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So I have the lsx and have done some logging and as you have stated before lsx pumps have issues at rpm I am seeing good rising oil pressure till like 6500 70psi then it starts to fall off lowest I saw was 50psi at 7200 I don't know if I'm drain in pan I have 7 1/2 quarts in motor. Or is it the pump falling off at rpm. The lsx valley does not seem to have very big drain back holes with valve covers draining back thru valley. I was thing of going dry sump on just scavenge side using stock modded pan 8-10 quart tank and head mounted avaid pump.
Don't know if it's the oil getting to pump . Or pump is issue.
 

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So I have the lsx and have done some logging and as you have stated before lsx pumps have issues at rpm I am seeing good rising oil pressure till like 6500 70psi then it starts to fall off lowest I saw was 50psi at 7200 I don't know if I'm drain in pan I have 7 1/2 quarts in motor. Or is it the pump falling off at rpm. The lsx valley does not seem to have very big drain back holes with valve covers draining back thru valley. I was thing of going dry sump on just scavenge side using stock modded pan 8-10 quart tank and head mounted avaid pump.
Don't know if it's the oil getting to pump . Or pump is issue.
Can you post up the build specs? Since you have an LSX, we can assume lots is not stock in any way. Is it a 427? What heads and other components? piston squirters or no? and so on. Mostly I'm just curious and want to follow along and learn something.
 

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Discussion Starter #4
its a LME 388 lsx with no oil squirters a 10355 mellings pump, callies magnum crank, pro billet h beam rods, diamond pistons coated and gas ported, johnson lifters, stock pan with improved racing baffle, crank scraper and windage tray,brodix heads "has nothing to do with oiling" and che rockers.
 

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So I have the lsx and have done some logging and as you have stated before lsx pumps have issues at rpm I am seeing good rising oil pressure till like 6500 70psi then it starts to fall off lowest I saw was 50psi at 7200 I don't know if I'm drain in pan I have 7 1/2 quarts in motor. Or is it the pump falling off at rpm. The lsx valley does not seem to have very big drain back holes with valve covers draining back thru valley. I was thing of going dry sump on just scavenge side using stock modded pan 8-10 quart tank and head mounted avaid pump.
Don't know if it's the oil getting to pump . Or pump is issue.
Sorry to hear your having issues with your build George, as I know
you attempted to do everything 'First Class'.

First, I would suggest you contact LME, as they built the engine for you.

Second, yes the Iron Block lsX does have oil drain back issues,
which we discussed not long ago within a different thread.

I don't believe I have ever stated that either the LSA or Iron Block lsX has an oil pump issue?
Could you have a cavitation issue, I don't really know (?), but I doubt it!

-just my opinion-
One of the original reasons for GM to build the lsX Block, was for large engine volumes.
And you don't need to spin large volume engines real high to make power..:eek:

With that thought in mind; I continually suggest to those on this forum to go to a 4" Stroke.

If you can't put a bigger blower on it, simply raise / scale the static compression ratio.
The 1.9L Eaton is still going to put out the same volume of air.

-back to the 4" stroke-
This then allows for the same mean piston speed at 6800 rpm's, or 4,533 fpm,
versus ~7600 rpm's to generate 4,588 fpm with the 3.622" stroke.

The longer stroke then turns on the cylinder head sooner, but also turns it off sooner.

So this in a sense, becomes a self limiting rpm limiter, unless you put a set of heads
on the engine that flow a great volume of air.

------------------------------------------------------------------

In another recent thread both Matt and I felt that these engines
begin to have oiling issues above ~7000 rpm's.

With the lsX Iron Block, most likely, your holding a couple of quarts of oil
in the topside of the engine at 7200 rpm shift points.

It belongs in the oil pan, not in the topside of the engine..lol

So a dry sump then should be considered with these engines.
That is, if the engine is going to be operated at something over 6800 rpm' in my opinion.

But, as was stated in another thread; you can't put one in a CTSV,
as there is not room in the engine bay.

So again, I would begin by asing LME what their thoughts are on this....

Good Luck George!
 

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For those of you with interest here is a link to comments regarding the LS Series of Engines oiling issues.

Richard (Tricky Dick) Maskin's owns Dart.

TECH5: Dart's Richard Maskin Discusses LS Engines & Head Design - EngineLabs

-------------------------------------------------------------

When he mentions flowing cylinder heads at 80 inches of water,
that amounts to a velocity of 1,184 feet per second.
 

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Discussion Starter #8
Sorry to hear your having issues with your build George, as I know
you attempted to do everything 'First Class'.

First, I would suggest you contact LME, as they built the engine for you.

Second, yes the Iron Block lsX does have oil drain back issues,
which we discussed not long ago within a different thread.

I don't believe I have ever stated that either the LSA or Iron Block lsX has an oil pump issue?
Could you have a cavitation issue, I don't really know (?), but I doubt it!

-just my opinion-
One of the original reasons for GM to build the lsX Block, was for large engine volumes.
And you don't need to spin large volume engines real high to make power..:eek:

With that thought in mind; I continually suggest to those on this forum to go to a 4" Stroke.

If you can't put a bigger blower on it, simply raise / scale the static compression ratio.
The 1.9L Eaton is still going to put out the same volume of air.

-back to the 4" stroke-
This then allows for the same mean piston speed at 6800 rpm's, or 4,533 fpm,
versus ~7600 rpm's to generate 4,588 fpm with the 3.622" stroke.

