One more 2.7i thread

[e30trooper]

So I need some ideas. Ill be doing the e to I head swap in the next few weeks. Just got the head,intake (fuel rail w/ stock injectors) and late model auto Tb.
Besides the genral parts needed, what else can be done for added power.


Parts I have.
325e block , head/intake from a late model auto. I also have the miller maf kit w/19# tune from my last car but might sell it. All this with all new gaskets. Head will be hot tanked / decked. Im willing to try my own luck this doing a small pnp. Im in the looks for a reground cam.
My biggest downer will be the loss of compression due to swapping the head. What I want to know is how far can I deck that head and stil be in a safezone.
Im not looking for crazy power, just more than a fresh b25. So if anyone has done this same build id like to hear some thoughts.

[devon.818]

So I need some ideas. Ill be doing the e to I head swap in the next few weeks. Just got the head,intake (fuel rail w/ stock injectors) and late model auto Tb.
Besides the genral parts needed, what else can be done for added power.


Parts I have.
325e block , head/intake from a late model auto. I also have the miller maf kit w/19# tune from my last car but might sell it. All this with all new gaskets. Head will be hot tanked / decked. Im willing to try my own luck this doing a small pnp. Im in the looks for a reground cam.
My biggest downer will be the loss of compression due to swapping the head. What I want to know is how far can I deck that head and stil be in a safezone.
Im not looking for crazy power, just more than a fresh b25. So if anyone has done this same build id like to hear some thoughts.

it is evident someone has not tried searching.
FIRST read my 2.7i thread, next read what i type after.


no need to deck the head, you wont notice it.
a cam is your best bet, the maf will help, a lightweight fly wheel will make it more enjoyable. some IE HD rocker arms and a 7400rpm revlimit would be a great idea. free flow intake and exhaust a must. a 4.10lsd is a good idea.
honestly id get a new chip, one tuned for the 2.7i and whatever mods you throw at it from miller, yes they can do it, been talking to one of their vendors for mine.

the 2.7i excels on boost, so do a very mild turbo set up, spend under 800 and run 7-9psi of boost, obviously wait till a turbo set up pops up for sale and snatch it.


and you will NOT have more power on a rebuilt head 2.7i than a fresh resurfaced 0mi b25, think about it, a new motor vs a sort of touched up motor.

[e30trooper]

Yea ive read yours. Its a little hard to use search on my phone. You and I both know I allready have a turbo kit for an m20 (pretty sure you sent me a pm about it). However im not looking for boost. Im looking for na power. How is decking a head to rase comp. Not going to effect power?

[devon.818]

Yea ive read yours. Its a little hard to use search on my phone. You and I both know I allready have a turbo kit for an m20 (pretty sure you sent me a pm about it). However im not looking for boost. Im looking for na power. How is decking a head to rase comp. Not going to effect power?

I'm saying the amount of compression lost is not noticeable, now if you want a high comp screamer, get high comp pistons and do what ski free did, side drafts weber conversion

[e30trooper]

I'm saying the amount of compression lost is not noticeable, now if you want a high comp screamer, get high comp pistons and do what ski free did, side drafts weber conversion

Yea im not tring todo that. Theres a euro eta at a local yard but I drive my car to work everyday so downtime is only oneday. I was just wondering what kind of gains with a cam maf kit, small port and polish, head decked as much as I can safely do.

[Stephen]

you wont notice the compression difference, its really not a big deal. Decking doesnt get you too much

[shaferbm]

Why no 731 head? I'm no expert but you won't lose compression with one.

[e30trooper]

you wont notice the compression difference, its really not a big deal. Decking doesnt get you too much

I hope not. Im just hoping it will pull harder than my vert I just sold

Why no 731 head? I'm no expert but you won't lose compression with one.

not that easy to find and they cost alot more than heads here state wise. I paid $99 for a good head with intake,injectors tb.

[acolella76]

no need to deck the head, you wont notice it.
a cam is your best bet, the maf will help, a lightweight fly wheel will make it more enjoyable. some IE HD rocker arms and a 7400rpm revlimit would be a great idea. free flow intake and exhaust a must. a 4.10lsd is a good idea.


and you will NOT have more power on a rebuilt head 2.7i than a fresh resurfaced 0mi b25, think about it, a new motor vs a sort of touched up motor.

1) Why would you want a rev limit that high? The 2.7i stops making power at 6k rpm. All you would be doing at 7400 is breaking rockers.

2) Yes he will. I promise you my 2.7 would have made more hp than a rebuilt B25 if I had taken the time to get it tuned.



Cam would be good, headers, MAF or MAP sensor, etc. Just get the head to flow as much as possible! If you want to try your hand at gasket matching go for it, but I would advise against porting. It is easy to make it flow worse than before if you don't know what you're doing. Believe it or not, the engineers that designed the head knew what they were doing and got it to flow pretty well!

The compression difference is not a big deal at all, as others said. CR will be close to 8.5:1 vs stock 8.8:1. Not anything you will notice.

If you are going from M20B25 you may be a bit let down. My UNTUNED 2.7i felt just like a stock B25, with a bit more torque... I wish I would have taken the time to actually tune it.

[e30trooper]

I plan on just smoothing down the oem casting marks. I was thinking aboyt the port gasket matching and matching the intake also. Id be happy with the power I had in my vert (stock overbore, chipped 153,19#ers and a adjusted afm.) Very stout engine, a vert that could cherp 3rd gear lol.
Not sure if im going to run the maf kit, on the vert it felt like it had more power with the set I stated b4 but I could be wrong with eta. I was looking at a 288 cam here on tne local cl but that might be a lil steep for a dd,so I might just go with a 272. Ill be running the stock exhaust manifolds for now. My budget for this build is just under 800.

[BenMGP]

I just got my 2.7i completed not too long ago. I wanted to get a base tune just to see where i was at.

My current setup: Super ETA block, 885 head, stock manifold, headers, exhaust. Only mods were 19# injectors and cone filter.

170 hp
178 torque

Going back after I put on an exhaust and high flow cat.

I am also going to swap my 4.10 lsd out for a 3.73 or 3.46

With the 4.10 i find the gearing way too short for my tastes, and if i decide to boost... i bet it gets worse

[e30trooper]

I just got my 2.7i completed not too long ago. I wanted to get a base tune just to see where i was at.

My current setup: Super ETA block, 885 head, stock manifold, headers, exhaust. Only mods were 19# injectors and cone filter.

170 hp
178 torque

Going back after I put on an exhaust and high flow cat.

I am also going to swap my 4.10 lsd out for a 3.73 or 3.46

With the 4.10 i find the gearing way too short for my tastes, and if i decide to boost... i bet it gets worse

Im guessing 170hp at the crank. Yea ill be using a 86 eta block so with the head work planned should make more than 170 at the crank even with the comp loss

[BenMGP]

170 at the wheels.

[e30trooper]

170 at the wheels.

no shit! Thats very good numbers then!

[Stephen]

Why no 731 head? I'm no expert but you won't lose compression with one.

You wont, but its an inferior head. The compression is vastly outweighed by the better flow of the 885 head. Not to mention availability. I actually had a 731 head, but ended up selling it and getting an 885.

I hope not. Im just hoping it will pull harder than my vert I just sold

not that easy to find and they cost alot more than heads here state wise. I paid $99 for a good head with intake,injectors tb.

I have a 2.7i thats setup similar to the guy above (#19, tune, no cat 2.5" exhaust) and it pulls harder than any stck m20b25 i have driven to date. Perhaps there are b25s out there that would, but i havent driven one.