Saleen S/C's and High Air Inlet Temps

[tmcolegr]

A little background: I have been working on and installing Saleen S/Cs on our S197s since they first came out several years ago. I personally own 2 S197s with Saleen S/Cs. Today I discovered something that I probably should have realized a long time ago and thought I would share this epiphany.

Like most everyone else that has a Saleen S/C'd vehicle, I am running a smaller pulley than the supplied 4" (4 psi) pulley. My wife's vehicle has a 3.2" pulley and my vehicle, that has a built motor, runs a 2.75" pulley. I have always assumed the higher IATs were the direct result of higher boost levels and this is true but not the entire story. High IATs have always plagued these vehicles. On my vehicle I installed an Afco GT 500 Dual Pass Heat Exchanger and even installed twin Spal fans. Even with the larger heat exchanger and dual fans, IATs were higher than I would have liked to have seen. So the next most logical step was to install a larger reservoir. Prior to installing the reservoir I decided to take a very close look at the complete I/C system to find out why it wasn't efficient.

On to the the heart of my post. The Saleen S/C uses 3/4" hoses. The I/D of the inlet/outlet to both the I/C pump and stock Saleen heat exchanger (as well as the Afco unit I installed) is 5/8" in diameter. Today I decided to look at the stock Saleen reservoir. While it uses the same 3/4" hoses, the I/D of both the outlet and return passages are only 1/2". See attached photos

That 1/2" I/D is 25% smaller than all the rest of the hoses/fittings in the system. After seeing this, it is my personal belief that the I/C pump can not supply the rated GPM with this restriction and one of the first items that should be upgraded is the reservoir itself. Not necessarily just because of the qty of coolant it holds, but because the reservoir itself becomes a restriction in the I/C system by not allowing sufficient coolant to flow to the I/C pump, which affects the overall efficiency of the entire system.

For comparison the fittings that will be installed in my new Canton reservoir are 1/2" NPT x 3/4" hose and have an I/D of .625"

Note to all smart guys - feel free to comment on this thread even if it's nothing more than to say I am full of BS.

 

[RedMosesSC]

That Res is so rinky dink as compared the rest of the systems design.. Ive been wanting about swapping out my Stock Saleen IR but have not found a direct replacement, can you post a pic of your upgraded unit? Did you mount it in the same location?

 

[Barricade]

Awesome.....I am soooo in agreement and thanks for the post.
PLEASE keep us updated of your finding and what you use.

Im also running a 3.2" pulley.

 

[TexasKyle]

I can definitely see your logic, and agree that it's an issue. I am looking forward to seeing your IAT's after this mod.

 

[zipperhead]

My rant

Pump flow will always be restricted by the smallest opening anywhere in the loop. Elbows also can effect flow rate so keep these to a minimum.

I am not convinced that your IAT will come done by increasing the hose size unless your current flow rate is under what both heat exchangers were designed for and increasing the hose ID does indeed increase flow rate.

The intercooler pumps on these cars are open face impellers which are very sensitive to output restriction so you may be on to something

I would be curious if the super shaker IAT's are cooler than the other under hood intakes. IMHO under hood air is hurting your IAT's and I assume Saleen must have designed there system to compensate for this, hence the super shaker

 

[tmcolegr]

Just for shits and grins, I may borrow an in line flow meter from work and install it in the return line to the reservoir and measure the GPM of coolant returning to the reservoir with the stock Saleen reservoir. Then, since I am planning on replacing the stock Saleen reservoir with the larger Canton I/C reservoir anyway, I will enlarge the openings in the Saleen reservoir to the same 5/8" inside diameter as the rest of the system. If GPM increases, then the reservoir is definitely a restriction.

 

[tmcolegr]

can you post a pic of your upgraded unit? Did you mount it in the same location?

Don't have it yet. Custom unit from Canton. Battery box mounted.

My rant

Pump flow will always be restricted by the smallest opening anywhere in the loop. Elbows also can effect flow rate so keep these to a minimum.

I am not convinced that your IAT will come done by increasing the hose size unless your current flow rate is under what both heat exchangers were designed for and increasing the hose ID does indeed increase flow rate.

The intercooler pumps on these cars are open face impellers which are very sensitive to output restriction so you may be on to something

I would be curious if the super shaker IAT's are cooler than the other under hood intakes. IMHO under hood air is hurting your IAT's and I assume Saleen must have designed there system to compensate for this, hence the super shaker

Exactly!! That is my entire premise for the reservoir being a restriction. The reservoir may not be a restriction if boost levels were @ 4 psi as intended by Saleen. However, when boost levels are at 15 psi, I believe it can become an issue.

As you stated earlier IATs are the real test of the efficiency of the system. GPM of flow are only a contributing factor.

 

[shawn13]

Im running a 3in cowl hood with a steada H/E and my temps never went down at all.
Im not real sure if a diffrent reservor will make a diffrence or not, but would like see if it does.

 

[tbrock]

I installed an Canton Intercooler Resevoir for a GT500 on my Saleen SC'd car. I made a bracket for the powersteering resevoir and attached it to the valve cover on the drivers side. I do not have an IA temp gauge so I have no way to scientifically measure the difference, but my thought is the increased capacity alone should lower temps.

The other thing I did was to make my hood scoop functional on my SGT, which at speed has been shown to lower engine temps and the cool air flows right onto the SC'er lid.

 

[zipperhead]

Not sure how cold it is there, but If you can get away with it I would run all water with some water wetter.

 

[Back@itagain]

Im running a 3in cowl hood with a steada H/E and my temps never went down at all.
Im not real sure if a diffrent reservor will make a diffrence or not, but would like see if it does.

