442rocketdave

Me too my current engine is .060over and I having it align honed and new studs and I am trying to pick which Halo I am going to run. I am going to open up the clearances a little also I could see some touching spots from crank flex so I am going to run 3.5 on the mains and 3 on the rods with the clevlite bearings. it cost alot but like you I had many many years of racing on the last rebuild and it pays to do it right. I am also saving my money for the dyno for the breakin and dyno tune. 600 bucks plus!! I better have about 800 cause I am trying a couple of different carbs with spacers. That way I know before I go to the track.

380 Racer

Yup some damn good ideas there!

cutlassefi

Who's going to dyno it?

And I wouldn't open up the clearances too much, at some point you'll need some oil pressure. The better the parts you use the less extra clearance you'll need.

442rocketdave

the engine shop here has a dyno, Express Engines and John has been doing it for a long time, I wont open the clearances up to much I am using Clevlite bearings and speed pro rings the bearings have the coating on them they cost me alot but John said they are worth it. I have always used clevlite 77 bearings with good results. Mark whats your optimum bearing clearance?

507OLDS

A few specs on the 507. N-crank stroked to 4.550",Eagle BBC 6.800" rods,Ross +.060 Pontiac 455 pistons(4.211" bore).990" pins.70 455 block with stock caps & straps.
rod journal size = 2.1996"
rod bore size with bearing = 2.2021"
main journal size = 2.9898"
main bore size with bearing = 2.9933
crank end play = .004"
piston bore clearance = .005"
piston to deck .048"
rod side clearance = .018"-.020"
cam end play = .005
main #1 = .0035"
main #2 = .0037"
main #3 = .0039"
main #4 = .0037"
main #5 = .0039"
rods = .0025"
I must run 20/50 oil to get any pressure hot.With the 20/50,it goes down to about 10psi hot idle.

There are better parts & a bigger selection of parts to build these now.This thing is 14yrs old.

cutlassefi

I normally run a little less than Brian has on the mains, down around .003 on 1-4 and closer to .004 on the rear. Rods are good at .0022-0025.

I did the loose clearances 5 builds ago and had the same problem as Brian, low oil pressure.
BTR says that's not a problem but at some point you need oil pressure.
And the integrity of the parts used, i.e. rods etc., is what dictates your clearances. No reason why you can't get by with those rod and main clearances when using Eagle rods and strapped and studded mains.

I used .003 or so on the mains and .002-.0022 on the rods on the latest build, the 434 DX. no oil pressure problems whatsoever. 30-70psi with 10w-40 at full temp.

507OLDS

Just to clarify,so no confusion,the 507 was built by Travis Quillen,using all the toys at Jim Butler Performance.Absolutely no regrets.He knew the oil pressure would be low,thick oil needed,even before it was assembled,but that is how he wanted it. I know Bill has his own ways of skinning the cat.My new engine is a completely different animal.

380 Racer

I agree with Mark, for every inch of diameter .001 and then add another .0005 for racing on both mains & rods. About 65-68 psi going down track with 35 at hot idle.

pax442

I had John at Rocket racing build my 496! He does good work! I bought the stroker kit through summit. At the time it was new! I got one of the first kits with the stroked crank. John had to do some work to the crank. also, the rod bearings that came in the kit were for a big block chevy.

It's a 73 455 block bored 60 over. 10.8 compression. I am using his main caps and arp studs. his dad ported my e-brock heads and installed larger intake valves. they flow 317@700 and 217@700. I had andy at opp grind me a solid cam (250/260 584/592) on a 112 lsa. This cam works well with my power brakes. I just changed manifolds from the torker to the air gap and added a q850 carb.

The car is a 69 cutlass supreme with full interior. tci 400 trans 3500 coan converter with 355 gears. ran 11.68 fathers day at byron with still more left in it. Have not drag raced in 20 years! learning curve.

This motor has been in my car for three years now! I beat the crap out of it all the time! Oil pressure is 60 p.s.i cold. when it gets hot it drops to 20 p.s.i. at idle and then follows the rpm of the engine up to 50 p.s.i. 20/50 royal purple.

Great street engine.

cutlassefi

Sounds like a nice build but why would you post flow numbers at .700 lift yet your cam isn't even within a .100 of that.
I get a kick out of guys that post stuff like that. What's it matter, it'll never see that.

Whatever.

507OLDS

Because the bigger the flow number,the more attractive they look. I am more concerned with low-lift numbers.

cutlassefi

Oh I know. Like I said I get a kick out of guys who post flow numbers at lifts above .600 for a street car. What's it matter.
It's just like the guys who post dyno numbers at real cool water out temps with underdriven water pumps etc. It's all BS.

drjr56

Happy that flows @ certain lift was addressed...I thought there was more to it and I just didn't know.