I thought some of you guys may be interested in a quick little comparison regarding my recent change in pistons. I was running my stock ITR motor with my turbo setup at 7.5 psi with "ghetto fuel management"...12:1 FMU, inline pump, stock injectors, missing link...I made 282whp and 198 torque believe it or not with an open DP and only 7.5 psi. Now I swapped in some Arias 9.0:1 pistons, Inlinepro blockguard, new OEM headgasket, walbro intank pump, and am running around with 7.5psi with the same turbo setup and the new compression after breaking in the new pistons slowly. I'm awaiting Hondata and I'm putting the car on the dyno as is and if the air/fuel is not safe I'll park the car and wait for Hondata before driving it any more right now.

The Comparison:
The 9:1 Compression definately feels torqueless down low, and the turbo appears to spool a few hundred RPM's later then before. But up top, the car seems to pull noticeable harder for some reason. That may be due to the slightly slower spool and/or the slightly later spool may give the appearance that the top end is harder then it really it. But it does indeed feel very strong above VTEC, almost stronger then before. Overall I'm happy with the cars performace even with low boost and low Compression. I just can't wait for Hondata to get here and get her tuned for some real boost
Mark

 

this would be very interesting for alot of people, there was a good topic just recently on compression#'s. Only inaccurate form of comparison is that ull be runnign hondata with new setup compared to fmu setup, so it will be hard to compare. Maybe you can dyno once before you tune hondata, that will 1) show everyone difference in dropping 1.6 points and also show you how much power you gained from hondata .

 

i agree.... you should dyno that thing before you install the hondata.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by azboy &raquo;</TD></TR><TR><TD CLASS="quote">i agree.... you should dyno that thing before you install the hondata.</TD></TR></TABLE>

I am, it's going on the dyno with a wideband tonight or tomorrow morning to make sure the current FMU setup is safe for another week untill Hondata gets here
Mark
I'm really curious to see what it's putting down right now.

 

I very interested to see what it does with the new pistons and fmu, be sure you post your numbers.

 

Keep us informed!

 

yeah definately interested too

 

im very interested.... you can put more volume of air in each stroke there fore more power

 

I'm highly interested in the numbers too.

I'll be running the factory 10.6:1 on mine until my bulletproof block is built. Anyhow, I'm hoping to hit around 280whp with standalone and fuel system on a custom kit.

Even with the bottom end being built, I was going to throw in some forged 10.0:1 pistons with stock bore.

 

ill be running 10.7:1 and will post my results.

 

this has do to with the difference between dynamic and static compresion ratios etc.. there is a great post about it, i think labeled "high compresson low boost, low compression high boost" or something to that effect.

 

Ok, well I threw the car on the dyno with the same amount of boost that netted me 282whp and 198 torque, at around 7.5psi. With the new compression, I got 231whp and 169 torque. So with the drop from 10.6 to 9.0 I lost roughly 50whp and 30 ft. lbs of torque. Overall, I was actually pretty happy with that. I just can't wait for Hondata to go in and get her tuned for much higher boost
Thanks.
Mark

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 01ITR#700 &raquo;</TD></TR><TR><TD CLASS="quote">Ok, well I threw the car on the dyno with the same amount of boost that netted me 282whp and 198 torque, at around 7.5psi. With the new compression, I got 231whp and 169 torque. So with the drop from 10.6 to 9.0 I lost roughly 50whp and 30 ft. lbs of torque. Overall, I was actually pretty happy with that. I just can't wait for Hondata to go in and get her tuned for much higher boost
Thanks.
Mark</TD></TR></TABLE>


wow, thats a big loss from 1 compression point

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by T3T495GSR &raquo;</TD></TR><TR><TD CLASS="quote">


wow, thats a big loss from 1 compression point</TD></TR></TABLE>

its actually 1.6 points which is huge...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MotorMatrix.com &raquo;</TD></TR><TR><TD CLASS="quote">

its actually 1.6 points which is huge...</TD></TR></TABLE>

Thanks for straightening that out, you beat me to it
Mark