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What am I missing??

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Old Sep 20, 2008 | 06:03 PM
  #1  
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06SCGT
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Default What am I missing??

I am running a DSS ProMod stroked 4.6 to 5.0 with the stock 3v heads and Comp Cams Stage 1 Blower Cams SPR. I have a 2.6 I/C KB and I have replaced the BAP with the Shelby fuel pump, and a 3000 stall converter.I had the car on the dyno and it only produced 350 rwhp and I know we should be a min of 500 RWHP. Cam timing is correct and the AF ratio is good. I am at a loss to where we went wrong. With the stock 4.6 components and the KB with 9psi and KB's shoot out tune it was much stronger and ALOT easier to drive! (although it did break a con rod) It feels as if I am driving a 2 stroke....the higher in the rpm I am in the better it runs ( I have checked cam timing 3 times and it is correct). I sent the Blower to KB and they checked it out and say its fine ( shows proper boost on the dyno). I am getting very frustrated and I am in the process of talking to Comp Cams to see if they can shed any light. I have read on this site several posts where you guys with the experience has helped people out. I am an old school racer that has no experience with todays 3v technology. Any help would be greatly appreciated.
Old Sep 20, 2008 | 08:22 PM
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Higher flow injectors maybe?
Old Sep 20, 2008 | 08:43 PM
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60# injectors Fuel Flow appears suffecient
Old Sep 21, 2008 | 12:48 PM
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Were the cams and blower professionally installed? Also what PSI are you running? What is the compression of your engine? Also check out your GT500 setup, make sure it is working properly.
Old Sep 21, 2008 | 03:56 PM
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I did the Blower, and the cams were done by a local Mustang Shop. I was at 9psi and it made around 350 RWHP put on a 12psi pulley and it lost 10 HP! Compression ratio is 8.6:1The Fuel Pressure and everything that has to do with the fuel system is all on the high side of perameters. I am at a total loss and about to go to the stock cams, I had no issues with them!
Old Sep 21, 2008 | 04:46 PM
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Try another dyno, did you do that yet?
Old Sep 21, 2008 | 06:59 PM
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Take her in for a good dyno tune. They should be able to figure out what the problem is. Have the air/fuel and fuel pressure monitored. Also they will be able to see your exact boost levels. That would be your best option before you go in and yank out those cams. However if you still wants those cams out I will be glad to take them off your hands!!
Old Sep 21, 2008 | 08:01 PM
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You didn't say what tune you are currently using. If your still using the kb tune i'm gonna guess thats your problem since you stroked your 4.6, changed cams, and added a stall converter. If you had it dyno tuned then i'd try a different tuner.
Old Sep 22, 2008 | 08:16 AM
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I had it dyno tuned and this guy is very repetable, not sure what the issues are and he doesnt either. Guess I better look at someone else for the tune!! The dyno shows that it is putting out the proper boost and A/F Ratios are in line,timing is within reason for 92 octane, I am thinking he has missed something with the camshafts.I just dont know if its big enough to be 150 HP min. off why he cant see it....maybe it is the tuner....
Old Sep 22, 2008 | 10:26 AM
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Originally Posted by 06SCGT
I had it dyno tuned and this guy is very repetable, not sure what the issues are and he doesnt either. Guess I better look at someone else for the tune!! The dyno shows that it is putting out the proper boost and A/F Ratios are in line,timing is within reason for 92 octane, I am thinking he has missed something with the camshafts.I just dont know if its big enough to be 150 HP min. off why he cant see it....maybe it is the tuner....

Your tuner should be able to figure out the problem. If he cant then yeah I would defiently be looking for another tuner. I would do a little research and see who you can find. Where are you located?



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