DIV 1 rally/track 4AGE(objective +- 130 whp)

[oldeskewltoy]

Quote:@oldeskewltoy
I have read your topic and there is really alot of good info there(still not done)
some things:
pon cams graph is with 12.2 to 1 compression,quite an important detail is missed.
t3 camgears give trouble



@oldeskewltoy
two important notes i have found in your thread

1:its better to not use ARP head studs
2:I'm using the OEM gasket... because nothing else seals BETTER

can you give a bit more information on this?


Ok thats a big reason,no arp head studs then,oil supply passage is very important.

Concerning camshafts... do some research into dynamic compression ratio... in particular @ the intake closing event.

If our 92 is close to your 95... and you have 98 available too....


the temp differences (210, 180, 170) is coolant temp.

You can see that you can run significantly more dynamic compression ratio (DCR) with lower temps... AND/OR higher octane fuel


The T3 pulleys didn't fit my Web camshafts correctly. I had to enlarge the hole in the back of the pulley to accept the pin.


ARP is very good stuff, and there is nothing wrong with using ARP. The factory head bolt is a very good product too. My opinion of the need for ARP comes to me from Loynings. They only use the ARP stuff on Formula Atlantic engines... and NOT all of those! If the engine is used as a part of the chassis, as in the F/A cars, the heads would get ARP studs. But frequently, on installs or use not in an Atlantic car, the head would be installed with headbolts. There is one potential problem with using ARP (not an oiling issue), on SOME peoples 4AGE engines, the head stud under the distributor is too tall, and the distributor gear hits the stud.

Quote:Im not 100% sure if i am correct herebut if i have 40/18 can i use +EM 40/20 connecting rod set then to be able to install the ae92 mm pistons?
The pistons from em on the website are 82.5 mm,isnt that a borderline overbore?

yes using +EM rods allows you to use OEM cast high comp (10.3 to 1) pistons.

Reason I recommend the +EM piston: 1) is they have some room for machining to "adjust" them to exctly what you, or your machinist wants, 2) the oiling from the rings to the piston internal structure are superior in design, and material - so far less chance of ring land failure. I believe the +EM pistons are also lighter... lighter means safer because the pistons mass @ 7500 rpm, is what can tear the crank and rods to shreds, lighter pistons means MUCH easier for crank and rods to survive

yes - stock bore is 81mm, so 82.5 is SUBSTANTIAL overbore. Send Jeff an email, ask him if the piston is available in standard bore, and 1/2mm overbore