Ok well when i get my heads ill want to get my pistons too... i want to get my compression up to 10.5:1 or higher.

what would be the best ones to get? type, brand... forged or not.....


thx

 

First of all, is this a street car? If it is, you may want to rethink 10.5:1 and higher compression. I have just over 11:1 in my .060" over 400 and I cannot hold my car at WOT on 94 Chevron. I need to run 100 octane low-lead aviation fuel for my car to run right.

Next is, what cylinder heads are you using? What combustion chamber size? We need more details before we can give you accurate advice.

 

Well first you should stick to flat top pistons, domed pistons can disrupt fire. So when you buy your heads, get ones with chambers that will get your compression where you want it to be without having to use large domed pistons.

Best ones to get really depend on what you wanna do with the car running nitrous etc. Forged is always nice to have as insurance, but they arent necessary for all set-ups. Its really hard to offer accurate advice without, knowing what you want to do with the set-up.

 

ok well i don't have the heads yet... but ill be eather running Performer RPM heads, or 23* Fastburn.... as there are a new pair cheap local.

i do plan on puttin a weeeee bit of No2 in there... but it will mostly be for looks then anything else.... yes its a streetcar, but a weekend warrior... dirt im from vancouver too... so u know the S/L mission racing on fridays... u know.. ok..

umm so 10.5 is to high? i was always told its a good spot to be at...

 

For a weekend only car I think 10.5 is do able on the street, but only with aluminum heads. I dont think you could pull it off with cast heads. Aluminum allows you to run slightly higher compression on lower octance. I think 10.5 with aluminum heads would run well enough on premium pump gas. But it would still run better with gas like Dirt is using or at least octane booster. Like I said if its only a weekend warrior that wouldnt be to bad.

If your planning on using nitrous at all, you should go ahead and spend the extra $ for forged pistons. JE, Ross, Weisco, are all awesome. Speed Pro also offers very good forged pistons at a little better prices.

 

what type of pistons would be best? cuz i see differ designs on the top of them but i do now know what they do and crap

 

Basically

There are dished pistons, flat tops, and domes.

Dished, means it has a dish in the piston, these lower compression, and are mostly used for forced induction. I think they can be useful for a few other set-ups.

Flat Tops, are basically flat with two or four valve reliefs in them. The reliefs look like small semi cirles. These are what you should use IMO. They are simple, and effective. Ususlay the reliefs make the piston about a -4cc dish

Domed pistons, raise compression of a motor, the bigger the dome the more it raises compression. From my readings though high domes can disrupt fire in teh chamber, so I would recoment sticking to flat tops, and just getting the heads meachined to get the compression ratio you want.

 

ok cool, wants happens when u get heads machining, get bigger valves??? what would that do??? lol im learnin im learnin

 

Yea if you have 1.94 valves you can get upgraded to 2.02 valves, but only do it if you get pocket porting and al done too. Otherwise it wont be that great. What I ment thought, was getting the heads shaved. They take material off the machined protion of hte head and it makes your combution chambers smaller. Like I think those heads you talked about getting have 64 cc chambers, and to get 10:1 you probbaly need to take them down to 58-60 ccs depepding ont eh cubes you end up with and the pistons you use.

 

ok cool, thx.. ill look into that.

 

Now if your budget minded as my car is..... KB hypers will take a decent amount of juice. I have run as much as a 150 plate on my KB's(at 7000 rpm) and it has made a TON of passes on a 125 plate.

KB and Probe Industries also make a decent forged piston.

Im running right at 10.5 to 1 comp with TFS aluminum heads and it runs excellent on 92-93 octane.