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[jamez]

I plan on putting higher comp. pistons in my car, i was just curious on whether or not its best to pull the motor out to put in new pistons, or if it can be done by just taking the head and oil pan off... because I will have the head off anyway.. thanks

[924RACR]

By the time you've got the head and oil pan off, the engine basically is out of the car. Pull it, do it the easy way, and have the block cleaned by a machine shop while you're at it...

_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

[Lizard]

i would really suggest pulling the whole engine and if you are putting in higher compression pistions rebuild completely bearing gaskets and all as if you dont redo the bearing you will end up having to redo it later and if you dont replace the gaskets they will blown out or leak (especially the head) you might also concider ringing your pistons so you dont have to worry about blowing the head gasket.

[jamez]

ok, thanks for the advice.

[Lizard]

no prob, while you have the engine ripped apart why dont you bore and stroke it

[jamez]

how much will it cost to have the motor bored and stroked, also what will the horsepower gain be? will the motor still be somewhat reliable?

[Lizard]

the motor will not loose any reliablity from boring and stroking and if you port and polish the head and get a wild cam at the same time as well you will notice a mager increase in power anywere from 20-60+ horse it shouldnt cost that much, up here in canada i would take it too lordco machine shop tell them what i want them bored to and it would probably cost about $60 canadian although i get an awsome discount and as for the stroking different connecting rods to change the stroke and also why not take the crank to lordco and have it lightened and balanced engine will rev faster and more efficently

[924_fan]

I think that stroking an engine is a bit more involved that merely changing the connecting rods.

To stroke an engine the crankshaft needs to be modified. Effectively the rod journals need to be moved. It costs in the $1500 - 2000 USD range to have done. Usually when the rods are changed in a stroked motor they are shorter than stock to avoid hitting the head. The rods themselves have no affect on the stroke.

_________________
Skip Denton
'79 924 Sebring

[ This Message was edited by: 924_fan on 2002-05-22 06:35 ]

[Lizard]

actually the rods do have an effect on it however yes you should adjust the crank as well but that is a very expencive task

[Joes924]

What you do do after pulling it at the least is have the bores honed for sur.

[924_fan]

Stroke is not changed by modifying the length of a connecting rod. It is changed by modifying the distance between the center of the rod journals and the center of the crank journals.

[Paul]

I always install Raceware cylinder head studs, haven't had a head gasket failure since I started to do this!

[-nick]

wow Paul, you don't mess around! i've never heard of anyone having a problem with the stock studs other than having to retorque them often. Raceware studs would definately solve any possible problems. they're a little steep though, eh? i'm curious, do you have to watch the raceware studs as closely for torque?

as for replacing the pistons: you should check on the availability of them first (i assume you're talking about the 9.3:1 set, not a custom JE set?). they can be difficult to find. you're bore may depend on what's available.

i wouldn't recommend boring out anymore than 0.040" max. the cylinders are sleeved and the sleeves aren't that thick. regardless, if you're going to get new pistons, take the block and pistons to the machine shop and have the bores matched.

balancing would be the next place to go while you've got it all apart, but it can get pricey. stroking is generally not an option, as has been pointed out.

good luck and let us know how it goes. engine builders supply (EBS on the web) used to have 9.3:1 pistons. they also are a JE dealer i believe. and new piston sets generally come with new rings, i would never recommend putting old rings into a new piston.

-nick

[Joes924]

I remember when I was getten a free set of euro pistons from a guy in nova scotia all i had to do was pay shipping i didnt do it rightaway and the guy changed his mind gave em to someone else. pistons are spendy one of those places mentioned dont have em any more there like 350.00 to 550.00

_________________
Joe D.from Denver Colorado residing in Oregon

RTFAQ

[ This Message was edited by: Joes924 on 2002-05-31 10:32 ]

[Peter_in_AU]

anyone know what JE charge for a set of pistons?