Need help on piston Selection

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Aug 16, 2001 | 05:44 PM

vettetester

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Melting Slicks

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From: I Am The Chosen One

Need help on piston Selection

i plan on boring the 350 .30 over and i am looking at the dart pro1 230cc's with 64cc chambers what brand and kind of piston would you use to get a compression between 10 and 11?

Aug 16, 2001 | 06:03 PM

shaner

6th Gear

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From: Lexington, KY

Re: Need help on piston Selection (vettetester)

TRW !!!!!!!!!!!!!!!!!!!!

Aug 16, 2001 | 06:56 PM

413shark

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From: Minneapolis, MN

Re: Need help on piston Selection (vettetester)

Vettetester....

those are some mighty big heads, are you racing or cruizing?

I'd have to ask what length rod, nitrous or not, any other info would be nice. TRW does make some good pistons at reasonable prices. I was in the market for pistons for the 413, and it came to my attention that I was in WAY over my head. I decided to let a builder take care of it for me. Sure it's the sissy way out, but I know it will be done right. The first think he asked me was "What are you going to be doing with this motor?" I don't know what he'll put in, nor do I care what brand. He said his work will hold together, and I've seen some of his drag motors hold up very well.

I'll give you my dime's worth when you tell us more about your plans and components.

413shark

Aug 16, 2001 | 07:02 PM

vettetester

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From: I Am The Chosen One

Re: Need help on piston Selection (413shark)

The car will be used to scare the crap out of anyone whos on the road with me and will see a few strip runs. Basically I have the heavest lead foot youve ever seen and want this beefy thing to hold up to me. So far im thinking of the dart pro1 heads and the compcams 270rh i dont know anything about rod lenghts yet im still learning i have a weiand 9004 intake and a holley 600 carb and plan on closing it off with hoker headers and dynomax sidepipes i think pistons are the only thing i am missing from my prospective build up. I am trying to get advise from every where I can and in the end i really want to build the engine myself. hope that helps

[Modified by vettetester, 6:03 PM 8/16/2001]

Aug 16, 2001 | 07:34 PM

tsw71

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From: Indiana

Re: Need help on piston Selection (vettetester)

Vettetester, I would assume you're using the dyno2000 airflow files that I sent you to figure power on this engine. From what I have heard, the HP numbers will not be correct when selecting hyd roller lifters in dyno 2000. You will get a more accurate reading by selecting solid lifters instead of rollers. In the real world, those heads will be way too much for the intake, cam and carb you are planning to use. While they will flow well at the top, you will loose a lot of usable torque down low. Those heads really need a lot more cam and a better intake too. The carb will be way too small for high rpms. You would be much better off with the 200cc heads unless you plan on going wild with the rest of the combination.

Aug 16, 2001 | 09:14 PM

vettetester

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From: I Am The Chosen One

Re: Need help on piston Selection (tsw71)

the 200cc's and the 230cc's cost the same so i figured i could reuse them if i decide to redo the engine at a a later date.
is it not a good idea to put them on?

Aug 16, 2001 | 09:53 PM

tsw71

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From: Indiana

Re: Need help on piston Selection (vettetester)

Quote:

the 200cc's and the 230cc's cost the same so i figured i could reuse them if i decide to redo the engine at a a later date.
is it not a good idea to put them on?

That is exactly what I was thinking when I was looking for heads. I saw that the sportsman and S/R torquers were almost the same price. Unfortunately, they may not yield the same results. I finally decided on the smaller S/R torquers. With the larger runner heads, you will loose port velocity. This will make it a real dog at low RPMs unless you have the rear gears to get you into your upper powerband quickly. If you want something that will run well around town, then too much is not better. If on the other hand, you are serious about making a lot of power now or in the near future, then I say go for the large runner heads, but build a combination that will take advantage of these heads. Go with a circle track cam (solid) that is up into the mid to upper .5" of lift with a slightly mild duration. This is what I did with my tunnel ram motor in my streetrod, The result is a motor that idles fairly well, has decent torque by 3000, will pull to 7800 and makes close to 500 Hp.The 230cc heads will work great with something like this. You will need more carb though and at least 10:1 compression. This has been a very streetable combination and should be good for 12's in the quarter with proper gearing.

Aug 16, 2001 | 10:16 PM

tsw71

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From: Indiana

Re: Need help on piston Selection (tsw71)

Oops. I got side tracked with the head debate. On my next shortblock project, I plan to use the SpeedPro(trw) forged L2417 pistons. These will get you just under 10:1. If you use a thin shim type head gasket, you should get it up over the 10:1 mark with the 64cc heads. These have a single relief for valves that are supposed to be better for flame travel as opposed to the 4 valve relief flat top. I'm not sure what else is available, but check Summit and browse through the different pistons that speed pro offers. There are probably some that are a little less common that would get you close to 10:5:1 or 11:1. The ones listed in the catologs don't give you much to choose from when it come to compression.