V6 curiosity...

[jwevans1024]

Okay, so my Cobalt thread was odd but this one may be even more so. It's gonna sound very far fetched and probably wouldn't be worth the effort but I was wondering if anyone has ever tried (for a Z24 Cavalier) building a 3.1 V6 with the iron heads, a distributor, the Edelbrock performance 4bbl. intake manifold and a 4bbl. carb.? I always liked the idea of old school muscle meeting sport compact. I thought with a nice cam and some high compression pistons this might be an interesting combo? I dunno, probably just better off building the stock 3.1... Let me know!

[trotterlg]

I have sort of what you are talking about but with aluminum heads. Put iron head pistons in it for about 12 to one and a really big cam. Don't know how it runs yet but it will probably be fun. Larry

[jwevans1024]

Oh man, that's pretty damn cool! Judging by the layout I'm going to say that's going in to a Fiero? Is that top end a 3500 or a 3400? I like the idea of the 3500 manifolds too. My original idea was to use the stock LH0 3.1 block fuel injected, using the 3400 heads and intake, the iron head 2.8/3.1 flat top sealed power pistons, and maybe a crane 260 cam. I also considered using a 2.8 crank to reduce rotational mass, but I think it would sacrifice low end torque too much and throw the power band way too high. I like this setup you have though, very nice!

[ericjon262]

the iron heads just don't flow, I'd skip them, but that's just me. Also, the later blocks offer a factory roller cam

[jwevans1024]

Very true. The iron heads are unfortunately the easiest way to go for a carb. I'm probably just going to go with the 3.1 hybrid. I haven't seen significant enough gains with roller lifters to warrant a swap from a 3.1 to a 3X00 block. At least with the 3400 top end I get the roller fulcrum rockers, a 1.6:1 rocker ratio, and WAY better flow all the way around. That and there are way more cam options for the Gen1/2 flat tappet block and they seem to cost a lot less. A full Comp cams 60° V6 cam kit (includes 260 cam, all 12 lifters, valve springs, guide seals, caps, keepers, timing chain and gear set) is $319.95 from Summit racing. The cam alone is only $144.

[ericjon262]

yeah, but you can buy the whole engine for less than a set of heads, and then you don't have to tear it apart...

[trotterlg]

Yes, it is a Fiero engine. The flat tappet cams have some advantages, the lifters are a lot lighter than the roller lifters are and cams are a lot easier to find, also, the stock roller lifter cams are hollow with pressed on lobes, seems they have a bad habit of breaking, I bought a fairly hot cam and then took it to a cam grinder and had it bumped up from there, if you do that you can get exactly what you want. I think most of the after market cams have too much lobe seperation angle to turn out any power up high, guess we will see. If you run a cam with a lot of overlap you will need to bump the compression ratio up a lot because of the loss of compression caused by overlap, static compression calculations are only one part of the whole thing. Larry

[jwevans1024]

Yeah, the lack of a teardown is nice, but I plan on doing a full bottom end rebuild anyhow, so that bridge is burned. I agree with you Larry, I knew there was one other thing I didn't like about those Gen III engines, that damn hollow cam. I remember the initial 3100's and the big bulletin about the lobes spinning on the shaft, causing some interesting problems. We'll see, I have a nasty habit of changing my mind last minute! I have seen downfalls to extremely aggressive setups. I over ported a head once on a 16 valve Saturn and lost a TON of power. Funny, everyone says more flow= better, that's not always the case.

[ericjon262]

Yeah, the lack of a teardown is nice, but I plan on doing a full bottom end rebuild anyhow, so that bridge is burned. I agree with you Larry, I knew there was one other thing I didn't like about those Gen III engines, that damn hollow cam. I remember the initial 3100's and the big bulletin about the lobes spinning on the shaft, causing some interesting problems. We'll see, I have a nasty habit of changing my mind last minute! I have seen downfalls to extremely aggressive setups. I over ported a head once on a 16 valve Saturn and lost a TON of power. Funny, everyone says more flow= better, that's not always the case.

well, the Gen3 motors also offer a stronger bottom end too. flow+velocity= power. it really all depends on where you want the power, you really want the most flow, with the least port volume.

[Superdave]

the aftermarket cams for the gen 3 are all solid core, no need to worry about spinning lobes there. They're quite easy to find, the link is right at the top of the page.. lol



jwevans1024, i know a thing or 2 about making Z24 cavaliers fast... Stay far away from the iron heads and carbs. If you want something that's just stupid fun drop in a whole gen 3 engine.

grab a low miles 3500, toss in a street/strip cam, use the 3500 "header" manifolds and you'll have far more power than you'll get out of any hybrid.