Ever thought of testing your underhood temps by closing that cowl opening? I have the same hood and am willing to bet the airflow in the engine bay is fighting itself now and not allowing the hot air to escape as well as before. That cowl should be pulling air in which could be interfering with the air moving through the radiator and downward...just a thought.

 

[shawn13]

I have thought of cosing it off some . I have the VFN hood and the whole thing is open. I trimmed up some cardboard as a template but aint made anything yet.

 

[fhlh]

subscribing...

 

[ChevyKiller]

You are not just 'on to something' - you are 100% correct. I have been there and done that awhile ago - not with a saleen specifically, but all the same and the bottom line is you have to look at the entire system as you are doing now.

The 'entire system' means just that. You also have to able to support increased flow in the IC itself which is the only factor where you might just be 'shit out of luck' with the saleen unit.

I found with the KB and whipple - increased flow and volume helped a little, but the real issue was the actual IC capabilities and I'd bet you are going to find the same for saleen sadly.

But great thinking though and way to attack the issue!...

BTW: When I finally 'perfected' cooling on my car, I see IAT's no more than 59º crossing the trap. The right IC application with the right flow combinations is what made all the difference in the world. Believe me, I tired every size resevoir, pump, etc - and they all had a little to do with it but the real meat and potatoes of you getting your IAT's low is in the actual IC.

When all said and done - it took this to see 55º IAT's at 160 mph crossing the line...

 

[kcobra]

I will tell you from seeing several intercoolers that they have a tendency to crack towards the firewall. I'm talking about the intercooler on top of the blower unit and under the inlet. Take yours off and look at it. They tend to crack at the welds and then hot air will be allowed in. The unit I took off my car had that and the used unit I replaced it with had the same problem. Have it welded and then the issue is fixed. I think this is one of the main caused of IAT's being out of whack. My temps are wayyyy lower than my tuner's car and we have the same exact set up.

 

[tmcolegr]

I will tell you from seeing several intercoolers that they have a tendency to crack towards the firewall. I'm talking about the intercooler on top of the blower unit and under the inlet. Take yours off and look at it. They tend to crack at the welds and then hot air will be allowed in. The unit I took off my car had that and the used unit I replaced it with had the same problem. Have it welded and then the issue is fixed. I think this is one of the main caused of IAT's being out of whack. My temps are wayyyy lower than my tuner's car and we have the same exact set up.

Appreciate the post but I just had the lid off of the S/C for porting. The I/C was fine.

 

[tmcolegr]

You are not just 'on to something' - you are 100% correct. I have been there and done that awhile ago - not with a saleen specifically, but all the same and the bottom line is you have to look at the entire system as you are doing now.

The 'entire system' means just that. You also have to able to support increased flow in the IC itself which is the only factor where you might just be 'shit out of luck' with the saleen unit.

I found with the KB and whipple - increased flow and volume helped a little, but the real issue was the actual IC capabilities and I'd bet you are going to find the same for saleen sadly.

But great thinking though and way to attack the issue!...

BTW: When I finally 'perfected' cooling on my car, I see IAT's no more than 59º crossing the trap. The right IC application with the right flow combinations is what made all the difference in the world. Believe me, I tired every size reservoir, pump, etc - and they all had a little to do with it but the real meat and potatoes of you getting your IAT's low is in the actual IC.

When all said and done - it took this to see 55º IAT's at 160 mph crossing the line...

I am curious what the sweet spot is for GPM of flow through the complete system. More is not always better. If the coolant flows too fast though the H/E and doesn't have enough dwell time, there won't be an efficient transfer of heat. Too slow and it will pick up too much heat from the I/C.

I believe you are absolutely correct in your statement that the I/C is the limiting factor for the Saleen S/C. No matter what you do, you can't change the size or efficiency of the I/C.

 

[tmcolegr]

Something else worth mentioning about using a larger dual pass H/E. Refer to this thread. If you're using a dual pass heat exchanger, that is not at least 200% larger in the core area, you're actually trying to push the same amount of coolant through less tubes as the single pass heat exchanger and creating a restriction to coolant flow. So although the heat exchanger is larger in physical size than the single pass heat exchanger, and has more overall height & width, the dual pass heat exchanger could be a part of the problem.

Fortunately the Afco H/E I used overall has a 206% larger core area (H x W x D), or is 103% larger per pass of coolant when compared with the stock Saleen heat exchanger, and is of the dual pass design.

 

[Back@itagain]

Something else worth mentioning about using a larger dual pass H/E. Refer to this thread. If you're using a dual pass heat exchanger, that is not at least 200% larger in the core area, you're actually trying to push the same amount of coolant through less tubes as the single pass heat exchanger and creating a restriction to coolant flow. So although the heat exchanger is larger in physical size than the single pass heat exchanger, and has more overall height & width, the dual pass heat exchanger could be a part of the problem.

Fortunately the Afco H/E I used overall has a 206% larger core area (H x W x D), or is 103% larger per pass of coolant when compared with the stock Saleen heat exchanger, and is of the dual pass design.

The Afco is not just dual pass but dual core also correct???. I did this same change from the Fluidyne that came with the Whipple which measure 10"x1.5"x21.1875" for a surface area of +/- 211.87". The Afco measured in a little shorter at 9"x2.5"x22.5" for a surface area of 202.85" obviously a little smaller. If yours is a dual core unit shouldn't the second row count as exposed surface area? So then why divide by 2? Why not multiple by 2 since you now, in essence, have the same surface area making a second pass for a total of 45" (22.5"x2) of exposure. Then this would come down to some physics forumal way past my education levels to determine how fast heat is transfered out of your medium (ie water, raditor fluid, etc) X amount of total time exposed/temperurate of outside air or some kind of thing? Not to mention the tanks on the Afco are larger which should still count but at a fractional level compared to the cores and fins.

 

[Zexford]

Major bottleneck