Somesthing is seriously wrong.....

[HIGDON]

Something is seriously wrong.....but I don't know what

Ok, it's been an ongoing quest to get my car to run even "normal" times. I put the stock meter back in due to the fack that the car was detonating at high RPM, namely at the top end of the track and I've replaced the fuel filter(normal service). I went back to the track, same weather(hot and humid) and it wouldn't run any better, the MPH is low(89-90) and the timeslips are in the low 15's. I, as well as the other guys I've talked to think the car is hurting big time on the top end. I can't seem to figure out what could be causing the car to be running so flat? It drives fine and seems to pull around town just fine. Does anyone have any ideas to what I can look into to help solve this problem? I know it's kinda vague but there isn't any real symptoms other than it's slow. I would like to have this straightened out before I do my headswap. . .Lemme know what I should check (it's probably something simple and stupid).

 

[twogts4us]

When I yanked my C&L MAF and put the OEM back in, I swear it was almost a week before it ran right. The first few days it ran OK, but it seemed to be down on power, especially when initially stomping on it. Now, 8 days later, it feels at least as stong as it was with the C&L MAF.
But your problem seems to be different...loss of top end.

 

[bull8t]

that sucks man, maybe you need a good tune??

 

[Jackie Chan]

so you are saying in horrible racing weather your car is running low 15s 90's with only gears and a little exhaust work. Calculate the density altitude and see what your times correct to before you jump to any conclusions. If the weather is really that poor, your car just might be fine. My car is a good .3 off right now in FL

 

[HIGDON]

Best run was a 15.40 @ 90. My DA corrected time is 14.94 @ 92.57. Is a 14.9 too far off pace?

 

[Jackie Chan]

I personally am not a very knowlegeable guy about npi timeslips

 

[JohnyD05]

I dunno what time cars of your year usually run,

maybe u need a little practice at the drag strip.

how bout have u done spark plugs, and spark plug wires and stuff?! just basic maintnance.
how do you lauch the car and at what RPM?
whats your 60 foot time?! you have drag shocks so i would think you could launch pretty hard.

other than bring it to a dyno see what kind of power its making?! if its way off bring it to a garage and have it looked at.

 

[GinoGT]

Hot and humid + Non-PI heads =

If that's a 14.9 corrected for DA, I would imagine that sounds about right. NPI heads =

We need more details on the run. 60's, any tire spin, were you powershifting, etc.

 

[padge]

I recently had a similar problem. I have NO top end power basically and the engine pings under high RPM. I took it to the dealer and they first thought MAF sensor. Tried that, didnt work. What actually was wrong is that I bottomed out on a bad road and dented the **** outta my exhaust piping (specifically one of the cats). It pushed the insides of the cats to my mufflers and sort of plugged them up causing a lot of back-pressure (4 lbs instead of 1lb). My car drive around town just fine as well. I'm getting my new exhaust put on this week, I can't wait!

Hope this helps some.

 

[HIGDON]

Well, even when it's cool around 4-5 in the morning I'll take it for a spin and it still feels a bit flat. Thanks for all the suggestions. I'm going to check the plug gaps, wire resistance, fuel pressure, and go over every connection(vaccuum) on the motor tomorrow. I'm just trying to beat this to death before I take it to the dyno to see if there is anything really fubar. I guess I was hoping someone else had this occur and I could have a possible culprit.

 

[COramprat]

Hot and humid + Non-PI heads =

If that's a 14.9 corrected for DA, I would imagine that sounds about right. NPI heads =

We need more details on the run. 60's, any tire spin, were you powershifting, etc.

At the risk of starting a war I don't think the problem is the heads. More proof is coming daily that the intake is the culprit.

Anyway, my car is starting to feel real sluggish too with the rise in temp and humidity. I haven't been to the track but you know your car and can tell the differences, even subtle ones, so it's not just you.