The longer stroke then turns on the cylinder head sooner, but also turns it off sooner.

So this in a sense, becomes a self limiting rpm limiter, unless you put a set of heads
on the engine that flow a great volume of air.

------------------------------------------------------------------

In another recent thread both Matt and I felt that these engines
begin to have oiling issues above ~7000 rpm's.

With the lsX Iron Block, most likely, your holding a couple of quarts of oil
in the topside of the engine at 7200 rpm shift points.

It belongs in the oil pan, not in the topside of the engine..lol

So a dry sump then should be considered with these engines.
That is, if the engine is going to be operated at something over 6800 rpm' in my opinion.

But, as was stated in another thread; you can't put one in a CTSV,
as there is not room in the engine bay.

So again, I would begin by asing LME what their thoughts are on this....

Good Luck George!
OK I will talk with LME

I was thinking of doing a scavenge only dry sump they mod the stock oil pan like they do for the T1 cars put 2 oil scavenge ports in bottom of pan and 1 oil feed line to go to
factory pump. The pump mounts to pass head and runs off the factory serpentine belt pulley. then put a lsx concepts lsa blower tensioner to free up space were pump goes.
and mount the oil tank where the washertank is in the cts-v with fill port where washer tank is.
 

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OK I will talk with LME

I was thinking of doing a scavenge only dry sump they mod the stock oil pan like they do for the T1 cars put 2 oil scavenge ports in bottom of pan and 1 oil feed line to go to
factory pump. The pump mounts to pass head and runs off the factory serpentine belt pulley. then put a lsx concepts lsa blower tensioner to free up space were pump goes.
and mount the oil tank where the washertank is in the cts-v with fill port where washer tank is.
I like the way you think..:eek:

If you do that, or something similar, please generate a thread and take many pictures for us!

Cheers
 

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So I have the lsx and have done some logging and as you have stated before lsx pumps have issues at rpm I am seeing good rising oil pressure till like 6500 70psi then it starts to fall off lowest I saw was 50psi at 7200 I don't know if I'm drain in pan I have 7 1/2 quarts in motor. Or is it the pump falling off at rpm. The lsx valley does not seem to have very big drain back holes with valve covers draining back thru valley. I was thing of going dry sump on just scavenge side using stock modded pan 8-10 quart tank and head mounted avaid pump.
Don't know if it's the oil getting to pump . Or pump is issue.
Since you got rid of the piston squirters (reduced oil flow demand) and went with a higher flow pump, you COULD be aerating/overheating the oil at high rpm which might be causing your drop in oil pressure.

Like I said in a different thread, this is exactly what happens when people use too high flow oil pump for their engines in a Subaru and the same concept should apply in an LS.
 

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Since you got rid of the piston squirters (reduced oil flow demand) and went with a higher flow pump, you COULD be aerating/overheating the oil at high rpm which might be causing your drop in oil pressure.

Like I said in a different thread, this is exactly what happens when people use too high flow oil pump for their engines in a Subaru and the same concept should apply in an LS.

If the squirters were to be deleted then we would use a 10296 pump just as in a non squirter block like an LS2/3.
 

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Discussion Starter #13
Ordered a 10296 pump I'll try that first anyone run restricted pushrods standard is .100 hole and the restricted is .050 if not I'll go dry sump scavenging.

George
 

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Ordered a 10296 pump I'll try that first anyone run restricted pushrods standard is .100 hole and the restricted is .050 if not I'll go dry sump scavenging.

George
I would not suggest you restrict oil to the topside on a street
driven vehicle as you could end up with exhaust spring and rocker
arm issues from lack of cooling.

Cheers

------------------------------------------

--EDIT--

I am going to re-state this after considering it;

Carefully restricting the oil to the top side might be something to consider via the pushrods,
however; I would only do it if somebody who had done it before me convinced me it would work.

The heat on the exhaust side of the head, valve spring, rocker arm, valve stem etc.
Require oil to cool them, or considerable damage will occurs to the valve train as i
related just above.

Cheers
 

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If the squirters were to be deleted then we would use a 10296 pump just as in a non squirter block like an LS2/3.
Matt,

It's obvious he's flooding the engine with oil given the oil pressure numbers he has given.

Would you know how much less oil, the pump you recommended will provide for?

Cheers
 

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Discussion Starter #18
So from my calculations I was able to maintain clean oil pressure for 4 sec with no dip that means that there is only 2.5 quarts available in the pan of the 7.5 in the engine with the 9.5gpm pump. The 296 pump will take 1 extra sec to move the same amount of oil but there will be less compounding at the lower rpm.

George
 

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So from my calculations I was able to maintain clean oil pressure for 4 sec with no dip that means that there is only 2.5 quarts available in the pan of the 7.5 in the engine with the 9.5gpm pump. The 296 pump will take 1 extra sec to move the same amount of oil but there will be less compounding at the lower rpm.

George
I am going to have to think about that one for a bit George?

That's a lot of oil top side…....

Cheers
 

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I am going to have to think about that one for a bit George?

That's a lot of oil top side…....

Cheers
Yeah I am sure some oil is getting stuck in the head but I doubt it is enough to empty the whole oil pan causing the drop in pressure.

The lower flow oil pump makes sense as a fix. I bet there is still a benefit to trying out the hybrid dry sump scavenging idea though. I’m certainly interested in that.


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