Power Hesitation At High RPMS

Nd4SpdSe · Post by **Nd4SpdSe** » August 29th, 2005, 8:33 am

Yesterday at the GuelphRacing meet, I gave 2 Mx-3'ers a quick spin in my ZE. When accelerating, it seems to sit at 6500rpms for about a second. I noticed it the first time, but I though it may have been maybe my tires spinning, but I didn't feel anything in terms of torque steer or any noise resulting of tire spin. I gave another MX-3'er a quick spin on the same road and noticed it again. On the way home, we were crusin' back, i decided to giv'er, downshifted to 3rd (w/rev matching btw) around about 80km/h and floored it, and it actually did it again, so I doubt it's tire spin (as much as I would like to think so). This may be apart of why my car isn't performing as well as I would be expecting it to on the track. Would anyone have any ideas?

DavidOS · Post by **DavidOS** » August 29th, 2005, 9:53 am

gearing in the tranny.
could also be clutch./flywheel related.

Nd4SpdSe · Post by **Nd4SpdSe** » August 29th, 2005, 10:22 am

DavidOS wrote:gearing in the tranny.
could also be clutch./flywheel related.

I've been guessing that maybe it's clutch/flywheel, but what do you mean by the gearing in the tranny?

stereoking15 · Post by **stereoking15** » August 30th, 2005, 6:59 pm

it almost sounds like clutch slipping but with it stalling (sitting) at that rpm and not moving (gaining in rpm) it could be a dead spot in the distributor

Slammed6 · Post by **Slammed6** » August 30th, 2005, 8:05 pm

no to scare you or anything, but i noticed my KL-ZE doing this before i broke a retainer in the front head....And now that i think about it the car pulled decent until right around 6500 and then it would go past that but it did kinda pause there for a sec.

I'm sure he would notice the clutch slipping more from a hard shift from 1st to 2nd gear, if it grabs hard and spins the tires i doubt that the clutch is slipping at that specific RPM.

DavidOS · Post by **DavidOS** » August 30th, 2005, 9:22 pm

Nd4SpdSe wrote:
DavidOS wrote:gearing in the tranny.
could also be clutch./flywheel related.
I've been guessing that maybe it's clutch/flywheel, but what do you mean by the gearing in the tranny?

our gearbox gears are built to rev a certain way at certain revs, and power tapers off at high revs as the gears cannot handle to much more and are built to handle a certain rev limit.

fieromx3 · Post by **fieromx3** » August 30th, 2005, 9:29 pm

our gearbox gears are built to rev a certain way at certain revs, and power tapers off at high revs as the gears cannot handle to much more and are built to handle a certain rev limit.[/quote]

is this the same for the automatic tranny as well? cuz when im racing after about 6500rpm the power just dips right down so much. i was thinkin it does this cuz the engine supposably makes max power at 6500rpm so i thought thats y it loses power after that.

Nd4SpdSe · Post by **Nd4SpdSe** » September 3rd, 2005, 9:20 am

Well I went to Cayuga last night and it happened again on my second run, but this time it was at about 5000rpms in 3rd gear, again, just sat there for a second or two. I had the car cool down for a good hour and a half (waited for Trevor and a mustang snapped his axle, they had to clean up after it) and the car has just gotten back up to temp when i got to the line, so it was running at it's best for the night, the other times the car was hot after driving on the highway and idling waiting for the race.

I don't understand how the gears in the tranny could cause this, they are all connected together, the only thing that allows give is the clutch. The way I'm understanding your explanation, it's like the gears slip, which is a concept i really can't grasp unless their something critically wrong with the tranny.

Ateana · Post by **Ateana** » September 4th, 2005, 8:01 pm

sounds odd perhaps your coil? i had that happen right b4 my coil went in my bp .... i just got my other car so im not certain what problems arise in the k series engine

mitmaks · Post by **mitmaks** » September 4th, 2005, 8:50 pm

sounds like your clutch is slipping

Slammed6 · Post by **Slammed6** » September 4th, 2005, 9:14 pm

Everyone says clutch!

Its easy to see if its that. Drive the car in 5th gear, rev the car to a good rev like 5-6000 RPM and dump it while your rolling. The clutch should grab and the car will stay at a steady RPM. If the RPM's go up and the car is still at that same pace, then its the clutch. Easy

Nd4SpdSe · Post by **Nd4SpdSe** » September 9th, 2005, 1:21 pm

Like on the highway or at low speeds?
(more likely highway, right?)

I think I'll try that today.

Slammed6 · Post by **Slammed6** » September 9th, 2005, 1:24 pm

Like on the highway or at low speeds?

Go to about 50 MPH and do that

Nd4SpdSe · Post by **Nd4SpdSe** » September 9th, 2005, 1:33 pm

Cool, I haven't checked this thread in a few days, I could have sworn there were no replies...appreciate the inputs.

Honnestly, I would like it to be clutch, but it sounds like it's working backwards, I would have though if the clutch was slipping, if i was racing at the track, it would redline prematurely instead of standing still (however, I'm in no way a clutch expert) but I'll give the highway drop a try

Slammed6 · Post by **Slammed6** » September 9th, 2005, 1:36 pm

Honnestly, I would like it to be clutch, but it sounds like it's working backwards, I would have though if the clutch was slipping, if i was racing at the track, it would redline prematurely instead of standing still

It would...thats y i said it really doesn't make sense to stand still. If a clutch slips the RPMS would redline fast.