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Re: Horsepower loss with Dry Sump??
[Re: Mpetros]
#1441296
05/24/13 09:31 AM
05/24/13 09:31 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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While the dry sump does take power to turn it so does the stock style pump... I've never tested a back to back between them .. but the dry sump tend to make more power because it is pulling vac.... were the conditions the same as you dynoed last time.. remember that the number you get is for the conditions that day(even on the same dyno) 
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Re: Horsepower loss with Dry Sump??
[Re: Mpetros]
#1441298
05/24/13 11:22 AM
05/24/13 11:22 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Conditions where about the same.. Maybe 5deg cooler Yesterday from last Year 
Temp is only one aspect... was the humidity up...
pretty hard to burn water(the outside air coming in)...
but its hard to say where you lost 24 hp... even with
the added vac(which I wouldnt run 20"... too high and
can draw the oil off the wrist pins) the pump is
still pumping the same pressure ... unless you turned
up then it would require more power to turn the pump
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Re: Horsepower loss with Dry Sump??
[Re: Mpetros]
#1441302
05/24/13 11:32 AM
05/24/13 11:32 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
I had 60 psi with wet sump at 7800..
I now have 85 psi now with dry sump
The higher pressure will suck a bit more power(greater
back pressure)... so now you have changed the test
parameters and I would expect different results
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Re: Horsepower loss with Dry Sump??
[Re: Mpetros]
#1441304
05/24/13 11:55 AM
05/24/13 11:55 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
So do You think 24 is about right for the pressure change?
Just wanted to make sure I wasn't missing something 
Your asking something that is a unknown.. with your
engine it MIGHT be, but like normal... all engines are
different.... I dont have a curve/graph to say what
power it takes to turn the pump with different pressure
points... I set my dry sump so I have 75 pounds at
rev and change the oil viscosity to keep the hot idle
pressure to what I want
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Re: Horsepower loss with Dry Sump??
[Re: fishy340]
#1441306
05/24/13 12:51 PM
05/24/13 12:51 PM
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Joined: Jan 2003
Posts: 19,384
Las Vegas
Al_Alguire
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 19,384
Las Vegas
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Yeah somethig sounds a little odd. I would not necessarily expect more power form a dry sump over a good wet sump but I see no reason for it to loose that much either.
Who's pump is it? Also I think that is probably a lot more oil pressure than you need and the extra pressure will cost a few HP.
Lastly as MrP points out weather can have a huge affect on HP numbers. Temp is actually the variable that will affect it least. Humidity, and barometric pressure will have a larger affect. Where these corrected or uncorrected numbers?
"I am not ashamed to confess I am ignorant of what I do not know."
"It's never wrong to do the right thing"
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Re: Horsepower loss with Dry Sump??
[Re: Mpetros]
#1441307
05/24/13 05:54 PM
05/24/13 05:54 PM
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Joined: Jul 2010
Posts: 2,091
Delray beach, Florida
Performance Only
top fuel
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top fuel
Joined: Jul 2010
Posts: 2,091
Delray beach, Florida
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I'd get that vacuum setting under control first. as mentioned, 20" of vacuum is too much.
You said you freshened the engine, but there are a lot of unknowns about that part of it.
It could be as simple as not having the rings seated fully yet. I've never seen a dry sump engine make less horsepower because of the pump.
What are the bsfc and bmep numbers from before and now?
machine shop owner and engine builder
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Re: Horsepower loss with Dry Sump??
[Re: ahy]
#1441310
05/25/13 09:24 AM
05/25/13 09:24 AM
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Joined: Nov 2004
Posts: 4,330
Lynchburg, VA
Leon441
master
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master
Joined: Nov 2004
Posts: 4,330
Lynchburg, VA
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20" vacuum too much? Really?
At what RPM.
When I had my W8 at BES we could not get but 12". They found some leaks and got it up to 20" with a wetsump. That is what they wanted.
