Gen 3 2.8L or not...

[IsaacHayes]

carbon, yes you'd need custom pistons since nothing in the 3.4l bore had a 2.8 crank in it.

[sanjay]

I'd use 3500 exhaust manifolds like we did on Redbird's 3500. they're badass.

2.25 would be plenty for this setup.



Abob is driving his 3400 '89Z on a stock clutch. It will slip under load but for daily driving i'm sure it's fine.

As much as I'd love the 3500 ex manis it's just an extra expense that's not needed.

As for Abob's car with a stock clutch well you're making me want to just go with the extra displacement of a stock 3100....But a 2800 would be so much more interesting...

[ghrarhg]

I'd be interested to see how a high compression 2800 turned out. My 2.8 hybrid really lacks on the low end. Stock 2.8 bottom end with 3400 heads actually dropped my compression ratio down to 8.5 according to the CR calculator. The turbo + cam really wake it up over 3k though

[sanjay]

I'm having trouble sourcing the 2.8 Crank and pistons. Can I use a 2.8 RWD Crank?? I may just buy a complete 2.8 RWD motor to get the parts I need.

[IsaacHayes]

More info on your setup ghrarhg ? I never knew you had that setup...

[IsaacHayes]

2.8 RWD crank lacks crank trigger IIRC. And it's external balance I think.

[sanjay]

2.8 RWD crank lacks crank trigger IIRC. And it's external balance I think.

That answers that..FWD crank it is..

[ghrarhg]

I just finished it this May-ish. 88 2.8 block, crank, pistons. 3400 heads, LIM, UIM and TB. 26986 springs, engle 1605H cam, comp lifters, tgp manifolds hogged out to fit 3400 D shape, tgp crossover and turbo, diy full 3" exhaust from the turbo back.

I have a 3500 UIM, and 3.5 LX5 TB, but unfortunatley, it looks like the tgp crossover puts the throttle body into the turbo. It'll have to wait until I upgrade the turbo and build a new x-over/manifolds.

Idle vid from when I first got it running:

http://www.youtube.com/watch?v=WyJriS5r0RY

[WrathOfSocrus]

2.8 RWD crank lacks crank trigger IIRC. And it's external balance I think.

The newer blocks such as most of the TBI 2.8's found in the S10's were internal balance and from what I understand they used the reluctor wheel cranks in some of the RWD blocks.

BTW this is a very interesting build trying to get good fuel economy and some performance!

[sanjay]

BTW this is a very interesting build trying to get good fuel economy and some performance!

It seems to be gathering quite some interest..More info on the condition of the 3100 tomorrow..

[SofaKingWeToddDid]

I don't think you could short stroke the 3400 with the 2.8 crank... the pistons have a different pin height besides the longer stroke. I don't think the 3.4/3400 pistons would come far enough up the bore to make compression...

Turbo that shit then. and supercharge it.

[carbon]

Well no... its to low to even start...

[1QUICKHATCH]

I'm having trouble sourcing the 2.8 Crank and pistons. Can I use a 2.8 RWD Crank?? I may just buy a complete 2.8 RWD motor to get the parts I need.

what is the casting # on the 2.8 fwd crank? I may have an extra one kicking around.

[sanjay]

what is the casting # on the 2.8 fwd crank? I may have an extra one kicking around.

No idea..Can anyone help with the casting number here?? The crank I was supposed to get is apparently a 3.1 crank.

[1QUICKHATCH]

I looked at my 3.1 crank today and it said 981, I will check my other cranks on saturday.