Question for building under tray (full car length)

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hellangel
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Post by hellangel » Tue May 04, 2010 8:15 pm

lag waggon wrote:hellangel what model supra are you going to be running?


RZ 1994 (JZA80)

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V8 KILR - 721 rwhp @ 19 psi on pump fuel

blownvn
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Post by blownvn » Tue May 04, 2010 8:59 pm

I hope it's not going to have all that crap on it? :)

On a serious note though it would be a good contender for a quick salt car, just a little pricey to buy up front.

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hellangel
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Post by hellangel » Tue May 04, 2010 9:36 pm

blownvn wrote:I hope it's not going to have all that crap on it? :)

On a serious note though it would be a good contender for a quick salt car, just a little pricey to buy up front.


if by crap you mean the wing, no it wont have that wing on it.
V8 KILR - 721 rwhp @ 19 psi on pump fuel

David Leikvold
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nice

Post by David Leikvold » Tue May 04, 2010 10:23 pm

Terry, that looks like a very nice car and I see it is still registered. Are you really sure you want to put it on the salt? Of course, I understand that you probably want to run an essentially road legal car just to see what it can do. It's your call.

If it was mine (I wish!) I'd keep the plastic sills to start with but ditch the fake rear brake ducts. Then I'd open up the bottom of the rear bumper a bit to allow a proper ground effect style exit for the belly pan with some of those vertical fins under there to keep the airflow in a straight line. Speaking of sills you might want to consider changing them out anyway and completely filling the space between the front and rear tyres with a rectangular section sill that was parallel with the ground. If you kept them straight on the inside and out that would surely improve airflow. Time to start Googling ground effect skirts.

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Dave :D
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David Leikvold
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More random thoughts...

Post by David Leikvold » Tue May 04, 2010 11:22 pm

I was looking at the wheel arches on a Porsche 944 a while back. The trailing edge is angled back at more than 45*. Gripping stuff, I know, but if you did that with the sill fillers that would help spray more of the salt out the side and less under the car. While it wouldn't necessarily apply to your car other people could use the idea in Competition Coupe (which allows radiused wheel arches) to maybe tidy up the airflow around the wheel arch, especially when the track is narrowed and the wheel and tyre sit further into the wheel arch.

Side exhaust will solve the belly pan problem but I'm not entirely convinced of the merits of the exhausts that stick out the side of the front mudguard a very long way and then turn parallel to the side of the car. I understand why people do it, it gets the flame away from the paint and dumps the exhaust into the hole in the air that the pipe made. You might like to consider a variation on the side exhausts use by V8 Supercars. I'd run the pipe close to the front of the left hand sill and then have it dump over a long part of the sill to keep the gas flow reasonably parallel to the car. I've seen uncorroborated air flow CFD drawings that indicate exhausts pointing straight out the sides really ruin airflow down the side of the car.

My brain hurts now.

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Dave :D
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David Leikvold
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twojay

Post by David Leikvold » Wed May 05, 2010 8:53 am

Oh wait, a 2J has the exhaust on the driver's side of the head so run the exhaust down that sill but start the exit after the door so that people trying to tell you something important at the start line don't get burnt legs. Or you could make the whole sill/skirt part of the exhaust, make it in stainless and have hot rod style louvres punched in it to vent the exhaust. I like that!

Cheers
Dave :D
Good, Fast, Cheap, pick any two!

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