Typical minimum oil pan clearance

[A ron]

What is everyone's minimum recommended oil pan ground clearance? Putting together a new to me car (wet sump) and have swapped midplates which helped but still looks too low to me.

[Mopar DLM]

slightly above the crossmember or right front frame rail which ever hits the ground first on your racecar. have you already checked your center of gravity with the new car. might not have to worry about clearance.

[Jking24]

How do you check your center of gravity ?

[A ron]

Thanks, it may be higher than the cross member but definitely not higher than the frame rail. I'm at 3 1/4" clearance right now. Was thinking it was closer to 4 in the old car.

[Mopar DLM]

lots of ways to check it. Billit can probably break it down on how in simple terms

[95shaw]

How do you check your center of gravity ?

http://www.longacreracing.com/technical-articles.aspx?item=42586

should give you the idea.

[billetbirdcage]

lots of ways to check it. Billit can probably break it down on how in simple terms

explanation: http://www.longacreracing.com/techni...spx?item=42586

Calc to type info in and get results: http://www.thedirtforum.com/centergravity.htm or https://robrobinette.com/cg_height_calc.htm


If you have different engines, I do the engines themselves to have an idea of how different each style of engine is and keep track of each COG and total weight so I know rough engine placement height and left to right position to keep COG the same. This is more important if you have widely varying engine sizes (long strokes vs short - IE crank weights), materials (steel vs aluminum blocks/heads), and/or styles of engines.

I just have a dimension from the bottom of the pan to the COG height, then to compare I just subtract the pan hieght to get a reference from the bottom of the blocks pan rail.

That's just my way of doing it.

[billetbirdcage]

Ron, it's been a long time since I messed with a wet sump engine in a car so going off memory which is crap any more, lol.

I'm thinking 1" maximum below the cross member at the back part of the sump but obviously cross members vary on heights with old vs new cars. (this measurement is with an older car that doesn't have a high cross member) But like mopar said you want the front of the pan to not be below the cross member.

If in doubt, just pull the RF coilover and let down on ground and jack LR up to chain and see roughly what hits first, it's not perfect but will give you an idea how close the pan will be to the ground and what hits first. Then just use you judgement on if it looks too close.

[Matt49]

Not to get too far off topic but are any car builders out there even giving out a recommendation on VCG? I've never seen one. Obviously it is important but it just seems like they always give suggestions on where to put your motor and ballast but never what number you're actually trying to hit.

[billetbirdcage]

Not to get too far off topic but are any car builders out there even giving out a recommendation on VCG? I've never seen one. Obviously it is important but it just seems like they always give suggestions on where to put your motor and ballast but never what number you're actually trying to hit.

I've never seen one given from pretty much anyone, ever.

I really haven't had to do it much lately since the hieght varies at least what works for me between different cars, drivers, and typical tracks they run. So I really haven't found a set height that works for everyone.

Mostly before I had to do it to figure out different motor combo's when we used to swap between a SAS style spec engine and an open engine. We was really happy with the car with the spec package but just seemed to be off a little with the open engine in these particular cars. We had the open engine 1" higher then the steel block Spec engine and after I checked it the COG of both engines and found out they where the same, so we lowered the open engine to the spec engine height and the car reacted much more similar to the spec package (at least as far as you can compare a 150# lighter car and 12" spoiler vs open).

Opps, forgot the mention the 100# we needed to add for the open engine was also to high to keep the COG at the same height, so lowered that also with the engine.

[A ron]

With the RF spring off, the Control arm hit the frame before the pan could hit the floor so hopefully will be okay.

[Mopar DLM]

how close was your nose piece to sealing off with the RF bottomed out

[A ron]

The bumper is off right now. It's really cramped in my shop with two cars so that made it easier to do the swap.