Aftermarket Cams in the 3.1L

[IDCavalier]

Hi gang,

Any thoughts on the options available regarding aftermarket cams for the 3.1L?

[IDCavalier]

This is my first forum.

I wish I would have known these existed before I started to work on my 1993 J-Body.

There's a lot of knowledge here and I am appreciative for the chance to talk with some people with experience.

[robertisaar]

there are a LOT of options for the LH0 when it comes to cams.... WOT-Tech has a lot of grinds listed.

[Superdave]

are you a member on V6Z24.com?

Cam choice is really going to depend on what you want to do with the car. Drag race, road race, circle track, looking to have some street fun or just want it to idle like a beast?


You can get pretty much anything you want these days, don't expect massive power gains with just a cam though. The gen 2's top end is it's major restriction.

[IDCavalier]

I am in the process of joining V6Z24. I heard that a lot of guys are swapping 3x00 heads out on the 3.x blocks.

[IDCavalier]

I think I might have made a mistake. I installed a comp cams rv cam when I rebuilt the 3.1. This was before I knew anything about this stuff. Ha ha.

[IDCavalier]

I am just not getting any power out of the new engine. I have been working on it - figuring out the problem. Compression is good : 180 across all six. Put in a flash ecm and I'm running Tunerpro. Got a wb to trim fuel and been playing around with SA. But I think I might need to open up the top end, huh?

[IDCavalier]

Oh! This one is great. I didn't know that the base circle of the new cam was different, so I bent a few pushrods before I figured that out! Runs better now that the valves close! Ha ha.

[Superdave]

The 3x00 head swap is not as popular as it used to be, most people just swap in the whole 3x00 engine. It's still a good option if your 3.1 bottom end is in good shape though.

Did you use the same username for V6Z24? I know the admin gets a little backed up on new accounts some times.



the base circle should have been the same or smaller on that aftermarket cam. which one did you use?

[SappySE107]

Usually pushrods are bent by mixing up intake and exhaust. Base lobe can't possibly be big enough to case the pushrods to be long enough to bend. After spending thousands on a 3.1 in the past, I can say that I won't do that ever again. I have a stock 3.1 in my cavalier and its going to stay that way minus some headers before I swap in another motor.

[IDCavalier]

I used idcavy93 in v6z24.
The cam I used is a comp pn 16-115-4. It has 260/260 lift which is actually less than stock, if my chilton manual is accurate. But Bob over at dynamic efi was helping me with it and that's when I discovered the bent pushrods.

[IDCavalier]

I used the comp cam p/n 16-115-4. It has .260"/.260" lift, which is less than stock, I believe.
I'm waiting for approval at v6z24 as idcavy93. I hope it comes through soon.
I think the bent pushrods might have been because I used stock pushrods with the aftermarket Comp lifters.

When I tore the intake off to see what was up, my intake valves were coated in some kind of greasy soot-like substance.
Some of my lifters were as high as .300" pre-load: according to Comp, they should be around .100"

[IDCavalier]

Thanks!
Is LHO the designation for these engines (Gen II?)

[IDCavalier]

Right? I bought this car from my neighbor's Ex gf for $400 and it ran well. Then when the blow-by was more than I could stand, I thought I would rebuild it. Then I thought that I would just put in a salvage 3.1 (first mistake?) THEN I thought I needed to rebuild the salvage one. And, while the engine is out, why not rebuild the THM 125C, right? Point being, I have put like $2000 into a $400 car. The Trans runs GREAT! but the engine has not ever been as powerful as the old, worn out one it came with!

Usually pushrods are bent by mixing up intake and exhaust. Base lobe can't possibly be big enough to case the pushrods to be long enough to bend. After spending thousands on a 3.1 in the past, I can say that I won't do that ever again. I have a stock 3.1 in my cavalier and its going to stay that way minus some headers before I swap in another motor.

[Superdave]

That cam is pretty much the same as the stock LHO (yes, LHO is the 3.1) cam, this is the one that most people use in the gen 2 engines: http://www.compcams.com/Company/CC/c...x?csid=57&sb=2

you'd need upgraded valve springs, stock will bind and break pretty easy.

Also, upgrading to some 1.6 rockers from a 94/95 Gen 3 3100 will gain even more lift.


Like Ben said, the pushrods won't bend on a cam swap like this unless you mixed up the intake and exhaust. It's a common mistake with the way the heads are set up. IIRC the exhaust ones are about .3 longer than the intake


Comp's lifers are the same specs as stock and meant to be used with the stock pushrods,