tpi_roc

Ok, I'm fairly close to building an engine with Hypers just because of how uninterested I am in super/turbo/lots of NoS. BUT, should I be able to find a quality set of forged pistons for a similar price I'd LOVE to do it. So I ask,

Are there any GOOOOOOD forged pistons that are just slightly over the price of hypers? Obviously not JE's, or ROSS, who's got some good forged pistons with close tollerences and streetable compression?

------------------
1985 Iroc-z, 14 second 305, new engine in the works.

onebad82z

iTrader: (7)

Have you checked out TRW's?Not top line of the line forged but for the price very good.I dont think they are that much more than hyper's.

------------------
1982 Z28:355,4 Speed,Lots of bolt ons

tpi_roc

Actually im trying to dig up a page for TRW's as we speak (or at least as I do )
How would they stand up to super/NoS?

------------------
1985 Iroc-z, 14 second 305, new engine in the works.

onebad82z

iTrader: (7)

I would say they would be alright with a 150 shot.Maybe a 200 if you got all clearnces right but that is really pushing it.They will be better than hypers anyway around it.

------------------
1982 Z28:355,4 Speed,Lots of bolt ons

tpi_roc

Does anybody know the compression height of l98 pitsons?

The volume is 12cc right?

------------------
1985 Iroc-z, 14 second 305, new engine in the works.

SoCo80p

iTrader: (5)

right speed pro (used to be TRW) are the cheapest forged you can get, there around 300 or so if your not going to use any power adder then the hyperutectics will be fine for your setup, but if you ever do plan to spray it go forged.

tpi_roc

Forged it is!

------------------
1985 Iroc-z, 14 second 305, new engine in the works.

tpi_roc

TRW it Isn't!

Just spoke with a machinists, said that TRW pistons have very low tollerences (low quality) that one skirt of a piston and the other can be thousandths off very regularly, and that they're heavy pistons for the most part.

What are some opinions on silvolite?

------------------
1985 Iroc-z, 14 second 305, new engine in the works.

RB83L69

I've used quite a few TRW pistons in my engines, I've never seen that degree of quality problems. Of course they're not marketed under the TRW name any more, Federal-Mogul bought that operation and that product line is now branded as Speed-Pro and Sealed Power.

Silvo-Lite is a rebuilder's (read: crap) cast piston, except for their hypereutectics. I have no experience with those however.

I'd recommend the SPs, either the forged ones, or their "Sterling" brand of hypers (that's what's in my little weenie motor right now). Check them all with a mic if you are worried about that, and keep returning them until you get good ones if necessary. Those are all an off-the-shelf part and they come as "eaches" not as a set of 8, so you can do that.

The forged ones are heavier than racing specialty pistons, but lighter than cast. If you're really worried about the weight, get lightweight pins; that's where the weight is, not the piston itself.

------------------
"So many Mustangs, so little time..."
ICON Motorsports

tpi_roc

Thanks for the reply!

I'm not worried about weight, not to much at least. I'm shooting for 400hp, 450 tq, and the machinist I talked to said TRW's were horribly crafted and are pretty much out of business because of it. Which goes along with you saying that they were bought out. I'm not descrimanitive, and I dont really care what "name" is on my piston, I want quality, I want strength, and I'd like it to be light. I wont go blown, and have considered a 100 shot of nos, but nothing more. I was thinking forged because the less times i need to build the engine the better

Real world experience is by FAR the best, and thank you for yours. The problem with buying and shipping back untill you get what you want, sounds like a lot of wasted money in shipping to me

Thanks again!

------------------
1985 Iroc-z, 14 second 305, new engine in the works.

RB83L69

Well if it's defective parts, it's somebody else's shipping But seriously, I haven't had that sort of problem, and I've used quite a few sets of both TRW and F-M's brands of pistons over the years. I honestly don't think you'd have to worry about that.

TRW seems to have changed strategies, it looks to me like they're getting out of the replacement auto parts business altogether. They've sold off practically all their business units that were in that industry over the last 5 years or so. I guess it's not as profitable a business as it used to be....