[jwevans1024]

Yeah, that was the issue with the Saturn head, I greatly increased flow, but greatly lost velocity. I had just started modding cars then and I was experimenting all over the place. It ended up paying off, I built an engine for a 1996 Saturn SC2 that was normally aspirated. I managed to pull a 15.1 second quarter mile in it, fairly inexpensive build also. I took a stock 2000 Saturn 1.9 liter DOHC (roller followers instead of bucket lifters, factory coated skirt pistons, powder forged rods (I think that's what they're called) with the cracked caps), put in the crank shaft for a 1994 (14 lbs. lighter than the 99-02), ported the cylinder head and intake manifold, slightly larger throttle body, iceman short ram intake and full 2" exhaust system with 4-2-1 header.

Superdave, thanks for the info! I didn't even know the new cams were solid. I thought they looked different from the factory ones online but I figured that was because it wasn't a photo of the actual product! I'll have to read up on the 3500 swap. I just liked the LH0 idea because I didn't have to tinker with the engine mounts or the A/C. I also like the thought of bumping up the compression ratio however if using the Gen III engine will yield almost as much power without doing that, I may have to rethink the whole thing! I knew the gen III's had the stronger bottom end with that structural oil pan and the cylinder walls are thicker. As for the carb. thought, I just thought it would be fun. I looked more at the old cylinder heads and they are quite restrictive. Although vs. an old 2.8 MFI or a 3.1 they seem to do okay. Some of those old 2bbl. 2.8's had almost as much power as a 91-94 3.1! The other thing I wasn't fond of with the 4bbl. setup is only Holly makes a carb. small enough for a 2.8 V6. I don't like holly carbs, especially with GM vehicles. So yeah, I've pretty much set aside any carbureted ideas. I just like to be different!

Well you guys certainly have given me something new to think about! I'll explore more on here and see what others have done. Thanks for the info gents!

[jwevans1024]

Okay, one last question. I searched the v6z24 forum (I can't post because apparently it takes an act of God to get registration confirmation) to see if anyone has tried to rig up the Beretta torque axis mount setup on a Cavalier. I didn't find anything but I know J, L and N bodies are very closely related. I mean pre-1992 they all used the same mount setup as the J-bodies. I just think the TAM setup would solve a multitude of clearance issues and make certain swaps (e.g. 3500, possibly LZ4/LZ9) a whole lot easier. Just a thought, because after doing some research, it seems like a V6 swap would be easier in the gen III J body than the 2. I wouldn't do it because, in my opinion, the gen III is not only heavier, but doesn't ride or handle as well as the gen II. Oh well, it's a lot easier to make up your mind once the car is in front of your face!

[ericjon262]

Okay, one last question. I searched the v6z24 forum (I can't post because apparently it takes an act of God to get registration confirmation) to see if anyone has tried to rig up the Beretta torque axis mount setup on a Cavalier. I didn't find anything but I know J, L and N bodies are very closely related. I mean pre-1992 they all used the same mount setup as the J-bodies. I just think the TAM setup would solve a multitude of clearance issues and make certain swaps (e.g. 3500, possibly LZ4/LZ9) a whole lot easier. Just a thought, because after doing some research, it seems like a V6 swap would be easier in the gen III J body than the 2. I wouldn't do it because, in my opinion, the gen III is not only heavier, but doesn't ride or handle as well as the gen II. Oh well, it's a lot easier to make up your mind once the car is in front of your face!

I don't see how the Gen3 would be an easier swap in any way, esp considering the gen2 had a 60*V6 from the factory...

[jwevans1024]

Yeah, I meant because the gen III has the torque axis mount. It would be more of a pain in the a$$ in every other way! I get ideas and I tend to think out loud. I actually know very little about the gen III Cavalier, other than I don't like them! That and under the hood the gen III Cavalier is VERY similar to a '99-'05 Grand Am/Alero.

[Superdave]

swapping any V6 into a 3rd gen Jbody takes a ton of work, putting one in a 2nd gen takes a few hours. 3400 is pretty much a bolt in deal aside from the front mount, but you can build your own from plans that have been posted online. Or you can buy one pre-made. 3500 is a little harder but still can be done in a weekend.

http://www.v6z24.com/jbodyforum/3500-swap-details-t98567.html

I used the Beretta jackshaft, it's a good idea with the 3500 swap to keep the jackshaft alignment correct.


port flow between gen 1 heads and say 3500 heads is night and day. IIRC Gen 1's flow around 170 CFM @ .5 lift. stock 3500 heads flow around 225 CFM there, ported they can exceed 250 CFM. Lower lifts are also much better with the 3500 heads.


Same local dyno that I use for tuning, stock 3.1 5 speed put down about 110 WHP.. stock 3400 swapped 5 speed Z24's all put down between 190 and 200WHP with a good tune. We used to run quite a few cars at the V6 bashes through there in a few hours. Also the same dyno i put down 275 WHP with my old cavalier (P&P'd 3500, big cam & headers).


I'll bug Moonwell again about registration on V6, he's been extremely busy lately.