First 2 days experience...and a couple of questions
Discussion
After getting plates at the weekend I've managed to squeeze a couple of hundred miles in so far - 
- so far, nothing significant to report... oh yes, huge grin every time I go for a drive - maybe I can get some medical help for that! I've couple of questions that someone may be able to answer.
1. Normal oil temperature? (LS7 dry sump with temp sensor in the bottom of the tank). Steady run today (cool weather) saw it steady at about 55-60 deg C. Is this too cold? I've always worked on premise that over 50 C is fine - in traffic it warms up some more - I saw 75 C on Sunday (warm day). Got the standard Ultima dry sump kit, and cooler set up.
2. Limited revs on new (standard LS7) engine... I've imposed 4k rev limit for first 1000 miles to settle her in...can't find anything definitive re this? any thoughts?
3. Water temp - steady at 80 Deg C - Seems ok to me. Was a bit warmer at 85 C intitially but found swirl pot was not brimmed. - so suspect a little air lock was affecting it.
4. Fuel gauge was all over the place. Investigations revealed right tank sender was duff. Stripped down and found the dip tube wire was broken. Resoldered, tested dry and set up dry before re inserting. Resistance readings are similar to factory numbers (they weren't initially) - and gauge is fine now - for new builder I'd say be very careful handling once the pins are out - I'm sure I was, but I suspect it doesn't take much of a bash for the wire to be broken by the float initially.
A couple of rattles to seek out and sort this week, recheck ride height and tracking which seems ok (well, ok for string and home garage set up!) then more big smiles.
Any thoughts welcome
Cheers
Paul
- so far, nothing significant to report... oh yes, huge grin every time I go for a drive - maybe I can get some medical help for that! I've couple of questions that someone may be able to answer.1. Normal oil temperature? (LS7 dry sump with temp sensor in the bottom of the tank). Steady run today (cool weather) saw it steady at about 55-60 deg C. Is this too cold? I've always worked on premise that over 50 C is fine - in traffic it warms up some more - I saw 75 C on Sunday (warm day). Got the standard Ultima dry sump kit, and cooler set up.
2. Limited revs on new (standard LS7) engine... I've imposed 4k rev limit for first 1000 miles to settle her in...can't find anything definitive re this? any thoughts?
3. Water temp - steady at 80 Deg C - Seems ok to me. Was a bit warmer at 85 C intitially but found swirl pot was not brimmed. - so suspect a little air lock was affecting it.
4. Fuel gauge was all over the place. Investigations revealed right tank sender was duff. Stripped down and found the dip tube wire was broken. Resoldered, tested dry and set up dry before re inserting. Resistance readings are similar to factory numbers (they weren't initially) - and gauge is fine now - for new builder I'd say be very careful handling once the pins are out - I'm sure I was, but I suspect it doesn't take much of a bash for the wire to be broken by the float initially.
A couple of rattles to seek out and sort this week, recheck ride height and tracking which seems ok (well, ok for string and home garage set up!) then more big smiles.
Any thoughts welcome
Cheers
Paul
Paul if you get a air lock it will be temp through the roof, not just a couple of degrees. When you look for rattles pay attention to were the roll bars go through the body back to the frame. I had interferance there and it sounded horrible. What ever thermostst temp you have in the motor, at the temps you are seeing in England right now it should run very close to that. Be advised my stock gauge was off at least 6 or7 degrees high so don't get to wound up if all you are using is the stock sensor system. Enjoy your new toy. Lee
There is no cure for the ear to ear grin. Nor would I want one.
As your engine would have been given a good thrashing on the dyno any further tenderness on your part is not required, in fact, the general consensus with the Chevy engines is that you 'Break' them in rather than the 'Run-in' technique of old. A rev limit is however not a bad idea for someone not yet used to the car and these levels of power. Still scares the $hit out of me after running it for 6 years.
The oil could do with being warmer. Ideally higher than the water temp. Do you have an oil thermostat fitted?
There has been debate in the past about where to read the temp. One school says read it as it exits the engine so you know how hot things are getting in the engine. Another says read it as it enters the engine so you know how well your system is managing the oil temp. I favour the latter on the basis that if the oil returning to the engine is too hot then it is time to shut down. If your sensor is close to the point where the oil exits to the engine then that would be fine in my book.
Either the LS7 does not run very hot or your system is over-cooling it.
Steve
As your engine would have been given a good thrashing on the dyno any further tenderness on your part is not required, in fact, the general consensus with the Chevy engines is that you 'Break' them in rather than the 'Run-in' technique of old. A rev limit is however not a bad idea for someone not yet used to the car and these levels of power. Still scares the $hit out of me after running it for 6 years.
The oil could do with being warmer. Ideally higher than the water temp. Do you have an oil thermostat fitted?
