I am looking to buy this 1989 gtu rx7
this is the mod list
ModList:
13B engine Street ported by Atkins rotary
Holley 650 4 barrel Racing beat kit with manifold
Racing Wires
MSD Digital 6
B&M short throw shifter
Racing Beat headers
Racing Beat Resonator
No cat
Apexi N1 true dual catback exhaust
Holley External fuel pump
How hard would it be to change over to direct injection from a carb? and is there anything else i would need to change?
here is a link the the car http://www.cardomain.com/ride/2112183

 

You will never be putting direct injection on your engine. Mazda haven't even done that yet (on a production engine).

If you mean regular ol' EFI, all you need to do is refit all the factory EFI parts. You'd need the complete intake manifold, TB, intake duct, wiring harness, all sensors, EFI fuel pump, etc.

Studying the FSM Fuel Systems chapter will show you all these parts and more. If you don't have the FSM, click here and download it in PDF format for free.

 

if you are talking about gasoline direct injection, why on earth would you want it, and yes, mazda has a production car with gasoline direct injection, mazdaspeed 3.. DISI motor, 2.4 liter turbo

 

I said his engine, i.e. a rotary.

 

No you didn't.

 

lol, yes he did? "...on your engine...", ie: a rotary

 

I ment the stock fuel injection system
How much would this conversion cost? and could a normal shop do this, or would i have to bring it to a rotary shop.
The person selling the car says the it needs a new carb or a carb tune. But if i could switch it back to the stock injection system i would rather do that

 

I just received an email from the seller.
he has all of the old fuel system.
Does anyone know a website or topic where it shows how to switch it over? and is it hard to do?

 

search for intake removal and such and you should be able to stumble through it in an afternoon with the help of a haynes manual or the FSM

 

Would this be hard to do by myself?
Also i do not work on cars often, and i am in no way experienced in this area, but i do have friends that do some of their own car work that could help me.

 

If you are not mechanically inclined I would say that this would be a fairly big project to take on by yourself. If everything is present and still operational then it is possible for you to do it on your own but if even one part is missing you might hit a brick wall if you don't know what you are doing.

IMO you should never take a rotary to a non rotary shop for anything to do with the engine... they simply don't know what their doing.

 

for what you need to do,you'll need the following:

lower and upper intake from the same series motor (S4)
not sure if the motor was converted to a 4-port set-up,if it has you'll need to change it as well.a factory matching wiring harness and same series ecu,fuel injectors,fuel rails.or go with some sort of standalone to control it.

depending on how the carb set-up was done and maybe the factory stuff is still there.it can be quite a bit of work.

 

does anyone have a website or something that shows step by step instructions on this? or anyone here do it before?

 

waste of time and money unless you are REALLY fiending for a project. just buy a car that hasn't been messed with--nonturbo 2nd gens aren't that expensive and there are some decent ones around if you're willing to drive a bit. What you are proposing is a lot of work for a 16 second car. Don't feel like you have to get this car because the body is in good shape and it's local.

if you do insist on doing this, here's how it would go. And I'm being serious here.

1. pull the motor

2. fine a good donor car and pull out everything in the engine bay--especially if you want to pass emissions.

3. install most of the stuff from the donor car on to the car you bought (just about everything except maybe the body electrical stuff like the windshield wiper motor)

4. reinstall motor

I mean, I guess you could do it with the motor in but it would probably be way easier to just put it on a stand given that you will have to tear the motor down.

 

how did you the carb swap

 

no one knows where i can find a step by step process for this? or one where they put on the carb and i can just do it reverse order?

 

I thought they made an injection throttle body for that manifold.

If you want efi, why dont you get that, and the stock injectors/fuel pump, and an ecu wiring harness and array of sensors, more power to be had that way. Though the stock ecu wouldnt work well with it and youd have one hell of a time getting the tps to work, might as well go standalone.

 

I havnt done anything to the car, since i dont own it.
I was planing on purchasing the car, but posted here to see how much of a hassle it is to convert it back to the original fuel injection. The seller says he has all of the stock fuel system and some still attached to the car.

 

Pretty easy.

 

Do you know where i can find a DIY on it or from the stock fuel system to a carb so i can just do it in reverse?

 

Where in PA you located?

 

The closest you will find are the installation/removal procedures for the various EFI components in the FSM/Haynes manuals.

If the wiring was not hacked, then all you will need to do is bolt on the EFI manifolds, swap the proper fuel pump back on, reconnect the wiring, reinstall the ECU and replace any missing parts.

However if you have to ask, this is perhaps not the best car for you to purchase. In almost all carb conversions I have seen, the original car has been HACKED to the point where either a major rewire or a replacement harness would be needed to restore the car. Keep in mind that most people perform a carb conversion because there is a preexisting problem with the car that they are unable to understand/fix and think that converting to carb is a suitable solution.