How much oil pressure do you have at idle? You only need around 20 psi. So you can change you pulley to slow the pump down. Also 50 psi is really all you need at full boogy. There is a regulator on the rear of the pump to adjust pressure. But, slowing the pump down is the first step if you have plenty of pressure at hot idle.
Leon
Career best 8.02 @ 169 at 3050# and 10" tires small block power.
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Re: Horsepower loss with Dry Sump??
[Re: Leon441]
#1441311
05/25/13 09:40 AM
05/25/13 09:40 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
20" vacuum too much? Really?
At what RPM.
When I had my W8 at BES we could not get but 12". They found some leaks and got it up to 20" with a wetsump. That is what they wanted.
How much oil pressure do you have at idle? You only need around 20 psi. So you can change you pulley to slow the pump down. Also 50 psi is really all you need at full boogy. There is a regulator on the rear of the pump to adjust pressure. But, slowing the pump down is the first step if you have plenty of pressure at hot idle.
Leon
According to Reier/Morrison(sp) they did testing and
seen that above 14"hg that it could cause problems
and waste power to go higher... yes higher vac does
help seal the rings better but that was all... it would
start pulling oil off the pins at the higher points
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Re: Horsepower loss with Dry Sump??
[Re: Leon441]
#1441312
05/25/13 11:04 AM
05/25/13 11:04 AM
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Joined: Jan 2003
Posts: 7,498
Minnesota
Hemi_Joel
master
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master
Joined: Jan 2003
Posts: 7,498
Minnesota
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Quote:
...Also 50 psi is really all you need at full boogy. There is a regulator on the rear of the pump to adjust pressure. But, slowing the pump down is the first step if you have plenty of pressure at hot idle.
Leon
Joe mondello (rip) always said that you need 10 psi per 1000 RPM, to overcome centrifugal force. Has that changed? I sure would want more than 50 psi at 7800 rpm. 
[img]http://i.imgur.com/boeexFms.jpg[/img]31 Plymouth Coupe, 392 Hemi, T56 magnum RS23J71 RS27J77 RP23J71 RO23J71 WM21J8A I don't regret the things I've done. I only regret the things I didn't do. "Wise men talk because they have something to say; fools because they have to say something. ~ Plato"
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Re: Horsepower loss with Dry Sump??
[Re: Hemi_Joel]
#1441313
05/25/13 11:17 AM
05/25/13 11:17 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Quote:
...Also 50 psi is really all you need at full boogy. There is a regulator on the rear of the pump to adjust pressure. But, slowing the pump down is the first step if you have plenty of pressure at hot idle.
Leon
Joe mondello (rip) always said that you need 10 psi per 1000 RPM, to overcome centrifugal force. Has that changed? I sure would want more than 50 psi at 7800 rpm.
You really dont need the 10psi per 1000 revs in the
upper RPM.. remember pressure is a by-product of flow
vs restriction ... if you have good flow its getting
lubed... alot of guys run above 7000 rpm with 70si max
and some even run as high as 9000 with that same 70psi
but that 10 per 1000 was a standard number for YEARS
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Re: Horsepower loss with Dry Sump??
[Re: MR_P_BODY]
#1441314
05/25/13 02:21 PM
05/25/13 02:21 PM
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Joined: Nov 2004
Posts: 4,330
Lynchburg, VA
Leon441
master
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master
Joined: Nov 2004
Posts: 4,330
Lynchburg, VA
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Been sharing notes with a guy who worked at Arringtons shop where they built engines for Craftsman truck. They turn 9,700 with only 50 psi and ran 15" of vacuum. Some teams would seal every bolt and thread to get 17" but saw no power.
I ran 20" and never had any pin wear problems that would suggest lubrication issues. But, I would assume I was running a smaller pins and piston bore than what Reher Morrison was testing with.
My newest project has forced oiling to the pin through the rod. But, if your oil control ring and piston are working properly you should have plenty of oil at the wrist pin no matter what the crankcase vaccuum. Just my opinion.
Leon
Career best 8.02 @ 169 at 3050# and 10" tires small block power.
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