My friend is planning on buying a 1st gen Rx7, and we plan to rebuild the engine, and either turbo the 12a, or swap to a 13b. But we have a few questions.
Could you use a bridgeport and then turbo the engine, or would you lose boost? If so, would you lose boost using a stage 2 street port?
What would be easier to do, port a 12a, and then turbo, or swap to a 13b, then port and turbo that?
And is twin or single turbo better for a rotary engine?

Thanks in advance for reading this and posting your opinions, and anwsers.

 

I think the good place to begin is with asking some question:
1)How much power do you want/need? <==dumb question
2) How much money do have?
3)How much spare time do you have?
4)Finaly How much money do you have?

My opinon is that porting a 12a isn't too difficult, porting the 13b is bout the same. Doing the 13b swap isn't bad so long as you have the right parts, i do luckily! Adding a turbo is not a good place to start. Do the porting for sure, get some good parts like exahust, intake, etc. Try the car out natuarly aspirated until you feel your ready to take on a project like adding a turbo.

course that is my 2cents. I bought a TII for $100 with the engine in the trunk in pieces and figured out how to put it back together... until I ran out of money.

I Love a tough project!

 

He wants upwards as much hp as possible, but I don't think he'll exceed 400-500 with the money he has.

Well, this sumemr my friend gets his college fund, so he's taking a little bit from that, so he's puting $20 000 or so canadian into the car.

We have August, so that's part time work, then mostly free time to work on it, plus if we don't get done we can do it at school.

The 13b would need a mounting kit right? And would you get significally more power from a 13b?

What would be best for a 400-500hp rx-7, 5pd maunal tranny, or an auto, and how hard/expensive is it to swap a auto to a 5pd?

Yea, I agree adding the turbo last is a good idea, and a TII for $100 would be nice, thanks very much for your help.

 

if your trying for that much hp then you definatly want to forget about 12a and concentrate on a 13b. I'm not 100% sure but in order to mount a 13b you need the front cover from a 12a or something like that. or maybe it was the SE cross member, or was it both... yea i'm not help

 

Go for a 13BT engine and tranny. Port, upgrade the turbo and efi, add a front mounted intercooler, upgrade the fuel system, clutch and flywheel. Do not forget suspension and brakes. Budget for $6-10,000 and you will end up with 400+rwhp and a 11 second 1/4 mile.

But as a starting point read the sticky on the transplant on this forum, then look at what other members have done, for example AJC13B and Mike 28P.

Another good source of ideas is look at what engine builders offer as a package. Rotorworx has an excellent description of their 12, 11 and 10 second packages which show the work you need to plan for.

You can go down the 12AT route but it will cost the same in the end, and you will have a slightly weaker engine and 10% less power.

 

Alright, thanks for all your help, we decided to go the engine and tranny swap route, thanks again.

 

You can Turbo Bridgeport. However, responsiveness is sluggish unless you are running large boost (18,20,25 PSI+) - then they become Monsters!

Good Luck.

 

series 4/5 13b engines will need the 12a front cover

 

By engine tranny swap... I figure you mean a 13bt engine and tranny?

 

yeah if u are gonna go turbo, you need to swap in a FC turbo tranny.

Your N/A one wont last very long.