CRG Discussion Forum
Welcome, Guest. Please login or register.
Did you miss your activation email?
July 31, 2014, 12:37:14 PM

Login with username, password and session length
Search:     Advanced search
Welcome to the CRG Discussion Forum!
Forum registration problems: Make sure you enter your email correctly and you check your spam box first. *Then* email KurtS2@gmail for help.
102515 Posts in 12093 Topics by 4669 Members
Latest Member: paulmanta
* Home Help Search Login Register
+  CRG Discussion Forum
|-+  Camaro Research Group Discussion
| |-+  Restoration
| | |-+  302 engine build piston recomendations
« previous next »
Pages: 1 [2] 3  All Print
Author Topic: 302 engine build piston recomendations  (Read 5525 times)
zman1969
Member
***
Posts: 107



View Profile Email
« Reply #15 on: September 17, 2012, 07:39:13 AM »

after thinking more about the use this 302 will get I am thinking more about the Ricks pistons - correct dome , tighter fit, less oil consumption - who has used these? what ring thgicknesses? 3/32 or 1/16" ? I really cant find any more specs on them but I did find that Summit Racing carries them
Logged

Rich

69 RS/Z DZ302 Daytona bumble bee
69 T/A clone LS6/6sp
69 Nova SS 396
69Z28-RS
Hero Member
*****
Posts: 2280


owner since '76


View Profile Email
« Reply #16 on: September 17, 2012, 12:47:54 PM »

tighter fit = more friction, lower horsepower, lower RPM... 
Logged

Gary W.  /  69Z28-RS, 72 B 720 cowl console rosewood all tint
69 Corvette convertible, silver/black 350 hp,
60 Corvette white/red, 72 Corvette coupe (2), 
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55 Nomad, '57 Nomad, '57 B/A Sedan
zman1969
Member
***
Posts: 107



View Profile Email
« Reply #17 on: September 17, 2012, 05:09:37 PM »

tighter fit = more friction, lower horsepower, lower RPM... 
this is going to be a driver,   I'd really like to see that comparison on a dyno LOL less clearance than forged yes but there is still clearance - more friction from the rings than the piston
Logged

Rich

69 RS/Z DZ302 Daytona bumble bee
69 T/A clone LS6/6sp
69 Nova SS 396
Stingr69
Member
***
Posts: 395


View Profile Email
« Reply #18 on: September 18, 2012, 10:37:40 AM »

Hypereutectic pistons do not tolerate detonation or high RPM very well. Lots of pictures on the net of top ring grooves blowing out when used hard. You will find plenty of people blaming the installer not opening up the ring gap like they were advised when they bought the Hypereutectics but even with that, there are too many broken high performance hypereutectic pistons out there.  The castings do not behave the same as a forging when subject to hard use.  High heat causes the top ring gap to close up and butt and then the piston blows out at the top ring with a big chunk of aluminum flying aound causing all kinds of damge. That is why you pay more for forgings.  In a "driver" L48 type stock application they make a lot of sense and yes I would use them there but I can't see puting them in a 302 that will be driven like it was intended. Too much RPM's, and potential for detonation.    JMO.

-Mark.
Logged
69Z28-RS
Hero Member
*****
Posts: 2280


owner since '76


View Profile Email
« Reply #19 on: September 18, 2012, 11:43:41 AM »

and WHY have a Z28/302... unless you're going to build it and drive it as it was designed??...
If you want a 'daily driver' with 'Z28 emblems'...then pull the original 302 (store it away for *resale day*), and stick a stock 350 or 307 in it...

...the 302 (as designed) was classified by Chevy as a SHP (special high performance) engine....  not very many got that classification.
without the full gamut of factory parts, it ain't special...  (it's not the DZ stamp on the block that made it special)... Smiley

  Smiley     Just One Man's Opinion..  Smiley
Logged

Gary W.  /  69Z28-RS, 72 B 720 cowl console rosewood all tint
69 Corvette convertible, silver/black 350 hp,
60 Corvette white/red, 72 Corvette coupe (2), 
90 ZR1 red/red #246, 90 ZR1 white/gray #2466
72 El Camino, '55 Nomad, '57 Nomad, '57 B/A Sedan
zman1969
Member
***
Posts: 107



View Profile Email
« Reply #20 on: September 19, 2012, 12:57:57 PM »

and WHY have a Z28/302... unless you're going to build it and drive it as it was designed??...
If you want a 'daily driver' with 'Z28 emblems'...then pull the original 302 (store it away for *resale day*), and stick a stock 350 or 307 in it...

