piston to bore help asap!

[88-7MGTE]

hi i just gave my engine to the machining shop, and i need specs for pistons to bore clerance, does anyone know where can i find that specs, i have a 7mgte block with JE pistons .40 over and eagle rods( balanced to .5 gram)
i just bought the TRSM book on friday last week, and im waiting on the book, but the machining shop guy needs the specs today. By the way the supra TRSM costs now $113 with shipping not $50-$60 if anyone can help please do, i need to call him today with the spcs thanks.

 

[JustAnotherVictim]

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/default.aspx

 

[IJ.]

Should have been a spec sheet in with the JE's but from memory it's 4thou

No use using the TRSM as Forged pistons require different PtoBore than cast.

 

[JustAnotherVictim]

Oh yea he did say JE huh...

 

[IJ.]

 

[p5150]

Always use the specification sheet from the manufacturer because pistons can expand at different rates depending on their material.

Also, make sure you have the measurement correct. As I recall, the JE requires a clearance of .003 - thats .003 on each side, not .003 more diameter than the piston. So that should make the bore .006 larger than the piston.

I could have it backwards though so read your spec sheet.

 

[IJ.]

Can't put my hands on my JE sheet but I'm pretty sure for 2000 series aluminium pistons it was 4 thou total, Ross are 6 thou but rattle when cold if machined to that.

 

[suprahooked]

JE are know for piston slap and my machinist put mine at 3 thous. JE specs 4 thous.

 

[IJ.]

John: Thanks I was pretty sure that was the spec, I run around the 3 but with coatings.

 

[88-7MGTE]

ok thanks i'll let him know that the come with the spec sheet. I have alread gave the block, pistons, rods, crankshaft to the machining shop, what else should i know, so i dont get any problems???

 

[jdub]

From JE's site
http://www.jepistons.com/dept/tech/dl/piston_instrc2618.pdf

 

[suprahooked]

Make sure you get your rear timing belt cover cut with the block and tourque the belt adjuster to 39 lb before he cuts the bore.

 

[88-7MGTE]

JE are know for piston slap and my machinist put mine at 3 thous. JE specs 4 thous.

so what are you saying that .003 would be better, less of a piston slap?
and i wont have any problems with the rings beeing to tight ?

 

[88-7MGTE]

anything else should i know before he starts ?? heehe
me first timer dont want to fuck it up

 

[suprahooked]

Just what my machinist did , You should go with what je spec is if you are worried, Rings get file to je specs

 

[88-7MGTE]

well what do you think its better ? .003 or .004 ? just asking

 

[suprahooked]

Well IJ is running .003 and i am too so you should be safe with .003 but thats your call being je specs say .004. I just dont want to steer you wrong.

 

[88-7MGTE]

Make sure you get your rear timing belt cover cut with the block and tourque the belt adjuster to 39 lb before he cuts the bore.

which bolts are you pointing at ?? the black ones that go around the rer timing belt cove? (i used one of your picture if you dont mind)

 

[suprahooked]

its the belt adjuster bolts it is right in front of #1 cly.bore, you should tighten it to 39 ft lbs before you bore the cyl because if you dont you can distort the bore tighten it. In the pic it is right above the crankshaft is a hole with a off centered circle around it.

 

[spoolint78]

that is the tensioner correct?
i believe the tq spec for that is 36ftlbs