Hey everyone, looking to get my block rebuilt with forged internals. I have owned and worked on many turboed cars but I have never dropped the compression personally. I am looking to make about 300whp. What is everyone's recomendations on brands and comp ratio? Also would you recommend sleeving the block for 300whp?

Thanks in advanced,

Matt

 

Sleeving for 300? Hardly. You can make that on a STOCK block.

 

Ok, so what you are recommending is that I do not need any bottom end work to hit 300whp? At what point do you recommend forged internals? At what point do you recommend Sleeves?

 

For 300 whp you can use stock internals. It doesn't hurt to have a freshly rebuilt motor that has looser gaped rings.

If you are planning to take it apart and build it anyway, you should stay in the 9.5:1 to 10:1 C/R range, this will yeild good off boost responce.

300 whp on stock internals.
500 whp on stock sleeves with forged internals and a good tune.
Over 500 whp sleeves.

 

Alot of people make around 300whp on stock blocks. Id sleeve around 400. If you are intent on building up the bottom end then start with forged pistons. And rods if you have the money but not needed for 300hp.

 

The stock GSR compression is more than fine; as is the entire engine. Check the health of the stock engine (compression, leak-down, ect) and go from there. A general rule of thumb is to not go over .5mm/0.020" over on the bore though for forced induction setups with stock sleeves.

 

Thanks everyone. I think ill just boost on stock block for now, if leakdown and compression is good ( I hope so with a nearly new motor). If not I will probably sleeve and go forged internals, I mean if i take it apart might as well go big or go home right? Any recommendations on turbos for my power goals on stock internals?

 

If you insist on having forged internals, 9:1 is a pretty common standard. Its an off the shelf readily available piston that can make gobs of power.

 

stock compression is perfect.

 

yea anything between 9 and 10:1 will be fine. for the turbo i personally love a 57 trim on a stock block gsr/b16. ive tuned a handfull of them over the years and have always been impressed

 

yup stock tough

 

This is always a beaten up topic... your going to get both sides here. Couple factors to condsider when choosing a compression (static)... Fuel being used, Tuner, type of driving car will see. Personally I like stock compression.... hell is free power.... but higher compression requires better gas (and good consistance between fill-ups), and most importantly a good tuner. Conversely, lower compression gives you more flexibility for **** gas and shitty or just average tuner. However the cost for this is that the car will be a bit sluggish out of boost and you will need more boost pressure to obtain the same power level as with a higher static compression ratio.

hope this helps.