I just wondering if there is a company/shop that builds our 3.0 engines with forged internals to handle hi horsepower setups? If not, does anyone know where I can buy forged rods, pistons, crank, etc.? Also, what about aftermarket axles/CV joints? I don't want to worry about breaking those

 

I am almost sure that a 95 engine is a 4 bolt main so the bottom part of the motor should be able to handle high power.

This doesn't answer you question but may help you.

P

 

You will never need a forged crank. As far as rods and pistons go, any shop can build the motor for you, it doesn't have to be a nissan specialist. Just get the parts and they can do the work as long as they're competent.

 

The internals in a well-tuned VQ running sufficiently rich (12.5:1 at least) such be good for at least 450+ WHP. If you approach this mark, you should have already considered re-enforcing you tranny.

The pistons seem to be the main weak link in the VQ so you should go for those first to lower the compression if you do go custom...

 

I don't know too much about engines so this question may be kinda dumb but, how does lowering the compression help the engine? Performance wise? and does it effect the life of the engine?

 

over here in utah there is a place called RPM that does all that junk, they are like a machine shop, and i will let them do my motor, i heard alot of good thing about them.

 

No it's a valid question Lowering the compression actually takes away from engine performance for a given displacement, and thus is detrimental for any N/A applications. In a boosted application, it would make the engine more resistant to detonation when introduced with extreme cylinder pressures that could cause the air/fuel mixture to ignite before the spark is applied. So in doing this, it could allow for higher boost pressure, given the rest of the engine is up to the task...

 

I saw a web page of a company (forgot the name/adress of it) but they build complete racing engines for a tad over 3k.

 

So this is only something you do if your going to "boost" your car? And without forced induction it's a loss of power? I heard from some one that raising your compression was good for higher performance. I guess that is not true?

-Chris

 

Lower compression means a loss of power whether you are boosted or N/A. All it does is widen the margin for error so you can boost more without risk of detonation. Another option is running 100+ octane race gas...

There are many things that are good for N/A performance that are a complete for boosted (also nitrous) applications such as:

Advanced ignition timing
Higher compression ratio
Leaned out a/f ratio at WOT (open-loop)



Mike

 

Higher compression when naturally aspirated (no boost) will yield higher horsepower over the stock compression ratio.

Lowering compression when you're boosted allows you to run higher boost levels than would be possible with the stock compression ratio. More boost = more horsepower.

So they both serve a purpose, but it depends on what you're looking to do with the engine.

 

so how do you adjust or change the compression, im not too familiar with that.

 

There are several ways to lower compression ratio. One is to have the head machine down alot within specs. (2) To get a piston with a flatter top dome. (3) Or you can get a thinner head gasket. The 1st option and option (3) are one in the same but (3) is a cheaper option. Research, Research, Research is the best idea. Just know what you what to do, because each one has it's (+) and (-)'s.

 

great thanx for the info.

 

Um.. you just went BACKWARDS. When you decrease the distance between the head and the piston (IE: shaving the head, or getting a thinner head gasket) you RAISE compression. In order to LOWER compression there are only two ways:

1) Get lower compression, flatter pistons (only valid point you mentioned.)
2) Stack MULTIPLE head gaskets together (which I do not recommend.)

Looks like you need to research research research.

 

Please ignore his methods and read my above post.