engine clearances

[loreak]

ok im about to have my local machine shop build my motor, after digging through some posts and looking around i got a few questions

what cylinder wall clearance clearance should i have him set it to, im going with ross forged pistons .020 over

should i use arp mainstuds, on a few sites ive been looking at that have reassembled race blocks they seem to only do arp rod bolts, but not the main studs

 

[92redman]

As far as boring the block with forged pistons, most manufacturers have the clearances built in already. You should contact the piston manufacturer for that info, but they will probably say they are set up for exactly .020" bigger than factory.
Wait, I take that back, I see you are using Ross and I know for a fact they already have the clearance built in.

 

[1fast97gsx]

Yes I have ross .020 over as well. Just have them bore it and hone it to .020

 

[bigjangin]

bring in your pistons when you bring in the block. Go with the piston to wall clearance Ross specifies, most likely it will be around .005" but it can vary, so call Ross and make sure.

If you are going to use arp mains you have to get mains align honed. For most people stock mains are fine however, as long as you check the main bore and get it align honed as necessary.

 

[NDgsx]

I highly recomend against ARP mains. There actual body diameter is smaller than the OE bolts, this allows the main caps to walk. You'll find this out when you tear down a block with ARPs and see shiny metal on the cap surfaces.
CRCO makes a dowel kit to stop this, but on a 6 bolt you have to ream the hole slightly. If the thrust main is reamed slightly off the bearings will not be aligned properly at the parting line. No standard machine shop is equiped to accurately machine the thrust surface true afterwards either. It's not worth it IMO. I know people trapping over 140 with stock mains without problems.

 

[loreak]

well that explains why slowboyracing doesnt have them listed on their race engines, cuz stock are strong enough and from what you said about them being smaller then oem

that saves me some bucks so ill just go with arp rod bolts

im going with the 8.5:1 ross forged pistons on stock 6 bolt rods, with clevite bearings and arp rodbolts, i think that should handle anything ill throw at it.

anyone else running the same setup? i was wondering how much of a difference in power just going from the 7.8 to 8.5 would make

 

[Cesar]

That's what I"m aming for... 8.5.
except I'll be using 2nd gen pistons on 7 bolt rods in a 6 bolt (crank) motor...(trying to save money.)
I figure I won't really need beefy rods since I've only got a evo3 running 11psi on 94 octane. (stock intercooler, no bs shafts. )

What do you guys think about my bugdet built up??

 

[loreak]

ive got a new oilpump case and balance shaft removal kit going in as well, and i just put in prothanes on all 4 motor mounts, its gonna be interesting

although, why would you go with 7bolt rods in a 6 bolt motor? i mean it would cut the cost of machineing the pistons to fit the rods i guess, but its only like 100 bux to have them machined, or less

 

[kpt4321]

ive got a new oilpump case and balance shaft removal kit going in as well, and i just put in prothanes on all 4 motor mounts, its gonna be interesting

Bump the idle to like 850, and it will be nice and smooth.

 

[1fast97gsx]

That's what I"m aming for... 8.5.
except I'll be using 2nd gen pistons on 7 bolt rods in a 6 bolt (crank) motor...(trying to save money.)
I figure I won't really need beefy rods since I've only got a evo3 running 11psi on 94 octane. (stock intercooler, no bs shafts. )

What do you guys think about my bugdet built up??

I don't think you can put 2g rods in a 1g motor....

 

[Cesar]

your right, you can't. I've got eagles now...