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Discussion Starter · #1 ·
Ok guys, so today was dyno day and I had master tuner Johan help out as well.

Here is the history and results from the last dyno tune day held January this year.

476 ft-lbs
490 HP

This on a cold (5 celcius) day on a mustang 4wd dyno.

Today, I went to the same dyno and redid the tune as I am now sporting a 30T pulley all else is the same. The pulley gave me 2 more PSI and I am now running 10 PSI total. The results were 'dissapointing'

494 ft-lbs
486 HP

SO, what went wrong? Here are some of the 'variables' that are different from January

  • Today was HOT as hell.... 30 celcius versus 5 celcius in January
  • I am now using 94 octane versus 91
  • The intake air temp was HOT as hell 180 F at full boost. It would drop almost instantaneously when the run is over
  • The belt may be slipping..... slightly

So the base run seemed to have already lost power as compared to Jan so I am guessing the heat had a play in this.

Other than that, what could be my problem?

I was told based on how the intake air temp raised and lowered so quickly my Vortech aftercooler may be too small and no capable of handling the excessive heat on a hot day; especially when on a dyno and there is no real air flowing thru it. Maybe needing to go for a different air to air intercooler?

Any other ideas? Seems to be a little low on power :(. Could it be that the dyno just reads low?

But still pretty 'happy' overall as the truck runs well.
 

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One question I ask is , did u Dyno on a new revised tune Johan sent for the 30T ? As for heat your numbers now should be SAE corrected according to your last pull conditions IMO .
 

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Discussion Starter · #3 ·
Yes Maximillion. The final results quoted are the revised Johan tune
 

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OK So I would say no worries there , and to be honest I wouldn't just trow in a first file and expect to perform at its best . I know johan well to tell you that he back down quite a bit on this new tune specially knowing you'll be making more boost , so what u need to do is log and email it to him and he will gradually work up on the timing and fuel adjustment as he sees the LOGS ... Another words don't expect much at this time because he started you up from scratch again .. I am actually impressed at those numbers as they are almost the exact from your previous 32T and I'm 100% sure you have 40-50 AWHP left on the table ...
 

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Discussion Starter · #5 ·
Maximillion, the first run we did was really low in power as you stated. By the end of the day, we did see an improvement of 40 more HP as quoted above.

Johan did tell me he saw the high temps on the top end and feels too that perhaps I have gone past the efficiency of the aftercooler.

Guess I will need to run meth OR find another way to cool her down.

Also noticed I got some belt slippage near the top end (PSI would drop). Im ordering a manual belt tensioner and eliminating the factory one which keeps the belt too lose for a blown application.
 

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Make sure your Intercooler pump is working , that could very well be the cause ..
 

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sounds like heat is your biggest issue. 180 degree IAT, thats blazin! Maybe a front mount intercooler could solve this? I cant see that powercooler being very efficient sitting inside a hot engine bay.
 

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sounds like heat is your biggest issue. 180 degree IAT, thats blazin! Maybe a front mount intercooler could solve this? I cant see that powercooler being very efficient sitting inside a hot engine bay.
Nope wrong , the power cooler is very efficient .. he's issue could be the Intercooler pump or very well be low on coolant etc .. I've seeing Jakes logs with front air to air mount and he's IAT are 10-15* higher then my logs at all times on a much cooler air actually , and let's not mention the loss on boost .
 

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thats really surprising being that its under hood the with all that heat. But you guys with the vortechs know more bout them than i do! lol. didnt think about low coolant...
 

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Dump the aftercooler completely and spray methanol.
 

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Make sure your not getting any more belt slip. Definitely get a tensioner.

IMO it would be a good idea to look into a meth kit. Or go back to that dyno on a colder day. Just like Paulo said. Definitely get some datalogs for Johan as he most likely started from scratch.
 
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