Looking for high comp pistons

[SIDEWAYZ]

Im hoping to start my build of my early 1uz. Im planning on 11:1 comp maybe 12:1 with some lextreme stage II cams and some itbs. I am building custom headers. This engine will be backed by a W58 trans. Its going in a first gen celica.

My question is, where can i source some 11:1 or 12:1 pistons??

 

[4U2QUIK]

Wiseco
and, which w58 are you using? most of them barely hold up to stock power.

 

[SIDEWAYZ]

Thanks quik.

Im planning on one from a 90 supra. I dont have any experience with the w58 but i once nade 397whp on a w55 and never had any problems so i was thinking i could expect the same from the 58

 

[4U2QUIK]

w58 from a mkiii won't hold up for long. We've blown up enough to start a small collection over here. You might want to look for one from a sc300 or mkiv supra. They are known for holding 400 hp pretty well

 

[4U2QUIK]

http://www.lextreme.com/forums/showthread.php?t=15217
you may also want to make sure your clutch hub is in good condition

 

[SIDEWAYZ]

Maybe i will attempt to source a r154 from a mkiii turbo then. I made 550whp and 689ftlb in my 88 supra and never had anything but diff cradle problems.

 

[Stratoraptor]

I'm also in the boat looking for high-CR pistons. If anybody can recommend a good source, that would be great.

Also as a side question, should I upgrade the rods, too if I am looking for something <400hp?

 

[krayn]

Rpm will be your killer of rods. Do you plan on boosting it

 

[Stratoraptor]

Rpm will be your killer of rods. Do you plan on boosting it

I don't have intentions on boosting it at least until the next time I take the motor apart.

So the stock post-95 rods are no good at holding say 7500rpm?

 

[krayn]

I dont think so. Not for long anyway

 

[4U2QUIK]

that's funny. Daft innovations 1uz truck has a 98 engine that spins 7800 rpm all day every day. Thr rods will hold fine. Especially if you replace your rod bolts. your biggest limitation will be your valvatrain.

 

[Stratoraptor]

that's funny. Daft innovations 1uz truck has a 98 engine that spins 7800 rpm all day every day. Thr rods will hold fine. Especially if you replace your rod bolts. your biggest limitation will be your valvatrain.

Valvetrain is ported, polished, over-sized, sprung, and cammed. I'm feeling pretty good there.

Rod bolts...is it the rod bolts themselves or threading? Would upgraded bolts say ARP keep the rod from lodging itself somewhere it doesn't belong? I don't want to drop $1000-$2000 on a rod kit if I don't have to.

 

[krayn]

Bolts arnt the problem, its the rod itself, just near the big end. I learnt the hard way.
Your heading into the stage where it snow balls. If you dont change rods you could stuff a set of heads that may owe ya a grand. To do that out comes the pistons. And so it goes on.....
The 98 motor is that a vvti motor?

 

[krayn]

Here is what happend to mine

 

[Stratoraptor]

ouch...how'd you manage to do that?

 

[krayn]

16 psi. Did it for a while though.

 

[Stratoraptor]

hmm...not really looking for FI. As I said, I want to bump up compression.

Should I be worried about valve clearance if my valves are over-sized?

 

[krayn]

To get close to 400 hp nat aspirated will require lots of revs. I dont believe the rods are up to that sort of rpm. As for valve clearance, a dummy assembly and plasticine will tell you about valve clearance. Shouldnt be an issue if valve springs are good and not too bigger lift cams.