to those with forged pistons in their daily drivers, do you consume much oil, and have you seen your cylinder walls since putting the pistons in? are your cylinder walls worn in any way, from the looser tolerances that are present when the motor is first started? (piston to cylinder wall tolerance as compared to a stock cast piston with tighter tolerance.) thanks for your time.

 

Ive run forged pistonsin all my motors for the last 9 years and never had a problem due to forged pistons and their clearance.

 

yeah but how many different motors in 9 years yo?

 

lets see

89 Mr2 supercharged 1 motor

94 MR2 turbo 1 motor

97 integra 5 motors

 

it also matters what pistons you plan on running, certain manufacturers produce their pistons so as to reduce the "piston slap" problems when running forged pistons due to the different expansion rates of the forged piston, and the iron cyl walls.

My arias pistons have no audible slap, and neither do my friend's JE's, both brand new engines and new design forgings (mine were custom)

IF you have your cylinder clearances, and everything else in place, there should be very little if any piston slap upon a cold start.

If you are still concerned about piston slap, consider having the skirts coated, as to help decrease the chance of cylinder wall/piston marring on cold starts. OR get a block heater, and keep your engine semi-warm all the time.

Brad

 

i had my forged pistons in for over 22K with stock sleeves now. there's a bit of knocking during startup/warmup (especially since there's such cold weather in PA where i live right now ), and sometimes at idle but goes away with higher rpm use/higher temps.

i may be taking the motor apart soon, or at least the head off, so i'll find out what everything looks like.

 

cool! how come nobody runs the mr2 turbo ? it seems like a cool platform for a high boost setup...but it must have some shortcomings?

 

i dont know why. The only problem i ever had was the fuel rail is far too small and the turbo is a hand grenade at high boost. I shattered the exhaust wheel to peices. Other than that its awesome. I could pull low 1.6 60 foot times on street tires

 

can you wedge a bigger turbo in there? i heard it was a mistu 18g turbo? whats the displacement?

i think those cars (the mr2 turbo's early 90s are beautiful)

 

most toyota including the supras used the CT26 which is junk. One thing i forgot to mention is the intercooler sucks and its location is almost jsut as bad. It sits in the passenger side air vent on the side but you dont get enough airflow through there. The engine itself is actually very solid. Its designed by yamaha jsut like the new Celica motors.

 

i'll add this to my list of cars i want but cant own.


sorry! back on topic...

 

funny i just pulled a mr2 engine out yesterday, that was a bitch, we had to pull the motor from the botom.
stock turbo is capable of running 14lbs on pump gas. but my teggy with 7 lbs of boost was still faster? maybe its the higher compresion pistons that hondas are running?

 

not to mention the the IC is punney..even the greddy ic for the mr2 is small. Some people sacrafice their trunk and run a bigger ic with some sort lid to catch the air.

 

The sw20 chassis is quite nice... very very fun to drive with the MR setup... crazy traction as well... which might add to the problem that the transmission has an automatic exploding capability

I saw a few sw20s that tossed the intercooler in the rear trunk area with fans to assist with airflow across it.

 

and dont forget about the syncro problems that all the 1st gen and both the sw20 and sw21 had. Every upshift and downshift involving 2nd or 3rd gear would grind. I rebuild so many transmissions from autocrossing. That is why i sold both of my mister's

 

Are there any upgrades for the transmission? Perhaps a Greddy 6 speed?

 

not that i know. I started to run some syncro stuff from BG and it helped but it would be jsut as bad as it was within 6 months. I ripped the car though. I would autocross the car anywhere. I still have quite a few trophies from that car sitting around.

 

Sorry to continue the OT discussion, but where can I find out more about the Mr2? Is there a forum anywhere? I've always been afraid to buy one because never touched one. From what you guys are discribing they're pretty nice just a few bugs. Kind of like the turbo II's

 

I hung out quite a bit on mr2.com . They have a ton of info on there. They also have a discussion forum.

 

anyone with an on topic opinion? hehe, was kind of curious... i'm about to drop some forged pistons into a non-sleeved block, and was wondering if it would lead to any problems.

 

Back on topic

Yes, I have noticed more oil consumption with forged pistons.

But it could also be a number of things, blow by, valve seals or even gasket "seepage".

tell me how much you are losing

 

on the off topic of MR2's, there is a guy locally putting a GT30 on his MR2. should be a fast street car.

 

i personally will be running B16 pistons in an ls/vtec, i was wondering about oil loss and cylinder wall scarring as a friend of mine would like to get high compression forged pistons for his build. i have two friends with turbo VW corrado's, one with forged pistons in a single cam motor makes a lot of noise compared to the twin cam with cast pistons.

as for the honda's, they will be using stock sleeves, so i am interested in a review of this setup. thanks.

BTW: mr2's are sick.