LS7 Crate Engine Track Use Upgrades

[Walter]

Hello:
It seems that LS7s are popular amongst builders in this community.
The oil pressure of the crate LS7 in my RCR40 is too low for safe operation at higher rpm (hot just 20 to 25psi at almost any rpm level above 1000rpm, tested at the sender as well; cold start ~80psi) The engine is from around 2007 and has about 2000km on it. The problem became very! obvious upon my first oil change using 5W30 oil. The engine will come out and be inspected for the source(s).

In the process of building up the engine I'd like to take the opportunity to make it race track worthy. I'm happy with the stock performance regarding hp and torque. I want to make it reliable.

Two questions:
a - Does anybody here have first-hand experience with the stock LS7 for track use?
(Similar to this: https://ls1tech.com/forums/generati...05-history-issues-ls7-engine-road-racing.html ?)

b - What upgrades would you recommend upon the rebuild? (I was thinking the Katech uprated oil pump, valve seat machining, new valve guides. Possibly the exhaust valves and a better sump (Currently I use the Aviaid baffle.) ? Also the con rods need attention regarding wrist pin tolerances along with blueprinting of the engine.

Greetings, Walter

 

[joe]

I had a bone stock 2015 Z/28 that I drove on the street as well as the track. No problems at tracks like Road America. I put a few thousand miles on it until I sold it at the peak during COVID.

 

[Walter]

I had a bone stock 2015 Z/28 that I drove on the street as well as the track. No problems at tracks like Road America. I put a few thousand miles on it until I sold it at the peak during COVID.

thanks - Road America gave me my first track experience within the Skip Barber School - still my favorite track!

 

[Ed Davis]

Katech did my motor and the upgrades were cam, oil pump, pistons, heads and valve guides. The engine had 6500 mile when rebuilt.
The motor dynode at 640hp. with there 110 cam. Engine has about 8000 miles on it and going great. I used the stock pan with a 10qt tank.

 

[Howard Jones]

Oil temp control. 225-250F max at full song (oil cooler installed in free airflow with good ducting). Near perfect dynamic engine balance job, 1 gram or less. This means a complete disassembly and rebalance including the harmonic dampener and flywheel. You will find your oil pressure issue then. If it's not a sensor issue then there is a clearance opened up somewhere, my guess is a hurt bearing.

Hold revs to take advantage of the torque curve. This means shifting at or just beyond the max torque rev number, not the max rev limit before it blows up. Any engine will last a lot longer running up to 6500 instead of 7500. With 550-600Hp that should be plenty even if you leave 50HP on the table.

I run 50-weight Valvoline R in my track motor. I don't like multi-weight oil for track engines. You really never know what viscosity the oil is.....do you.

note: Is this a new crate motor at the first oil change that only makes 25PSI oil pressure? I would be checking my warranty before I took anything apart. It should be making at least 60 all the time. See the comment about multi-vis oils above.

 

[Larry L.]

I would be checking my warranty before I took anything apart.

Amen... ;-)

 

[Walter]

Amen... ;-)

Warranty? I don't think any luck here - this engine is from ~ 2007 (I believe it was bought from Summit Racing and came with the RCR kit) - also not using GM intake and headers, and taken outside the USA.

12months or 12000miles I believe woukd be the usual warranty.
Anyone who knows better?

 

[Walter]

Does this answer the warranty question:

Warranty

Chevy performance parts Warranty Coverage

www.crateenginedepot.com

 

[Howard Jones]

Sorry, I missed the purchase date. Good luck.

 

[Walter]

LS7 low oil pressure: Culprit identified: one of the cam bearings moved sideways - either poor design in that run/year (~2007) but more likely careless/faulty installation at the factory since bearing OD depends on location. No further damage identified as of now although main bearings look rather used considering that there are only about 2000 miles on the engine.

 

[Mesa]

Low or inconsistent oil pressure could have "done" your crank bearings in short order. I would not be surprised if the rod bearings showed similar wear. In my racing days every time the engine came apart it was standard procedure to replace all the clam shell bearings.

 

[Walter]

Hi: Thanks for your input. All bearings look reasonably well - rod bearings no problem. Cam bearings very good. Main bearings some wear. Oil pump ``like new". The problem is a shifted cam bearing - the cause is up for speculation. An LS7 expert says most likely faulty assembly in the factory. Anyway, problem can be solved.