Losing Power In Vtec

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sleeperls93

Senior Member
My car is really running sh*tty in vtec; it gets really loud in vtec, louder then usual, and it feels like it's losing power??My engine is 16k old, is this signs of a neede valve adjustment??
Actually, there's a substantial loss in power; I was doing some "comparative acceleration" tests with my buddy's nissan sentra spec R, which I usually out accelerate with ease in vtec, but this time, my teg didn't go anywhere in vtec and the spec R out accelerated me! This has me a little worried, is it this bad when a car is in need of a valve adjustment, or could ther be something wrong with the vtec system??I'm going to get a valve adjustment sometime this week, and a compression test while I'm at it...It's an lsvtec conversion btw....
 
if the valve lash is really bad, your valves will not open as much delivering less air/fuel hence delivering less power.

so to answer your question, yes, a valve adjustment might be your problem.
 
I hope that's what it is...I was told that the power loss shouldn't be that noticeable if i just needed a valve adjustment....it's pretty bad in my opinion, when normal, once the car reaches vtec range it races to the revlimit; now, it just gets super loud and takes foerever to get up there, extremely noticeable power loss. Driving under 5k rpms, it's barely anything noticeably wrong.

Let me tell you guys my set-up so you know what I'm working with: Lsvtec conversion b16a head, eagle rods, 11.0:1 cr je pistons, block guard crower 63402a vtec cams, and crower dual valve springs and ti retainers; oh and skunk2 cams untuned...Thanks for the reply.
 
Originally posted by sleeperls93@Mar 3 2003, 11:09 AM
Let me tell you guys my set-up so you know what I'm working with: Lsvtec conversion b16a head, eagle rods, 11.0:1 cr je pistons, block guard crower 63402a vtec cams, and crower dual valve springs and ti retainers; oh and skunk2 cams untuned...Thanks for the reply.

how can you run the 64302a cams as well as skunk 2 cams??? Quad cam? didnt think so... prolly a typo on your behalf

i would suggest you get your car tuned... if i ever have a doubt about my car i always get it tuned... and i haven't had too many problems since then, except for fuel pressure but i adjusted that myself... so my suggestion is to find a good tuner in your area and get it tuned..

if your in the so cal area i know a few people to recommend.
 
one more thing, what kind of oil are you running? and did you check the oil level lately?

thats one thing with my LS/VTEC... i burn a shit load of oil so i change it every month and a half if i drive it on the street. and as of right now its not registered so i change it right before i run at battle or IDRC... so check your oil also... i experienced almost NO VTEC when my oil was low cause somebody i let work on it used shitty oil and it burned up in like a week!!
 
i had a similar problem with my car, it would get loud in vtec, a strange loud, louder than before, and a total loss in power, it felt like i was making more power at 3500 than at 6000rpm. the cause? a bad catylitic converter, somehow it broke up inside and was clogging my exhaust system. easy way to check is pull off your cat at the header and hold up the pipe with something and drive around on an open header and see if the problem still persists.
 
Hey thanks for the responses! What I ment was skunk2 cam gears, sorry about that, lol. So the only person with a similar experience found that it was the catalytic converter? Wow that's kind of weird...? I hace a catco cat btw, I know there not that great...Damn, how can it be the cat? I'll have to check it out...

Oh, and I check my oil every single day....
 
Originally posted by sleeperls93@Mar 3 2003, 02:28 PM
Damn, how can it be the cat? I'll have to check it out...

it was because it was causing a TON of backpressure in the exhaust system, so the exhaust had a real difficult time trying to get out, probably going back into the motor :p i thought it was strange too, until i thought about it... but, easy check to do.
 
Cool, thanks alot fellas, I'm going to get it checked out tommorrow, I 'll let you guys know how it goes; Hopefully, I could find a high flow cat out there, without buying the oem one... :)
 
Originally posted by sleeperls93@Mar 3 2003, 05:16 PM
Cool, thanks alot fellas, I'm going to get it checked out tommorrow, I 'll let you guys know how it goes; Hopefully, I could find a high flow cat out there, without buying the oem one... :)

ya, last time i checked an OEM cat cost like $1,400.00 !!???? :blink: crazy huh? the guy at the honda parts department said it was because Honda doesn't like to sell cat's, wtf?? check to see if its the cat first though, could be something else... let us know what you find.
 
I already ordered a cat on ebay, carsound, but i wanted tu gut out my current cat until the new one arrives...Is it easy to gut out a catalytic converter??
I'm hoping this is the problem, because my build-up is basically new, with all new parts, and the cat is over a year old and it was pretty cheap, so hopefully that's all it is :mellow:
 
Originally posted by sleeperls93@Mar 4 2003, 12:18 AM
I already ordered a cat on ebay, carsound, but i wanted tu gut out my current cat until the new one arrives...Is it easy to gut out a catalytic converter??
I'm hoping this is the problem, because my build-up is basically new, with all new parts, and the cat is over a year old and it was pretty cheap, so hopefully that's all it is :mellow:

all you have to do is take off the cat, spray it with water and start stabbing it with a screwdriver... it works believe me haha... the honeycomb is really thick so you'll be stabbing for awhile, keep on saturating it with water or another liquid if you choose...

but soon enough you will have a completely hollowed out cat... there are something like 6 layers of honeycomb blocks
 
Originally posted by sleeperls93@Mar 3 2003, 09:18 PM
I already ordered a cat on ebay, carsound, but i wanted tu gut out my current cat until the new one arrives...Is it easy to gut out a catalytic converter??
I'm hoping this is the problem, because my build-up is basically new, with all new parts, and the cat is over a year old and it was pretty cheap, so hopefully that's all it is :mellow:

well, you would have wanted to check first before ordering a new cat.
 
Very true b16, but it gives me incentive to go with that 2 1/2" custom exhaust that I want; If it's something else,something terribly expensive, I think I would probably get rid of the car cause it would be cursed...Everything is new on the motor. ;) thanks 2litereg
 
Vtec Wireing? i had a proble with the Wireing in my B17A Crx Hybrid what it was a Wire that leads to the Vtec Oil Valve it was Cut and puting that back on got my Vtec runing....
 
Vtec does engage though, if it's not getting the appropriate oil it wouldn't engage at all....and I check my oil levels daily!
 
Originally posted by synergy2636@Mar 5 2003, 09:07 AM
What would happen if your oil pump decided to go out??? or be week? would that stop your vtec??

I don't think it would run... :huh:
 
My baby is back 100%! Thanks for all the replies, and a big thank you to B16 and Delscho of hondavision for correctly diagnosing the problem! The cat was completely stuffed, and now it's completely gutted lol... It sound a little loud now...But beware of catco converters, they are very cheap and unreliable...
 
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