The SCCA rulebook for Improved Touring doesn't allow the splitter to extend backward past the front of the wheel opening.

I will be handling the shrouding of the radiator by attaching the shrouding to the radiator. The rulebook allows any radiator as long as no new holes are cut in the bodywork.

 

What size and brand radiator are you using? It looks like you changed to a cross flow, correct? Is it single or dual pass. What dementions fit best within the stock space? Im considering retrofitting a Griffin or the like GM style radiator as they seem pretty cost effective and the stock rad cant cut it. Sorry for thread jacking, I just love your setup.

 

The radiator is from Howe Racing, and if I recall correctly it's a 26x19 Chevy setup (top R - bottom L - single pass). I chose it because the core totally fills the opening in the radiator support, and it just fits inside the rail on the RT side. I don't know if it would work with a stock airbox or not, since I'm running a cone. For street use, you could probably go with a 24x19 which would allow more mounting options, and additional cooling isn't really necessary.

I recently installed an expansion tank setup, since my strut bar did not allow a radiator cap to be installed in the upper radiator hose. I'll have pics once it's completed.

 

Awesome, thanks!

 

My updated splitter pic below

I was racing this weekend and we ran the track backwards for the first time ever. Only got 4 qualifying laps in, had the lead in the race and missed a turn, hit the curbing and went off and came back on the track backwards. That put dropped me back to only 3rd (3 of us had a good margin on the rest of the 20 + group). The splitter detached from the car and the radiator ducting was dragging in front. Lucky me I did not get flagged. Somehow I managed to work my way back and take the win. Can't complain!

I've already started the new splitter and should have finished pics by this Saturday. So far I've spent $67 and will do it under $100. The wood I used was $35 for a sheet. It's hard to beat a Speedsource design splitter but I'm making two changes to 1) improve air flow to the radiator (none of those IT rules to mess with) and 2) more "off track" friendly. I don't know how to stop my exhaust from getting crushed though, I guess I should learn to stay on the track or get more than the 5" ride height.

 

good job on the win! Was that the only damage?

 

Don't let anyone give you **** about using plywood. That's the way Speedsource builds their's and no one on this board is going to out-engineer or out-spend them.

I went through a bunch of fiberglass splitters from different sources until I got one from ISC. There's mowed a lot of grass and always came back for more. It's a damn stout piece if you ever want to try it.

 

Are you going to cover the next splitter in fiberglass?

 

Thanks. The only damage was what you saw and a slightly crushed exhaust which is being replaced, of course a setup check as well. The nice thing about this splitter is that it's easy to repair/replace, virtually indestructible and cost efficient. Imagine if that had been fiberglass, you'd be buying a new one. Instead, I can just build one pretty cheap. If mounted correctly (too frame rails and bumper support, not the bumper covers or fenders) you don't tear anything up in an off course adventure. I'm making my mounts even more rigid than before with thicker aluminum, raising the splitter up some by eliminating the 1.5" air dam part (better clearance) and extending the splitter back to the radiator (can't do on the FC with IT rules).

I had this fiberglass air dam/splitter combo below, never again. The fenders would buckle, bumper cover would tear and the fiberglass would break. I did that 2 times and the 3rd, left the splitter at the track. The key is a solid splitter that won't crack, bend or break (wood is a better choice over aluminum or fiberglass IMO) and that won't tear up other parts of the car if it catches and gets displaced by a curb or whatever.

I am not covering the new splitter in fiberglass, I covered the old one in fiberglass resin but it's difficult to apply smooth and requires lots of sanding. I am trying some spar varnish designed for boats on this new splitter, maybe 3 coats to get smooth and hide the wood grain, then will paint black again.

 

Splitter #3

Couple Notes...
Superior mounts, enhanced design. Splitter is removable with 6 quick release pins. Bolted to the splitter is 1.5" x 1.5" x 3/16" aluminum angle which attaches to 1/4" aluminum plate with 3/8" quick release pins. The plate is bolted to the chasis. There are also 2 adjustable supports in front with quick release pins. No longer is there a 1.5" drop down air/dam , the splitter is flat and sits up higher for increased clearance. Furthermore, the splitter extends back to the bottom of the radiator now (not ITS legal - but I left ITS class)

Splitter is made from furniture grade 1/2" plywood covered in 3 coats of marine varnish and then black paint . I did go over the $100 but I was not building this for cost, but rather design. You could leave out the thick aluminum and SS hardware, that would save a few $$.

 

I wonder if you could use the radiator ducting allowance to argue that such a splitter is legal in ITS?

 

I've had aluminum ducting - a couple times. It works good but not needed with this splitter since it extends back to the radiator.

Aluminum ducting is legal IF it attaches to the splitter and radiator only, those are the "free" items. Ducting that attaches to part of the chasis would not be legal b/c there is no allowance for radiator ducting. If it attaches to the radiator and or splitter it's argued to be "part of" the splitter or radiator allowance.

 

Update:

Splitter install complete. Base/clear paint job at work. Oil cooler installation with proper ducting is next.

 

I must say, that looks pretty good..

What is it sealed with?

 

i know this is kind of old, but mazda used dense foam for the S4 sport package, wouldnt that work pretty well?

 

I sealed it with fiberglass resin thinned with lacquer thinner to help it lay flat. Three coats (might be able to get away with just two), block sanded, sprayed with base coat black and clear coated.

Once I see how this one works I'll see about putting together v2. Items looking to improve are high density foam for the risers instead of wood to reduce overall weight, and possibly improving the mounting system so it's easier to remove/install for better trailer access.

 

^^
Thanks. I wouldn't mind messing around and trying to make something for my s4. s4 bumpers aren't the most interesting..

 

nice work, inspirational actually, it's hard to find a splitter for the s4 , i'm gonna play around with some designs.

 

great build really informative and motivational (i know this is really old but i sent you a PM)

 

SCCAITS

u got more info loving what i see

 

PM me your email and I'll send some pics on Monday. I just finished a new splitter/air dam/ducting about 2 weeks ago.

 

I'd give you $40 paypal if you made idiot directions. Paper/cardboard cutouts of the pieces that I'd need w the thickness of what I would be cutting it out on the stencil. + a list of hardware.

 

Mint Splitter if Plywood is good enough For a 200mph skyline im sure its fine for a rx7 lol i think fiberglass covered Foam would be bad idea way too weak 17 pounds is a small price too pay for this setup

 

^^ id pay for some SCCAITS instructions, im not very imaginative, even with the pic i have

 

Not picking on this particular post but just inserting as a base for my discussion. Fiberglass is not light, wood is much lighter. A splitter should be 1st stiff, 2nd cheap and 3rd light. If it deflects due to aero forces it may work against you. Cheap for a racing disposable item speaks for itself and light is faster .. accelerating, cornering and braking. Stiffness mainly comes from section moment of inertia, the thicker the stiffer. A 1/16 inch steel plate is strong but will bend, an 1/8 in thick Alum plate will be stronger than the steel 2/3 the weight while being about 4 times stiffer. A 1/4 in plywood board will be about ½ the strength of the steel plate while stiffer again and 1/3 the weight. Fiberglass has a similar density as to aluminum. The ideal would be to use the practice of the aerospace and yacht racing industries by using low weight balsa wood (cheap), urethane foam or alum plastic or hexcel honeycomb (expensive) between stronger thin skin sheets for strength (single layer fiberglass or 1/16 veneers of wood plys. In way of mounting points replace core with plywood blocks.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>
<o:p></o:p>