Rear diffuser/splitter ideas?

I do not like how my twin exhuasts exit the car through two holes in the rear and this has bothered me for some time. I originally was going to cut a scoop from the bottom around the single tips, then recently I've liked the idea of having two lots of twin tips, like corvette, ferrari and most recently SSV style.

Now I know the concourse enthuisiests will cringe and call me names but I really need to do something with my rear end which may even include re-fitting a rear bumper. I've like the idea of a rear splitter as well but non of the pioneering examples on Hybrid Z have looked very good. Not only would the rear splitter be for looks, but performance as well as it would cover and protect the fuel system which is up under there. Now all you guys that already race your Zeds must have disccussed this as some stage?

How would you think one of these Holden/Pontiac rear diffuser sections would look if incorporated/tucked up under the rear?

These matt black sections are easily available and it seems I almost have exhaust holes in the same spot, there would just be room for twin twins. As it is from a Commodore they would be a little wider, but could be modified. The only other thing I see is Zeds seem flat across the back and these have a little curve.

http://forums.justcommodores.com.au/ve-holden-commodore-2006/121786-pontiac-g8-gxp-rear-diffuser.html

http://holmart.com.au/online/prod311.htm

it probably wouldn't look too bad but you are right about those exhausts there needs to be something there to split the back up. i would chuck the bumper of first and see how she looks.

cheers Pauly

You know I thought about building a composite diffuser for the Z.... But the dam tank and and exhaust make it hard to fit.

Not sure if you could get one to mount without it sitting outside on the sides of the lower quarters.

Sorry to zombie this thread but i was thinking alone the same lines. I have a shaved rear end and its just a bit too big, it needs some thing to break it up for they eye. I was thinkin a diffuser but something suttle. The one that looks best in photoshop is a VE holden hsv but single exhaust. Here is a photoshop. Could be feasible if it matches the body lines and size in real life

That looks great Buddy !

Cheap buy it now one on ebay for $66

http://www.ebay.com.au/itm/Genuine-HOLDEN-VE-Commodore-SS-REAR-BUMPER-BAR-LOWER-INSERT-/230725052187?pt=AU_Car_Parts_Accessories&hash=item35b848e71b

This has already been discussed somewhere on hybridz i believe.... The curvature is way out unfortunately. Ill try find the link!!

here is the link-

http://forums.hybridz.org/index.php/topic/93924-g8-gxp-rear-diffuser-on-an-s30/page__p__885081__hl__diffuser__fromsearch__1#entry885081

Here's one I prepared earlier...

http://www.viczcar.com/forum/index.php/topic,9059.msg86771.html#msg86771

Carbon fibre for an Evo 7 I believe, Ebay $280.

Had to cut a little bit off to clear my exhaust.

Haven't done any back to back testing to measure effectiveness, but I think it has given me some more high speed grip.

Necroing this thread again. I am very interested in a rear diffuser for looks only to break up the rear bumperless look.

Nothing that I've seen thus far looks particularly good. I think a couple of subtle curved fins would look good, rather than the sharp ones that jut straight down. The diffuser on the Toyota 86 looks quite good and would carry over well to the zed.

I think Chartoo was on the right track.

Would it be difficult to get something like this fabricated from scratch? Maybe I should drop Freddy a line.

What does the 370z's diffuser look like.

Keeping it in the family and everything.

Or even those new 350GT's???

Something like this? http://www.thezstore.com/page/TZS/PROD/350z01/50-1881

Although you'd need something that had pretty much no curvature for an S30...

Ive been on the lookout for something along these lines aswell.  I like the ve gts single pipe one.  Im running rb25det gear with only one exhaust exit.  Do you think that would look alright or?

I guess someone's got to be the first to buy one and see how it looks...

Yeah I wouldn't be too keen in buying one from another car and trying to make it fit...

Looks like the demand is there for someone with the skill to make up something good from scratch and make a dollar.

Who's good at photoshop?

Ive been on the lookout for something along these lines aswell.  I like the ve gts single pipe one.  Im running rb25det gear with only one exhaust exit.  Do you think that would look alright or?

As above mate... wont fit due to the curvature!!

Diffusers looks great on zeds but keep in mind even getting one specifically for S30 will require a fair bit of work to get it fitting correctly as 95% of rear ends have been bumped/twisted making it hard to fit up something like this.

Yeah I wouldn't be too keen in buying one from another car and trying to make it fit...

 

Looks like the demand is there for someone with the skill to make up something good from scratch and make a dollar.

*cough* Topstage *cough*. His area of expertise is fabricating functional aero, his dress up parts are a side business.

*cough* Topstage *cough*. His area of expertise is fabricating functional aero, his dress up parts are a side business.

freddy is certainly the man to see.... though from what little i know for a diffuser to actually be functional the car has to be extremely low to the ground(no 100mm is not low) so this piece would be purely for aesthetics. Maybe freddy can chime in on this??

Ben

The closer you are to the ground the more effective the underbody aero will be. It would not be noticeable on a road car because of the slower speeds obviously but if you were to put that same car on track with a rear diffuser even at a fairly high ride height it would make a difference even if it's just because the strakes are straightening out airflow.

Alternatively if you were to raise the rear of the car enough to give it some noticeable rake the pressure difference between the front and rear of the car will also create a diffuser effect. I toyed with the idea of creating under car panels to make the zed have a flat floor but it is much easier than it sounds, plus the old girl would be quite some way off the ground!

The 944 porsche had a intresting look

Gents I don't want to rain on your parade. But unless you have a real fast Zed and I mean real fast and take it on the track then I reckon you wouldn't notice any difference having a defuser. Unless you are just going for the look.

If all you Zed fans are after aero dynamics then you need to start at the front of the car. Not the rear. That would be with a G-nose. Other wise you really have a massive parachute at the front if you are running a standard front grill. Not enough down force with a standard front to even make a rear defuser work in my opinion. Then you would need a big wing at the rear to keep the wheels on the ground at high speed. Oh and you will need a fast motor as well. Then and only then would I be looking at spending money on a rear defuser. But even then if you are running a standard rear bumper you are creating unsettle air turbulance around the rear simply by the way it is attached.

Personal opinion only. 

^^^^ +1

Pretty much the only guy here that needs one, has one.

And that is Sinisha!

But I think they are talking about want, not need Craig. 

I just like the look of them, I was worried that the rear of my de-barred z was going to look abit plan.

But the diffuser will break that up, Im not too worried about performance yet

I quite like the look of it.