HOW TO DO AN ADVANCED SEARCH.

Mon Jul 08, 2013 3:56 pm by Admin


For the benefit of 944Hybrids users there are two search functions available for you to use.
The purpose of this sticky is to explain the "Advanced Search" function because it is much more powerful and is the best choice when researching information.

When you log on to the site a list of options is shown in a line at the top of the page. One option is labelled "Search", use this option (NOT the search box lower down on the right).

After you click on the upper search option, a drop down box appears. At the bottom of this box is a radio button marked "Advanced …

Comments: 0

Latest topics
» 1986 Porsche 944 NA LS1 swap start
Yesterday at 9:37 am by vapistol

» WHERE to put ECM?
Yesterday at 9:23 am by vapistol

» Early offset phone dial
Thu Oct 19, 2017 10:45 am by GarethW

» 1987 944 Turbo --> LS
Wed Oct 18, 2017 9:25 am by chrenan

» Oil Cooler Adapter Not Working?
Wed Oct 11, 2017 9:32 pm by sharkey

» 1987 944S 3800 L67 Turbo...in progress
Wed Oct 11, 2017 1:08 pm by Sirayden

» C6 Z06 Brakes on my 944
Wed Oct 11, 2017 8:25 am by Schuepbach

» sbc swap in a 1981 924
Mon Oct 09, 2017 9:28 pm by sharkey

» JP's LS1 Conversion
Mon Oct 09, 2017 8:42 pm by 924sbc406

» Cayenne Front and Rear Brakes on 944
Sun Oct 08, 2017 4:15 pm by superman22x

October 2017
MonTueWedThuFriSatSun
      1
2345678
9101112131415
16171819202122
23242526272829
3031     

Calendar Calendar

Log in

I forgot my password


LS1 reverse cooling

View previous topic View next topic Go down

LS1 reverse cooling

Post  xschop on Mon Dec 28, 2009 9:26 am

Anyone seen this....
[You must be registered and logged in to see this link.]

Found it while looking for a flow diagram for the LS1 vette pump if anyone knows of a flow diagram out there.
avatar
xschop

Posts : 2710
Join date : 2009-06-09
Location : OKC

Back to top Go down

Flow diagram

Post  xschop on Wed Jan 13, 2010 7:04 pm

Anyone have a drawing/flow chart of the LS1 water pump?
From the old truck pump I have I can't tell which way the water flows and exits. I am not sure if I can just run without a Thermostat without messing up the flow ports to the heater or not. I thought someone posted that the larger port on the pump comes from the heater core return?

I may have to make an inner block-off plate, I'm not sure of it as of now....
avatar
xschop

Posts : 2710
Join date : 2009-06-09
Location : OKC

Back to top Go down

Re: LS1 reverse cooling

Post  Porch on Wed Jan 13, 2010 8:34 pm

(edit): I'm sure it would benefit from reverse cooling, but i doubt enough to justify the hassles. Only one way to find out! Very Happy
avatar
Porch

Posts : 851
Join date : 2009-09-02
Age : 36

Back to top Go down

X-post

Post  xschop on Thu Jan 14, 2010 10:15 am

I posted the question in the tech section over on LS1.com
I am really only interested in making sure my heater will work if I completely remove the T-stat from the pump or if I need to put in a block-off plate on the inside somehow between the two heater ports... But it is interesting that a reverse vein propeller could be installed into the pump housing to make the water flow in the opposite direction... Would this be a simple solution for Reverse cooling? The guys over there still haven't stated concretely if the heads or block is cooled first on these motors....
avatar
xschop

Posts : 2710
Join date : 2009-06-09
Location : OKC

Back to top Go down

Re: LS1 reverse cooling

Post  944-LT1 on Thu Jan 14, 2010 11:34 am

The coolant enters through the lower right hose, into the tstat housing, past the tstat when at operating temperature and into the block and surrounds the cylinder bores. Then, it goes up through the head gasket and into the head. After cooling the heads, the coolant then goes back to the pump and through the upper radiator hose and into the radiator. So in short, the coolant goes UP in the engine and down in the radiator.

The reason for reverse cooling was antidetonation for the high compression LT1 engines and for heating the oil of the resulting hotter cylinder bores for less friction. This was simply a fix by GM for the hotter running LT engines due to high compression. The biggest problem was that the coolant was flowing down throughout the engine and air/steam was flowing ofcourse up causing hot spots along the cylinder bores and thus....detonation and keeping the system completely airless was very difficult.

but, the LS1 has lower compression and really well designed combustion chambers/heads as well as a severly reworked block including the water jackets.... so they scrapped the reverse cooling for the small block due to these changes...no need.

_________________
[You must be registered and logged in to see this image.]

[You must be registered and logged in to see this link.]
avatar
944-LT1
Moderator
Moderator

Posts : 1251
Join date : 2009-06-09
Age : 95
Location : NOTRE DAME

Back to top Go down

Re: LS1 reverse cooling

Post  Dawgz83948 on Thu Jan 14, 2010 12:06 pm

....and they lost a law suit.....http://www.autoblog.com/2006/06/13/inventor-may-win-big-in-suit-against-gm/
avatar
Dawgz83948

Posts : 601
Join date : 2009-06-08
Location : Ca.

