Oil pan clearance
 

I have a 1990 Miata that I am putting a 302 into. For the standard install to work the oil pan hangs down 3inches or so, which limits ride height. The other option is to lift the motor which further throws off balance and means I have to cut a hole in the hood or run a goofy cowl.

I considered running a dry sump system, but that is proving to be difficult and expensive. Another person suggested an external oil pump and slim pan, but I don't see what the difference truly is. Yet another option suggested was to "wing" the pan and go wide with baffels around the sump for the pickup but I have no experience with this and am unsure how to do this or how much clearance it would give me.

I have spent countless hours on forums and the old Google box without anything that really pleases me.

The goal is for the car to ride as low as possible with the motor being mounted as low as possible within the car and the stock hood intact.

Anybody have knowledge or experience on any of these?
Anybody have any other ideas?

I like the goofy looking cowl hood idea. The rear sump on mine does not hang lower than the sub-frame, but the drain plug does. The engine will only go so low before the pan hits the rack or frame. I guess you will need a custom sub-frame if you want to go lower.

pics would help

There isn't much to take pics of... Nothing is installed yet, because I am trying to figure out the best setup/ install fab. I am just going off research, others experience and advice, and educated guesses.

when i was installing my motor it was in-out-in-out-in-out-in-out. every time i put it in i hopped it was my last time taking it out lol. so just stab the thing.

I'm not sure what a "standard install" really is, most are "custom" to a degree. With Martin's kit, the ground clearance is really determined by the exhaust.

Exhaust issues aside, the practical low limit at the rear of the motor is the bottom of the bellhousing, which is more or less the same as the bottom of the stock pan. So even if you "shorten" the pan, there's not much you can do about the bellhousing/flywheel. You can move the drain plug to the side, that's worthwhile.

At the front, the low limit of the motor is determined by the pan's interference with the steering rack. It's not a good idea to move the rack, so you are pretty much stuck there as well. You can gain a small amount, less than an inch, by modifying the pan. Some feel it's worth it, others think the stock pan depth works as well.

The rearward limit is really determined by the same steering rack interference, this time with the oil pump. You can gain a small amount by modifying the front sump of the stock pan, allowing you to move the motor back somewhat, again, less than an inch, until it hits the firewall.

Many have used the stock pan, lowering the motor until it hits the steering and then raising it up slightly. You don't need much clearance, two credit cards come to mind. Same for the rearward positioning, just slightly clear the steering rack at the front sump.

Pretty much no matter what you do, you will have to cut some of the bracing out of the hood, not a big deal.

If you're after a "slammed" Miata, be prepared to cut a hole in the hood.

Mike

^^^^^What I would have said^^^^^

-Jason

Thanks so much Mike, that is some very specific and useful information! I guess I will just have to decide what is more important. Although I really like being low I don't think I will like a hole in the hood and have yet to see a cowl I liked... As for exhaust, has anyone ever used the oval or pill shaped tubing some places are offering now? Not that you will make huge gains clearance wise, but every little bit helps.

One of the first LS swaps documented on the "other" forum used some oval tubing where required, which is typically from the collector area to past the transmission, where it becomes roomy enough to tuck the exhaust up a little. He also used solid mounts for the engine/trans which made the exhaust somewhat easier.

Mike