Homemade Splitter Design and Mounting
 

I'm in the process of making a splitter to go with my nismo V2. I was hoping for some help along the way to make sure I'm going about it in an ok manner. And it may be a reference for future guys to show the best mounting methods down the road.

My progress.

Pulled the car up on the lift on top of some oak plywood as a template. Back up 4" and I've established the outline.
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So the template is underway
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and I picked up some 6mm alupanel as the real deal
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To make sure the template was symmetrical I got some paper and traced the outline. I then folded it down the middle to make sure it was the same left to right since the oak template was based on a free hand tracing.
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I haven't trimmed the oak symmetrical yet. And I may not bother. Save that for the alupanel sheet.
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I'm starting to think about mounting and this is where I need a little help from those of you who have done it before.

At the rear I was wondering if these two screw holes could be used? I could get a slightly longer screw from a specialty fastener shop and place a washer between the splitter and the frame?
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At the front I've seen a lot of people drill into the front crash beam and mount supports there.

I was wondering if the beam could be removed and these holes could be used to mount a custom plate that would extend down and make an "L" so that bolts could be used to secure the spitter at the front.
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Comments please. And post photos of your mounting solutions.

Looks good. Gonna do this soon but on another platform.

i wouldnt use those large bolts, they look like they connect the brace to the subframe. id use the screws for the splash guard.

I don't know why you guys don't just use the zspeed undershroud it covers the same area ?

I wouldn't use the lower crash bar bolt as a spot to make a hanging bracket. Rather mount off the strut bar! Not sure how heavy that alupanel stuff is, but two beefy hanging mounting bracket should be enough next to mounting it to the bumper and chassis.

I slept at a holiday inn last night

This Will also work as a splitter/undershroud.

Needs to be stepped down off the bumper to clear the sway bar. My rear mounts are going off my GT Spec tie bar ( about the only thing it's good for) front mounting will be off the bumper beam, also mounting straight down off the edges of the beam. Then additional braces off the frame rails just in front of the sway bar mounts.

seems like alot of work that yeilds a headache and hardly any gain and may look bad. is the APR Splitter not good? never researched splitters that much but i know shine auto makes a cf full undersheild/splitter for the amuse rep.

+1

Adding a splitter to the undershroud I think would be less painful. Then again I knows nothing regarding track use.

In for more!

APR is what $400?

going off the track (which happens every once in a while) usually leads to breaking splitters etc. Thats why im doing a custom splitter out of ABS plastic. I had a amuse bumper with the splitter, went off at thunderhill and broke splitter..well there goes $300, if you break a wood or ABS plastic splitter its like $40 :icon39:


atleast thats why I think people dont just buy APR splitters.

and from what I have seen at track days, people with wings without splitters have unbalanced cars and understeer a lot.

Hardly any gain? Just downforce on the front end. May look bad, this is for track cars not the typical limp wristed nancy boy crap.


I'm actually running the front section of a Basically a Z speed shroud just to brace the bumper and properly channel air to the radiator.

A proper splitter is not really mounted to the bumper, it must be hard mounted to the chassis. It needs to be able to support a minimum of 200 pounds of downforce.

In for progress

Fixxxercask has a good one, maybe he can chime in

I should add the reason I was hoping to avoid the use of the front crash beam was incase I wanted to add a supercharger later, I wouldn't have to redesign all the reinforcement at the front. Just use the front crash beam supports that bolt to the chassis. Have a plate or bracket machined and go from there. I see what you mean about having to clear the front sway bar. How much clearance is enough? 1 cm? I'm still up in the air about how to properly secure the back. I was thinking of using the screw holes for theundershroud, but this thing is huge. Just want to make sure it's strong.

And for those asking "why a splitter" this is the easiest to understand drawing I've found.

http://projectimport.com/wp-content/...2/Splitter.jpg

It makes use of the high pressure, compressed air on the front of the car, and impedes it's flow downward.

A net downforce is created. Sometimes a couple hundred pounds.

nice...this has got me thinking about making that rear diffuser i wanted to make.

OP: how much did you pay for your alupanel? How much did you end up buying? I wanted to make one out of ABS plastic but not quite sure if it'd be strong enough.

Looks great OP! Keep us updated. I have been following your build :thumbup:

ROFL!!! terrasmak for President!

Yes, a splitter can add front down force but a lot depends on ride height, how well that ride height (and pitch) is controlled, and whether diffusers are added to the back of the splitter. Generally a splitter that's over 3" above ground is not working as a splitter anymore. Its acting more as a big front spoiler. You can help that by adding two short diffusers that exhaust into the front wheel wells. Some examples here:

http://www.google.com/imgres?start=2...48,s:200,i:148

One sheet was $175. Probably a lot cheaper in the US.

Good point on the ground clearance. I will have to measure when I'm mocking things up.

Im probably going to have to pick your brain a bit for the fabbing of mine. Also sounds like i may need a bit more rear spring for pitch control. I know i get a lot of squat from acceleration and from the rear wing at speed.

I agree but the nismo front end has a pretty big "plow" as is and yes it needs to be sturdy but a diffuser as he is building that will sit 6-7in off the ground seems like it will still allow alot of force under the car. Especially when your WOT and the front end is up even higher. Maybe I'm seeing it wrong but maybe making it angle toward the ground would make more sense to me but again I'm not a track whore.

In for finished product OP