Stock 302 Turbo

[Pitbull1052]

o.k. so my cousin and I are going back and forth about compression ratio's and how long a stock 5.0 motor will last. So he's building a turbo 1994 turbo 5.0. The only thing he's upgrading is the MAF, injectors, and fuel pump. So a stock 5.0 motor is at what about 9:1 compression? if he plans to throw 10 + lbs of boost at it he's going to be in the what 500 + hp range? my question is approx what compression ratio does that put it at at full boost? 13:1 + and I wouldnt think a stock block motor could live that long under those conditions.

[SN95N/A]

Over 500hp it will deffinately get iffy.

[Pitbull1052]

That's what I thought too but i'm not a turbo guy....... any idea what 10lbs of boost is going to do to the compression ratio? he will at least need to do head gaskets or something wont he?

[Gearhead]

That's what I thought too but i'm not a turbo guy....... any idea what 10lbs of boost is going to do to the compression ratio? he will at least need to do head gaskets or something wont he?

FelPro 8548pt-2 or FelPro 9333pt-1 for head gaskets and be done with it. No need for the high dollar ones at 8-10 lbs boost.

[Pitbull1052]

FelPro 8548pt-2 or FelPro 9333pt-1 for head gaskets and be done with it. No need for the high dollar ones at 8-10 lbs boost.




Thank you sir!

[slow86fiveoh]

My buddy runs a stock shortblock 89 with home ported heads, e cam, trick flow upper and lower and he is on 13psi and over 500 to the wheels for about 3 years now on a good tune but it recently started loosing oil pressure

[5.0calypso93lx]

o.k. so my cousin and I are going back and forth about compression ratio's and how long a stock 5.0 motor will last. So he's building a turbo 1994 turbo 5.0. The only thing he's upgrading is the MAF, injectors, and fuel pump. So a stock 5.0 motor is at what about 9:1 compression? if he plans to throw 10 + lbs of boost at it he's going to be in the what 500 + hp range? my question is approx what compression ratio does that put it at at full boost? 13:1 + and I wouldnt think a stock block motor could live that long under those conditions.

Boost doesn't change the compression ratio at all. Make sure everything is mechanically well, have a good tuner tune the car and keep it under 5,500rpm. Go beat the balls off of it.

[Pitbull1052]

Boost doesn't change the compression ratio at all. Make sure everything is mechanically well, have a good tuner tune the car and keep it under 5,500rpm. Go beat the balls off of it.



yea I'm sure he's not going to do any of that lol

[2Kblacksleeper]

Thanks brad this info helps me too. Ive already got a turbo kit lined up for the copper car.

[Pitbull1052]

eh no problem John i really am asking for my cousin though he's one of those types that asks you a ton of questions then questions your answers when you give them. lol I'm pretty sure the copper car already has head gaskets for boost but i dunno couldnt hurt to make sure...........

[Bman]

FelPro 8548pt-2 or FelPro 9333pt-1 for head gaskets and be done with it. No need for the high dollar ones at 8-10 lbs boost.9333 Is what i just put on mine.

[2Kblacksleeper]

I know you were. Just thought I'd say thanks anyway. Lol

[mustangboy]

Its all about keeping the rpms down and controlling detonation

[Walter]

Boost doesn't change the compression ratio at all. Make sure everything is mechanically well, have a good tuner tune the car and keep it under 5,500rpm. Go beat the balls off of it.

Boost wont change static compression ratio but does effect dynamic compression ratio.

[9cobra4]

Its all about keeping the rpms down and controlling detonation

Yep, if you rev the crap out of it, it will NOT last long at all. Like James said, keep the RPMs down in the 5,500 area and you won't crack the block in the thin areas like the cylinder walls to the edge of the block.

[Pitbull1052]

Boost wont change static compression ratio but does effect dynamic compression ratio.




Walter please explain further please

[Walter]

Walter please explain further please

http://www.hemrickperformance.com/Pages/dynamiccompression.aspx

Add boost pressure to the equasion under dynamic compression.

[Pitbull1052]

So Walter when we're talking the "standard" compression ration of a factory 302 being lets say 9:1 that's static or dynamic compression?

[Walter]

Static is a calculated compression ratio. Dynamic can be different from static due to ignition timing, camshaft specs, boost, altitude..... Dont worry about the cr on that motor, boost it up and keep the revs low.

[Pitbull1052]

thanks walter!!!!!!