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-   -   Built engine question (https://www.ft86club.com/forums/showthread.php?t=94210)

86 driver 09-02-2015 01:53 AM

Built engine question
 
Are forged pistons necessary or can I just use rods? I want to keep the same ratio as stock anyways.

There hasn't been any reported cases of busted pistons to my knowledge. Only busted stock rods.:iono:

FYI my goal is to be around around 450 hp when it is built. Valve springs will be installed as well. What are your opinions on stock vs forged pistons?

EAGLE5 09-02-2015 02:24 AM

Replacing one without replacing the other seems a bit of a waste.

megamarines 09-02-2015 05:25 AM

Better to just make sure everything is on the same page. Despite the main weakness being fixed, it opens up other problems for parts not up to that level.

350matt 09-02-2015 07:01 AM

I think the stock item is pretty good but if you're aiming for 450Bhp then I think you'll have an easier time getting there with a slightly lower ratio and more boost I mean 10.5:1 is still a reasonable level of ratio for a boosted engine

celek 09-02-2015 09:36 AM

With the stock compression you are fighting Knock to make power. Requiring Higher Octane to compensate. Spend a bit more for Pistons at the same time. I can tell you rods and pistons in our block with Valves springs can yield OVER 700 HP.

smudge 09-02-2015 11:04 AM

I still envy you Yanks with your e85 fuel :( wish we had that in the UK

weederr33 09-02-2015 11:56 AM

Quote:

Originally Posted by smudge (Post 2377576)
I still envy you Yanks with your e85 fuel :( wish we had that in the UK

'Murca!

smudge 09-02-2015 12:25 PM

Quote:

Originally Posted by weederr33 (Post 2377622)
'Murca!

Can I have some of that sweet, sweet freedom sent over via bald eagle please?

86 driver 09-03-2015 12:54 AM

Quote:

Originally Posted by celek (Post 2377503)
With the stock compression you are fighting Knock to make power. Requiring Higher Octane to compensate. Spend a bit more for Pistons at the same time. I can tell you rods and pistons in our block with Valves springs can yield OVER 700 HP.

That makes sense. I'm running a flex fuel kit, so it will be on e85 for that kind of power. My tuner was saying that lowered compression wasn't necessary.

I will definitely look into forged pistons now. Thanks for the heads up.

celek 09-03-2015 10:03 AM

Quote:

Originally Posted by 86 driver (Post 2378503)
That makes sense. I'm running a flex fuel kit, so it will be on e85 for that kind of power. My tuner was saying that lowered compression wasn't necessary.

I will definitely look into forged pistons now. Thanks for the heads up.

Does your builder realize its a factory 12.5:1 compression motor?

EAGLE5 09-03-2015 11:11 AM

Lots of big power cars on stock compression levels. A good tuner can handle it.

86 driver 09-10-2015 07:43 PM

Quote:

Originally Posted by celek (Post 2378719)
Does your builder realize its a factory 12.5:1 compression motor?


Yes. I thought the same thing, but he said that's the way he prefers it.

aagun 09-10-2015 11:47 PM

Quote:

Originally Posted by smudge (Post 2377576)
I still envy you Yanks with your e85 fuel :( wish we had that in the UK

UAE TOO PLZ :bonk:

stevo585 09-11-2015 12:16 AM

Quote:

Originally Posted by 86 driver (Post 2386258)
Yes. I thought the same thing, but he said that's the way he prefers it.

Helps keep the lag down. And if your running e85 full time even more reason to keep stock comp. ratio.


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