Im looking for a -30 dish for a 355 on a 5.7" rod 3.48 stroke and everything looks custom..... Im trying like hell to get to 8.5CR with stock heads and its not looking like I can get there off the shelf. Ive looked at Ross, Diamond, JE, SRP and the best was SRP at -24 but Im not sure about there durability. Ive got a great deal on 5.7 rods and want to make them work!! anyone have any other options?

 

Did you call Diamond direct ? thats what I had to do, They have 30cc dish for my 383 with 6.0 rod and 58cc head It put me at about 8.8.. good luck jim

 

I called them at 4:44 EST and there recording said there office is closed and there normal business hours are Xam to 7PM EST!?! needless to say I was confused...... The more I look the more I see that -22 is pretty standard across the board. I have to check Mahle and wiesco but I dout they have want.

There is more options for the 6" rod but Im getting 5.7 Eagle H-beams from someone local for a great deal and I would like to make them work.

I may be able to get away with -22's since Im taking the worse case and plugging in zero for my deck height. I wont know for sure what that is till I pull the engine... I cant do that till I finish mocking up the hot side...

 

-22 is the best you can get off the shelf without going srp...


Depending on your goals though they arn't bad. I am running them and have put 18psi to them a few times now now. Hitting the dyno Friday to really beat on it.

 

Im sure you will post up your results Im expecting to be pretty close to your setup minus the MS and EDIS8....

 

We carry Diamond Pistons, and I am sure we can find something to fit your needs.

 

Unless the block was decked, chances are the piston will be in the hole between .010"-.020". That seems to be the normal range of the LT-1 motor. You can then just deck the block to increase the compression ratio to what you want along with choosing the head gasket thickness you need.

 

^^But he wants to decrease it

 

On a 355ci - 4.030" bore x 3.48" stroke:
58cc cyl. head vol.
22cc piston dome vol.
.049" thick head gasket
.020" Deck height
C/R= 8.7 to 1

Same combination but with a .010" deck height
C/R=8.87 to 1

General consensus is that a C/R of 9.0 to 1 or lower works well for the LT-1 motor when running pump gas and boost.

If that combination doesn't work, sell the 5.7" rod and use a 6.0" rod. Or, order a set of custom pistons as they are usually only a couple hundred dollars more than a "shelf" piston.

 

Yes but I seriously doubt my LE3 heads are 58cc's, Im thining there more in the 54 range and that puts me around 9.5 IF I dont have a zero deck.... And I wasnt planning on going over.039-.040 on the head gasket thickness.... I was planning to use the felpro @ .039

Erick what can you do for me? does Diamond have an off the shelf -26-28-30 that I dont know about? Im going to try to call Diamond direct today and see if they answer there phone....

 

The didn't last time I called, but could make a me a mean set of -30cc ones for @ $1300.

Your heads may not even be 54cc if they have been milled. Check them.

My heads were milled a small amount the first time they were worked on. When I switched to boost my porter had a hard time getting them to 60. Ended up with 59.5. I think I am a tad over 9:1, and so far so good with pump gas and @ 25 degrees of timing.

 

I can get a set of Ross -30's for 797 +85 for the pins......

you have any numbers yet? Im really intersted to find out how you do.

 

APT is at 5pm central

Hope it warms up more - Drove to work with no heat - temps in the teens and windchill about nill.



As far as Ross, they were my choice for customs. Seemed to be the best price. JE didn't want to go that big on a 5.7 piston but said they could.

I found these srps used for I think they were $250... Couldn't pass on it. If I mess one up Ill just start over again.

 

Ya theres a guy selling some used SRP-24's for cheap but I put all the money into the block, crank, rods only to go cheap on the pistons and loose it all becuase I was short sighted now would really **** me off later on..... Some people have had luck with them and it just seems like the people that didnt had problems with there tune and ended up getting some detination. I would more than likely be in that same catagory since ill be doing some of the tune myself along with help from a couple local people. So having pistons that can take a few small mistakes on my part is my biggest motivating factor....

 

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