...the 302 (as designed) was classified by Chevy as a SHP (special high performance) engine....  not very many got that classification.
without the full gamut of factory parts, it ain't special...  (it's not the DZ stamp on the block that made it special)... Smiley

  Smiley     Just One Man's Opinion..  Smiley
well your right i should sell it and buy a 307 car
in the past my Z has had a 327 in it, a 396 a 427 and a 350 now I want the real 302 in it. with exhaust manifolds whats so wrong with having this as a driver? no more str$$t racing, no track time so I dont need a $1200 set of JE pistons... yes i will spin it up  and have some fun. after looking at all the options- Speed Pro, SRP, KB, Ricks, Wiseco its amazing that for whatever reason they are all different in compression and dome heights, rings, compositions
Logged

Rich

69 RS/Z DZ302 Daytona bumble bee
69 T/A clone LS6/6sp
69 Nova SS 396
Jerry@CHP
CRG Member
*****
Posts: 1445



View Profile Email
« Reply #21 on: September 20, 2012, 01:40:52 PM »

The J&E's are about $650-700.00.  Not $1200.00, this is what I use in all the engines that we build.......

Jerry

Logged
zman1969
Member
***
Posts: 107



View Profile Email
« Reply #22 on: September 21, 2012, 12:00:01 AM »

The J&E's are about $650-700.00.  Not $1200.00, this is what I use in all the engines that we build.......

Jerry


Jerry, after we spoke that's what they quoted me maybe I should try another vendor?
Logged

Rich

69 RS/Z DZ302 Daytona bumble bee
69 T/A clone LS6/6sp
69 Nova SS 396
Jerry@CHP
CRG Member
*****
Posts: 1445



View Profile Email
« Reply #23 on: September 21, 2012, 09:11:32 PM »

You should.  The J&E's will make more power too.  I've been getting 365-4000hp with a stock rebuild now using the 30-30 cam.  Stock Eliminator ring combination and some other tricks that pick up the power band.  The heads is where the vary so much.  Core shift, etc.  No two head flow the same. 

Jerry
Logged
zman1969
Member
***
Posts: 107



View Profile Email
« Reply #24 on: September 23, 2012, 11:36:10 AM »

JE piston # 123567 and I cannot find any one that prices them online - any suggestions where to try?
Logged

Rich

69 RS/Z DZ302 Daytona bumble bee
69 T/A clone LS6/6sp
69 Nova SS 396
Jerry@CHP
CRG Member
*****
Posts: 1445



View Profile Email
« Reply #25 on: September 24, 2012, 09:44:29 AM »

Yes, call Burtonsville Machine and ask for Bub.

301-490-3131,

Good luck,

Jerry
Logged
zman1969
Member
***
Posts: 107



View Profile Email
« Reply #26 on: September 24, 2012, 11:47:38 AM »

I spoke to Bub he suggested the JE/SRP piston 202890(for .030) he said this is what you use in your rebuilds and the 123567 was a custom built piston we didnt talk $ he suggested Jegs $832 for a set of those SRP are around $563 any issues with the SRPs?
Logged

Rich

69 RS/Z DZ302 Daytona bumble bee
69 T/A clone LS6/6sp
69 Nova SS 396
Jerry@CHP
CRG Member
*****
Posts: 1445



View Profile Email
« Reply #27 on: September 24, 2012, 08:08:31 PM »

You can use them.  We have in the past when cost is an issue with a customer.  Dome configuration is slightly different but very close to the NHRA Stocker pistons. 
Logged
lynnbilodeau
Member
***
Posts: 264


View Profile Email
« Reply #28 on: September 25, 2012, 12:53:58 PM »

Only slightly off topic.

Jerry, are you using the comp cams 12-107-3 camshaft in stock z28 builds?  Do you consider it a dead on match for the original 30 30?

I know JohnZ recommends the Federal Mogul.  Quote:  "Don't know offhand if the Comp cam is a dead-on duplicate or not, but the Federal-Mogul/Speed-Pro/Sealed Power cam is - their #CS-118R (cam only) or #KC-118R (cam and lifters)."


One more questions, as I am getting ready to put together a couple 302's:  what valve springs are you using?  Thanks.

Lynn
Logged
JohnZ
CRG Member
*****
Posts: 4051


View Profile Email
« Reply #29 on: September 26, 2012, 10:51:55 AM »


One more questions, as I am getting ready to put together a couple 302's:  what valve springs are you using?  Thanks.

Lynn

The original springs were GM #3911068, same as used in all other small-blocks. They're still available from GM, but the same spring is available from Federal-Mogul for about 1/3 of the GM price as their #VS-677 (F-M makes them for GM - it's the same spring). "Improved" non-FM aftermarket versions of the "30-30" cam may require different springs - the originals were 90# closed, 190# open.
Logged

'69 Z/28
Fathom Green
CRG
Pages: 1 [2] 3  All Print 
« previous next »
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!
Page created in 0.083 seconds with 18 queries.