I finally received most of my goodies from LET a few days ago and finally to to install the LET heat exchanger and Johnson water pump. I took a bunch of pics so you guys can see the before/after and differences between stock and aftermarket. The install was pretty straightforward but I did run into a couple snags that I had to take care of.


Before pic of stock HE and water pump
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Comparison between stock HE and LET HE
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I decided to reuse and modify the mount bracket for the stock water pump. First; after removing stock pump, I ground down the little "humps" to make the mount surface flat.


Then I bolted the mount for the Johnson pump on and set it on the stock bracet to see where/ how it needed to be mounted. After measuring I welded on two studs and painted it all black again for the "stock" look.


After that I just bolted the Johnson pump on the stock bracket and bolted it onto the car. I also had to modify the wiring a little and cut off the original plug in and replaced it with bullet type connectors and wrapped all the new wiring in OEM style electrical tape
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Here's the finished product
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There were only two things that I'm not fond of with the new HE.
1) there's no mount/support on the bottom of the HE and it can be moved/twisted back and forth.
2) you can no longer use the stock air guide that filled the space between the bumper and HE.



Ohhh, and I ended up having to switch to worm gear type clamps on the Johnson pump as it is a slightly smaller OD than the stock pump. I found that out after I filled the water/coolant and it started leaking like crazy all over my floor.

 

Nice install - Looks like a huge improvement over the stock setup..

Couple of questions

Did you modify/drill the lower grills to improve airflow around that big HE?

Do you think there is enough room by the pump for a small recovery tank for the Intercooler?

I found a remote filler neck that could be used to feed a small remote mounted tank.

http://www.cantonracingproducts.com/...olant_acc.html

Thanks for the great picks!

BTW - Love that SL55 Intake shot

 

I had already taken my pencil grinder to all the holes that "should" have been cut out from the factory before the HE was ever made. It just happened to be the same amount necessary for the LET HE.

There is a decent amount of room near the water pump if you were to fabb up a custom triangular tank/resevoir.

 

How difficult is it to remove the front bumper and how exactly do you remove it?

 

I work on M-B cars every day so it was super easy for me..............took 10 minutes using hand tools.

To make things nice and easy it's best to jack up the vehicle first and put it on stands. Then you can remove the two(one on each side) torx T20 bolts on the edge of the bumper inside the wheel well holding on the fender liner. With those out you can open up the fender liner and have access to the 10mm bolt and 10mm nut holding the bumper to fender on each side. While in there you can easily unplug the sidemarker lights by a simple 1/4 turn of the socket. Then there's 3(one on each bottem corner and one in the center) two piece "rivets" that hold the fender liner bottom edge and main splash shield in place. After those are out you can remove the front lower bumper grilles by simply pulling on them with your fingers or a small hook tool. Once those are off you need a short 10mm socket and ratchet to access the 2 10mm nuts that bolt on backwards through the bumper into brackets on the car. You will not be able to see the nuts and must remove them by feel. Once they are off you can remove the 2 torx T30 bolts on the top edge of the bumper near the headlights and the 4 8mm bolts holding the big front grille on. Once all that is done you can pull the bumper off the car about 6 inches and disconnect both foglight assys. and the ambient temperature sensor......................and you're done. Simple as that. LOL

 

Doesn't sound too bad at all!

 

I don't see anything but red X's for pic's, but I've had the front bumper off so I know whats in there. Your #2 dis-like don't sound good, that's what really funnel's the air to the HE, do you have plans to fab up something to take it's place?

 

Yeah; I'll eventually make my own little air guide to "force" the air through the HE. It still gets plenty of air.


Before I changed the HE, thermostat and water pump the cars temp was always rite in the middle if not a little past and since the install of those parts it seems to stay between 1/3 and a little below 1/2 mark. Definately stays cooler which is exactly what I was hoping for.

 

Mopar,

I did all three like you did. My car runs the same temps you are running but if I run it a little harder, the temps will rise to the half way mark and it has a hard time lowing it on it's own back down to the 1/3rd mark. Does yours do that?

Steve

 

May I suggest FANS. But they probably would fit behind the larger HE.

 

Mine hasn't ever made it back up to the exact 1/2 mark yet..................maybe I'm not driving it hard enough.

 

I like the custom air guide you made in the picture.

 

Steve,

With the new HE, there is no room for a fan. It is strange. If I drive what I would consider normal, the temps don't go above 1/3rd. All is great. If I get on it a few times, it seems to run up to a needles width below 1/2 and will stay there until I shut it off and drive again.

I like the idea of drilling more holes in the lower grills. Good idea. This may be the ticket. My car is so much more responsive but then again, I was driving around with a pump that did not work properly without even knowing it ever since I had the car.

Steve

 

Originally Posted by Steve Hellums

Actually I think you get more air through the two openings below the lower grills where there is a plastic rectangular guide that fits under the openings.




I had taped that peice of paper out on the end of the tape measure a little over 7" away and turned the fans on just to see if the fan would pull it to the HE. At that distance I thought it was quite impressive.

 

Playing around with the IAT gauge I installed - I discovered that the IAT's climb very rapidly when:

1) the SRT is stopped (or in stop & go traffic) - no air flow around the HE
2) when boosting heavy
3) the SRT is parked with the engine off (this is when heat soak really kills you)

During normal driving the IAT' are actually pretty tame. Once you boost hard the IAT's rise very quickly and once you back off and keep the SRT moving - the IAT's will come back down - but slowly. I have parked the SRT with the IAT gauge reading 99deg - go have lunch - return and when I start the SRT - the temps are up to 135deg and will take a while with the SRT moving briskly to come back down.

For the 1/4 mile enthusiast
1) will be staging
2) will be the 1/4 mile run
3) will be when you are parked waiting for your next run.

I think Steve HE fans are going to be a big help - or else you will need a seperate HE recovery tank that the coolant must flow through (not draw on like our stock tanks) - then you can drop Dry Ice into the coolant prior to your run and help tame those IAT's.

I know this isn't new info - Just something I confirmed with an accurate IAT prope and gauge.

 

Although you are measuring air temps & I'm measuring coolant temps, I've noticed the exact same thing. Just crusing town they stay low, but the minute you start getting into it the temps rise fast. I was suprized how fast they dropped though once you start heading down the highway at normal speeds.

 

Hey Brian, have you done any testing of what kind of voltage is being delievered to the pump from the pump control module at different RPM's? The "pulse voltage" has got me a little confused, I just wouldn't have thought the pump motor would be variable speed, but I'm thinking it is. I just havn't dug into it that far yet.

 

I haven't had the bumper off yet. I tapped for the IAT probe next to the boost gauge location.

I just received the CM30 Johnson pump today from LET and the pump manual doesn't mention about different pump modes/cycles. Just flow rate at different head distances.

I'm going to try something different with the HE - it might just work but I am still not sure (if not I will buy LET's HE - that thing is HUGE!!) - but it still won't be the optimum 1/4 mile setup (your MOD is perfect for the 1/4 mile) - I only plan on tracking once or twice out of personal curiosity to see what kind of beast I have built. I also have some additional heat reduction mods in store - I will post them and the measured results when I am done.

I'm itchin' to rip the bumper off tonight and get started - but I have a friend flying in tomorrow and I am going to pick her up at the AP - she wants to see my SRT so the mods will have to wait for the weekend..