weak vtec
#1
weak vtec
so i built a 95 gsr short block and have a ctr top end, with a 95 gsr vtec solenoid.. vtec comes in about 5500 rpms but cracks really weak and seems to take about 5 seconds to enguage. i hear it and feel it just a little bit, not like firends cars i have been in. also i have the stock ls manifold all the way back to the stock muffler, could this be causing 2 much back pressure and and hindering the vtec?
#2
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Re: weak vtec
What ecu or tune are you running? Vtec shouldn't 'crack, kick, snap' or whatever kids are calling it these days. It should be a smooth transition. If vtec kicks when it engages, that means you have a dip in power right before, that is a bad thing.
#5
Re: weak vtec
well i guess its working fine then, stock p72 obd1 no tuning, ok well then cool i guess i just expected a bit more for a 11.0 to 1 gsr engine... maybe new cams and a header and exhaust are in order. thanks guys. very helpful
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#8
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Re: weak vtec
well obviously your running ctr cams with gsr ecu. the point is that a gsr ecu does not send out enough fuel for your ctr cams..therefore even with the ctr cams your ecu is only running it to gsr specs..i have 01 itr cams in my gsr head with gsr valvetrain and just running a gsr ecu my car felt like crap..but when i got a p28 and chipped it with an ITR basemap "basically an itr ecu" my car was running to its potential...in other words its like running a ls ecu on a gsr motor...
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Re: weak vtec
ding ding ding! Tuning is everything brother and the correct ecu setup could be causing exactly what your talking about
And for the love of God please learn that vtec should NOT crack hella hard homey..that is all gl OP
And for the love of God please learn that vtec should NOT crack hella hard homey..that is all gl OP
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Re: weak vtec
What intake manifold? The stock P72 ECU opens the intake air bypass valve in the stock GS-R intake manifold at 5750, but VTEC activates way down around 4400 rpm.
#14
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Re: weak vtec
what most people think is vtec is actually the secondary valves in the intake manifold opening up. you put an intake on it and you can hear a difference in sound.
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Re: weak vtec
well obviously your running ctr cams with gsr ecu. the point is that a gsr ecu does not send out enough fuel for your ctr cams..therefore even with the ctr cams your ecu is only running it to gsr specs..i have 01 itr cams in my gsr head with gsr valvetrain and just running a gsr ecu my car felt like crap..but when i got a p28 and chipped it with an ITR basemap "basically an itr ecu" my car was running to its potential...in other words its like running a ls ecu on a gsr motor...
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Re: weak vtec
oh my bad lol!!!!!!!! i thought he had a ctr head thats why i thought he maybe put a ls mani but still he needs a tune on a p28 or something else
#19
Re: weak vtec
sorry for my honda ignorance... i have a 650 hp 68 cuda, i know about that one. but im learning.
every "fast" vtec car i have been in "cracked" vtec hard, the fastest one was a 92 hatch with a bone stock h22. cracked hard and pulled hella hard. anyhoooooo i do have a ctr head, but it still does not have a ls intake. its a b16 intake. with a cheapie short ram... can i chip the p72? would that be of any use? what about a cheapie ebay header? better than ls manifold?
every "fast" vtec car i have been in "cracked" vtec hard, the fastest one was a 92 hatch with a bone stock h22. cracked hard and pulled hella hard. anyhoooooo i do have a ctr head, but it still does not have a ls intake. its a b16 intake. with a cheapie short ram... can i chip the p72? would that be of any use? what about a cheapie ebay header? better than ls manifold?
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Re: weak vtec
sounds like u need to read this articale. Read the whole thing or it would make any sense. VTECwas not developedas an instant power gainer like Nitrous it doesnt swich on the power. VTEC was ment to take and help the motor produce a more ever power band across the low rpm up through the high rpm.
http://www.team-integra.net/sections...p?ArticleID=45
http://www.team-integra.net/sections...p?ArticleID=45
#21
Re: weak vtec
i understand how vtec works, thanks.... but what im wondering is if doing any of the header stuff or chiping would help out much, the stock ls manifold seems pretty restrictive. also the rev limiter at 8200 not cool. so would going with a cheapie header and chiping the ecu help much or are those just a waste of money?
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Re: weak vtec
I'm surprised no one picked up on this yet, A GSR block with a B16/ITR head will have a lower CR than a stock GSR. Your CR is now, lower than 10:1 it's more like 9.7:1, assuming no milling or decking took place. That can also be a reason why your car is running like crap.
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#25
Re: weak vtec
nah it was decked and milled and all then went a bit too far so i had to add a shim, never do them at seperate times, or if you do please remember what you took off your head!!!! oops. another mistake.