Ride height of F3 etc cars

[schomosport]

Several threads in recent months have discussed the running of cars at ride heights they were not designed for in order to comply with Monoposto/MSA regulations which stipulate a minimum ride height of 40mm. Can anyone tell me what the regulation minimum ride height is for a F3 car, if any? And has this changed over the years e.g. when they banned the aero cars in the early 80s and F3 manufacturers had to switch over to flat-bottomed cars, was a minimum ride height defined? Has this changed in the last 20 years?

[Neil1982]

The two manuals we have which are 88 Reynard and 98 Dallara both say for front ride height 'as low as possible'.

[THR]

yeaaa the legal limit is on the deck!
in practice its higher than that tho lol... about 20mm ish at the front and the back higher

[MikeBz]

A friend-of-a-friend runs a Reynard 913 in ARP, basically the lower the better he says. ~15mm he reckons, FWIW.

[JohnMiller]

Shouldn't the front just ground under heavy braking?

[Bob Pearson]

We reckon the lower the better with Formula Renaults, typically about 11mm at the front.Eventually formulas such as Mono will have to recognise that most cars available for them to use were designed to run, as you put it, "on the deck" and change their regs accordingly. Their alternative will be to become a"Classic Monoposto formula"

[MikeBz]

Playing Devil's Advocate slightly here Bob, but if the rule is the same for everyone in the formula then why not have a minimum ride height which allows cars to be moved around the paddock easily and means you don't have to replace your floor at frequent intervals? OK, maybe 50mm is excessive but having a sensible minimum seems, well, sensible (apart from the fact that it's another rule to police and have contentions over I guess).

[Bob Pearson]

Mike, you are right about the problems of being moved around the paddock, and the same applies to going off the track, we rarely make it back. I guess we are spoilt with the garages and I was speaking from that position. Most paddocks have improved enormously in the last 5 years, I would think only Mallory provides a problem although I haven't been to Combe for a long time. It still seems a shame that F3's FR's and no doubt in the future, the FR2000 have to be used in a way that detracts from their handling abilities and so must detract from the pleasure of driving them.

[schomosport]

Originally Posted by Bob Pearson

a shame that F3's FR's and no doubt in the future, the FR2000 have to be used in a way that detracts from their handling abilities and so must detract from the pleasure of driving them.

Didn't think it would take long to get there! Prompt for my question is acquisition of an RT30 which I will be running in Monoposto. The general consensus appears that for the Renaults and F3 there is no minimum ride height and hasn't been for many years (Neil's 883 reference). Just wondered if it had always been so and if the 'low as possible' ethos applied for my 1985 car. just curious to know how far away I will be running from its optimum configuration. Since I made reference to the ground effect cars whose flexible skirts were designed to touch the track (albeit under aerodyanamic loading) I guess I have probably answered my own question!

More than one person has advised that the car must also be run with about 25mm rake. Is this applicable to F3 ride height, Mono ride height or both I wonder?

It has been suggested to me that it is the MSA that stipulates a 40mm minimum ride height and that Monoposto have simply had to fall in with this requirement - the F3's are only allowed to run lower only run lower because they are running to FIA regulations. This may just be a smokescreen since I suspect FR run to MSA regs. not FIA.

Single seaters still being parked on the grass last time I was there...Cadwell is not that flat either. Personally I find running at 40mm gives me more than enough problems in getting the thing jacked up, in and out of the trailer, etc. without going any lower. But if I could I would!

[SpawnyWhippet]

Originally Posted by MikeBz

Playing Devil's Advocate slightly here Bob, but if the rule is the same for everyone in the formula then why not have a minimum ride height which allows cars to be moved around the paddock easily and means you don't have to replace your floor at frequent intervals? OK, maybe 50mm is excessive but having a sensible minimum seems, well, sensible (apart from the fact that it's another rule to police and have contentions over I guess).

The problem is due to the cars design (F3/FRen). They were designed to run at around 15 - 18mm front, usually with a rake of 15 - 25mm depending on what handling characteristics you are looking for. When you have to jack them up to 40mm front, with a 60mm rear, they look ridiculous and handle like a hippo with bad knees. (Personally, I'd rather struggle with the car in the paddock than on the track.) I had several years worth of discussions with Mono about this and got nowhere. Its not going to change in the near future either, although I heard rumblings they may allow alloy engine blocks at some point.

[Bob Pearson]

Which engines would the alloy block change allow in?

[JohnMiller]

Duratec.

[Neil1982]

"It has been suggested to me that it is the MSA that stipulates a 40mm minimum ride height and that Monoposto have simply had to fall in with this requirement - the F3's are only allowed to run lower only run lower because they are running to FIA regulations. This may just be a smokescreen since I suspect FR run to MSA regs. not FIA."


Mark has it in one. It is not Mono rules it is Blue Book rules that stipulate 40mm. Somehow ARP and BARC FR have managed a dispensation from the MSA. In 2002 when we were competing in the British Sprint Championship the BMSA asked the MSA for a similar dispensation for the mainly F3000 over 2 litre cars. This was declined on the basis that there was 'no safety critical' reason for doing so. I have to assume therefore that someone has convinced the MSA that for ARP and BARC FR there is a safety critical issue. Interesting that for a Dallara in ARP ride could be safety critical but not in Monoposto.

