are speedpro hyper pistons any good?

[TurboMonte 2]

Many engine rebuilders now/ recent years only use forged pistons (slight better edge against detonation which may occur) and roller cams (especially for warranty/ protection from a "questionable/ improper/ inadequate break-in of new flat-tappet cam). The customer needs pony-up for these rebuild minimums...

 

[Jerryl]

............ I wonder if the "Hyper material" has changed over the years and are now better then 5-10 years ago.

Still wondering ..........

 

[Dreamcar86]

anybody else using hypers??

My last engine had the speed pro's and never had a problem. If I could only say that for the headgasket.

 

[turbofabricator]

Still wondering ..........

Yes.....Hyper's have improved. They have moved the top ring down. The top ring lands "were" prone to failure years ago. Detonation on a Hyper has been known to turn them into pieces in the pan. The factory psiton is, in fact, cast, BUT, they have a steel insert in the top ring land. This alone makes the piston VERY durable. (and very heavy) Speed-Pro/TRW forged are a good piston. But, to meet factory weight, they use a very heavy wrist pin. The TRW pin is nearly solid. It only has a 1/4" hole in it. If $600 won't kill you, go with JE or Diamond forged, with Speed-Pro/TRW in third. Hyper's if you need a budget option when building a 4.1.

 

[87GNSteve]

I spoke too soon

Cracked the piston on #1 cyl.
Just below top ring, at the 2 o clock position travels down to the oil ring and across the inside of the piston to the 11 o clock position.
In all fairness I believe it was caused by inj harness problem, car would idle fine but knock on acceleration. By the time I tried figuring things out; the damage was done --showed 60 psi with all other cylinders reading 149-150 on compression test, injectors flowed within 1-2 cc's of each other.
Oh well, at least it wasnt catastrophic the block and cyl is fine.
Not sure what I am going to do.....I have a few options:
use my 109 on a stand w/ TRW forged slugs.
get a single piston and just bless it and go
get another whole set.
get forged pistons.

(forgive the God awful phone pics please)
PS that major line in the top photo is NOT a crack its part of the casting the crack is visible as the oil ring come around to the pin boss, see it?
but it does travel up ans across in the shadowed area which is not visible in this photo.

 

["Turbo-T"]

Cast and hypers should be banned/outlawed from any engine rebuild kit. They shouldn't be allowed to be sold as aftermarket replacements.

 

[87GNSteve]

Cast and hypers should be banned/outlawed from any engine rebuild kit. They shouldn't be allowed to be sold as aftermarket replacements.

Yes, Down with freedom, Comrade!

 

[PHILBUILT65]

80k and nitrous on a 4.1 still hasent died with a teenage girl driveing it now !!! i think they are ok for some builds phil k

 

[that guy]

I am not at home, but I can take some pics of a cracked hypereutectic piston I have as a paperweight.

Cracked at the middle ring. The block and crank didn't survive.

I haven't used hypers since, but hey do what you want, it's your money.

 

[Nojug]

I bought a car a few years ago w/ a "rebuilt motor" ran car a few times w/ safe tune and blew HG was going to just replace HG but decided to pull motor out and check it over, found speed-pro hypers installed and every one was cracked in the skirt. No damage to block or crank so I installed a set of 30k mile stock pistons I had. Never had a problem w/ stock pistons into the 10's

 

[65malibuss]

I have 0.040" over speed pro hypers in my engine, which is in my 3900 pound Impala that runs high 11's in the quarter mile. I've made over 100 quarter mile runs and thousands of street miles and haven't had any problems. My engine runs cool and I almost never get any knock, except for false knock from downpipe occasionally banging on frame. I've also run over 32 lbs boost a few times with no problems (wastegate puck got rusted shut).

 

[Black Power]

anybody else using hypers??

I am going to in my 4.1, Phil. Mainly because a set of custom forged would have been like 800 bucks. If I am going to spend that much cash on a set of pistons it is going to be for a turbo lsX, if this 4.1 blows up I am going v8.

:biggrin:

 

[65malibuss]

I have 0.040" over speed pro hypers in my engine, which is in my 3900 pound Impala that runs high 11's in the quarter mile. I've made over 100 quarter mile runs and thousands of street miles and haven't had any problems. My engine runs cool and I almost never get any knock, except for false knock from downpipe occasionally banging on frame. I've also run over 32 lbs boost a few times with no problems (wastegate puck got rusted shut).

 

[65malibuss]

Doh!

 

[garrett]

rebuild

I am considering using them on a rebuild that won't see anything more than a TA-49, slightly bigger cam, Razor alcohol, and no more than 21 lbs of boost. I am not wanting to run faster than 12.50 with my T-top 87 GN. With this mild combo, am I OK with these?

 

[PaCemkr86]

I am considering using them on a rebuild that won't see anything more than a TA-49, slightly bigger cam, Razor alcohol, and no more than 21 lbs of boost. I am not wanting to run faster than 12.50 with my T-top 87 GN. With this mild combo, am I OK with these?

they will be fine.. mine hold up to 10 sec passes with pump gas /alky

 

[challengermike]

I ended up going with speed pro forged pistons.

 

[TURBOELKY]

I HAD five cracked hyper pistons.

 

[87GNSteve]

I dont think Hypers are a good idea. I gambled and lost.

See here:http://www.turbobuick.com/forums/general-turbo-buick-tech/257704-catastrophe.html

 

[TurboDave]

I've got hypers in my engine and I'm not worried about it. Keep in mind the factory piston (you know, the one that's gone 10's) was cast.

True, but they were far from ordinary run of the mill cast pistons. A point that a lot of people either forget or didn't know.

Hypers are plenty good for ordinary hot rodding. But NOT for forced induction systems. There's no doubt that some have had good luck with them. But if you push them real hard, better have your tune "spot on". Sure, they might handle detonation at 15#, most will. Will they handle it at 25#+? if there's a hicough in your tune?