Team Babel: the MR2 Mk1 project begins

The first key is keeping the motor from overheating (again). If you're running the stock radiator, get it to a shop and get it cleaned out of the 25+ years of crap that's accumulated in it, all the stop leak and other gunk is working against your radiator efficiency. Flush out the entire coolant system and make sure that your water pump is working properly. Find a way to get a real oil cooler on there -- in fact, shoot me an email, I probably have a spare sitting around that you can have for very very cheap. When you're rebuilding the engine, build a spacer for your oil pickup tube so that the screen is about 1/8" off the bottom of the pan and that will help with the starvation issues. When you do the rebuild, use a lot of Redline assembly lube on all the bearings and cam caps, I'm certain that helps. We got 85 race hours on the engine we rebuilt after the one we blew in the post you quote and I did all of that on that rebuilt engine.

Also, vent your radiator up through the hood. It will get much, much, much better flow through the radiator rather than the flow running right into that "firewall" right behind the radiator. Vent that firewall and then send the flow up through the hood. It will also help to reduce front end float at high speed.

Then keep the revs in a reasonable range, by which I mean think about putting a shift light on the motor set for 6500-7000 revs. You can't shift that engine at 4500, it doesn't start developing any power until north of 3000 rpm. You've got to take it to at least 6500 if you don't want to be a total slug, and it doesn't redline until 8000 so you've got plenty of room above that 6500 shift point.

Get a good alignment on the car. It is very sensitive to bad toe-out. I've had success with the toe at dead zero in back and at about 1/16" in (per side) on the front, but mine is pretty lowered at this point. You might want to go with something closer to the factory settings if you're running the stock suspension. Max out the camber on all 4 corners (using the eccentrics) and then set the front toe to zero and the rear in 5mm (those are the factory settings). But the alignment is critical on this car, with it's short wheelbase it will swap ends without a lot of warning if you make the (common) mistake of jumping onto and then off the accelerator and onto the brakes. It doesn't like rapid front-rear weight transfer

Feel free to shoot me an email with any more specific questions. Cheers!

There's a lot of good info at MR2OC.com and you can probably find a downloadable copy of the factory service manual a/k/a the BGB (Big Green Book) there too.

Definitely remove the A/C. Just extra weight for no good. Yeah, an Elise-style hood would work fine. If you don't feel like slotting or hole-drilling the firewall behind the radiator, you can cut the entire thing out. Just cut above the line formed above the spot welds at the bottom  and on the sides and below the obvious lateral crease at the top. We've run probably 6 races without it at all and haven't noticed any front end flex/twist as a result. I did weld in a piece of roll cage tubing across the frame members in the frunk, just to make sure.

For the oil cooler, what I did was put a sandwich plate on the oil filter and ran the oil cooler out that way. You can put the engine cooling fan on the oil cooler, as it does jack squat for cooling the engine while the car is in motion. It's only there to help keep down engine bay temps in stop and go traffic. In terms of oil, it depends on how worn your engine is and how well you get it cooling. Mostly I pick up whatever is the cheapest full-synthetic oil I can find, but then I change it after every race session. I got a bunch of Royal Purple 15w40 on sale for $4.99/quart last summer and have been using the crap out of that, and it seems fine. Redline will tell you to use 30w, a bunch of forum guys swear by 50w. I think 30w or 40w full synthetic is fine, but you might want thicker if you're going to be racing in hotter temps.

You can find a pretty common air intake mod (and AFM mod too) on MR2OC. I think you'll see that nobody uses the stock around-the-car air intakes. You can put the oil cooler in the spot on the right where the engine cooling fan resides/resided if you like. You can leave the engine fan on its stock relay and controller and let it decide if/when to turn on, or slave it to a dedicated relay, which is what I did.

For the sump spacer, I did mine on a bandsaw too, and basically exactly as you described it. Then I shimmed the legs that hold the oil sump screen with extra washers.

The front brakes will overheat if they don't get air. It can be hard to get them ducted due to the frunk, but if you just cut openings in the air dam to let some fresh air in, that seems to be sufficient at most tracks. The only one where we've had any real brake problems is at ECR, but EVERYBODY has brake problems at ECR, so it's not and MR2 issue (for once), that's a track issue. The rear brakes are only marginally functional on most MR2's in order to reduce snap oversteer. You can remove the brake prop valve inside the stock prop valve body that's located on the driver's front strut tower, but to be honest, I haven't found that it really makes much of a difference either way.

