Whats the limit, how high CR can i go if I have a JRSC 6psi? Would it be better to have higher CR with lower psi or higher psi and lower CR?

 

id say a 8:1 compression would be nice that way you can up the boost on the JRSC. lower with high psi!


[Modified by FuknGSR, 9:44 PM 11/12/2001]

 

Isn't 8.1 a little low? Most ppl I see are doing 9.1:1.

 

Keep the 10:1 compression. JRSC does not follow the rules of forced induction. Just trust me on this one. If you have the cash to lower compression..maybe you just want to get new rings, ITR exhaust cam, valvetrain, and program an ECU to rev a little higher and tune it with the JRSC. It will be crazy!


[Modified by Lee Chun, 8:57 PM 11/12/2001]

 

keep stock compression or 9.5:1 at the lowest. JRSC`s don`t like high compression. That`s why the R`s dont make much power sc`d

 

I dyno'd @ 200.1hp to the wheels on my 2000 ITR w/JRSC@5.5psi

List of mods to come.


[Modified by 2000R, 6:56 PM 11/15/2001]

 

2000 ITR #00-0046 PY
Comptech Ice-box
Comptech intake
Ported T/B, with smaller pulley
JRSC@5.5psi
AEM fuel rail
AEM fpr
Cartech 20005 FMU
AEM cam gears
AEM power steering pulley
Kamikaze header
Stock CAT
Thermal R&D cat back exhaust 2.25"
17" Team Loco 142s in gunmetal
Nitto- 555- 204/40/17
3 pod gauge on A-pillar
JR boost gauge
JR fuel pressure
J&S monitor
J&S Ultra safe-guard
Tinted windows
Have all stock parts.
Dyno wheel HP 200@8400rpm
Best time-13.84@102.45mph

The ITR can make power with the JRSC just takes good tuning.

 

8:1 is too low for a SC.

since the JRSC can't go over 14psi without an intercooler (and there isn't one yet, so 14psi is the limit) I wouldn't even bother lowering compression, but I wouldn't raise it at all either.

heat is what you are trying to avoid, and raising compression increases heat, any kind of FI increases heat.

if you are staying with the stock 6psi setup I would not lower compression as you won't get any gains out of it, but at the same time raising the compression will bring in some problems you don't want to deal with.

 

Time to get flamed. You spent a ton on gadgets to make that power. Plus, it`s not really that much power! You could pull high 13`s w/ a $500 NOS kit. Anyways, I`m not trying to be an ***. If you are happy, then I`m happy.

Good luck!

Ryan

 

how effective would a 50 shot of nitrous be with a supercharger? it would help cool it wouldnt it? or am i way off again?

 

Yea I am happy.
my dyno was like this /
now its like this ------

 

b18c1 + JRSC = 210whp
b18b1 + JRSC = 165whp
b18c5 + JRSC = 190whp

These are all approximate figures, and with a stock JRSC @ 6lbs. Also, with the JRSC, the upper limit that you can push, psi-wise, before you create more heat than you can justify with the HP returns is ~10psi.

For some reason, the b18c1 just like the JRSC the best.

Tom

 

will P&P help w/ jrsc? or how about other mods?

 

i would think the B18C5 would end up with more power than the B18C1 since it has 25 more hp from the factory......

 

nope...dynos show that gsr makes more power w/ jrsc than the itr...

 

One would assume so wouldn't they. Its a good thing we know that it would be a faulty assumption though.

 

i have a theory as to why the itr jrsc setup makes the same, but usually less hp than a b18c1...but i gotta do some more research first before i post it and potentially make a fool outta myself.

Tom

 

Bah! Make a fool of yourself. That way we can amuse ourselves

 

Ok, the reason it seems a JRSC'd R doesnt make as much power as a JRSC'd GSR is actually due to the R's ECU. It literally dumps a ton of fuel up top because the R breathes better stock. The JR kit adds fuel on top of the stock fuel curve and it ends up robbing HP up top on R's. They key to getting an R to make HP is using a different ECU (p28 chipped, p72 or p30) or burning a new fuel curve. Once that is accomplished, I have seen 235whp on a stock kit and 250whp on an 8.5 psi kit.

Dont forget----> high compression+boost = High HP with good tuning

Here is a link to Mike's post on HB laying down 255 on a dyno:

http://www.hostboard.com/ubb/Forum40/HTML/008993.html

 

Type R...no turbo, no jrsc...NOS 120 SHOT....
GSR...turbo is good, jrsc is also good...nos 120 shot...

 

Sis have the same problem. rboosted is making insane power for his car. If only every SCITR made that power...

 

If thats true, why can't you just tune down the fuel via a V-afc or something similar. IIRC the R guys make good power if they have *every* single possible mod to extract hp, and run on the very edge of detonation.

Chris_Turbo, i started writing a post about why I thought an jrsc'ed itr makes not soo good power, but it got to be so ridiculous that i just stopped typing...haha.

Tom

 

Yes the R does dump fuel up top. At about 7000 to 7500 rpms I lose 15 whp then it climbs back up to 200 at redline.