I just read a thread you responded to about a poor soul with a blower running fine until he hits 3rd gear under the name 'blower woes'. I was wondering also why mine isn't running as fast as it should be. I can tell from a roll is is amazing power, but it just seems like something is missing ... maybe because I havent had it dyno tuned yet, but also maybe because the tranny is shifting automatically at 5200 rpm? Or could it be the lock up deal like you were talking about? I would love to hear your thoughts....or anybody else's.

Thanks!

 

I didn't realize you can't edit a post and ad an image, so take a look at some timeslips below. I'll hypothesize after you've looked at them.

Willie

 

thank ya kindly, sir!

 

These are very similar runs. Look at my 1/8-mile E/T and mph's. Then look at my 1/4-mile results. Do you think something is wrong with one of the runs? Note: No change between the runs.

 

Here's two more. This time, I did not crop the top of the slip to show these runs were made on the same night. Again, no changes between the runs.

Look how close my car runs to the 1/8-mile mark. Then look at my 1/4-mile mph. Why the huge discrepancy? Note: My 2-3 shift occurs between 79 and 84 mph (according to captured data). That, coincidentally, is very close to the 1/8 mile mark.

Any conclusions?

 

Aside from you beating everyone you ran that night, I would have to say that I think it may be because your torque converter was locking up? I would have to say I find that very interesting - if I am on the freeway and get on it, it feels weak. Could that be torque converter lock up or tuning issues?

 

We all know that acceleration is not linear. If it was, you'd get the same kick in the pants in third gear as you do in second. Just looking at a timeslip tells us this. For one of runs above, I made it to 88.05 mph at the 1/8th. The remaining half produced 103.48 mph. That's a delta of 15.43 mph. So it is normal for a car not to feel as strong on the top end as it does in the bottom. Aside from this fact....>>

What I find interesting in the results above is that "something" was causing my car to run slower from 80 mph and above. Because my 1/8th mile times and mph were the same, I could only conclude that the engine itself was not to blame -- that it could not run any different in third gear than it does in first or second. Something was causing a load that slowed the car down ~10 mph.

Reviewing my scanned data showed my converter was locking up some of the time. No one, including myself, knows why this was occuring. Be that as it may, I installed a torque converter lockup disable circuit at prevents lockup at ~4.30 TPS volts (adjustable), regardless of what the ECM commands. Since that time, I have not seen mph below 110. My conclusion: It's obvious.

Willie

 

But why on earth were you running the same time though roughly? That doesn't make any sense to me at all.

 

Very good question. Hopefully someone more versed in this can explain it because I sure can't!! Something about E/T's indicate torque and mph indicates hp??

One thing's for certain, I've got the proof in the timeslips.

Willie

 

Willie-
Just an observation, but you think the timing lights at the track might be a little off? Looking at your timeslips, your 2 left lane slips are way faster than your 2 right lane slips. But your ETs are nearly the same all the way through.

 

Good observation, but it's just coincidence. I've got a ton of timeslips. Here's two more from the same night:

 

As you said, MPH is an indication of HP, it sure does look like something is KILLING it. the TCC might very well explain it.

I have heard of 700R4's turning on the TCC even though the ECM is not doing it. I think that it has to do with line pressure & leak by in the Valve body but I have not looked into it, to really tell you.

What ECM are you running? IIRC you had a GM ECM with Carrol Super Fueler? could it be that when the converter locks that the knock sensor is picking up a bit of knock & pulling timing out?

BW