Nice thunder stick!

 

Can't wait to see ver 2 finished!

 

Awesome Darth! Making progress.

 

Hows progress?

 

Block is getting line honed bores are all finish honed. Should be sizing bearings sometime this week.

 

OK, so all the machine work is done, and we are now at the sizing bearings stage. Big shout out to Chevelle for helping with all this. Ordered a bunch of kits to split them and get the bearing clearances exactly where we want them.

 

Good to see things are moving along nicely.

 

I just started fitting bearings last weekend. Rods case in at .0021-.0024 which needed .001 tighter.

I only got one set of shells in the rear main and the thing needs an align hone .0003 in the vertical and .003 on the angle.

Where are you setting your clearances?

 

My aims are .0023-.0025 for the mains and .0017-.0019 for the rods. I had to line hone also, but I don't remember off the top of my head how far out it was. I'm running a DOD oil pump for tons of pressure. I'll be running 5W30.

 

Is there a specific oil viscosity you need for certain clearances?
I know tighter clearances need thinner oil and looser clearances need thicker oil but is there a way to know for sure what you need?

 

Sweet! I just went to 5W40 mobil1 euro blend in my LS2 and I like it so far. I've always had pretty low oil pressure, but it has lived 20k+ miles now bouncing off a 7200 limiter. I always ran 5W30 mobil1 before that. Hot idle pressures would get down to 12-15. When REALLY hot I was like 40-45 psi in the upper revs. Bearing clearances are on the tight side which has always confused me why pressures are low. Oil pump is a ported ls6/ls2 pump. The Euro oil seems a little more resilient with heat and brought pressures up both at idle and high rpm.

For the ls7 I was shooting for .0022-.0024 on the rods so I'm happy with where they landed. Mains will probably be in a similar range, maybe a little looser. The aluminum blocks really open up bearing clearance when they heat up.

On the LS7 I'll have an external oil pump. For our drag LS engines running 7500+ rpm we've had excellent luck with a truck DOD pump ported. Maintains 60-80psi with 0w20 lucas race synthetic. For the LS7 I want to do a full mile and don't trust any of the in block wet sumps at 7500+ rpm for that long. I really wanted to dry sump it but I just don't have room in the engine bay of my Mazda.

 

I'm honestly the wrong person to ask that question. Maybe someone like KCS or Chevelle will chime in to answer that. I am going with recommendations received.
Funny you say that. I was actually wondering about running 0W20 with the DOD pump, but in the end, I just don't think I trust it. With my compression, I may run 0W30 just to help when it's cold. A lot of resistance from cold compression. My cranking compression before the motor went was 240 psi, and I think it's going to be even higher on a fresh bottom end. I'm actually really curious to see what it is...

I switched from M1 to edge a couple years back. It made my valvetrain quieter. I think is was Dr Whigham who pointed me in that direction. I've also liked the AMSoil 0W30 product very much.

Before all this started, I was holding 55 psi warm idle with the DOD pump and 5W30 oil. In some ways, i wonder if this was masking symptoms...?

 

Lol with the ported DOD pump and normal oil the gauge would peg 100psi until about 1000 ft and then would start to pulse and drop a little. Not sure if it was aerating the oil or just getting hot from pumping so hard through the run but it was consistent and never hurt itself. The race oil is worth some power we've verified it on the engine dyno, but not meant for higher mileage. Appropriate oil weight is more about the clearance and width of the bearings vs pressure. I'd stick with 30W if you're near stock clearances.

 

I run the Euro 0W/40 in my SBE LS3, based on the idea that it's the factory fill for harder usage than "normal" US usage. I consider even my old-guy-driving-around-usage "harder" than normal ... I *do* get on it on a semi regular basis.

 

Change in plans. Now being advised to aim for .0025 both mains and rods. Pump I am running will be fine I think.

I really am very uneducated on bottom end. Enjoying reading the experience you guys have.

 

To help clear up some possible confusion for those of you following along, I originally was going to shoot for .0017-.0019 on rods. That’s where my target numbers were for my 434 build and I was going to mimic those numbers here in Darths build. After consulting with my shop owner, who works with Joe Gibbs and several other top race teams in many other classes including 24 hour endurance teams and Baja 1000 teams, I decided to bump the rod numbers on up to .0024-.0025 to allow a little better cushion due to the power numbers this engine will see, quite a big compression number, and RPM, as well as potential possible detonation that would easily hurt rod bearings seeing the type of load this engine will produce.
The engine would be fine with the prior target numbers mind you, were it a simple 500-600 hp build. Not the case here.
I’ve been ridiculously busy with my business for the last several weeks, and I haven’t had the extra time to speak with Darth a whole lot. We’ve both been eagerly awaiting for vendors and my machinist to get me the stuff ready to go, and in the meanwhile I neglected to share with Darth the change of plans regarding rod clearances. I picked up everything Tuesday of this week from the shop and I’ve only been able to get a couple hours each evening on it. Rod bearings are sized (I have a drawer full of different sizes) and I’ll get the mains figured out Saturday. Should get block and parts clean and hopefully start cutting rings Sunday afternoon if yard work doesn’t creep up. My son plays high level travel baseball and we are started back here in North Georgia, and have a game Saturday evening which will cut into some of this. Anyhoo, as most of you here know, I’m a perfectionist and will get the shortblock back to Darth as quick as I can. I am honored to be able to help get Darth off the jack stands and hopefully hit big power numbers with what Tony has done to the top end.
This engine will use a Melling 10355 pump, which is plenty of pump to keep pressures up where they need to be with this build.

 

These are what clearances im running. Do you allow more for alloy blocks?

 

Mick, an aluminum block will grow .0010ish, where as a steel block will usually grow .003-.004. on average.

 

Thanks Scott, So would you think im a little on the tight side being iron block and running .0025 mains , rods are .0027

 

Thanks for chiming in and clearing up all the clearances!

FWIW - I understood the melling 10355 to be the DOD replacement pump from melling.