Aussie burnout engine bearing clearances?

General engine tech -- Drag Racing to Circle Track

Moderator: Team

shoedoos
Expert
Expert
Posts: 674
Joined: Wed Aug 09, 2006 3:14 am
Location: New Zealand

Aussie burnout engine bearing clearances?

Post by shoedoos »

Anybody know what clearances the Aussies run in their blown, injected big block Chevy burnout engines?
engineguyBill
Guru
Guru
Posts: 1264
Joined: Fri Feb 26, 2010 11:15 am
Location: Gold Canyon, AZ

Re: Aussie burnout engine bearing clearances?

Post by engineguyBill »

I have no idea what these blokes run for bearing clearance, but cannot see any reason why they would not be running the generally-accepted bearing clearances of .0025" to .0003" OR possibly .0035" to .0004".
Bill

Perfect Circle Doctor of Motors certification
SAE Member (30 years)
ASE Master Certified Engine Machinist (+ two otherASE Master Certifications)
AERA Certified Professional Engine Machinist
MELWAY
Guru
Guru
Posts: 1005
Joined: Mon Dec 04, 2006 7:37 pm
Location: melbourne australia

Re: Aussie burnout engine bearing clearances?

Post by MELWAY »

I have run .003-.0032 rods. And .0035 mains
I have heard of others pushing mains to .004
3370lb Sedan 9.89@136MPH 358chevN/A
KnightEngines
Guru
Guru
Posts: 2682
Joined: Fri Jan 09, 2009 8:51 pm
Location: Australia

Re: Aussie burnout engine bearing clearances?

Post by KnightEngines »

Yeah, I'd be closer to .004" on the mains & .003-.0033" on the rods.
shoedoos
Expert
Expert
Posts: 674
Joined: Wed Aug 09, 2006 3:14 am
Location: New Zealand

Re: Aussie burnout engine bearing clearances?

Post by shoedoos »

cheers guys, any other tricks in keeping one alive? EFI BIg-ugly/14-71 on top of a 427....
lefty o
Guru
Guru
Posts: 3445
Joined: Tue Oct 15, 2013 8:50 am
Location:

Re: Aussie burnout engine bearing clearances?

Post by lefty o »

id sure be on top of windage control, and keeping oil in the pan, ie kickouts.
shoedoos
Expert
Expert
Posts: 674
Joined: Wed Aug 09, 2006 3:14 am
Location: New Zealand

Re: Aussie burnout engine bearing clearances?

Post by shoedoos »

Moroso 21049 pan okay? Or should I be looking at a road race style?
MELWAY
Guru
Guru
Posts: 1005
Joined: Mon Dec 04, 2006 7:37 pm
Location: melbourne australia

Re: Aussie burnout engine bearing clearances?

Post by MELWAY »

Something like that MUST have a dry sump.
I have done many burnout engines. And as soon as you go hat with methanol. It tops them over the edge with wind age and oil control
Also what ign system have you got? Weak spark can cause major issues
3370lb Sedan 9.89@136MPH 358chevN/A
User avatar
FC-Pilot
HotPass
HotPass
Posts: 913
Joined: Tue Mar 17, 2009 2:23 pm
Location: Springtown, TX
Contact:

Re: Aussie burnout engine bearing clearances?

Post by FC-Pilot »

MELWAY wrote: Wed Jun 17, 2020 10:20 pm Something like that MUST have a dry sump.
I have done many burnout engines. And as soon as you go hat with methanol. It tops them over the edge with wind age and oil control
Also what ign system have you got? Weak spark can cause major issues
I was thinking the same thing in regards to oil control. After running injected alky drag stuff, I can’t imagine the oiling issues those things have. Also with a dry sump and good preheating and maybe even pulling vacuum it could keep the oil Stay much cleaner without fuel contamination, therefore helping the oil to continually do its job.

Paul
"It's a fine line between clever and stupid." David St. Hubbins
shoedoos
Expert
Expert
Posts: 674
Joined: Wed Aug 09, 2006 3:14 am
Location: New Zealand

Re: Aussie burnout engine bearing clearances?

Post by shoedoos »

coil on plug through a Link ecu, Moran injectors, staying wet sump....not a dedicated burnout car, just adding insurance with clearances and any other tips etc
MELWAY
Guru
Guru
Posts: 1005
Joined: Mon Dec 04, 2006 7:37 pm
Location: melbourne australia

Re: Aussie burnout engine bearing clearances?

Post by MELWAY »

How hard do you rev it. Is it on e85 or meth
3370lb Sedan 9.89@136MPH 358chevN/A
shoedoos
Expert
Expert
Posts: 674
Joined: Wed Aug 09, 2006 3:14 am
Location: New Zealand

Re: Aussie burnout engine bearing clearances?

Post by shoedoos »

Melway, the thing is being built at present, that's why any tips would be appreciated, presently methanol, but may change to E85. RPMs aren't going to be any where near the Aussie stuff, it has one of those flexy OEM steel cranks in it....more like 5k, blower 10-percent overdrive.
MELWAY
Guru
Guru
Posts: 1005
Joined: Mon Dec 04, 2006 7:37 pm
Location: melbourne australia

Re: Aussie burnout engine bearing clearances?

Post by MELWAY »

I have run those GM steel cranks at 1000hp with no issues they are a good thing with a nice radius on journals
3370lb Sedan 9.89@136MPH 358chevN/A
shoedoos
Expert
Expert
Posts: 674
Joined: Wed Aug 09, 2006 3:14 am
Location: New Zealand

Re: Aussie burnout engine bearing clearances?

Post by shoedoos »

how about piston to head clearance?
shoedoos
Expert
Expert
Posts: 674
Joined: Wed Aug 09, 2006 3:14 am
Location: New Zealand

Re: Aussie burnout engine bearing clearances?

Post by shoedoos »

...also piston to wall clearance as well - would you open them up a bit from manufacturer spec? Any special coatings on the pistons?
Post Reply