transwiz

iTrader: (26)

I would like to install a bigger cam in my t/a. I am currently running a Lunati 221/221 558/558 @114 cam. I have 317 heads that are ported with 2.02 intake and 1.57 exhaust valves. The heads are milled .036 .
I talked to a mechanic that i have some experience with about this. He said that I have to be careful how much lift and duration I have in a new cam because of the milled 317
heads. I am using gm head gaskets .052 if I remember correctly.I was thinking of a custom spec cam around 224/230 581/588 @ 113. What do you guys think?
How much duration and lift can I get away with? I also forgot to mention that I live in southern California.

A.R. Shale Targa

iTrader: (2)

Duration is what puts the valve and piston in the same vicinity
Max lift occurs when the pistons are nowhere near TDC
Valve drop is what’s needed for Steve from Cam Motion to get you a custom
Valve tickler that fits. Your duration numbers are “ballpark”

transwiz

iTrader: (26)

. I don't want to take any chances with this stuff.This mechanic said that I have to be careful with the duration come to think of it.I did some searches and came up with
228 max would be safe. Don't remember where I found this number exactly.

transwiz

iTrader: (26)

Someone on here must have some experience with milled 317 heads and what cam is safe.

sillysspeed

iTrader: (21)

I don’t have a scientific answer for you but 317’s milled .036 with a .052 gasket is not much at all. Around a stock 243 as far as clearance? You’d have to check cc’s on both heads. I’d talk with whoever is making the Cam but you should have plenty of room

transwiz

iTrader: (26)

From what I remember I was told by west coast cylinder head that they were 65 or 66 cc.They were the ones that did the valve install with the 2.02" 1.57" and the milling.

ArcticZ28

iTrader: (14)

I've got ported 317's that have been decked (an amount I can't quite recall), am running only .040 cometic gaskets, and I run a much larger cam without issue - 244/248 .635/.627 112 cam.

Of course, no promises, but that's where I'm at.