Once you start putting more duct/hose and bends you are adding restrictions to the air flow. I already have a w/m injection system but what many may not know is that the injection can actually cut horsepower while it is cooling the intake air. The question I need to research is whether the GP IC is thicker than the S or only merely taller/wider.

 

Here is a picture of the OEM S and GP ICs. The OEM S is 2" thick and I am thinking the GP is the same. If you enlarge the picture it appears you can see where the factory merely welded an extension on the horn connection and added 2 more rows of tube/fins. I am thinking you don't even need to buy the ebay unit but rather piece two OEM S units together. I would think I could plastic weld two covers together as well.

I may have just found another project to keep me busy while the Mountain Twisites are sanded/salted until spring.

 

If you are not building an all out race car that's going to see most of it's life on the track, a GP (or any larger) IC is just going to soak up heat more in stock and go daily driving. I've newer really heard of anyone seeing real power benefits from them in a real world, daily driver situation.....if anything, they heat soak WORSE than the stock S intercoolers.

 

I just bought two OEM S IC for a total of $72 that includes shipping. Will see where this goes.

I am putting on a TPR2 head and currently have a 19% pulley ratio but as the redline will be increased to around 7250, so going to drop down to a 17% ratio. A DIY GP IC should help with the intake cooling. The GP duct is a different part number but the Hood is the same. It appears that I can modify the foam tape that seals the duct to the intercooler.

 

BUT.....is this going to be a track car, or a street car? If street......then it's going to soak up a lot more heat. You are better off with a stock S cooler, and a larger M7 hood scoop. That way at slow speeds, you are not heat soaking like you would with a larger IC...but at faster speeds, you are pulling more air through the IC....cooling the intake charge more. Kind of the best of both worlds....

 

I do not track or AX and I don't do any daily driving so I am thinking that two more tubes/fins are not going to produce excessive heat gain. I would think somebody has either thought of this before and actually performed the work. I would make a jig up with plywood so I can get the thing together while I am working on it and then can use the jig to make up some extension tabs for the screws on the engine/top side. They make special circular saw blades to cut aluminum and think I can cut the units on my table saw or will make a jig to use a circular saw. This should give me some good square cuts to work with. Some weatherproof heat sink paste/grease would be spread where the fins meet the tube. As the tube/fins are already welded/connected into the side sections I am thinking the right side would be a simple butt attachment where the left side I would try to ease the larger section open a little so the smaller section with the two tubes would fit inside of it. The jig would be held via straps/pieces that are interior to the two ends so that the unit is help in place while the JB Weld sets up. I would have some 1/2" aluminum flat stock pop riveted between the two sections to help keep it together once it is on the car.

I would do something similar with the top trim. Would buy two used covers, cut them on the table saw and then plastic weld them back together on the bottom side. Use some fiberglass to fill in the cut on the front, sand it and paint it. Would get a vinyl diecut that simulates the GP emblem or come up with my own design.

A ThumpR IC to go with my Thumper TRP2 head.

 

I didn't see anywhere where you mentioned welding......I'm hoping you aren't going to JB weld it together....are you? Why not just buy one of the eBay or Amazon aftermarket larger IC's? They are like $80......that might be a better idea vs hacking up a couple stock IC's and glueing them together.

And yes....people have thought of, and tried the larger IC's before.....and they didn't see any gains. The stock S IC's are tough to beat for a street driven car.

 

I am thinking that I am going to need to make up some "plugs" that are pieces of aluminum to fit in the gaps between the tubes on either end.They would have to be JB Welded in place as I do not think you could get into the area and either braze or tig weld. If I have to go the JB weld plug connection than I would not want to braze/weld the other pieces as the heat would melt the JB Weld. This is where the 1/2" flat stock comes into play that would be pop riveted.

I would rather spend $90 on trying to make this work then buy an ebay unit that has no upper mount holes and may have incorrect size/shaped horn rims. If it works, the NAM membership is helped, if it does not, than I am out the money but the failed effort does give this retired old fart something to do.

Also, the GP IC Cover does not have a larger opening than the OEM S cover so in other words the OEM Duct on my JCW will work. I can remove the JCW emblem off my silver cover and just stick it to the cover that I make up. I get done and allot of people will not be able to tell the difference.

 

I read this thread over and over and I just had to try it out myself. I went and bought one of these cheap eBay intercoolers. It did not fit my R53 I also bought some silicone boots that did not fit either (too small to fit on the horns). The opening from the intercooler is just too thick compared to the OEM intercooler which will restrict airflow. It was a tight fit with even the stock boots. I just decided to put the OEM back on. I don't know if I should go and buy an MTC intercooler but it's like 260 bucks with tax and shipping, which is almost 3 times this one cost. You guys said that it's better to keep the stock one so I might just do that instead. Both the eBay intercooler and the boots did not fit and wasn't worth the time or money.

In from supercharger

Out to intake manafold


s which also did not fit.

 

Here are the measurements of the eBay intercooler. Sorry if the measuring tape is not straight I was in a rush since I had to get to work and I wanted to do this before I can't return it.

 

AGAIN...

IF you know anything about airflow, you'll stay away from these coolers ! Note the shape of an airplane leading edge !!!
With the photos above, it REALLY easy to see why. Note the flow directors between the inner tubes in the OEM cooler. Note the "flat", non-streamlined tube in the aftermarket cooler. Plus, the very thick inlet wall.
ALL BAD for flow. The higher the flow speed, the worse it is for good flow.

Do you REALLY think that the factory would have gone to the expense of adding the flow directors if it wasn't worth anything ??? Personally, I'd stay away lit it was laden with the black plague.

Mike

 

Even the Forge Intercooler doesn't have the flow directors and that's a 600-dollar intercooler. Yet people buy those intercoolers and put them in their minis. So comparing the Forge intercooler to this eBay intercooler they don't have many differences besides build quality. Both eBay and the Forge don't have flow directors. So what is the need to spend 5 times more for the forge intercooler? The R53 and the GP1 intercooler have the flow directors, I could not see if the MTC intercooler had the flow directors. UPDATE: Even the GRS intercooler doesn't have the flow directors with the pictures I saw online.

 

From what I have seen and read over the years about intercoolers for our cars:

Best - GP unit
Second best - stock unit found on the R53'S and the R52 S cars.

Everything else, stay away from. The engineers that designed the stock IC unit knew what they were doing and it's been proven over and over again that the stock one is best for all around usage. The only one better is the GP unit if you can afford the stoopid money they are asking for that one

Bryan

 

Thank you for the clarification, I will go ahead and do a refund for the eBay intercooler. So the stock IC is good enough for 17 or 19% pulley reduction?

 

I'm running a 17% pulley on my R52 JCW car and stock intercooler... haven't had any issues.

The 19% pulley might be pushing the stock IC to it's limit... so maybe think about the GP unit next if you can find and afford it. Personally, I wouldn't go past the 17% pulley...my opinion of course

Bryan

 

Alright thank you, I got a 15% right now so I just do my research if it's worth the 17%. Thanks!

 

I loved the 15% pulley that was on my R53 when I had it... really woke the car up.

I have the 17% pulley on my R52 JCW car now, I really haven't had the time to put it through the paces to feel any difference. The R52 is a heavier car... so my test might be affected by that.

Bryan

 

true that.

There's a Forge unit up on the 'bay right now with good pictures,
will add them here for reference: