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Maximum boost for autocross on stock 1.6

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Old Mar 20, 2015 | 11:57 AM
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Default Maximum boost for autocross on stock 1.6

Quick question, just dyno tuned my 1.6L and it put down 243hp @ 11.5-12psi. Do you guys think I should turn the boost down to maybe 10psi for autocross/ daily driving? 8psi yielded ~ 200hp
The engine is stock, freshened up with Mazda parts around 15000 miles ago. I have a stock 5 speed transmission as well. I don't have money to be blowing on rebuilding the engine, I hope it lasts this season, maybe 10-15 autocrosses.

For the record, I am running a sr20 t25 turbo, water to air cooler.

Thanks!
Old Mar 20, 2015 | 01:28 PM
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Depending on torque, you are pushing the limits of the stock rods. I would turn it down based on that alone.
Old Mar 20, 2015 | 01:41 PM
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Originally Posted by guttedmiata
Depending on torque, you are pushing the limits of the stock rods. I would turn it down based on that alone.
shut your mouth, there is only 1 correct answer to this question. He should run ALL OF IT!!!!!
Old Mar 20, 2015 | 01:49 PM
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I'd turn it down for DD purpose/stock rods, crank it back up for autox where it counts
Old Mar 20, 2015 | 02:06 PM
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Right, because rods bend in every other situation but not an autocross. Idiots
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Old Mar 20, 2015 | 02:09 PM
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His torque number is nowhere near the danger zone.

I'd run where it sits.
Old Mar 20, 2015 | 02:19 PM
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Would you mind posting your dyno graph with the T25? I would love to see how well your 1.6 spools that turbo.
Old Mar 20, 2015 | 02:25 PM
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Originally Posted by 90civichhb
Would you mind posting your dyno graph with the T25? I would love to see how well your 1.6 spools that turbo.
I posted it under the dyno section
Old Mar 20, 2015 | 02:28 PM
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I am subbed to your build thread, but didn't see you post it. Just assumed you were wanting to keep it private or something.
Old Mar 20, 2015 | 02:30 PM
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Your max torque wouldn't have gone above 225ftlbs on that graph, on a dyno that isn't likely to be a heartbreaker.
Old Mar 20, 2015 | 02:45 PM
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ALL OF IT
Old Mar 20, 2015 | 02:55 PM
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Originally Posted by btabor
.... I don't have money to be blowing on rebuilding the engine, I hope it lasts this season, ...
180kpa should be fine as long as you're not knocking. If you want to ease your mind, set it to 170kpa and just enjoy it.
Old Mar 20, 2015 | 06:17 PM
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All of it for autocross. So little time spent at peak torque with RPM's rising so quickly in second gear it becomes hard to hurt anything other than transmissions if you have any kind of decent tune.
Old Mar 20, 2015 | 06:21 PM
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Originally Posted by shuiend
shut your mouth, there is only 1 correct answer to this question. He should run ALL OF IT!!!!!
came in here to post this
Old Mar 20, 2015 | 07:35 PM
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Originally Posted by 90civichhb
I am subbed to your build thread, but didn't see you post it. Just assumed you were wanting to keep it private or something.
Nope not trying to keep it private. I have to post it there as well. I like to show off my water to air cooler and how effective it is. Credit to Harold Hammerly for building it.
Old Mar 20, 2015 | 07:37 PM
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I think I'm going to turn it down to 10psi just so it lasts this summer. Maybe throw rods, oil cooler, be pump and a 6 speed next winter and crank it up to 14 psi
Old Mar 20, 2015 | 07:40 PM
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Old Mar 20, 2015 | 09:59 PM
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Easy to be cavalier with someone else's car and money.

Run ALL OF IT if you can get any of those giving said advise to sign a contract stating they will fund the rebuild if it fails.

Now where is that chirping cricket smilie......
Old Mar 20, 2015 | 10:10 PM
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I think my plan is to run ALL OF THE AUTOCROSSES instead of all the boost. I think 10psi will do. I was trying to get advice from someone with the same/ similar setup
Old Mar 20, 2015 | 10:55 PM
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Make less than 240ftlb at the crank calculated from the dyno sheet.

This is literally the only correct answer.

Dann
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