few questions

[95cobra]

i am starting on my procharger upgraded monday. doing head, cam, intake, injector,etc swap also. do i need to put cam on 0, advance, or retard it. i have a msd btm im installing also.what would be a good starting point on the base timing. next is fuel pressure what would be a good starting point on that also. injectors are 42#.

[SkurdalenFox]

What cam?

[95cobra]

its a E cam. i am building a stroker short block which i will use a different cam, but thats in the future. so for now jus E303

[QWKSNKE]

install the cam straight up. no advance or retard.
On the MSD BTM. I can't remember how the knobs are setup but you only want about 18 degrees timing max on an intercooled setup at WOT.

If a sn95 EEC is like a fox EEC, I would have the btm setup where it is pulling 11 degrees total timing at full boost. (This is based off 'base timing being' set at 10 degrees)

Fuel press should be set at stock (40psi VAC off) to start with

[LeeH]

its a E cam. i am building a stroker short block which i will use a different cam, but thats in the future. so for now jus E303

I would run the stock cam with 1.7s over an E303 when boost is involved, You're going to be blowing alot of the intake charge out through the exhaust.

[95cobra]

it has a 12# pulley on it so u think 11 degrees will be enough?

[95cobra]

I would run the stock cam with 1.7s over an E303 when boost is involved, You're going to be blowing alot of the intake charge out through the exhaust.

can you explain, because im new to boost.

[LeeH]

can you explain, because im new to boost.

Valve overlap, It's when the exhaust and intake valves are open at the same time(exhaust valve is closing and the intake valve is opening at the end of the exhaust stroke and the beginning of the intake stroke). This is done to help scavenge a cleaner intake charge into the cylinder, This is done for naturally aspirated applications which have to rely on atmospheric pressure to fill the cylinders. An application where boost is used doesn't need the increased amount of overlap because your intake tract is under a positive pressure, All overlap will do is allow fresh air to be blown out of the exhaust thus wasting potential power. The stock cam works good with boost and the savings can be applied to your stroker build, The stock cam with 1.7 rockers will give you .474 valve lift and a very tame idle. It makes for a real fun daily driver and has the stealth advantage, If you do go with an aftermarket cam find one with a minimal amount of valve overlap.

[95cobra]

gotcha thanks for the valuable info.

[coupe]

The E303 is on a 110º LSA. The stocker is on a 115 or 116º LSA. Same cam with smaller LSA has more overlap. The overlap issue is particularly important on a turbocharged setup.

[LeeH]

The E303 is on a 110º LSA. The stocker is on a 115 or 116º LSA. Same cam with smaller LSA has more overlap. The overlap issue is particularly important on a turbocharged setup.

LOL, Yeah I didn't think about telling him to look at the lobe seperation angle to gage overlap. The stock cam can range from 115 to 117 depending upon year, application and the accuracy of the grind.