Compression ratios

[MMarauder03]

So I'm doing a bunch of maintenance work getting ready to supercharge my MM. I'm going to be replacing timing chain and tensioner because it's about that time and was thinking 10.1:1 compression ratio seems wayyy too high to just throw a supercharger on it. Most supercharged applications are 8.5:1 if not lower. Now somebody correct me if I'm wrong, and I seem to be since a good portion of marauders are supercharged now doesn't that seem like a ticking time bomb?

[ImpalaSlayer]

So I'm doing a bunch of maintenance work getting ready to supercharge my MM. I'm going to be replacing timing chain and tensioner because it's about that time and was thinking 10.1:1 compression ratio seems wayyy too high to just throw a supercharger on it. Most supercharged applications are 8.5:1 if not lower. Now somebody correct me if I'm wrong, and I seem to be since a good portion of marauders are supercharged now doesn't that seem like a ticking time bomb?

you can run boost with 23:1 compression just like diesels. idealy yes you would want lower compression on a gasser but you dont HAVE to have it. you just compensate for it in the tune and amount of boost you run.

[MMarauder03]

you can run boost with 23:1 compression just like diesels. idealy yes you would want lower compression on a gasser but you dont HAVE to have it. you just compensate for it in the tune and amount of boost you run.

That's what I was thinking, well if I were to bore my stock block .020 over since it does have 115k, forged pistons and crank. Now there are manley pistons with a 23cc dish that would put a 4valve 4.6 at 8.06:1. Would there be any qualms about boosting the piss out of it? Obviously with supporting mods

[ImpalaSlayer]

That's what I was thinking, well if I were to bore my stock block .020 over since it does have 115k, forged pistons and crank. Now there are manley pistons with a 23cc dish that would put a 4valve 4.6 at 8.06:1. Would there be any qualms about boosting the piss out of it? Obviously with supporting mods

im no expert when it comes to this stuff but that seems low. i would bore it min amount possible if its needed at all. boring a motor to get more cubes on a street car is just stupid IMO. iirc stock cobras run about 8.5:1 CR. hell i pumped 14psi into my stock engine and fed it the full 14 every chance i got and so does the new owner.

if i were you and you are going into the engine regardless, id go 8.5ish with good forged rods and pistons and call it a day.

if it were me, id feed that ***** like it sits and buy stock in rubber, these motors are stronger then most give credit. they only fail when people do stupid things or push them beyond what is considered "safe"

[SpartaPerformance]

I'd stay at a 10:1 compression. Unless it's a track car and you're going to pack in 20+ psi no reason to lower it.

[MMarauder03]

I'd stay at a 10:1 compression. Unless it's a track car and you're going to pack in 20+ psi no reason to lower it.

Thanks sparta and dave. Looks like you guys saved me a ton of money! Now to throw 2,000 in my supercharger fund. I'm almost there

[ImpalaSlayer]

Thanks sparta and dave. Looks like you guys saved me a ton of money! Now to throw 2,000 in my supercharger fund. I'm almost there

np, i was a little nervous about putting boost to the stock motor but with a good tune you got nothing to worry about as long as you dont go attempting to make 500hp.

[MMarauder03]

np, i was a little nervous about putting boost to the stock motor but with a good tune you got nothing to worry about as long as you dont go attempting to make 500hp.

The plan is to tide me over until i get an aluminator or build my own. Just tired of being slow

[ImpalaSlayer]

The plan is to tide me over until i get an aluminator or build my own. Just tired of being slow

i bet you will have an aluminator and will be wondering why the hell the stock one wont blow up lol

[FordNut]

I went with 9.5:1 cr

[MMarauder03]

i bet you will have an aluminator and will be wondering why the hell the stock one wont blow up lol

LMAO, hopefully!

[LANDY]

Put the blower on it first, when the stock engine blows up build a motor around 9.5;1 CR.
Done deal

[slickster]

Would you need headers for this upgrade

[burt ragio]

Depending on type of headers they would give you another apx 50 hp.

[slickster]

Wow 50hp from headers after forced induction. In that case it's worth a grand for headers