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What is the intercooler going to do for top speed?

  • same speed

    Votes: 4 22.2%
  • slower speed

    Votes: 0 0.0%
  • 1 mile per hour gain

    Votes: 3 16.7%
  • 2 mile per hour gain

    Votes: 4 22.2%
  • 3 mile per hour gain

    Votes: 2 11.1%
  • 4 or more mile per hour gain

    Votes: 5 27.8%

  • Total voters
    18
1 - 13 of 13 Posts

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Discussion Starter #1
I should have my intercooler put on my boat sometime this next week. What does everybody think it will do to my top end.

Right now the boat normally runs between 82-84, but has gone 87 on a VERY cold day. Small block chevy, 6-71, 18 foot mako with a dominator, pump gas, spins a B-BC impeller 6000-6100 rpm's.

I am certain that my boost is going to drop with the new dense air. Right now it is at 6 psi, and I am not going to change pullies yet, this guess is for how the boat sits now, but with the intercooler.
 

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On the dyno we ran with intercooler off and then a run with it on.

Motor was a 540 6/71 Weiand 8.2 lb boost and a 90hp gain with it on.

Hope this helps your figures on speed;)
 

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Here we go ... For you guys, Barely any difference. Run a 200 Mile Offshore poker Run and yes the chiller will help keep you where it needs to be from the begining.
 

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Discussion Starter #6
I got the intercooler installed today, but it is raining now. Hopefully it will be nice enough tomorrow to run it and see if anything changed.
 

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The big increase in hp will come from increased PSI you can run with the intercooler.



Darrell.
 

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Discussion Starter #9
On my small block, we were running 6 psi of boost, the final compression ratio was around 12.5-12.7. The blower is underdriven -10.2. I am told that we are going to lose 2-3 psi of boost with the intercooler on. I hope the boat runs the same or better with the set up as it is, if so, I am going to be really happy. Then we can change the pullies, and maybe add some timing. It is really windy and cold today:mad: so I will have to wait untill tomorrow to take it out.
 

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You don't actually lose much boost with an intercooler, except from the small amount of restriction. What does happen is that the hot air is cooled and it therefore is smaller and denser (which is what you want). The number on the boost gauge is lower, but power goes up. You can run more timing, more boost, or lower octane for the same power level too. You will need to experiment with timing, jetting, octane and pulley ratio to really see the gains that are possible. Google: Hookes and Boyles gas laws and you will have a better understanding of what is happening with any blower and intercooler. TIMINATOR
 

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Discussion Starter #11
I finally took the boat out tonight to test the intercooler. We ran it hard and the speed was the same, although it seemed to accelerate harder. The RPMs were the same as before. The one thing that did change was the boost RAISED by 1 psi, not sure what the deal is there:(:(. Definatly need to do some tuning, and work with the timing a little.

So...... everybody that guessed same speed were right:)devil
 

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With that intercooler, you should now be able to put more boost to it.



Darrell.
 

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Discussion Starter #13
Im not sure what to do with the plumbing. I had the water coming off the pump, going through the intercooler, then into the block, then out of the block, and out the boat. I turned down the flow of water with a gate valve, to keep the pressure in the intercooler down, but then the engine is running warmer than I would like, and my oil temps soared. I am going to have to replumb this tomorrow.
 
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