1987 Toyota MR2 - Tech Support - Super Street Magazine

We know how difficult it can be to work on cars; believe us, we’ve had more than our share of problems over the years, too. Good thing we’re willing to share this knowledge of problem solving with you and act like we know something technical about cars. Feel free to ask us about any of your tech problems by writing to Super Street at tech@superstreetonline.com or Super Street, Attn: Tech Support, 831 S. Douglas St., El Segundo, CA 90245. We’ll try out best to answer your questions but can’t answer every one we receive personally or in print, so if your issue is urgent, we highly recommend you seeking the help of a nearby mechanic! Also, try to do some basic research online; while the Internet and forums aren’t all foolproof, it is a very good start as there are many excellent resources to look at. If it helps to include a few photos to describe/illustrate your problem/project, please do so.

They Call Me Mister Fast
Q I recently purchased a naturally aspirated ‘87 MK1 MR2; they seem to be rare and not very popular in the street scene. My main concern is: where should I begin with the build? I’ve owned several Hondas but I really want to make my MR2 stand out and perform well power-wise. I love the magazine; keep up the good work!
Bobby Gordon
Fairmont, WV

A Whenever you take on a used car for a project, one of the first things we always recommend is a thorough inspection of the car so that you’re aware of what condition it’s in and how well it was maintained. Always make sure that everything is in good working order; check to see that all fluids are clean and at proper levels (and change as needed); and inspect the brakes and suspension to see if the car needs a tune-up or any repair work. This will also help you determine which direction you should go to for your mods. If your brakes are shot, you shouldn’t be looking at a new muffler first; or if your car is idling funny then that needs to be fixed before you look for wheels. Once you assess the condition of your car, then that will help you find that route for your modifications.

Switch ECUs or No?
Q I have a ‘78 Toyota Celica and doing the swap from a 20R to a 22RE. I used the 22RTE rebuild kit, using the 22RTE turbo and manifold, but I’m having trouble with the ECU. I’m not sure if the stock ECU from the 22RE can be used with the 22RTE turbo? I heard I might have to use MegaSquirt but before I go and buy an expensive aftermarket ECU, can you tell me if I can just use the stock 22RE ECU? Or, if there’s a less expensive option—I’m open to suggestions!
Peter Velasquez
Via e-mail

A It is highly recommended that you use the turbo ECU if you are trying to do a turbo conversion. Reason being: how does the car know to give more fuel and adjust timing in the correct circumstances if the ECU you use is from the normally-aspirated (non-turbo) model? It would “think” your car is non-turbo. If you are doing any other upgrades to the turbo conversion like intake, downpipe, exhaust, or intercooler, basically anything aftermarket—it is also recommended that you use an aftermarket ECU so that it can be tuned to work in conjunction with the additional modifications. There is no easy way around engine management and it’s very essential as engine tuning is one of the most important factors to making sure your car runs well. It is basically the glue that holds everything together and makes all the parts work in conjunction with each other.

Good for KA and SR?
Q I drive a ‘92 240SX daily and I’m planning on doing a SR swap by the end of this year. I know I’ll have to upgrade the fuel pump (planning on using a Walbro 255L/hr); if I change it now, will it be bad for my stock KA?
Brian Sandoval
Via e-mail

A You can change the fuel pump now/ahead of time to get it out of the way or as a precautionary measure. The vehicle may run a bit rich due to the fact that the factory pump is older and may be a bit worn. Since the car is 20 years old, it would also be a good time to check the inlet and return lines that route the fuel to and from the motor. It is very common for the rubber hoses that run between the fuel pump assembly and the hard lines that run under the car to crack and become brittle. It would also be a good time to change your fuel filter to a Z32 unit (larger, more flow) in preparation for your upcoming motor swap. Hint: while you’re at it, get a new fuel tank gasket and have it handy when you swap your fuel pump because when you remove the fuel pump assembly, the gasket seal on the fuel tank deforms and it becomes that much harder to put everything back together.

Crank That SR Boy
I’m mid-way through my project 240SX and ran into a problem. I decided to go SR20DET instead of KA-T because I found what I thought to be a good deal on an SR. I tore it down and found that my crank was pretty much done, a main bearing failure that somehow caused a crack on the 5th main journal. So much for a “built” SR. But my question is: will a crankshaft from a FWD SR work in a RWD SR?
Sean Callahan
Newark Valley, NY

A That is a good question. Since we have never encountered this before we asked a few SR20 gurus that we knew. When we have a SR20 issue we can’t solve, we ask Gary Narusawa (OMG) from Project Car Mag and Marcos Vargas from SR20Store, and this is what they said. The FWD and RWD SR20s are very similar in design and construction with minor differences. With the exception of the Pulsar GTi-R crank, you can use any of the FWD SR20 cranks, even the USDM NA one. Of course, when you do something like this, make sure your engine builder checks everything to be sure that it is compatible and will work with your “hybrid” build. If you need a good reliable source for parts and helpful information, contact Marcos Vargas at the SR20Store (sr20store.com); he is the ultimate SR20 guru.