My 3100 build :)

[bkaab]

When you ask about differences between pistons, are you asking for like compression ratio?

As far as the rockers go, all 3x00 engines have 1.6 ratio rockers stock.

I know the compression is lower but are they made of something different of coated so the take better to boost?

[TGP37]

Stock pistons for my L82 are hypereutectics. I think the TGP had the same, but I can not be 100% about that.

[bkaab]

Well I got my new cam. Its not very big(Intake 280, Exhaust 294. With the 1.6 rockets it 448 and 470. Intake duration 204, Exhaust 214) but its better then stock I guess plus for 75$ shipped it was a good deal. Only issue is I didn't realize that its a flat tappet cam and not a roller. I can just run the old style 3.1 lifter and have no issues correct?

[TGP37]

why would you want to? Roller lifters are superior in wear protection and have a greater ramp rate which impacts performance.

Replace lifters, new pushrods, etc, etc. Probably better off having Ben build you a roller cam that will fit your engine nicely.

[bkaab]

why would you want to? Roller lifters are superior in wear protection and have a greater ramp rate which impacts performance.

Replace lifters, new pushrods, etc, etc. Probably better off having Ben build you a roller cam that will fit your engine nicely.

I wouldn't have bought it if I knew it was a flat tappet. I guess I will just run it till I do my 5 speed swap.

[TGP37]

I wouldn't have bought it if I knew it was a flat tappet. I guess I will just run it till I do my 5 speed swap.

I know you didn't, I was just saying if it were me, after I got done kicking myself in the arse, I would get a roller cam.

Sorry if I came off like a jerk, not my intention.

[bkaab]

I know you didn't, I was just saying if it were me, after I got done kicking myself in the arse, I would get a roller cam.

Sorry if I came off like a jerk, not my intention.

Your good, you're giving you're being honest and I respect that. You're helping me learn more about the 60 degree v6. If I asked some of these questions on clubgp about a 3800 they would 1st call me an idiot and tell me to do some completely different then I asked after that someone would come in and change the topic all together. lol

I wish I did but I will just have to wait till a later time to do it. It still will be better then stock.

[bkaab]

How much boost will a stock bottom end of a 3100 hold and still be reliable? I'm looking at running 8-10 if that is possible on a stock bottom end without blowing it to pieces.

[SappySE107]

a stock roller cam is probably better for boost than that flat tappet cam.

[zinX11]

How much boost will a stock bottom end of a 3100 hold and still be reliable? I'm looking at running 8-10 if that is possible on a stock bottom end without blowing it to pieces.

Hard to say with any reliability, but one thing is for sure, if you run into detonation, the stock, cast/hypereutectic pistons will fracture. It would be a very good idea to be conservative on the ignition timing and possibly add water injection. While the water doesn't add power, if it stops detonation, it will allow higher boost levels, which will allow higher HP.

My eventual plans include a boosted 3.1, but I've pretty much always planned on going with custom pistons, both to lower the compression, as well as gain some strength... I am curious how far the stockers have been pushed though... Might get to boost a bit sooner if I don't have to pony up the $$ for the pistons!

Mike

[Superdave]

you'll also have to switch to a gen 2 timing set and get custom length pushrods to run that cam. That's another $200 or so right there... then the zinc additive in the oil, cam break in and all that fun stuff.


Ben's right, the stock 3100 cam would be better.

[bkaab]

Ya well I guess if I am going as far as getting all the machining done I might as well get a new roller cam made for boost. Just got to see if I can't return this one or sell it.

[Superdave]

you should be able to sell it, 1st or 2nd gen guys would like it.

[TGP37]

How much boost will a stock bottom end of a 3100 hold and still be reliable? I'm looking at running 8-10 if that is possible on a stock bottom end without blowing it to pieces.

I can say I ran 8psi extensively on a sort of stock bottom. I upgraded the bearings and uses ARP rod cap bolts.

The stock roller cam does work well with boost.

Do make sure your knock sensor is working. Also should run a tad bit richer in boost to keep detonation at bay. 11.8 AFR is a good target for 5-8 psig to start.

The T04E 50 Trim Turbo is a great match for these engines.

[bkaab]

Well I guess I'm going to go back to a high compression setup for now. I'm running into too many road blocks and going to be throwing a lot of money at a turbo setup. I can gather parts to go over to a turbo later.