Piston to wall clearance worries
Thread Starter
Registered User
Joined: Jun 2003
Posts: 584
Piston to wall clearance worries
Well the machine shop called me today about my piston to wall clearance, hoping you guys can cheer me up.
I have a virgin standard bore late model block with a few hundred miles on it, so I purchased a set of standard bore Probe Industries forged pistons assuming that the hone would set the piston to wall clearance up to where it needs to be with a forged piston (I know, never assume
).
Well apparently my Probe pistons are pretty tight, and the factory GM hone was to 2 thousandths.
Probe recommends 2-3 thousandths clearance for naturally aspirated applications and 3-4 thousandths for Nitrous/Blown applications.
I decided on 3 thousandths clearance because I plan on running some juice (150 horsepower'ish), but the machinist told me today it looks like the piston to wall clearance is going to come in at 4 thousandths.
Should I even be stressing about this? This is a very limited use street car, mostly just driving it to the strip and occassional cruising. He said I might have some piston slap on cold starts and to stay out of the throttle until it fully warms up, any other downsides to this? Cheer me up guys
...
I have a virgin standard bore late model block with a few hundred miles on it, so I purchased a set of standard bore Probe Industries forged pistons assuming that the hone would set the piston to wall clearance up to where it needs to be with a forged piston (I know, never assume
).Well apparently my Probe pistons are pretty tight, and the factory GM hone was to 2 thousandths.
Probe recommends 2-3 thousandths clearance for naturally aspirated applications and 3-4 thousandths for Nitrous/Blown applications.
I decided on 3 thousandths clearance because I plan on running some juice (150 horsepower'ish), but the machinist told me today it looks like the piston to wall clearance is going to come in at 4 thousandths.
Should I even be stressing about this? This is a very limited use street car, mostly just driving it to the strip and occassional cruising. He said I might have some piston slap on cold starts and to stay out of the throttle until it fully warms up, any other downsides to this? Cheer me up guys
...
Registered User
Joined: Feb 2005
Posts: 201
From: los angeles
Re: Piston to wall clearance worries
youll be OK; i dont even put my car into gear until oil is 160, so even if you have a loose race motor,if youre nice to it when cold, you should be ok.
I was doing a budget SBC for a friend's nitrous grenade and had a long talk with the Probe rep. at the Winternats.My 5 liter buddies love their stuff for affordable pistons[they say 200shot/ 10lbs max.]. He said you can run em tighter than TRWs and their quality control is better, but i have yet to use a set in a motor as SRPs are priced so well.any opinions from guys that have run/ heard of running a set??
more random info from stealth...
oh yeah and if youre running a 5151 kit for your spray[3d gen kit im guessing];200 works but runs dangerously lean, 175-185 is much safer on that bar and almost as fast--pm me for the great jet tune on that kit,ive got some time on it back in the day.
I was doing a budget SBC for a friend's nitrous grenade and had a long talk with the Probe rep. at the Winternats.My 5 liter buddies love their stuff for affordable pistons[they say 200shot/ 10lbs max.]. He said you can run em tighter than TRWs and their quality control is better, but i have yet to use a set in a motor as SRPs are priced so well.any opinions from guys that have run/ heard of running a set??
more random info from stealth...
oh yeah and if youre running a 5151 kit for your spray[3d gen kit im guessing];200 works but runs dangerously lean, 175-185 is much safer on that bar and almost as fast--pm me for the great jet tune on that kit,ive got some time on it back in the day.
Last edited by stealthblack; May 5, 2005 at 09:34 AM.
Thread Starter
Registered User
Joined: Jun 2003
Posts: 584
Re: Piston to wall clearance worries
Originally Posted by stealthblack
youll be OK; i dont even put my car into gear until oil is 160, so even if you have a loose race motor,if youre nice to it when cold, you should be ok.
I was doing a budget SBC for a friend's nitrous grenade and had a long talk with the Probe rep. at the Winternats.My 5 liter buddies love their stuff for affordable pistons[they say 200shot/ 10lbs max.]. He said you can run em tighter than TRWs and their quality control is better, but i have yet to use a set in a motor as SRPs are priced so well.any opinions from guys that have run/ heard of running a set??
more random info from stealth...
oh yeah and if youre running a 5151 kit for your spray[3d gen kit im guessing];200 works but runs dangerously lean, 175-185 is much safer on that bar and almost as fast--pm me for the great jet tune on that kit,ive got some time on it back in the day.
I was doing a budget SBC for a friend's nitrous grenade and had a long talk with the Probe rep. at the Winternats.My 5 liter buddies love their stuff for affordable pistons[they say 200shot/ 10lbs max.]. He said you can run em tighter than TRWs and their quality control is better, but i have yet to use a set in a motor as SRPs are priced so well.any opinions from guys that have run/ heard of running a set??
more random info from stealth...
oh yeah and if youre running a 5151 kit for your spray[3d gen kit im guessing];200 works but runs dangerously lean, 175-185 is much safer on that bar and almost as fast--pm me for the great jet tune on that kit,ive got some time on it back in the day.
. Thanks though!
Banned
Joined: May 2003
Posts: 6,661
From: LA (lower Alabama)
Re: Piston to wall clearance worries
Originally Posted by stealthblack
youll be OK; i dont even put my car into gear until oil is 160, so even if you have a loose race motor,if youre nice to it when cold, you should be ok.
I was doing a budget SBC for a friend's nitrous grenade and had a long talk with the Probe rep. at the Winternats.My 5 liter buddies love their stuff for affordable pistons[they say 200shot/ 10lbs max.]. He said you can run em tighter than TRWs and their quality control is better, but i have yet to use a set in a motor as SRPs are priced so well.any opinions from guys that have run/ heard of running a set??
more random info from stealth...
oh yeah and if youre running a 5151 kit for your spray[3d gen kit im guessing];200 works but runs dangerously lean, 175-185 is much safer on that bar and almost as fast--pm me for the great jet tune on that kit,ive got some time on it back in the day.
I was doing a budget SBC for a friend's nitrous grenade and had a long talk with the Probe rep. at the Winternats.My 5 liter buddies love their stuff for affordable pistons[they say 200shot/ 10lbs max.]. He said you can run em tighter than TRWs and their quality control is better, but i have yet to use a set in a motor as SRPs are priced so well.any opinions from guys that have run/ heard of running a set??
more random info from stealth...
oh yeah and if youre running a 5151 kit for your spray[3d gen kit im guessing];200 works but runs dangerously lean, 175-185 is much safer on that bar and almost as fast--pm me for the great jet tune on that kit,ive got some time on it back in the day.
I have used their parts and pistons for 10 years with NO issues. Thats on Ford & Chevy BB & SB.
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