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Old 02-02-2017, 11:26 PM   #1
WhatTurboLag?
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Default Refresh H TUFF rods eith 625 hardware for 600-700whp?

So. I will keep it simple.

I have a 75 lb/min turbo and am going one of two ways with my motor build. Low cost and limiting power. Or high cost and shooting for whatever the turbo (and rods) will allow. I bought the Manley Htuffs with like 3k on them. They have the standard ARP2000 hardware.

Would the 625 rod bolts help these rods up near 700whp? It's a small turbine/turbine housing/spool valve so it'll be decently torquey. Is it even worth refreshing the rod bolts in general?

Then that being said. What's the best way to find the upgraded rod bolts? I assume just call Manley/ARP.
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Old 02-02-2017, 11:58 PM   #2
stu
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The guys at Manley and outfront say the H tuff should handle 250 crank hp per cyl with the 2000s
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Old 02-03-2017, 01:05 AM   #3
jamal
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Well, my understanding is that the forces on the rod bolts mostly come from RPM and piston and rod weight, not so much the power. And then the rod itself is stressed more by peak cylinder pressure.

So if redline isn't going to be particularly high, I don't think the ca625 bolts are necessary. The real way to tell if you need new bolts or not is to measure them before and after. If they've stretched, they need to be replaced.
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Old 02-03-2017, 02:32 PM   #4
station2station
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When you are looking into 625's, case bolts, and 1/2" bolts pay attention to your mains. You are getting into some machine work and potentially very specific bearings.
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Old 02-04-2017, 01:59 AM   #5
user1029
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Should be fine
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Old 02-04-2017, 05:59 PM   #6
KillerBMotorsport
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Quote:
Originally Posted by jamal View Post
Well, my understanding is that the forces on the rod bolts mostly come from RPM and piston and rod weight, not so much the power. And then the rod itself is stressed more by peak cylinder pressure.

So if redline isn't going to be particularly high, I don't think the ca625 bolts are necessary. The real way to tell if you need new bolts or not is to measure them before and after. If they've stretched, they need to be replaced.
^ this right here.

625s will be more tolerant of a miss-shift as well.
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Old 02-04-2017, 08:00 PM   #7
WhatTurboLag?
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I will be running a beefier piston than necessary, turbo tuffs.

Stock redline as I'm on stock heads at this point in time.
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