I have a 2000 Civic Si with a Drag III kit.

With stock internals at 8lbs one tuner got 233whp 178lbs (Dynamic Autosports, CA).. After buildup which included CTR cams, springs, valves, skunk2 im, 66mm tb, sleeved bottom end which includes rods and JE Piston and Hondata my new output is 230whp and 165lbs @ 12lbs (Import Builders, CA). Now i did lower my CR and used 2 different dynos.

I am running a 2.5 in. downpipe > stock hollow cat > Greddy Evolution Exhaust (2.25 in.).

Why do you think my new numbers are so low?? Lower CR.. Difference of Dyno's.. CTR cams have too much overlap... hollow cat creating turbulence??

Also What should my new compression ratio be given the below info (w/stock crank)?

Thanks For Any Help...

_____________________
Civic Si Piston Specs
Stock 10.2:1

New Pistons
Piston Part # 176450
Motor Type Acura 1850cc
Bore 3.209
Stroke 3.433
Rod Length 5.429
Flat Top
Comp. Dist 1.81

 

compressino ratio plays a big part in power....as you found out. It sounds like you didnt increase the bore (you could have gone to 84mm).

Your new setup will make more power..just have to turn the boost up!

I bet you will gain like 15hp if you just drop the exhaust. 2.25" is SMALL.

liam


Modified by liam821 at 3:15 AM 7/8/2003

 

Drop the cams for some GSR's

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by liam821 &raquo;</TD></TR><TR><TD CLASS="quote">compressino ratio plays a big part in power....as you found out. It sounds like you didnt increase the bore (you could have gone to 84mm).

Your new setup will make more power..just have to turn the boost up!

I bet you will gain like 15hp if you just drop the exhaust. 2.25" is SMALL.

liam
Modified by liam821 at 3:15 AM 7/8/2003</TD></TR></TABLE>
That's what I was thinking. YOu need atleast 2.5" but I'd go with 3" just because of the DOHC.

 

I don't think its yor compression dude...I have 9:1 and making close to 300whp at 12psi with a 2.25" dp ...I say its your fuel...what kind of fuel setup do you have?

 

I'm going with the cams, i've switched from ctr to gsr in an integra and it felt way better! This was before we had the dyno so I don't have any numbers. The compression will play a role too, but mainly the cams.

 

I have a 98 ITR which are CTR cams as well...no such problem...but they were tuned for it...

 

This may be complete bs, but it also could be the case that Import builders's dynojet produces lower numbers than Dynamic. Example: Two type-r with same exact setup, one dynoed at 195 at Dynamic Autosports and the other one dynoed at 175 at Import Builders. Go figure.

But I would agree that something is wrong, you should at least be getting 250 @ 12 psi even with lowered compression.

 

MiraiZ - My fuel setup is: in tank 255, AEM fuel rail & Filter, 440 inj. , Vortec FPR


How low is my compression now?

If you think the cams might do it then what GSR cams do i get .... do you think i will still pass smog when i convert back to N/A with the cams..?

 

Just get GSR intake and exhaust cams. I don't think there is different kinds??

 

Anyone know my compression ratio now?

 

How did you lower your compression?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1CleanSi &raquo;</TD></TR><TR><TD CLASS="quote">MiraiZ - My fuel setup is: in tank 255, AEM fuel rail & Filter, 440 inj. , Vortec FPR


How low is my compression now?

If you think the cams might do it then what GSR cams do i get .... do you think i will still pass smog when i convert back to N/A with the cams..?</TD></TR></TABLE>

So you are running FPR and 255LH pump...taking stab in the dark, but you might be rich...check your plugs...do you back fire a lot?

Also, the cams are up to you, but my cams are great!! Totally stock and no problems...but before tuning, I did have bad hesitation a VTEC point...once it got over it....the car tookoff like a rocket....now its just pure rocket and it sounds awesome too.

I would consider an AFC hack or stnd alone before I do the cams...just my opinion though...not an expert...

 

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

So you are running FPR and 255LH pump...taking stab in the dark, but you might be rich...check your plugs...do you back fire a lot?

Also, the cams are up to you, but my cams are great!! Totally stock and no problems...but before tuning, I did have bad hesitation a VTEC point...once it got over it....the car tookoff like a rocket....now its just pure rocket and it sounds awesome too.

I would consider an AFC hack or stnd alone before I do the cams...just my opinion though...not an expert...</TD></TR></TABLE>

He is using Hondata.

 

whats your timing set to?
timing multiplier?

no matter what your compression is now, it should be making way more power than that!

 

sounds weird. Could be timing...

 

go back to b16 cams friend had a GSR did the same with itr cams it did 210whp on dyno at drag wars jus recently then we took cams out put b16 cams thats all he had to use he traded his factory gzr's off but he actually picked up 13 more hp with the b16 which we later dynoed at a some here locally. oh and if you do take off might wanna try thicker head gasket stded head bolts and dual valve spring with reatiners. right now im fighting a losing battle with a b16 reacting badly with boost it has max rev kit it only runs high 14's but i think it in wiring

 

i wouldn't worry, sell the ctr cams, and buy a 3" dp and exhaust. With a straight thru muffler, turn up the boost and retune. im sure you will be better off then your old setup...