my air/fuel was smooth high 11s. torque falls off @ 3700 and hp drops with small spikes @ 5700. belt shredded, car was hot after 7 pulls. can anyone think of more excuse, i need them with my mods!
425 hp @ 5700 rpms 478 tq @ 3500????
- Thread starter topless10th
- Start date
he said he left the stock timing curve in plus 1%. a/f was solid high 11s after tip-in. p.s. weldcraft wheels widened a stock pair for me for 380.00 shipped is this the weakest cobra ever? why? is the 2.93 and 4lb lower combo spinning the eaton too fast? should i try a 3.10? help!
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Is your s/c ported ? If not you might be creating a little to much heat .
Do you plan on getting any track numbers soon ? If so just hold out for the track numbers and put the dyno numbers on the back burner .
Do you plan on getting any track numbers soon ? If so just hold out for the track numbers and put the dyno numbers on the back burner .
no, my charger is factory stock. i suspect this may be part/all the problem.
Do you have an aftermarket HE? You may be making just too much heat for the stock system to handle.
I had major belt issues when I put my lower on and was shredding belts. I had to do some major shimming on the lower, tensioner, and upper pulley to get it all aligned. What size belt did they use? Can you post the dyno graph?
My combo is 2.8/4lb lower, 100mm aux idler, 3-100mm idlers, 1-90mm idler, 3.2" alternator pulley, lower idler in bottom hole, and the belt is a gatorback 4080780.
My combo is 2.8/4lb lower, 100mm aux idler, 3-100mm idlers, 1-90mm idler, 3.2" alternator pulley, lower idler in bottom hole, and the belt is a gatorback 4080780.
i have both the afco heat exchanger and precision fabrication reservoir. belt was a 80 1/4 inch gates micro-v. alignment was my first thought, how did you check yours. my belt seems to stay true and pulleys look aligned. i have billetflow 2.93, new idler bracket, 3 100mm idlers, 1 92mm idler, larger metco alternator pulley, 4lb metco lower. not sure which hole lower idler is in. could have used a shorter belt, couldnt find anything between 79.5 and 80.25" and im pegging my meter too, how is that possible?
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Had to do to a 81" Gator belt!
I mover lower idler to top location and this was the smallest belt I could get on even with the Idler pulley removed then replacing it last! Hoping to stop belt slip too. To me you need a ported Eaton to run 2.8/4 lb lower. BAP and MAFX are needed too. IMHO :coolman:badcobra said:
belt was 80 1/4". i go to another dyno today to check the results of mondays pulls. i just cant imagine that my car is that much weaker than everyone elses. i dont expect the be 500hp, but i was looking for 450-475. doesnt that sound right? i ordered a 79 1/2" belt from napa and a 92mm idler from billetflow to swap out with one of the 100mm ones so that the 79 1/2 will fit. it will still be tight.
just as i suspected... paul's automotive engineering in cincinatti ohio screwed me. my dyno guy says their wide-band must be bad, the first identical pull with no changes but weather being hotter resulted in similar horsepower and torque but air/fuel was off the chart rich everywhere. PAE used a wide-band sensor in my tailpipe. new dyno guy used the one that connects to o2 sensor and an in-car wide-band (they matched). when PAE installed my "custom" tune in the predator they removed the diablosport pulleytune which left my new dyno guy limitations in his ability to correct the air/fuel. he slowly made his way to a 15% decrease in fuel across the board (maximum allowed by predator on custom tune) which resulted in an average of 25 more hp and 40 more lb of tq with an air/fuel that was still in the low 10s. in this rich condition car made peak numbers of 438 hp and 488 tq, both with nice flat curves. shouldnt PAE give me my money back? i guess i need to send my predator back to diablosport to have this "custom tune" erased. im pissed! yet relieved that the car has some more potential.
Sounds like you have some tuner issues going on. You may need to get the Diablosport MAFia to stop the MAF from pegging.
i definitely have tuner issues. new pulls didnt show a pegging of the MAF. just across the board F'd up a/f. after pulling out 15% of fuel it was still off the chart rich at 4k.
Ok, some things I have observed from this thread. First, PAE sucks. Second, your new tuner isn't much brighter. The custom tune from PAE just needed to be deleted off the Predator and all the ones that come 'stock' with it would have been back. If your tuner is too dumb to figure that out, then he needs to get fired immediately. Also, your new tuner should not be basing his supposed 'custom' tunes off the ones that comes with the Predator. A custom tune is a tune written from scratch specifically for your car.
Here is what I would do. Hire a competent tuner that many people use and have success with on these boards. Go to a dyno operator that actually knows what they are doing and people here have had success with to check the tune. Have the dyno operator screw the wide band in the rear 02 sensor on the driver side which will require the rear 02's turned off on in your tune. Get the MaFia and BAP that you surely need for your combo as well. If you do what many others have done successfully, you will get the similar results. Good luck.
Here is what I would do. Hire a competent tuner that many people use and have success with on these boards. Go to a dyno operator that actually knows what they are doing and people here have had success with to check the tune. Have the dyno operator screw the wide band in the rear 02 sensor on the driver side which will require the rear 02's turned off on in your tune. Get the MaFia and BAP that you surely need for your combo as well. If you do what many others have done successfully, you will get the similar results. Good luck.
sounds like solid advice, thanks alot.
badcobra said:
Not so simple badcobra. Why in the hell would the tuner want to delete a program the customer paid PAE for without checking with them first? Wouldn't leave much of a leg to stand on when trying to get compensated for his poor dyno tune session, now would it?
But let's say that he did delete the custom tune. He would have been left with a "Pulley Tune" and "Stock Tune" only. His "Tuner" doesn't have the software necessary to flash his Predator. Meaning that Topless10th would have been sent on his way with a 2.93 Upper / 4lb lower, countless other mods, and a tune that would be sure to blow his engine should he happen to forget and go WOT.
Lastly, he basically took the car to the second dyno to verify that that the PAE Tune was correct (since the number were obviously lower than expected). As it turned out, the tune was way off. And you need to first realize that he didn't take it there for a custom tune. The "tuner" was just trying to make the tune better than it was when it arrived. Which he did.
So before you go planting the seed in someone's mind that their tuner is "dumb", you might want to get ALL of the facts first. His tuner may be a lot of things, but "dumb" isn't one of them. IMHO.
Rob Raymer said:
Rob, we can agree to disagree on this. Topless has wasted time and money at two places who don't know what they are doing. He needs to hire a competent tuner that writes true custom tunes, and go to a dyno operator who will screw the wideband in the rear 02 driver side bung and check the tune that a competent tuner writes for his predator. Or simply skip the dyno and buy a dynojet WBC and be done with it.
Topless, buy the AC adapter and serial cable for your Predator so you can download the custom tune from it and save it, and also upload a new custom tune when the tuner sends it to you. If you have the $400 dollars, buy a wideband commander so you can datalog and record the info for your tuner and get the tune dead nuts on. Then go back to the dyno to see how much power it puts out. This will save all the time and hassle of going back and forth to the dyno. It will pay for itself in no time flat. Good luck.
badcobra said:
Once again, it's not that the second place didn't "know what they were doing". They did what they were paid to do. Verify that the PAE tune was a good tune (which it wasn't). I don't see how that was a waste of money. Nor do I see how that would get the guy labeled as "dumb". I know for a fact that he writes and dyno tunes FAST, Accel DFI, AEM, LS1/LT1Edit, and the new BigStuff3 system. Not having the Diablo equipment doesn't make him dumb....just unequipped.
Know what I mean?
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