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Discussion Starter · #1 ·
A company over here is offering +.5 oversize forged pistons that give a 11.8:1 CR is this too much for road use ? What are the advantages and disadvantages of this ?

I finally have my SR20DE in bits on the bench, I am wondering which way to go with. Any suggestions would be greatfully received. I am thinking of flowing the head and block. I intend to use SR20DET con-rods and forged pistons, as mentioned above. Is it worth the expense of going "all Steel" on the bottom end ?

I would really like to use US companys to buy my products because it seems only to be the US that gives a **** about tuning these motors.

Thanx

Gazmo1

[This message has been edited by Gazmo1 (edited 04-13-2001).]
 

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porting is nice as well as extrude honing heads and manifold also port match. smoother more efficient engine is what you'll have. I don't know much about compression ratios if that will work or not .good luck what company is this you're talking about?

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91 SE-R,10:1 comp.pistons,balanced &blueprint rebuild.comp.4angle valve job,extrude honed heads/intake manifold,No emissions.crap,RC TB/MAF,nismo cams,UR pulleys,stillen4-1 ceram.header,nismo/centerforce dual fric.clutch,PR CAI,2 1/2 test pipe,mandrel 2 1/4 superturbo ex.,and a whole bunch of other goodies! boost is in the works ,hell yeah 3:16!
 
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Discussion Starter · #3 ·
funny, i also have a ?? on CR. i know by changing piston, etc you can acheive a higher CR. what about milling the head like 0.030 to boost it up a tad? would that be detrimental? valves hitting things and heat a big factor?
 
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Discussion Starter · #4 ·
The company is a UK company called Siliva Enginnering. I pretty sure they are made by somebody else and marketed by them as there own.

Another question, How do you calculate a CR ??

Gazmo1
 

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<font face="Verdana, Arial" size="2">Originally posted by 2000SE:
what about milling the head like 0.030 to boost it up a tad? would that be detrimental? valves hitting things and heat a big factor? </font>
Don't mill the head!! It will throw the cam timing off and does some funky voodoo to the flow charateristics. 11.8:1 is really high, comapare, stock usdm se-r/nx2k 9.5:1, jdm primera 10:1, most of the fully built N/A monsters are about 11-11.2:1 but have a ton of other work done to them. To run over approx 10.5:1 (or so, I forget the limit) you'll need a JWT high comp program. The firing gets sssoo violent that it triggers the knock sensors!! There are alot of other variables involved, if you're serious let me know.

Blair
 

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for refrece on cr the btcc (former) primera used a 14.5:1 cr in it, but it was all turned around, intake manifold in front, exhaust manifold in back, I have a 4-5 page article on it from Race Tech a few years ago.
 

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<font face="Verdana, Arial" size="2">Originally posted by Gazmo1:
A company over here is offering +.5 oversize forged pistons that give a 11.8:1 CR is this too much for road use ? What are the advantages and disadvantages of this ?

I finally have my SR20DE in bits on the bench, I am wondering which way to go with. Any suggestions would be greatfully received. I am thinking of flowing the head and block. I intend to use SR20DET con-rods and forged pistons, as mentioned above. Is it worth the expense of going "all Steel" on the bottom end ?

I would really like to use US companys to buy my products because it seems only to be the US that gives a **** about tuning these motors.

Thanx

Gazmo1

[This message has been edited by Gazmo1 (edited 04-13-2001).]
</font>
I got 2 words for you, Mike Kojima. Check the SE-R.net for his 11:1 motor.
 
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Discussion Starter · #8 ·
Brian

Can you e mail me the article about the primera engine ?

With regard to the pistons, What types of forged pistons are available on the US market ? Like ones where the CR isn'r stupid.

Gazmo1
 
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