henry172

iTrader: (2)

I ordered a set of these pistons for my 355 lt1 build http://www.summitracing.com/parts/TRW-8KL2256F30/, but the guy that is balancing my motor says they are too darn heavy so I am going to exchange them and pay a little extra for these http://www.summitracing.com/parts/SLP-L2490F30/; they are supposedly lighter than the stock pistons. I am wondering if they are higher compression or lower than the pistons I originally ordered.

jester1614

iTrader: (13)

those second pistons will be higher compression than the first ones, cause they have a 3.4 cc dish as opposed to a 6.1 cc dish

henry172

iTrader: (2)

O.K that's good I want to keep the compression high. Could someone help me estimate what the compression would be with lt1 le1 heads, stock rods, stock crank and a .026" thick head gasket.

stryker1320

iTrader: (3)

There is a link to a compression calculator on the same page of the pistons that you referred to....

henry172

iTrader: (2)

Thanks, don't know how I missed that one.

henry172

iTrader: (2)

It is coming out to 11.84:1; I think I will be fine on 91 octane, what is the highest compression I could run on 91 octane and drive it daily?

gregrob

iTrader: (8)

SCR isn't what determines octane limits, what ate your cam specs, DCR, cranking compression?

gjohnsonws6

iTrader: (12)

the 2256 will work if you want to save yourself a few bucks.Of course it will need to be re balanced,no mallory metal is needed.only welding up some of the holes on the throws is all it takes.Someone is just being hard headed with you...

speedracer2536

iTrader: (15)

Im curious as to why your engine builder told you they were too heavy.. Im running the speed pro forged 4.030 pistons and they balanced out just fine..

gjohnsonws6

iTrader: (12)

Someone is being lazy and hard headed

gregrob

iTrader: (8)

They are heavy...

speedracer2536

iTrader: (15)

Well ya they are heavy but idk y they wouldnt balance

ThreeHonks

iTrader: (10)

take your stuff to a different machine shop. If he really cant balance a rotating assembly, then you need to go somewhere else

gregrob

iTrader: (8)

Ya "wont balance " is bs. I would choose a different piston though. LT people must think it's a sin to use anything besides SRP or Speed Pro. There's a reason its the cheapest forged stuff you can find.

henry172

iTrader: (2)

Yes he said he could balance it, but it will cost me more to balance and would not run as wall as the others he recommended. He also commented on the friction the first pistons will put on the cylinder.

RamAir95TA

iTrader: (2)

They are a reliable budget piston and 99% of the people on this forum don't need a super lightweight piston, nor would they be even able to tell the difference. Tons of guys are going fast with them, including myself. It's not a sin to use what's less expensive and equally as dependable as pistons twice their cost.

I suppose it's more personal preference, but I chose them in my build for their reliable track record and see great results.

henry172

iTrader: (2)

What speed pro pistons did you use the 2256?

RamAir95TA

iTrader: (2)

I was specifically talking about SRP pistons, not Speed Pros (per gregrob's post).

henry172

iTrader: (2)

SRP'S are just fine; is anyone running the SLP-L2490F30 pistons?

speedracer2536

iTrader: (15)

I dont see anything wrong with the speed pro's either.. I have run them in several other motors and they have never failed.. I plan on hitting my motor now with a 200 shot with the speed pro's