injectors in the runners, and add a normal throttle body in front of the plenum and then run it with Megasquirt.

It would be really interesting to see what the result was of a back-to-back test of a modern V6 with one that's been backdated to a simpler fuel/ECU setup. DI piston designs look radically different from port injection ones. How much of the power level is due to DI? Or would you mostly see the changes in economy, driveability and emissions? How much time would you have to spend on the dyno to figure out the best interaction between the two pairs of variable cams? I know that the Skyactiv four cylinder motors do all sorts of interesting things at different times.

yupididit wrote: I was looking at v6's that are NA to put in my Conquest. The LS plus t56 = lots of cutting. And I'm not interested in doing an LS at all. I want something that can be found easily but also different. The 3.7 ford looks like it would be a great engine it just hasn't been done much or popular. Other v6's I'm looking at 1gr/2gr, j35/37. If all else fails, I'll go back to a 1uz lol

That is another car I would go v8 or i4 turbo, lol. I always wanted a 4G63 Conquest.

A Conquest with a 360 in it would be all kinds of cool.

LS = more weight & more money.

IDK about that. You can get a 5.3 or a LS1 for almost nothing. Meanwhile these big power V6s how much are they going for? On top of that more money also includes supporting mods for the engine and research for it and mounts among other things. You can buy LS mounts for many cars. I think money is clearly on the side of the LS vs a V6 nobody uses.

A far as gas is concerned how is a V6 any better? I've had a 350Z in the past and it wasn't exactly fuel efficient. Like if you look up the fuel economy of a V6 camaro and a SS the city MPG is only 2 off. Also if you are putting the v8 engine into a light car like a miata instead of that camaro you probably are making much of that up.

I doubt the weight difference is much, in fact I would wager that a LS is lighter than a DOHC V6.

That would be really cool. Unfortunately, 6g7* engines don't have rwd options. Not any that make them worth trying. There's a conquest with a 6g72 swap with a th400 that was attached using a very custom setup made by bill hincher. It made about 800hp on megasquirt.

Ya that would be a waste of time. If I wanted a 6 cylinder engine to put into a Conquest that is turbo I would check to see if a straight 6 would fix. If so then JZ or RB. If a V6 is needed then I would look at the VG30DETT/ET/DET. I guess that Mitsubishi setup isn't a waste of time if you are using it in some racing series that requires the drivetrain make to match the car.

An aluminum V6 weighs more than an aluminum V8?

A modern DOHC V6 would possibly weigh more than a OHV V8 engine when made out of the same material, yes.

Overseas still gets the Montero, with the 3.8 and a rwd transmission. The bellhousing from that doesn't have any options?

If we're going to use a truck engine why not just properly build the 4G54 and use a properly sized turbo at that point.

Basically the only benefit here is "being different". You won't necessarily get a lighter engine. You will have less support. It will NOT be less expensive. Any MPG benefits are negligible.

Basically:

Starion - Built 4G63 for 300hp would be an ideal engine, could be done with a 16G or a more modern turbo (GTX2863) with great response. The 4G54 could support this. LS V8 is always an option. Why go for a Truck's v6? Their performance V6 engines are for FWD cars and so need significant work.

IDK what other cars we're talking but, Miata? You can literally buy mounts to bolt in a LS to a point where it's child's play. If "cost" is the reason for a V6 that is no reason here. As someone has shown DOHC V6s are not saving on side and also likely weight. If you want less weight get a SR20DET.

In reply to kanaric:

No I'm saying use the truck bellhousing on the mivec v6 from the eclipse, not use the truck v6. Adapter plate to a w58 or r154 if you can.

I'm still hoping there's a rwd option for the 6A12 because I want a really old Colt with this sound in it.

https://www.youtube.com/watch?v=QeMWTxeTBVI

"If you can leave two black stripes from the exit of one corner to the braking zone of the next, you have enough horsepower." Mark Donohue.

"No, it will never have enough power until I can spin the wheels at the end of the straightaway in high gear. Too much power is never enough...." Mark Donohue

"We're far from having too much horsepower...my definition of too much horsepower is when all four wheels are spinning in every gear." Mark Donohue