Sump Guards.... or

[6speedmanual]

May protect from stones hitting oil filters pipes etc.

May prevent a stone getting into a dry sump or alternator drive belt

act as a skid plate on road rather than the sump pan.

A sloping leading edge may help car 'ski' over a solid raised object like a catseye instead of the square leading edge of the sump smacking straight into it.

 

Adds extra weight to the car in total.

Adds extra weight over the front wheels which makes it dive more under braking and under suspension compression due to road undulations.

Induces extra understeer due to extra weight on front wheels and CofG being further forwards.

Reduces ground clearance - guard likely to make much more frequent contact with road than the sump pan. Some really hard grauches of the sump guard could be induced in a situation where the sump pan would not even have hit the road at all.

There has to be a gap between the guard and the sump pan - this is to accommodate compression of the engine mounts and upward spring of the guard on cantact with the road. If the gap is not big enough, the guard and the sump both effectively clout the road - the guard first then the sump hits the guard.

 

Alternative solutions....?

 

1) Raise engine in the bay: I have just sucessfully found 7mm. I now enjoy 72mm clearance under my K series dry sump pan with CR500 tyres. This can be reversed in about 20 minutes if the standard engine position is desired for trackday or sprint/competition driving on tracks without grounding risks.

 

2) Skid plate fitted directly to bottom of the sump pan: I have not yet done this mod but it is forming in my mind. As one of the problems is gradual scraping away of the soft ali sump material, I believe there is some benefit of putting on something much harder so when it does scrape the road the amount of material removed is much less. Also the hard strip (as a sacrificial element) could replaced when it wears through. The design of the hard strip could have a curved, raised lead in ramp (much like a ski) to help raise the leading edge of the sump over any solid immovable blocks such as catseyes. I envisage this strip being made from 1.6 or 2mm stainless steel sheet, just wide enough to match the width of the return trough in the bottom of the dry sump pan. Could be bonded on with some type of epoxy resin adhesive. The total space occupied by this 'hard ski' skid plate could be as little as 2 - 3mm. This would preserve the ground clearance and minimise any ground contact. With the raised engine, there would still be 4mm more clearance than standard previous set up.

 

Thoughts / comments / suggestions / debate 🤔

 

 

Peter

 

 

 

 

 

BRAWNGP green SUPERLIGHT

*tongue*There's no such thing as too much IQ per Pound 😬

[rgrigsby]

I've run with a small bit of ali checker plate flooring bent 90 degrees and bolted at the front of the sump for several years now. It's take the worst of the impacts from the road and I'm sure has saved my sump more than once. However it's only a very small bit so it only protects the front.

 

Cheers

 

Rob G

www.SpeedySeven.com

[Bilbo]

Well mines not the same engine but for years I have a 4mm M/S plate brazed to the bottom of the dry sump pan.......... its a bit thinner now in places

 

---

'Can you hear me running' ......... OH YES and its music to my ears 😬 😬 😬

1988 200 bhp, 146 ft lbs, 1700cc Cosworth BD? engineered by Roger King, on Weber's with Brooklands and Clamshell wings, Freestyle Motorsport suspension.

[7 wonders of the world]

Ditto the above mine runs the full length and mounts onto the chassis on the lower crucifirm area - takes the worst out of any inpact and spreads the load of the impact over a wider area to save punching a hole in the sump.

 

Too young to be old !

[Irrelevant]

I have a 12" wide one made out of 4mm dural that runs from the front axle line to the front of the floor . . . can't weigh more than 2kg. That's well worth the protection it gives.

[TobyCoulson]

Make it out of Lexan. Much lighter than metal and arguably stronger.

[k80rum]

Surely raising the xx kg weight of the engine, bellhousing, etc up is going to be worse for handling than half a kilo or so of weight added extremely low down isn't it

 

I for one can't see the negligible weight of a sump-guard inducing understeer, or having any discernible effect on handling. it might shift the centre weight further over the front wheels, but only by a percent, if that..

 

Lexan/kitchen chopping board must be an ideal substance for protection and durability vs weight. There's an aftermarket Caterham part for Cosworth-sumped cars which acts as a bull-bar in front of the sump which is another interesting variation, since it employs a fairly small amount of material to do the job.

 

For what it's worth I've only managed to clout my sump twice in 10 years; both times were on the centre of a heavily cambered road, 2 up and under breaking - so when the front suspension was in greatest compression. A guard has got to be great piece of mind though.. I was thinking of adding weight in the form of a prop-hoop for just the same reason.

 

Am arguably costly but effective solution would also be to have a set of 15" wheels for the road and 13" for the track, especially if transporting the extra wheels is an easy option. I suppose that would mean different sets of cycle wings though . The speedo would also be out, but could be set for the 15" road wheels, where it would matter.

 

Darren E

 

K80 RUM Website and Emerald maps library

 

Home of the long-term, supercharged Duratec project

 

Edited by - k80rum on 29 Apr 2009 22:54:23

[Bricol]

Surely it's easiest to simply run a sensible road ride height?

 

We've got some terrible back roads around here, and I ground the integrale out more often than the Caterham.

 

Caterham just touches one of the car park speed bumps if I go slightly too fast and resulting suspension compression just taps the sump on the top of the bump, but in 8 yrs I think I've battered the rear towing eye into the ground more often (most mermorably while power sliding around a hair pin going up the Stevio Pass )

 

Bri

[Willie.]

I agree with Darren, I would definetly rather have a sump guard than raise the engine. A kilo or two that close to the roll centre is not going to make much of a difference. Rasing the engine, however, would.

 

I think sump guards are good. They give peace of mind. When I'm driving mine I constantly worry about the sump thumping things, so while I'm putting it back together, I fully intend to fit a sump guard.

 

Haven't quite decided how best to make it, or what material. Can't help thinking alumium flats (1 1/2 x 1/4" ) on their side, with 3/4" spacers at intervals, so it looks like this viewed head on:

I I I I I

Would be light, strong in a thump, allow sump cooling...but take bloomin' ages to make.

 

Willie

[Jason Plato]

I used to run a sump guard, then I changed to 250lb front springs (150lb std) and havnet had any real issues since. I've had a few scrapes over huge cambers and entry to carparks etc but no smash bang whallop moments 😬

 

here is my Duratec R .... C7 TOP

Taffia joint AO with Al

 

[nickh7]

many less hits now running Freestyle and 4x4 mode 😬

 

Fuel your Addiction here

[Mick Day]

250lb front springs