How deep is your front splitter?

[HRG]

As per the title, I'm just making a splitter up for the Griff and I wondered how deep the average splitter is. Unfortunately I'm all out of wind tunnel this week so I'll have to rely on 'best guess'

[Bluebottle]

Mine's about 15-20mm thick along the leading edge, if thats what you mean?

[img]
ignore the scuff marks on the rims, oh and the duck tape on the splitter (mates electric gates slam plate was higher than I thought)

Edited by Bluebottle on Wednesday 15th April 18:28

[stimshady]

nice horse!

[HRG]

That's some serious splittage I was actually referring to the smaller lip type some people use although if you can do speed humps with that I've got nothing to worry about.

[Bluebottle]

ah, the lip spoiler on the trailing edge of the hole underneath.
Mine was a Fibreon one which was about 3-4mm thick fibre glass, but 2mm Ali or plastic guttering work just as well.

[HRG]

I'm making mine out of this. I'm thinking about 30mm should suffice?

[rigga]

As mine is missing,ive no idea what form this plitter should take,got lots of ali i can source from work,so might nock one up.... any pics or dimensions of the original?

Wont try to mimic bluebottles though......

[RichB]

Hangs down about 2"...

[HRG]

Is that an original? How's high speed stability with it?

[RichB]

Yep, a strip of ali about a meter wide and folded down the middle then pop rivited in place, stability is fine up to 145-150 not had it any faster.

[HRG]

Yours is about 20mm deeper than the one on my E39. Sod it. it's easier to cut off than cut on

[Seasider]

Never noticed much more stability with mine lowered knocks a good few mph off top end though

[HRG]

I'd like to be able to get close enough to top end to find out

[Bluebottle]

HRG said:

I'd like to be able to get close enough to top end to find out

What radiator do you have, and is it properly cowelled so that the air can only pass through the circle of the fan blades?

When I fitted a fully cowelled Radtec it had by far to most positive impact on high speed front end lift.
Air cannot escape from the top of the engine bay so have to travel back down the bulkhead and out the bottom creating lift, reducung the amount of free flowing air into the engine bay that is actually not doing any radiator cooling will help. I have also chain drilled the rear lip of the bonnet to allow air to escape at the top. You could also fold down the front edge of the metal vent grill to create a 1/2 inch gap, also raising the bonnet catch plate to increase the gap help.
I did all the above to help get rid of the supercharger heat as i didn't want chimp vents in the bonnet, but it has all helped with high spedd stability.
Actually, coming back to the lip spoiler, that was the first mod I did for stability and it had naff all effect. I believe that what the lip spoiler was intended to do was to help stop air spilling out of the nose cone before it had a chance to go through the rad.

Edited by Bluebottle on Thursday 16th April 09:29

[HRG]

She's fully cowelled but I'm not sure if any air can escape or not. I'll double check that.

Very interesting comments about airflow as I have two potential locations for the splitter. One follows the natural radius of the nose deep under the car, the other follows the line of the front horizontal chassis crossmember.

Which do you think would be more beneficial?

[glow worm]

I understood the std. splitter on my Chim (by that I mean the bent bit of ali, that I knocked off last week) was there to cool the engine and nothing to do with stability. A difference of 10 degrees with or without at prolonged speed was mentioned. The wing splitters on my Tuscan , I would suspect as there for both reasons, since there's a cut out in the grill to allow air to fall off the inner edges of the splitters into the engine bay.

[RichB]

I can't really comment on the effect of not having the splitter because on the one occasion I knocked it off on a French road hump I screwed it back on with a day or so. That said I find my car perfectly stable at high speeds, tested on roads and tracks so perhaps it does positively affect stability or perhaps it's my Nitron suspension and the geometry set-up? I have no idea

[HRG]

I've got Protechs, poly bushes etc. and it's still bloody scary over 120...

[LordGrover]

If my Griff ever went to 132mph, which clearly it hasn't, it was would be terrifying. I expect. Probably. Especially on the M4 at 04:30 going down the hill to Avonmouth. Which never happened.

[RichB]

Seriously I've done a constant 145 in Europe for about half an hour with no worries and 135 - 140 at Bedford track day on the full back straight. I can't believe a small strip of bent ali would make that much difference yet I'm no Mr Macho and I'd have backed off it was scary Strange that there should be such a difference?