------------------
"So many Mustangs, so little time..."
ICON Motorsports

tpi_roc

Alright I'll look more at spedpro/trw

know of any good online ordering places OTHER than paw/jegs/summit ?



------------------
1985 Iroc-z, 14 second 305, new engine in the works.

rezinn

I think that each valve relief is 6ccs, so that should be correct.

RB83L69

12cc is about right for .020" of deck clearance, plus .039" of head gasket... I come up with 12.4 cc [pi * (2)^2 * .060" * (2.54 cm/in)^3]

Typical valve reliefs on most TRW-like forged pistons ("double eyebrows") are in the 3.5 - 4 cc ballpark, total per cylinder, on top of the deck clearance and head gasket volume given above.

------------------
"So many Mustangs, so little time..."
ICON Motorsports

[This message has been edited by RB83L69 (edited December 07, 2001).]

chevymad

Just for an idea of how strong the trws are... I built a 350 for my brother using these. Well I had my machinist install hardened seats in the heads. One of the seats worked its way loose and stuck the valve open. The piston hit the valve while the truck was doing 60mph. It blew a 4" hole in the head. You could actually look right through from the chamber out either the intake or exhaust ports. It also split the cylinder wall lengthwise in 5 places. The piston however came out in one piece. Just a few dents in it! I've heard that pistons will have a slight variance. But your machinist is suppose to bore each cylinder to match each piston. Maybe he just doesnt want to spend the time??

tpi_roc

Thats more than likely. But I'd be more comfortable with a company that had extremely close tollerances than one known for slacky ones.

And not knocking your story, that is impressive, i've broken cast pistons in my hand before, but if they're truely forged aluminum and super heated seems they'd tend to be a LITTLE soft, and i can see one denting without breaking considering it has side support all the way around it.

------------------
1985 Iroc-z, 14 second 305, new engine in the works.

giovanhalen

I hear federal mogul is going bankrupt. And I never heard of machining each cylinder for a particular piston. Guess you could have different size pistons on each bank to be different.

RB83L69

F-M has asbestos liability exposure... you'd be astounded at the number of perfectly profitable companies that have "gone bankrupt" ("filed for court protection from creditors" is the correct concept) to limit the ability of these people to pick them clean and provide for an orderly means of handling the claims. I know, I've been the foreman of a federal jury trying an asbestos worker case; if every one of the workers or others who thinks they have a claim were allowed to file their own individual lawsuits, the legal fees alone would bankrupt the companies for real, and the only people who would get anything out of them would be the lawyers. Dow-Corning, Raybestos, and a whole host of other companies are in the same situation as F-M right now.

Anyway, in a typical production-line slap-together "warranty" "crate motor" rebuild, they don't pay any attention to the variation between individual pistons; instead, they slap them together, and hope that enough of them make it out of the warranty period that they still make money. In a true performance "build" (as opposed to a "rebuild"), one of the things that all that "bleprinting" money pays for is making every part match every other part. It doesn't matter whose pistons you use, if you want a premium engine build, you mark which piston is which, and match the cylinders to them individually, to get consistent bore clearance on all of them.

That's why I build my own rather than buying somebody else's mass-produced product, no matter whose product it is, GM or anybody else. That's also why if an engine comes with a warranty, I'm not interested; if it was done right, no warranty would really be necessary, because the odds of failure would be so low.

------------------
"So many Mustangs, so little time..."
ICON Motorsports

toosloz

i have speed pro forged in my motor....and i may spray it with a 150 shot...iam not all oncerned one bit..

here is something to thing about.....if trw is crap...how come the 60's muslce cars were mostly (i think ) with them

chevymad

I think that motor is still laying in dads garage. I should go take some dig. photos of it. Might be cool to show off. Was definately a waste of the $1500 we paid the machinist. He said the rocker arm caused the problem, and that since we bought the rockers from another supplier he wouldnt warranty the work. Hate to tell him we used those same rockers on my other brothers motor the next year. Its still running today. Should have sued, other people around the area are starting to learn about the guy though. He's currently being sued for a $35,000 diesel and the loss of a fishing season by one man. Seems it took him 3 tries to rebuild the diesel and never did get it right.