THIS IS A DOUBLE POST.... SORRY... this is the first time I've posted here and I wasnt sure if I should have this under Engine or Computer Tuning etc.... please move it if necessary....

I dynoed my car at HRH again, and I was very disappointed with the outcome on my #'s.........

These are all my numbers over the last 2 years:

Stock with Direct Flow lid:
309 HP/321 TQ

Lid, ASP Pulley, 160 stat, new plug wires:
314.6 HP/332 TQ

Above, plus TTS LT's with cats, MAFT, MAF ends, cutout:
323 HP/332 TQ

Above, plus Thunder Racing 220 cam:
334.9 HP/342.2 TQ

Granted my car is a '98, but those are pretty dam crappy for the $$ put into the car !!!!!! What the hell..... spend 3k and get a whopping 10 ft/lbs of TQ... what a deal !!!!!! I really thought the cam was going to wake the car up since it had LT's already.......

I am getting 3-4 degrees of KR around 4k, which may be the problem. I've had KR before on my AutoTap and never really actively put in a strong effort to find out what was causing it. I assume thats what's holding this car back alot.

This is my plan.......
Run some fuel injection cleaner and change the fuel filter and see if I get lucky..... highly doubt it, but its simple thing that should be done anyway.
Get some higher octane fuel and see if the KR is real or false knock..........
If its false..... remove the ASP pulley and check it again......
If its real.... then what ??????????

Any other ideas about what is holding my car back so much ????

More info...... my car is an M6. I put in new springs, ( 918's I believe.), pushrods and lifters when the cam was put in. We did run an Air/fuel during the dyno and played with the MAFT to get it to around 13:1 ( 4% rich). Changing the MAFT didnt seem to change the #'s very much.

As far as track times.... I've only been to the track twice (both before the cam install) and I'm not much of a driver. I have a real hard time getting good 60's and spin the tires just about every time. With street tires, the best I've done is 13.41 @104.98with most of my 60's being right around 2.0-2.11 etc..... Like I said.. I cant launch an M6 worth a damn, and especially on street tires. Those times are dam slow for Sacramento CA

Car is a '98 with stock heads and stock intake. The above #'s are with the cutout capped. No codes.

The above numbers are on a DynoJet... the first one was at a different place than all the others. The rest were all done at the same place , on the same machine, same operator, no big difference in weather conditions..

I've considered an LS6 intake and/or LS1Edit, but so far every mod has been worthless for $$ to HP gains. I'm afraid I'm just throwing good $$ at bad. <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

 

What are your timing numbers at WOT? It's possible that due to your significant KR that the PCM is being forced to operate on the low octane timing table. If you have LS1_Edit, copy the high octane timing table values and put the same values into the low octane tables and try again. You'll notice an immediate difference if you are only getting 15-18° total timing at WOT.

 

We ran the car on a Tech II during the dyno, so I dont have a stored record of the runs. When we did the playback, I was getting around 18 degrees if I remember correctly, when the KR hit the 4 degree mark......

I hate to buy LS1Edit just for that, but I may have too......

 

I agree those are kinda low #'s. If your A/F ratio is fine and no knock retard then your car is probably just one of the slower ones <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by DRJDVM's98SS:
<strong>We ran the car on a Tech II during the dyno, so I dont have a stored record of the runs. When we did the playback, I was getting around 18 degrees if I remember correctly, when the KR hit the 4 degree mark......

I hate to buy LS1Edit just for that, but I may have too......</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">you must have a bad knock sensor if you saw 18 on timing with 4 kr

 

Hmm, my car is also a 98 and I dyno'd in april at 324hp 333tq with a lid, MAC headers with rop, catback, and 4.10 gears. I dyno'd again in august after adding a comp 224 cam and mild ported heads and pulled 392hp and 366tq on stock tuning. I'd say your pre-cam numbers are right on, after cam, something is wrong. If you can find out what is causing your possible false knock, Nineball makes a "box" that eliminates falso knock. I think he calls it the knockout box but i'm not sure.

Try swapping the MAF back to a non ported one and see what that does for you. I think the knockout box will do the trick for you. You might have possibly damaged one of the knock sensors when you did the cam swap.

GregM

 

Your #'s are off by about 30hp.Take off the pulley and put the stock one on.That is probly the knock culprit.

 

how could the pully be the culprit

 

I agree with what's been said. The pulley "may" have a little wobble in it triggering the knock sensors. I would also switch some things around to find the true culprit of your knock retard.

'98's have, historically, dynoed lower than the LS6 intake equipped F-bodys. I feel pretty good about my weak dyno numbers for the minimal exhaust and intake mods I've done.

Keep us informed of your findings.