My shortblock is nearing the finishing touches and I need to get the pistons over to the machinist. Given that some go with the Ferrari of pistons(Diamond?) while others go with Kia of pistons(TRW) I want something in the middle of the extremes. I'm going with 14 to 17 psi on my T76 w/MPS Wheel on a 4340 forged crank 355 LT1, using Realquicks Log Manifold for the hotside. The car is going to be a daily driven/weekend track application. The static compression ratio is going to be 8.5, the block zero decked, the heads ported LT1 castings (I/E flows of 275/195), 60# Mototrons, PCMforless turbo tune, TurboSmart 38mm WasteGate, TurboSmart Megasonic Blow off valve, OBX Intercooler. You guys with 'real world' experience in piston selection, could you recommend a piston/ring (and possibly a vendor) that would satisfy the needs of such a motor/application? I'm ready to buy right now. I'm ordering the 5.7" H Beam rods (Rated to 1,000Hp) right now as well.
Thanks!
Dave

 

JE is my piston of choice. Assuming you are building a low CR motor you should consider the "Extreme Duty 23º Inverted Dome". Hellfire rings are what I recommend and use.

Rich

 

Thanks for the response. I'll look for them. I think when I was fielding some questions regarding inverted dome size, they said it would take around -31 CC's to get 8.5:1 SCR with the ported LT1 castings, zero deck, .03x compressed head gasket. Do you have a vendor you can suggest?

 

If your machinst can get them at a decent price, that is going to be the most convenient. It will make him happy to make a couple of bucks on the deal. I don't buy many parts retail, but all the big retailers sell JE. When I buy retail I use Flatlander Racing at http://www.flatlanderracing.com/ or Summit. My buddy Bob Kennedy also sells retail, but I don't want to seem to be doing free advertising.

Rich

 

I've learned to stay away from SRP on boost. Ross in my current motor are holding up well.

Mike

 

I guess you'd assumed (correctly) that I'd scanned the field and found JEG's SRP Super/Turbo pistons (-21cc or -24cc?) for $5x each.
Are your Ross pistons a shelf item or custom? I've put in a 'cam request' to Cam Motions for a custom turbo Cam this past Friday.

 

another for je a friend of mine has em in his 97 s-10 with a pro charged 502 in it and they hold up real well he scattered a set of wiseco on the same set up i think his are a -24 dish and 8.8-1 on 13-18 lbs of boost

 

Custom. Got them from gofaststuff.com for I think about $600 for the set.

Grr.

 

Nice on the pistons. Did they provide the rings and a recommended ring gap for your setup as well?

Grr? on the cam request? What's up?

 

The rings did come with them. As far as I know, all ring manufacturers recommend a generic end-gap. However, we learned some interesting stuff from the guys at JE a couple years ago and I've been going much wider ever since. I think my current motor is .028-.030 on the top and .018-.020 on the 2nd.

About the cam request. . . I'm not a big fan of Cam Motion. When they call back with the cam spec's, quiz them on why they chose those numbers. They never ask for backpressure, though that should be a key element in choosing a turbo cam. All of their recommendations are reverse split with about 5 deg more on the intake, and all ground on a 114. That CAN'T possibly be right for all the combo's they recommend cams for. . .

Mike

 

Mike, Here's their quote...
===============================================
Dear David,

Recently, you submitted an Cam Request named Turbo 355 LT1 using our online Cam Request system at cammotion.com. The request was for a HROL for a Other. We have reviewed your submission and have provided the information below. Thanks very much.

--------------------------------------------------------------------------------

RECOMMENDATION
Grind Number 1533/1533/14+4
Duration (intake/exaust) 228/228
Lift (intake/exaust) 563/563
Lobe Center Separation 114
Intake Centerline 110
Comments 355.00 with Cast Gear Core 300.00 for billet core
Price US$


Please advise if you wish to order
We can ship in as little as three days!


Cam Motion, Inc.
2092 Dallas Drive
Baton Rouge, LA 70806

=================================================

 

Sounds pretty generic, though a tad different from their typcial recommendation.

BTW, a few years back, I switched to a 226/226-114. Results were underwhelming, so I put my 224/236-114 cam back in.

Mike

 

Well. I called around and checked various sites. The SRP -31 piston was a good deal at $500ish for the set was very attractive but I've found about 3 guys that said they don't trust them after either suffering a failure themselves or knowing a bud that had in a supercharged/turbo motor. I know this *could* be related to setup, ringgap, detonation, fuel system issues, overly aggressive timing, etc but the issue is out there to evaluate. I have NOT found people claiming the Diamond Pistons are shattering. Maybe I didn't look in the right places but it seems to carry high regard. I checked on the Ross pistons but they were well over $700 and I don't think that was with wrist pins. I settled on the 5.7" -31 Diamonds with Total Seal AP series rings. This, after conferring with Eric at Victory. They were $770.99 for Pistons/rings and shipping/handling. Thanks for the input everyone!

 

I had the 224/236 Extreme w/1.6 roller rockers
(224/236 .537/.556 112 Xtreme) using the Crane 10308-1 spring kit in my prior 355. On pure motor, driving off the highway, switching to ET streets in a full 3,650lb TH350 2800 vigilante equipped street car, I went 12.0 at 116 mph. Added a 100 shot from an NX kit for the next pass, 11.1 @ 121. Add to that, the cam sounds wicked at idle....

http://www.taekwondoplus.org/z28/224Idle.mpg

Hmmmm.... I may go back to that cam. Did you have to special order that LSA? I bought my 224/236 3rd hand (Denny McClain, Mike Graham used it before I bought it from Mike) and it may be special ordered with the 112 LSA for all I know.

 

I would. Consider a 1.7 intake rocker, though, to get some lift out of it. I'm using high lift lobes for .605 intake with a 1.6.

Yea, it was a custom grind from Comp.

Mike