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I Feel I'm Making Low Power... Boss 302 Cobra... Should I Be Worried?

Discussion in 'Engine/Tuning' started by Rossim22, Jun 30, 2012.

  1. Rossim22

    Rossim22 New Member Established Member

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    I was getting some work done to the car and had my 03 cobra tuned at the same place. Originally with a returnless system on my posi ported eaton at 17lbs I made 525/543. I was having an issue switching gears on wot runs where the car would hesitate, so I went with a return set-up. Same shop did the tuning and I dropped to 505/520. After ruining a piston, the current shop accused the previous engine builder. Stuck between a cobra and a hard place, they agreed to avoid a bad reputation and cover future labor and tuning, I was responsible for parts.

    I went with the boss 302 upgrade block from modmax and had them build a shortblock with 9.2cr (previously 9.1) able to withstand 1000hp. It was shipped to the current shop who just recently finished installing everything and tuning, this time I'm going with a 93 and E85 tune. I was expecting (hoping) for a 550/570 on 93 and maybe graze 600 on E85. The car put down 502whp and about 520wtq now at 15lbs (same pulley combo) at 11.4afr on 93 but then on E85 made 560/577. Is he just giving me a safe tune for driving around on pump? I'm using SCT

    Thanks
     
  2. Posi

    Posi Had a blast. Established Member

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    Depends on how long the car was cooled down for the 502hp pull. If it was pulling timing and the E-85 tune wasn't then there's 20-30hp easily.

    It does sound like the other tune is safe though. E-85 in my car against straight race gas was 18-20hp on the same day with the car staying strapped down.

    Did you do head work or cams?
     
  3. Posi

    Posi Had a blast. Established Member

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    I'll add if the motor was just broke in and it had hardly any miles on the dyno your hp will go up more and more as the motor gets broken in. When mine had around 100 miles on it, it had been on the dyno 3 times and each time it's made more and more power.
     
  4. Ironhand

    Ironhand Banned

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    The previous shop probably went too far and messed up the first motor and now they backed it down. 11.4 is a touch rich and they probably took some timing out as well to avoid any issues down the road.
     
  5. Posi

    Posi Had a blast. Established Member

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    Find out what the timing is up top in the rpm's for both tunes. Around 6,000 rpm's.
     
  6. Rossim22

    Rossim22 New Member Established Member

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    Just a valve job on the heads and polished the cams.

    This was exactly what he said though I was a little worried that we were doing 500whp runs on a motor just put together but modmax reassured me that it was safe. I did witness a 15hp gain on the e85 with nothing changed.

    I also agree with this. I was planning on taking the car to another shop known for their work with domestics and have them dyno it and look through the sct files and see if anything stands out.
     

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