b20b rebuild...milling head

[Charlie Moua15]

This if for my kid brothers build...

after the rebuild we are hoping to make about 145whp and 140tq on e85
Keep in mind I will be boosting it next year with garrett T3 super 60 & make 250whp @ 7-8psi


So far this is in the rebuild :

- jdm b16 s1 tranny (4.4 Final Drive FTW !!!)
- exedy 9lbs flywheel
- exedy clutch
- arp rod bolts
- arp head bolts
- oem head gasket
- npr rings on stock pistons
- fresh hone
- stock cams (might go with 62403 later on)
- tri-y replica header (2.5" collector)
- 2.5 exhaust
- chipped po6 crome
- CAI
- walbro 255lph fuel pump
-e85 with pte 780cc injectors




Looking to get compression to about 10.1 but no higer than 10.5

Q:

1) can I shave the stock head down to 0.075?
http://www.zealautowerks.com/bseries.html
says that if I milled head by 0.075 it would bring my cr to 10.45cr.

2) is 0.075 enough to affect timing issue where I would not be able to correct it by adjusting the distributor?

3) when you shave the head, do you have to take off the valve springs too or just the cams & rockers?



LMK - charlie Moua

 

[SexySSBP]

1. I seriously doubt you could mill .075 and be ok. At that point, you would be cutting into the valves, lol...

2. Yes, I believe the rule of thumb is half a degree for every .040. You will be a full degree off. It might even be a degree for every .040...just search and you'll find it...

3. Like I said, at .075, you'd be cutting into your valves, but even less and i think the valves are normally removed. I could be wrong. Ask your machine shop. You should get an inspection and valve job done when the head's at the shop anyway.