alrighty, the setup is a jdm gsr in a 99 civic ex coupe....... mods? cm stage 4, xact 12.5lb flywheel, and a generic intake. also, the car weighs just over 2200lbs.....

i used to have a b16a2 in the car, and the b18c pulls much harder in the low and mid ranges..... there is a solid boost in acceleration at 4500 (vtec) and again around 6200 (secondaries). up to 7000 rpms this motor has justified the swap...........

but that's where my concerns begin...... the motor/car will just not pull past 7000 rpms.... most noticeably in 3rd gear and up. it's as if i hit an aerodynamic wall everytime i get to this engine speed. on the other hand, when i upshift i can feel the car jump forward as the power is delivered once again.....

now i'm sure the stock 2.25" exhaust i have is killing my exhaust flow, but could there be any other issues that would cause the motor to choke this way? might my stock ex fuel pump be too weaksauce to supply the jdm motor? i've already made plans to eliminate the exhaust restrictions, but i'd like to know if i may have missed something else........ any help would be appreciated.


Modified by Team 4R at 8:17 PM 2/4/2004

 

ECU maybe? That's weird. Good luck.

 

obd2 jdm p72.... i suppose that could be a part of it. i'll be moving to the aem ems in a month or two....

 

JDM ECUs have limiters

 

i realize that....... but not at 7000 rpms in every gear?

 

I was told that the GSR fuel pump is much larger (as far as flow/hour) than any of the pre-1999 civics'. It very well could be that you need a better fuel system to get all of the high end the GSR motor is capable of.

 

walbro 255 lph is on the way... i hope that and the new exhaust setup completely fix the problem....

bump for any other ideas.

 

first off how the hell did you get a coupe to way 2200 pounds?

Also what does it fell like when you hit 7k? is it like a rev limiter or is it just running out of fuel? my guess would be fuel starvation run it up to there a few times once you hit that mark back off the pull your plugs and see what color they are.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Archidictus &raquo;</TD></TR><TR><TD CLASS="quote">I was told that the GSR fuel pump is much larger (as far as flow/hour) than any of the pre-1999 civics'. It very well could be that you need a better fuel system to get all of the high end the GSR motor is capable of.</TD></TR></TABLE> well even so arent the injectors both 210cc??? so it is still getting the same flow of fuel isnt it??? i dont know if it makes a big difference but are you running premium gas??? i know my usdm requires premium maybe the lower octane is the problem

 

bump ...for you.. i want to know also

 

bump again... why would his fuel pump be a problem if the injectors on an ex and a gsr are the same cc's?? wouldnt it be the same pump???

 

thanks for the bumps....... the fuel pump in my ex has a lower rating than a gsr fuel pump. i think it's 140lph versus......... uh, i don't remember just now. i think it was like 190 lph.

i am using 91 octane gas. and i doubt it's a bad batch because it's been running like this for a month and i've filled the tank in socal and norcal.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99blackcivicSi &raquo;</TD></TR><TR><TD CLASS="quote">my guess would be fuel starvation run it up to there a few times once you hit that mark back off the pull your plugs and see what color they are. </TD></TR></TABLE>

if it's fuel starved my injectors will be white, correct? i'll check them shortly....

 

could have to do with your oil pump or transmission fluid.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99blackcivicSi &raquo;</TD></TR><TR><TD CLASS="quote">first off how the hell did you get a coupe to way 2200 pounds?
</TD></TR></TABLE>no ****.. i thought my 97 EX was light.. 2200 is unreal unless that bitch is completely stripped

 

i didn't take it to redline, but the plugs do have a whiteish tint to them....... hopefully the new fuel pump will fix this right up.

 

sounds like your running lean,

also to the guy above i don't think that GSR injectors are the same as Ex injectors, i think GSR are 240 and Ex are 210 i could be wrong though.

 

yeah i know for a fact that the stock gsrt and ex injectors are the same... im think they are 210cc .. might be 240cc.. but i am 99.9% postive they are the same cc's... cause i was told i am ok to swap my ex injectors into my gsr motor since they are both obd 2... but back to this guys prob... it def sounds like the fuel pump..

 

Ok my bad they are all 240cc