Back to top Go down

Re: LS1 reverse cooling

Post  Porch on Thu Jan 14, 2010 2:29 pm

LOL, didn't know they finally lost that lawsuit. I read up on it a while ago and it was some total BS that they pulled.

The point of reverse cooling being that you could run a few more degrees of timing by cooling the cylinder heads first with cooler coolant.

And on that note...when is one of you going to give up on these "5hp here, 5hp there..." ideas and just slap a damn turbo on the car? It would simplify exhaust routing drastically, and there is room (i've considered it!). For all the hours spent looking at equal length crossover header designs, reverse cooling, etc....you would make a ton more power and get a lot more props with a simple turbo setup!!
avatar
Porch

Posts : 851
Join date : 2009-09-02
Age : 36

Back to top Go down

reversed c

Post  xschop on Thu Jan 14, 2010 3:12 pm

I am only looking to do a mod to the LS water pump and remove the thermostat. On the last V8 swap I did to a 2.8l S-10, all I did was remove the T-stat and did not change to a larger radiator. All my overheating issues went away. In the winter, I just reinstalled the T-stat and the heater blew nice n hot and engine never overheated. My theory is the stock 944 NA radiator with the T-stat removed would be the best cooling set-up and obviously the easiest. The inner port hole between the heater ports on the LS1 pump can be blocked off. I have read elswhere that a 1/2" hole is drilled in a freeze plug and installed. I also see that the 160deg T-stats have 4 small holes drilled in that block-off plate. The only reason I can see why GM put that small rear block-off plate(spring loaded) was in case the radiator (even heater core) were to be clogged, the coolant would just recirculate within the block. Looking at the Truck Pump, the inner port hole could be enirely blocked off with an epoxy'ed freeze plug or the stock T-stat could simply have the upper piston drilled/removed and the heater would function normally and the water velocity would remain constant and increase with RPMs.
avatar
xschop

Posts : 2710
Join date : 2009-06-09
Location : OKC

Back to top Go down

Re: LS1 reverse cooling

Post  xschop on Thu Jan 14, 2010 8:40 pm

I removed the back cover from the truck WP to double check the flow route of this pump which should be exactly the same as all the LS pump routings. From what I see, if that inner port hole is blocked off completely and the T-stat removed the coolant velocity would be higher going to the top radiator and cool much better.
avatar
xschop

Posts : 2710
Join date : 2009-06-09
Location : OKC

Back to top Go down

Re: LS1 reverse cooling

Post  944-LT1 on Thu Jan 14, 2010 8:42 pm

I didnt think people were having cooling problems with the LS series engines. I am new to the LS engines so is this whats happening? The LT was a PITA to cool so I was hoping the LS was a much cooler running engine.

_________________
[You must be registered and logged in to see this image.]

[You must be registered and logged in to see this link.]
avatar
944-LT1
Moderator
Moderator

Posts : 1251
Join date : 2009-06-09
Age : 95
Location : NOTRE DAME

Back to top Go down

Re: LS1 reverse cooling

Post  Porch on Fri Jan 15, 2010 4:28 pm

No, no cooling issues with the LS motors. He's strictly talking for performance gains, i believe.
avatar
Porch

Posts : 851
Join date : 2009-09-02
Age : 36

Back to top Go down

Re: LS1 reverse cooling

Post  xschop on Fri Jan 15, 2010 4:55 pm

The whole point is leaving the NA radiator and fans untouched....I bought the rear steam block off kit for the LS1 which is perfect for the LS1 intake that I installed on the truck motor.....Now Where does the front steam tube go to on the 944 radiator/overflow tank then?
avatar
xschop

Posts : 2710
Join date : 2009-06-09
Location : OKC

Back to top Go down

Re: LS1 reverse cooling

Post  Porch on Fri Jan 15, 2010 9:04 pm

I just "T"d mine in to the bleeder hose coming out of the top driver side of the radiator and going in to the overflow tank.
avatar
Porch

Posts : 851
Join date : 2009-09-02
Age : 36

Back to top Go down

Re: LS1 reverse cooling

Post  xschop on Fri Jan 15, 2010 10:29 pm

Thanks Porch. Wasn't sure about that detail. Also I assume the smaller dia. heater core tube on the firewall is the influent to the core and large dia. is the return back to the water pump?
avatar
xschop

Posts : 2710
Join date : 2009-06-09
Location : OKC

Back to top Go down

Re: LS1 reverse cooling

Post  Porch on Sat Jan 16, 2010 11:09 am

I'll go take a look in a bit, but if memory serves me correctly i just ran the 5/8" outlet from the water pump in to the 5/8" inlet on the heater box, and same with the 3/4". I did a write-up on it on PHB a while ago, i wonder if it made it into the manual? I need to order those one of these days once my car stops eating money :/
avatar
Porch

Posts : 851
Join date : 2009-09-02
Age : 36

Back to top Go down

View previous topic View next topic Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum