gnx7

iTrader: (28)

I have an iron 6.0 block at the machine shop with stock crank, Oliver rods, Wiseco thermal barrier coated pistons and A&C boost rings. Running coated ACL bearings.

What are some recommended main/rod bearing clearances?

Ring gaps for #1 and #2?

I'll be running on e85 exclusively and goal is 900-1000rwhp. I'll keep it at around 600-700rwhp for the most part. Street driven but focus is drag strip and 1 mile shootout stuff. Single turbo.

Thank you for your input!

STAR

iTrader: (1)

You need to speak with your engine builder to see what he prefers/recommends, but I think something along these numbers should work well.

mains .027
rods .025

top ring .028
second ring .032

gnx7

iTrader: (28)

those bearing clearances are loose

Any other "advice."

FMX05

iTrader: (3)

I don't have my build sheet in front of me but that sounds pretty close to what mine are in the 390. I think my rods are .003. I was told the iron block doesn't allow as much expansion and therefore run looser clearances than the aluminum blocks. My goals were similar to yours. E-85, 1000whp capability but run between 700 and 800whp most of the time. Street driven with quite a few track passes.

speedracer5532

iTrader: (8)

rods and main - .0018-.0022 is what I like.

*I just forgot the other zero.*

Fbodyjunkie06

iTrader: (10)

Boy those are some big differences in clearances....

I'd like to see Kurt Urban, HKE, LME, AES, or VA speed speak up on this matter, that is if they can or are willing to divulge those clearances.

I guess it wouldn't be that big of a deal if it was a race car that burnt oil, but too loose and you'll have blow by like crazy and/or be adding 1-2qt's every 1000 miles.

Loudmouth LS1

iTrader: (10)

Too loose on the mains and your oil pressure is going to be garbage! We ran my mains at .0015 in my aluminum block, I heard for the iron blocks to go more around .0018 - .0020 since there is not as much expansion. The other thing that is scaring me with what people are saying in this thread is everyone is forgetting the extra 0 in the numbers, haha big difference between .0015 and .015!!! As for rods, I can't remember what my rod clearances were. BTW, this wasn't on a boosted motor, but it was seeing 300 hp worth of nitrous.

Fbodyjunkie06

iTrader: (10)

Lot of crucial info being tossed around in here.

Loudmouth that sounds like a good clearance for the mains. What was your oil pressure like in all situations?

Loudmouth LS1

iTrader: (10)

About 50 cold idle, little over 40 hot idle. Don't remember what it was at wot (usually never looked, too many other things going on to take my eyes off the road, haha), but part throttle driving around was usually 50 - 60.

FMX05

iTrader: (3)

For what its worth I have 60psi cold idle and 45only hot idle with a melling 10296 pump using the lower pressure spring and 20w50 VR1.

I looked mine up. Mains are .0026-.0028 and rods are .003

Loudmouth LS1

iTrader: (10)

Wow, that pump and the 50 weight must make a huge difference! I had a friend with stock ported pump, if i'm not mistaken it was .0022 on the mains and this was also an aluminum block, but when the car got up to temp on 30 weight the oil pressure went to 25 - 30 at idle!

FMX05

iTrader: (3)

25-30 hot is probably very normal. I was told the 20w50 VR1 would be good to use for break in. I plan on trying a 10w40 synthetic after it's broken in although I wouldn't be surprised if I end up back at 15w 50 Amsoil.

blackmagicturbo

iTrader: (2)

with all the stock 5.3s and 4.8 making over 1000 horsepower on stock bottom ends what would be wrong with stock bearing clearances and gapping the rings to the piston ring manufacturer specs ?

FMX05

iTrader: (3)

I wouldn't say it quite like that. Stock bottom end 4.8's and 5.3's making 1000hp aren't hanging out on every street corner. Just because it can be done with stock clearances and ring gap doesn't mean that is ideal. Most of them over 650whp are on borrowed time in one way or another. There are plenty of things we can do to minimize the risk but it is still there because the factory setup is not ideal for that much boosted power. They were built to be 300hp N/A motors after all.

STAR

iTrader: (1)

Found this on ERL's website

http://www.erlperformance.com/images...cBluePrint.pdf

Fbodyjunkie06

iTrader: (10)

Those look spot on for great oil pressure and I'd bet you'd be hard pressed to find a motor ERL builds that has excessive or hardly any blow by or low oil pressure problems.

Fb0dy0nly

iTrader: (10)

Good info in here if you skip thru the bs and other crap....http://www.yellowbullet.com/forum/sh...d.php?t=383678

DeltaT

iTrader: (5)

These are very close to what I ran on my 421" build (I'm assuming he left out a couple critical zeros):

mains .0027 - .0028 nominal
rods .0023 - .0025 nominal

top ring .026
second ring .028

E85, YSi build with room for a little squeeze

Jim

TurboS10

iTrader: (12)

That's for an LS2 Al block build.
Iron block can use a different clearance since the bearing bores won't grow so much.
ERL has some good info on their site on AL growth etc. Worth a look.
From the pictures of my build, it looked to be set up with .0019-.0021 on the mains
for a n/a 7k 600hp 416 LS3. With growth, it should be about .0025-.0028 I'd guess.
Which sounds huge to guys that started out with Al blocks.
Try .0015 on an iron block with some RPM and you'll need new bearings.

Shawn @ VA Speed

iTrader: (3)

wow, alot of crazy numbers being thrown around here. it has been my experience that's it's best to say nothing if you don't have facts and understand how those facts were achieved. For a turbo engine with an iron block the mains should be in the .0023-.0025 range and the rods in the .0025-.0027 range. now sometimes with the stock crank we will run the main a little looser (closer to .0027) to allow for crank flex. But this is something that would need deermined for the particular application. keep in mind when you run looser clearances you need to make sure you have an oiling system that will keep up.