Something in the back of my mind tells me that the ride height restriction came in in the late 70s early 80s to protect the circuit surfaces from the then common titanium skids.

[Bob Pearson]

Neil, I guess the logic is that for ARP and FR you have no choice but to use a car which is designed to run at minimal ground clearance, but for Mono there are others which can be used. Don't think for a moment I am supporting that view, if it was left up to me the rule would be to run them "as designed".

[schomosport]

Originally Posted by Bob Pearson

Which engines would the alloy block change allow in?

Alfas; whatever the Mugen Hondas were derived from. These cars exists in F3 form but with few places to play: ARP F3 Masters looks close to collapse as many of the remaining runners have decided to sell their cars....
Does the Rover K Series exist in 2l form?

[schomosport]

[QUOTE=Andydickens](Personally, I'd rather struggle with the car in the paddock than on the track.) QUOTE]

Yes of course!

Now I've swiched from FVL to F3 i must be ripe for a kicking from you over ride heights.....

But seriously, unless you have acres of space these things are a pain to get off the ground aren't they! I have a reasonably sized double garage but still: move the tow car to get the doors open so the quick lift can come down; But it won't come down because there's a 10degree slope down to the garage; buy an F3 rear jack but it doesn't work because the diffuser is in the way; take the diffuser off and then stuff the nose into the ground because I forgot to jack the front up first; Oh joy!!!!

[MikeBz]

Re: 2 litre K-series: Only exists in BTCC spec (and a special Caterham variant) which is substantially (almost totally) non-standard. You wouldn't want to try to run a K-series to mono spec (even if you could live with the power deficit).

[Steve Wilkinson]

As an earlier poster said the cars of the late 80s and early 90s were designed to have between 15 and 20mm front ground clearance. The inference that the cars are dangerous when 'jacked-up' is correct and there has to be a lot of work done to compromise the set-up to make them handle.
However it isn't just the F3 and FRenault cars that run low. At a recent Sprint Meeting North of the Border several of the Mod Prod Westfields fell foul of the 40mm Ride Height Rule. Whereas most of the single seaters just about scrapped through.

[SpawnyWhippet]

Originally Posted by schomosport

Now I've swiched from FVL to F3 i must be ripe for a kicking from you over ride heights.....

Comments not needed, I'll wait for your pain!

Originally Posted by schomosport

But seriously, unless you have acres of space these things are a pain to get off the ground aren't they! I have a reasonably sized double garage but still: move the tow car to get the doors open so the quick lift can come down; But it won't come down because there's a 10degree slope down to the garage; buy an F3 rear jack but it doesn't work because the diffuser is in the way; take the diffuser off and then stuff the nose into the ground because I forgot to jack the front up first; Oh joy!!!!

Easy enough, get yourself an engine hoist / block and tackle and lift the car onto 16" stands or a wheeled trolley. I made a joist in my garage roof and hoisted the car onto a trolley.

[MikeBz]

I've never seen this rule checked or policed at a speed event. I've seen/heard plenty of cars scraping the ground though... It wouldn't be that hard to do at least a cursory check, just have a 'regulation' 40mm block that you have to drive over either in the scrutineering bay (if there is one) or on the entrance to the course. It's plain daft to have rules which can have a significant effect on performance which are rarely policed (and therefore regularly flouted).

[Bob Pearson]

I have never read a detailed report of what actually happens to an F3 or Fr when they are raised to comply with the 40mm requirement. All comments simply say they no longer work right. Having drawn out the various suspension scenarios ( we looked at joining Mono at the beginning of this year) it seems quite clear that changes to feel would be substancial, but what are those changes? Does it induce oversteer or understeer, turn in, mid corner or exit, lack of traction? What actually does happen. It is quite clear from the vast variations in lap times between Fr's in Mono and in Barc that something happens, but what?

[kickstart]

Having run a FR in F4 and occasionally mono for a couple of seasons they seem to handle fine at 40mm, but they do tend to be rather different as you tend to have to run them with much softer springs. The quickest my car has gone round BH is high 49's where as I read Ian Pearson was down in the 46's, I would imagine with a young,slim quick driver at 40mm they should still be capable of low 48's.

I suspect that the quality of drivers at the sharp end of BARC are somwhat quicker that the FR racers in Mono/F4, which tends to increase the gap. I remember a few seasons ago one of the very quick lads in BARC came 2nd or 3rd in his FR in the Mono race at Combe on standard Michelins, which I can say dont work so well at 40mm.

[Bob Pearson]

That was Josh Fisher

[diz]

Thought I'd take the opportunity to mention an open single seater race - see signature - that will not be constrained by the regulations for the various championships - and is an absolute bargain to boot.

Sorry to interrupt. I'll leave you to your discussion.

[schomosport]

Originally Posted by diz

Thought I'd take the opportunity to mention an open single seater race - see signature - that will not be constrained by the regulations for the various championships - and is an absolute bargain to boot.

Sorry to interrupt. I'll leave you to your discussion.

But it will still be constrained by MSA regulations won't it!!! I'm sure the local scrutineers are awaiting with joy all those overnight raised F3s and FRs that have entered.