He makes some great points there. You will definitely need to get the head checked for flatness since you know that it's already blown a head gasket, you're pretty much guaranteed that the head is warped. Underdrive pulleys are a great idea too but hunt around for them to keep it under budget (the classified/used parts forums at MR2OC.com and at club4ag.com are both good sources). You can use any engine parts from the AE86 on your engine, so make sure to use that as a search term if you're hunting on eBay, as there are a lot more AE86 fans out there than MR2, and especially so on the West Coast where the drifting culture is stronger.

I like that oil restrictor idea. You know what, I have a kicked-out oil pan for the 4AG motor that I can get to you too if you want it. I think it increases capacity to 6 or 7 qts and is baffled and all of that. It could use a dunk in the acid-dip because it sat outside and got some surface rust on it, but once we installed that larger sump, we had no problems with oil pressure whatsoever.

Once you get it all put back together, make certain that you have bled the coolant circuit completely. You'll want to read the procedure in the BGB pretty closely. It's not difficult, certainly not brain surgery, but you will surely blow another head gasket if you don't get all the air out of the coolant loop. You really want to get the engine running as cool as possible (within reason) because when it gets really hot and at high RPM, you will get pockets of steam forming in the head (especially near the #4 cylinder), and then another BHG is a guarantee. If you can find a used aluminum racing radiator for any other car, it's worth modifying the radiator mounts and front end, but that's more advanced than MR2 101.

If you can use bossnova's airlift (or whatever he's using to pressurize the cooling system on the floor), I'd definitely recommend it. Working on the MR2 at the track, especially the cooling hoses, is really difficult due to the packaging of the engine in that narrow space. Much easier to do back at home/the shop. Cheers and keep the questions coming.

We pressurize engine assembly on floor with our head pressure testing fixture but if you have an air regulator w/gauge its pretty easy just plug hoses and use air regulator to apply no more than twenty psi 15 should be enough then spray suspect areas w/ dishwasing detergent/water mix and look for bubbles. We also fabbed up a surge  tank which makes getting air out a snap and gives us 3 qts more water capacity . It has small lines running from t/stat housing and top of metal pipe where old rad cap used to be then the return goes into bypass return to water pump. we fill it and run car the only bleeding we do is at top of radiator. I will figure out posting pics and post somtime.

My opinion is a more conservative approach for prepping an AW11 for Lemons racing. Most of the top finishes for the AW11 that I know of have been near factory stock cars. Lil Smokey And The Bandits, Motoring J-style both have several finishes in the top 3-10 and they are pretty much bone-factory-stock.

What year is yours? The bigger 87+ brake upgrade is nice, though we did great with stock 86 brakes in the Snowspeeder for several races. Good pads are more critical, IMO.

Cooling system is certainly the most common weakness, but the stock system works fine if it is in good condition. Leaks leading to cavitation are always the biggest problem, but the water pump does seem to have difficulty keeping up with all that plumbing. Pressure test, and take a tester to the track. Stick figure and V-RAM cars have both been fitted with surge tanks in the past, which would delay but not avoid over-heating. External electric water pumps have decisively cured our cooling problems.

Improving cooling air flow can't hurt, but it's not why MR2s overheat from what I've observed. Scoops are fun to make!

It's interesting to observe that the Corolla portion of the MRolla, running stock cooling (stock everything) has never overheated. Same engine and water pump, just less plumbing.

And welcome to the 24HL Lemons club. I think the aw11 is more fun than anything else on the track.

I wouldn't assume the stock oil cooling system is less effective than an air oil cooler without seeing temperature data. Water is a great conductor. That said all three MR2's I race have an air oil cooler tucked into the engine bay vent.

I also see enough 4AGE cars race effectively with stock oil pans and plumbing that I wouldn't mess with it. Nearly all cases I know of "oil problems" have be theoretical explanations on engines that were in questionable condition and/or had questionable mods.

What he said

We gutted the oe proportioning valve and added an adjustable valve in the line to front brakes.
Don't weld pass side door it makes it easy to help belt in driver and unless your tiny or an acrobat
You WA t to be able to get in that way to work on inside stuff.