There has been debate in the past about where to read the temp. One school says read it as it exits the engine so you know how hot things are getting in the engine. Another says read it as it enters the engine so you know how well your system is managing the oil temp. I favour the latter on the basis that if the oil returning to the engine is too hot then it is time to shut down. If your sensor is close to the point where the oil exits to the engine then that would be fine in my book.
Either the LS7 does not run very hot or your system is over-cooling it.
Steve
Agree your oil is a little cold, 80DegC+ would be your target.
Take your rev limit off. Start building up revs, by 1000 miles you should be using full revs! As Steve said, if it has been on a dyno you should not worry so much, 90% of the 'running-in' will have been done before you turned the key. Treating it with kid cloves is not the right approach with a modern engine
Take your rev limit off. Start building up revs, by 1000 miles you should be using full revs! As Steve said, if it has been on a dyno you should not worry so much, 90% of the 'running-in' will have been done before you turned the key. Treating it with kid cloves is not the right approach with a modern engine
Link to installation guides for GM crate engines:
http://www.gmperformanceparts.com/Extras/engine-in...
Unfortunately they don't seem to have one for the LS7? The other LS engines all seem to contain these instructions though:
5. When possible, you should always allow the engine to warm up prior to driving. It is a good practice to allow the oil sump and water temperature to reach 180°F before towing heavy loads or performing hard acceleration runs.
6. The engine should be driven at varying loads and conditions for the first 30 miles or one hour without wide open throttle (WOT) or sustained high RPM accelerations.
7. Run five or six medium throttle (50%) accelerations to about 4000 RPM and back to idle (0% throttle) in gear.
8. Run two or three hard throttle (WOT 100%) accelerations to about 4000 RPM and back to idle (0% throttle) in gear.
9. Change the oil and filter.
10. Drive the next 500 miles (12 to 15 engine hours) under normal conditions. Do not run the engine at its maximum rated engine speed. Also, do not expose the engine to extended periods of high load.
11. Change the oil and filter. Again, inspect the oil and oil filter for any foreign particles to ensure that the engine is
functioning properly.
I checked a Corvette owners manual and it basically had an abbreviated version of the above.
http://www.gmperformanceparts.com/Extras/engine-in...
Unfortunately they don't seem to have one for the LS7? The other LS engines all seem to contain these instructions though:
5. When possible, you should always allow the engine to warm up prior to driving. It is a good practice to allow the oil sump and water temperature to reach 180°F before towing heavy loads or performing hard acceleration runs.
6. The engine should be driven at varying loads and conditions for the first 30 miles or one hour without wide open throttle (WOT) or sustained high RPM accelerations.
7. Run five or six medium throttle (50%) accelerations to about 4000 RPM and back to idle (0% throttle) in gear.
8. Run two or three hard throttle (WOT 100%) accelerations to about 4000 RPM and back to idle (0% throttle) in gear.
9. Change the oil and filter.
10. Drive the next 500 miles (12 to 15 engine hours) under normal conditions. Do not run the engine at its maximum rated engine speed. Also, do not expose the engine to extended periods of high load.
11. Change the oil and filter. Again, inspect the oil and oil filter for any foreign particles to ensure that the engine is
functioning properly.
I checked a Corvette owners manual and it basically had an abbreviated version of the above.
Thanks for the replies gents, most helpful...
I think my water temp is fine - at about 80 ish and steady.
Oil at 55-60 is at the bottom of the LS7 sump tank, after cooling so maybe that's ok - I'll investigate further - was expecting temp similar to the water in the engine block... All my previous cars have been wet sump and measure oil temp in the gallery or cooler return so I'd expect it to be a bit warmer than in a seperate tank.
Sounds to me as if you are accepting the temp as is.
This is not a good idea. Unless the oil gets well up in the temp range any water/condensation will not boil off and will cause problems in the engine. This is why engines that are run just down to the shops and back get the mayonnaise in the oil. In that case the engine is not getting up to temp to boil it off.
Steve
This is not a good idea. Unless the oil gets well up in the temp range any water/condensation will not boil off and will cause problems in the engine. This is why engines that are run just down to the shops and back get the mayonnaise in the oil. In that case the engine is not getting up to temp to boil it off.
Steve
spatz said:
the company I bought the engine from is recommending 100 degree oil temperatur, so 55 seems way too low and Steve is a 100% right
Talked to my engine man today and I'm not too concerned. Another cool day and 60 deg C at the very coldest part of the system doesn't seem too bad. I plan to measure the oil temperature at the filter and top gallery then the return scavenge temperature (which I agree will be much higher). Once I've checked throughout and know what the respective readings are I guess it doesn't really matter where my sender is as long as I know what it should be at that point. I've the Ultima dry sump kit with cooler - may cover the cooler to help lift the temp if need be.
I am measuring the oil temp at the cover plate of the cam valley, and I can imagine that in normal road use I do not need an oil cooler at all. If I ever trash it around a track I can remove the oil cooler cover easily. Will know soon once I get a chance to drive the car, fingers crossed......
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