Dry Sumping and Lowering the engine

Joe Angers · 07-27-05, 09:58 PM

Hey folks,

I'm curious about something I've seen a few times on here. I've read some posts about people dry sumping their engines so they could lower it in the chassis.

It's an avenue I'd like to explore when the day comes I purchase a kit, but there are a couple of things that got me thinking.

First, engine mounts. Do most kits have fixed engine mount locations. How have you tackled it?

Second, tranny. I would imagine that lowering the engine would force the tranny to be lowered correspondingly. How does that affect the angle of the halfshafts? Or do you angle the whole engine/tranny combo to keep the halfshafts at a safe angle (a la TWR Jaguar XJR-8 or Aston Martin AMR-1).

Ross Nicol · 07-27-05, 10:44 PM

Hi Joe
There is a post of mine covering this. I think it'e called fitting ZF to RF.Anyway here's a short reply.You are correct, original engine mounts are removed,trial fit engine/transaxle as a unit to determine best driveshaft angle,then refit engine mounts etc.
Ross

Fran Hall RCR · 07-28-05, 12:16 AM

Joe..
the RCR monocoque chassis has an integral tank built into the left hand fuel sponson with the view to using it as a dry sump tank...just thinking ahead for you big guy.. [img]/ubbthreads/images/graemlins/grin.gif[/img]

Pantera1889 · 07-28-05, 01:08 AM

[ QUOTE ]
Joe..
the RCR monocoque chassis has an integral tank built into the left hand fuel sponson with the view to using it as a dry sump tank...just thinking ahead for you big guy.. [img]/ubbthreads/images/graemlins/grin.gif[/img]

[/ QUOTE ]

That will come in handy! [img]/ubbthreads/images/graemlins/wink.gif[/img]

Ross Nicol · 07-28-05, 02:21 AM

Fran Are you setting up your chassis for any particular drivetrain combination? My oil tank is at the rear of the fuel tank sponson so great minds think alike.I thought about the dry sump plumbing for quite some time and hose lengths are short and neatly placed.I even had the dry sump made with a cut out to clear a chassis crossmember.The best laid plans don't always work out though, I had to get the sump further modified to allow the starter motor to fit. Apart from minor oil leaks the system has been terrific.Dry sump is a must for a car doing a lot of track work, in my opinion and with the weight low in the car the handling is superb.There is a cost consideration Joe but if Fran already has a tank installed then that does help.The problem is if you buy a kit from a manufacturer
who doesn't normally have a dry sump option boy you have a lot of work to do.
Ross

Joe Angers · 07-28-05, 01:52 PM

[ QUOTE ]
Joe..
the RCR monocoque chassis has an integral tank built into the left hand fuel sponson with the view to using it as a dry sump tank...just thinking ahead for you big guy.. [img]/ubbthreads/images/graemlins/grin.gif[/img]

[/ QUOTE ]

Fran, you're a man after my own heart. That's great news. If I do choose to go dry sump, it saves me the trouble of finding a location for the tank, and frees up space up front for an A/C unit (your chassis can take AC right?).

I plan on my GT being used both on the track and the street (hey, why not show it off), and the benefits of dry sumping seem to justify the initial costs.

Paul Thompson 'Hooligan' · 07-28-05, 07:01 PM

Hi Joe / all -

If you ever run slicks on your car on track - dry sumping is a must in my opinion.. We log the oil pressure and even with supposed 'state of the art' baffled sump with trapdoors etc etc, the oil fluctuated a lot during excessive cornering/braking.

With the dry sump fitted, the motor gets 60 to 80 psi, regardless of G forces we've thrown at it. Remember most people would suggest 10psi per 1000rpm and you'd be amazed how low it can go without the d-sump.

When pushing hard, and concentrating on things other than your oil pressure guage, the oil can dramatically drop and in any case, the capilliary guages are generally fairly slow to respond. If you are unsure, fit a pressure switch to the block set it light a light if the pressure drops below about 30 psi - then see if it lights up during hard driving.

The pic below shows where Roy placed the pump on his GTD, together with the relocation of Alternator and loss of water pump (electric now).