Boosted m20 2.5 to 2.7 stroker question!?!

[GUERONASTY]

So started my budget build building my first engine build/rebuild to drop in my boosted M20. I have an '86 2.7 M20 block and a '89 2.5 M20 head. Just got everything back from the machine shop and all new maintenance parts arrived. I'm stuck at the moment and need some help. Been reading that I have to either A) Run '88 SETA pistons B) Run "i" pistons shaved 2-3mm C) Custom pistons. My question is is that only for N/A or boost aswell or can I run it like that (or is compression to low)? If it were not to be possible just gonna run my existing M20 "i" block that's in car already with the fresh "i" head nnd use my money to go Megasquirt instead!

[TheTacoMan]

You can use the stock e pistons with the "i" not the most ideal but it works fin IMO

[GUERONASTY]

You can use the stock e pistons with the "i" not the most ideal but it works fin IMO

Not to convincing lol think I stick to 2.5 bottom end and "i" head

[Ceeker]

I got the same set up and running 10lbs boost. e 2.7 block with I head. everything is stock motor wise.

[GUERONASTY]

I got the same set up and running 10lbs boost. e 2.7 block with I head. everything is stock motor wise.

How's that running? What compression does that make? Power?

[TheTacoMan]

How's that running? What compression does that make? Power?

Look up the two kamotors built recently, they are both 85e s and they made good power. Both are very fast.

[GUERONASTY]

Look up the two kamotors built recently, they are both 85e s and they made good power. Both are very fast.

Could not find it. Link to share?

[AbsorbantNut]

http://lmgtfy.com/?q=kamotors+turbo+r3v

The top result & the two bullets below it. I believe those are the ones he's talking about

[GUERONASTY]

Still can't figure out weather to run...
1) "e" 2.7 block with "i" 2.5 head
or
2)"i" 2.5 block with "i" 2.5 head
...on boost. What will be ideal for it?

[andrewm]

Still can't figure out weather to run...
1) "e" 2.7 block with "i" 2.5 head
or
2)"i" 2.5 block with "i" 2.5 head
...on boost. What will be ideal for it?

that depends on your goals.

The E bottom will have lower compression, but more displacement.

The I will have higher compression, and be trickier tuning because of that.

I'm building an E motor with and I head for boost currently because I'm only an OK tuner. Last time I got really into a car was an MR2 and I BUILT the motor. With forged internals I opted for the stroker motor with higher compression ratio because...torque But with the e30 I'd rather have the displacement and margin for error.

[TheTacoMan]

Still can't figure out weather to run...
1) "e" 2.7 block with "i" 2.5 head
or
2)"i" 2.5 block with "i" 2.5 head
...on boost. What will be ideal for it?

Research. Google. Search.

[GUERONASTY]

Research. Google. Search.

That's all the same thing.

[einstein57]

Several people have said its fine. Need a letter from BMW NA too? lol