Intercooler pipe thread

Does anyone know the thread pitch/diameter for the collar the screws onto the intercooler tubes and the one for the top hat nut?

I am fabricating new longer tubes to use with the stock Intercooler in its new location and if I can have steel bushings made with the proper "nut thread" than I can weld them to the new steel IC tubes and use the SC nuts and flanges.

See the photos below.

As always, all input is appreciated.

Doug

Most folks just take the collar off and use contant torque clamps to hold some sort of composite hose on there.

My goal is to adapt as many of the SC parts

as possible and because this chassis/engine compartment is very tight, I need to keep everything as compact as possible so adding an adaptor between the IC and the tube is not my first choice.

I suppose, if all else fails, I could have a short (2") nipple (or elbow) welded to the intercooler and then use your (Mike) hose/clamp suggestion.

Doug

i would go to a better i/c if i were going to all the trouble you are in moving it. ebay has many of them for fairly cheap and they'll flow much more air than a stock hunk of junk.

look for one with both of the outlets on one side and the piping would take up less room than the configuration you show in your pics.

OEM vs aftermarket IC.

I agree .... sort of. It could make economic sense to buy one as you suggest, if the cost of nipples or elbows and welding approaches the cost of an aftermarket unit.

Regrading performance potental, I am under the assumption that the OEM IC (if cooled properly) can handle the airflow requirements of mildly modified engines. Highly modified engines are a different story.

Your thoughts?

The stock IC has two issues.
#1 - it doesn't have sufficient surface area to cool the amount of hot air the M90 can create.
#2 - It's design creates a significant pressure drop between the inlet and the outlet.

#2 is still there if you fix #1.

Those thread sizes are likely US Pipe. Take the tubes to a hardware store and check the galvanized pipe section for a coupler that'll fit. Then you'll have your size.

nothing wrong with saving money but all i'm saying is you're looking at very minimal gains at best.you have an excellent idea but for $200-$250 you could buy a better i/c and piping kit than would give you significant gains in cooling capacity and hp. i'm in the process of fabbing up a front mount i/c on a 89sc with ac delete.i bought everything off of ebay for $250.the i/c floes 1200 cfm compared to a stock which flows about 270 cfm.

I've had a machinest measure the thread,

Great input, tks.

The thread is not a pipe thread It is a straight machine thread and it measures somewhere between 16 and 17 threads per inch thats why I believe it is metric. Also, it seems everything else on my car (donar) was metric.

You mentioned pressure drop accross the coil, knowing what that is (approximately) would help me shop for a new IC.
do you have an idea what that might be?

I can't find an old thread that had the info from someone testing it. Keep in mind that there is some pressure drop simply from cooling the air. Cooling the air causes the components to fit closer together, which mean they won't take up as much space, thus pressure drops.

But another part of it is the restriction from having to push the air through the core. That's the part you want to limit. There is alwasy going to be some pessure drop due to having push air through a core so it's surface can rub up against the cooling pipes and such in the core. What the stock SC unit does is have end tanks that really force the air in and out of the core in a way hurts air flow. It also creates an issue how the air flows through the core.

Now in general, it's main issue is it's ability to cool the air is limited, especially if you're looking at a bunch of WOT runs. It did o.k. for a showroom stock car driving a little fast to get groceries from time to time, or run a hot lap for a car mag. But if you want to be still gaining speed at the end of a 1/4mile run, our stock SC just won't be the type of unit you want to have. Of course options are limited.

Tbird88

nickleman60 said:

look for one with both of the outlets on one side and the piping would take up less room than the configuration you show in your pics.

Click to expand...

Both Outlets? I hope that you mispoke yourself, & you're talking about the inlet & outlet being on the same END of the IC. Wynn (Tbird88) builds those type of IC's.

68COUGAR

you can call them either and i've seen wynns but his is a stock double i/c with the inlet/outlet on the top.i'm talking about a front mount i/c with the inlet/outlet on the same end.

Here is a picture of my FMIC when I was building it. Inlet and outlet are on the same side. Mine is made of two stock ICs with fabricated end tanks to eliminate to poor design of the stock end tanks. Even a dbl IC such as most of the guys on this site build will not flow good if they use the stock end tanks. Mike is right on when he saids the stock IC doesnt flow well and the end tanks are a big reason.

Ken

ken that's a good looking setup,you ought to see some gains with that

Ok .... I'm leaning ever so slilghtly toward a new IC.

Any thoughts about the Grand National IC shown on ebay and sold by ?

I found the pressure drop article had seen right here off the index page http://www.sccoa.com/articles written by Charles Warner. Not only does it talk about the pressure drop but also shows measurements he made after changes.

Good reading.

nickleman60 said:

ken that's a good looking setup,you ought to see some gains with that

Click to expand...

My mistake was not running it on the dyno before I installed it. On the dyno after installation it only hit 85 degrees at its highest reading. I recently added the menthol injection and saw a high of 74 degrees during dyno runs. I beleive the stock end tanks are what kill the stock IC. With good end tanks the cores do a good job of cooling the air. I dont think a single stock core will flow enough air for a modded SC to be benificial. There are a lot of IC on E bay that flow better. Just be sure you can fit it in the alloted space. My 2 cents

Ken