I am thinking of undertaking a custome 12a turbo project and is was wondering if you all think it would be more cost effective to just drop a 13b turboII engine in my 84 gsl. Any words of wisdom and poeple or sites that come to mind to help me would be greatly appriciated.

 

There are at least four seperate routes. add a turbo to an existing 12A, try and find a Jspec 12AT, build a hybred 12A/13B, use a 13BT.

Starting with an existing 12A, this is relativly cheap if the engine is in good condition. Basically all you need to do is get the carb preped for a turbo then buy a turbo kit from somewhere like www.rotaryshack.com. Robert provides a good customer advice service. Then add an efficient header exhaust system

Going for a 12AT is expensive, if you can get one! You will need a new ecu and high pressure fuel system even to get the stock 142hp. For serious power, say 200+hp plus you will need a bigger turbo, and upgraded clutch with possibly two additional injectors. The costs are becoming greater than a 13BT of the same power but more reliability. There is little reference material to this approach used by several members, mainly in Australia where 12AT engines were imported to beef up the RX-3.

Build a hybred 12A with 13B centre to get a 4 injector efi; a great way to go if you have money, time, and mechanical skills. Very expensive but useful if you need/want to keep to a 12A engine capacity/weight with maximum power such as 300+hp. Little technical written on this approach.

Drop in a 13BT, you should be able to easily buy a good import motor from someone like Corksport or Rotaryshack. It is not a straight bolt-in task as you will be going efi. However, if you go to 'search' there are some very good threads on how to do it. Power will start at 180hp, then depending on how much money you want to spend then up to 500hp is available limited by various state rules for mofifying street cars. Emissions and noise regulations shouldbe checked.

What is best for you will depend on money available and expected use of the car.
Minimum budget for the first option is around $1500 increasing to say $8,000 for a really worked 13BT with the necessary suspension, and wheel/tire upgrades.

For general questions go 'search', if you run into specific difficulties ask a questionn as there are many experts on this forum with not too many conflicting views.

 

12A with 13B centre to get a 4 injector efi;

soo the 13b centerplate bolts to the 12a housing parts?
i mean no modifactions needed?

 

Yes. There was a brief write up about three ago by The Hitman for using the centre plate of a 6 port 13B, 4x550 13BT injectors and a IDA style throttle body. This produced 178rwhp in his NA mild street port. With a TO4 set-up on an engine, by I think Dalton or Roterworx, was elsewhere quoted as giving 250rwhp with a 13BT gear box.