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Old 02-14-2014, 04:58 PM   #21
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Ugh, I am doing my best to avoid the new turbo path...
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Old 02-14-2014, 05:00 PM   #22
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The only way i'd even bother trying to hit 300whp reliably on stock pistons, especially at your compression numbers, would be with E85.

If i want to do it on pump, it's going to be Supertechs.


And this is coming from someone who likes to tune his car by turning it up until it explodes, then backing off a click.
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Old 02-14-2014, 05:05 PM   #23
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So consensus is to skip any head work, go with the ST pistons and tune away.
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Old 02-14-2014, 05:07 PM   #24
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Quote:
Originally Posted by Doppelgänger View Post
So consensus is to skip any head work, go with the ST pistons and tune away.

That's what i'd do. It's cheaper, easier, and simpler.

I'd also put more effort into figuring out what's killing your motors. Your car is quick, but i don't think it's making the power where **** should start to go sour. Built motor isn't going to save you from outside errors forever.
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Old 02-14-2014, 05:17 PM   #25
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refresh the head (valve stems, cut valves/seats, resurface) and call it good

then beef up the block. I know people daily driving on forged pistons for 60+k miles so don't think that you will absolutely have to rebuild in 25k, though that is possible. It really depends. Pump gas and pistons I'd either drop compression and hope for the best or go forged.

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I'd also put more effort into figuring out what's killing your motors. Your car is quick, but i don't think it's making the power where **** should start to go sour. Built motor isn't going to save you from outside errors forever.
250 on pump gas on a 10:1 motor with hard track use as well as every day daily driving would absolutely wear/tear the block down within 60-70k miles. sounds about right to me. he also has a turbo that comes on real soon
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Old 02-14-2014, 05:33 PM   #26
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When you mention "refresh", I'm guessing you mean to re-use all the stock parts (obviously replacing valve seals w/new).

Oh, another detail- I'm definitely getting ARP head studs, but what level of importance should I put on obtaining the main stud kit?
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Old 02-14-2014, 05:36 PM   #27
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Quote:
Originally Posted by 18psi View Post
refresh the head (valve stems, cut valves/seats, resurface) and call it good

then beef up the block. I know people daily driving on forged pistons for 60+k miles so don't think that you will absolutely have to rebuild in 25k, though that is possible. It really depends. Pump gas and pistons I'd either drop compression and hope for the best or go forged.



250 on pump gas on a 10:1 motor with hard track use as well as every day daily driving would absolutely wear/tear the block down within 60-70k miles. sounds about right to me. he also has a turbo that comes on real soon


Weird, ok, learn something every day. I figured it was just a question of bending rods vs. not bending rods.

Why would it wear down the block at that compression? Detonation?
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Old 02-14-2014, 05:42 PM   #28
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When it comes to sheer torque, sure, but when det happens it amplifies the force quite a bit. Now do that over 60k miles and I'm sure his engine took quite a beating.

I wouldn't be surprised to see bent rods when he pulls the stockers too.

I'm not sure about mains. I did install arp head studs on my engine too though
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Old 02-14-2014, 05:43 PM   #29
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I would say that detonation is what killed his motor, he went from nice 93 octane in Georgia to the crappy winter 92 blend that we have in oregon that is largely inconsistent with its ethanol content with no difference in tune, Im not super familiar with the hydra ecu in Mike's car but I question the sophistication of the knock detection capabilities that it has. This coupled with the high compression OEM pistons he had I think led to some serious detonation, I know that the quality of our gas fluctuates wildly from summer to winter with winter gas often being the crappiest so Ive always made it a point to get tuned during the winter months. I think with a proper rebuild and a good conservative tune Mike will have a motor that will last significantly longer.
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Old 02-14-2014, 05:58 PM   #30
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I just did a quick run-down of parts and pricing...I'm up to $1830 if I skip the OS valves and go forged pistons...and don't get them coated.

I'm also throwing in a few other parts..clutch, flywheel friction surface, "single" clutch line...
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Old 02-14-2014, 06:24 PM   #31
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Quote:
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Ugh, I am doing my best to avoid the new turbo path...
Oh I'm not suggesting that, I'm just saying it's easier and quite a bit higher on the hp/$ scale vs OS valves. You could spend $500 on 1+ valves and machine work for 20whp, or spend $500 on a GT2876 (and selling your 2560) for 100whp. If you're trying to squeeze every bit out of what you have for class restrictions or something it makes sense, but since adding moar boostz has the same effect for free why not do that first?
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Old 02-17-2014, 05:03 PM   #32
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Ok, so I'm about to pull the trigger on parts, think I'm too worried about cylinder wear/piston slap to feel comfortable with forged pistons....will be going with 4W stock oversize pistons.
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Old 02-17-2014, 05:15 PM   #33
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buy my already completed long block
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Old 02-17-2014, 05:25 PM   #34
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Quote:
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buy my already completed long block
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Old 02-17-2014, 06:44 PM   #35
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Can't tell if serious or not...
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Old 02-18-2014, 01:45 AM   #36
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What was Emilio saying the other day about certain forged pistons are made out of a different material and don't have near the thermal expansion of other brands.
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Old 02-18-2014, 01:46 AM   #37
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4032 vs 2618
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Old 02-18-2014, 01:53 AM   #38
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Isn't one more like OEM in regards to wear and expansion? Which one is it?

Edit: thanks google, Mike go with a 4032 forged piston, especially since you seem to get crap gas in the winter.
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Old 02-18-2014, 01:55 AM   #39
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4032

actually supertech uses 4032
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Old 02-18-2014, 02:08 AM   #40
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Why not just bore it out to 84.5 or 85? Isn't it the same price? Blocks are cheap, I'd want all the cc I could get in a 4032 Supertech
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