I went out today to see how my car is doing doing in 0-60, I only drove about 150 miles since the 5 months winter storage, so maybe it has something to do with it…. anyways, the car feels quite strong at the bottom end, but once its above 3000rpm its not very powerful anymore.
I used a stop watch and it might not be all that accurate but it should at least give me a good idea. I’ve done about 10 runs and the best was 8.5 !!! WTF is wrong with my car ?? any ideas please
Thanks
Alex

 

There's probably nothing wrong with your car. My 2.8L went 0-60MPH in 11.***, and that was with a slipping tranny.

135HP and 160TQ

 

tune up is wha i think it is.
my car was doing it in 9.4 and running the 1/4 in 16.7@82 and then i did these following things-
MSD super conductor 8.5mm wires
MSD GM Blaster Coil
MSD Cap + Rotor
NGK Irdium IX Plugs
new fuel filter
had my injectors cleaned and tested and flow matched.
K+N air filters
and that alone took me to 15.2@89
then with replacing my broken panhard rd and twisted Lca's and my broken MAF i took her down to 14.85@91, thats what my problem was, in need of a tune up really bad.

 

I've allready done
new plug wires
new Cap + Rotor
new Plugs
new fuel filter
K+N air filters ....
the only thing that I haven't replaced yet is the O2 sensor ? Do you think that could cause that problem ??

 

That might be it then. Either that or your obvisouly not getting gas or a spark. So the O2 is probabbly it.

 

An 02 sensor would hinder performance THAT much?

 

My Jimmy ran so rich with the old o2 sensor that I got 13mpg. After swapping to one of my spares, I jumped up over 20mpg. Running that rich didn't even throw an SES code.

But timing your 0-60 with a stop watch is pretty inaccurate. Combine that with the fact that it's a 305 auto convertable with a peanut cam and sh*t rear end gears, and an 8 second 0-60 may not be unrealistic, especially if your launch isn't perfect.

But... if you haven't changed your o2 in a while, you should do that anyway. Those generally should be changed around every 30k miles even though nobody does it. If that doesn't help, then you might need to get to the track and get some real times to see what's going on.

 

Damn! ::goes to parts store::

 

i don't kow nething bout the o2 sensor but i know my car runs a little rich and i'm gonna replace it when i do my headers

 

could a bad o2 sensor really scew up performance as bad as in my case ??
could it also be a bad TPS sensor ?

 

I have my doubts on the oxygen sensor. I think that it is not used at wot.

Ben

 

Correct, O2 is completely ignoredby the ECM at WOT. This is probably not the source of your woes.

 

Man it could be a whole list of things.

When my old vert was sluggish all of a sudden, it ended up being the ignition module.

 

Same here, my car was actually backfiring under load last summer. It felt at times as if it had no power at all. I replaced the ignition module and it quit.

 

Hi everyone i'm kind of new here, i have the same problem too after 3000rpm the car is cr@P anything below it push petty good. i just have the car for 2weeks, is 89 iroc 305 with 5sp. 50min ago i just race my friend's stock LS integra, beat him from 1st & 2rd after that he pull away petty hard i'm really mad right now too > we race 3 times me = 0 my friend = 3
i'm still young right now don't know much about car problem.

 

Or english? lol

 

Hey i wasn't born in US and still learning English so i think you should give me some respect atleast i didn't go to some dealer and got myself some civic or maybe a neon

 

Hey i wasn't born in US and still learning English so i think you should give me some respect atleast i didn't go to some dealer and got myself some civic or maybe a neon

 

I kind of wondered if English was your first language. Also, if you dont know what lol means, it is laugh out loud. It meant that my response was in kind of a joking attitude. Dont take it personally. I was just messing around.

Ben

 

If it is the ignition module wouldn't I be having idle problems or wouldn't the car just die while driving ?... I test drove it again today and again I could see how slow it climbed upwards from 3000 rpms. Until 3000rpms it pulls really strong.
The weird thing is that the car is runnig good otherwise, just this weird WOT problem

Any more ideas ?

 

do you still have a cat? If so is it before the cutout or after. If the cutout is first, does it act the same with it open?

Ben

 

Yes I still have a cat and its still the first one.... the cutout is behind the cat ... unfortunatly ... do you think it could be the cat ?

 

I have not had the problem before but it seems that from hearing about other peoples problems that you loose a ton of high end power when you have a pluged cat. I was just taking a guess so I really dont know if thats it or not.

Ben

 

Is there a way to check if its plugged ?... I already looked if it would glow after a long ride, but nothing... it also doesn't stink.
What could be hint though is when i went for emissions 3 weeks ago I failed due to having way too high CO and NOx readings... Back then I thought this was due to my advanced timing, but now it looks like the cat may be the problem. what do you think ?

 

my bad

well i tell this guy at my work about losing power after 3000rpm he said it could be from bad fule pump or need to replace the ignition.

 

IROC VERT

You can check plugged cat by measuring backpressure before cat.

 

The problem is you are running a 305..LOL.. ..That isnt such a bad time....my 4rth gen LT1 runs 0-80 in 9 sec..you have a pretty much stock 305..those # are common.

 

alex...

I don't wan't the tell you this... well look at the sig

the 8.2 is constant even with my 255/50s.... wheal spin

It was timed with one friend abord with a stopwatch...

with the stock rear it would take off like grandma' on a rolator my best compleatly stock was about 9.2 0-62mph (0-100km/h)

 

According to my friend's G-tech I ran 0 to 60 in 6.0s flat on a cool early morning with some wheel spin and him (230lbs-fat bastard) in the car.

He said that it is awesome for a 305 with the mods listed below - without prom tuning.

Anyways, i thought i would share that with you. Sound like there could be something wrong with your 305.

 

a lot has to be considered..weather..humidity..up hill ,down hill ,fuel quality ,tuning. The only night I had the 94 at the track it was 40* and nobody was getting traction...second gear the car was all over the place hence the slower 60' time..in the right condititions Im sure I could pull a faster time...I just wanted a baseline figure before we start any Mods...My 89 I hope will be quicker ..hope hope hope....Just decide what you want your car to do, then work work work to make it do it..

 

here is what ya do...take time to read the artical ..pretty good I think....http://www.chevyhiperformance.com/projectbuild/48158/

 

A plugged CAT makes alot of difference. I know that once my CAT got screwed up my car ran alot different. So I can agree with that.

 

Yeah, I would change the CAT (or get rid of it). My '85 Z had a CAT that was clogged and the car would barely run.

 

Yeah my 305 tpi is faster than that . So i think something is wrong.