About 3 months ago i purchased a non running 1988 rx7 fc gxl with a s5 turbo II swap. It wasnt running so i got it dirt cheap. I did a compression test and saw that the rear rotor was healthy and the front had no compression at all.

I Pulled the motor and took it apart and found out that the front side seal was stuck and the front and center iron had a crack in the center. So i decided to go v8 i purchased a 5.0 and had everything i needed to swap it but the conversion kit. While i was waiting for the funds i thought of an idea..

So i have EVERYTHING for the Turbo II s5 all the bolt ons, so why couldn't i just purchase a running s4/s5 engine N/A and swap my turbo ****, like the lower and upper intake, injectors, turbo manifold and turbo?

I just want to know the risk im taking with seals in the n/a with doing this. I have read around a little bit and the n/a have higher compression? So if i boosted a n/a wouldnt it have a higher risk of blowing a seal?

Since the n/a has higher compression, if i boosted it wouldn't it make more power then a stock TII?

Little new to the rotary scene but i have the mechanical skills. Just looking for some advice thanks.

 

There is more then enough info on this. Searching the site may yield poor results since it is asked 35000 times a week. Maybe check the stickies and archives or use Google to search the site.

 

If your housings are good you could just buy the 2 irons you lost on the turbo engine.
Your compression on the non turbo rotors will be 9.4 for s4 and 9.7 for s5 with that being said remember your ecu will think they are turbo rotors with lower compression, so you will have to choose low boost, rtek chip or full standalone.
I dont really care for boosting on oem 3 piece seals some guys have had luck but they make 2 piece seals for a reason.
With all that you thought about doing a 5.0 swap and had parts for it. Imo (flame suit on ) its going to be cheaper to finish the 5.0 swap than to rebuild your turbo block or buy a well suitable na block. Searching is a little difficult due to the redundancy of the same question but since your new alot can be learned by reading. Happy motoring

 

For your first build I wouldn't really recommend doing a turbo/na build, there are many people who have had great results, but there are many others who will blow the engine up in the first week it's running.

Tuning needs to be much more precise, all supporting mods will need to be there , as detonation will be more likely due to running the higher compression, there will be alot more flow, but that comes with way more risks

Turbo engines with high compression rotors are a double edged sword, you will get more power from less boost etc, but you'll always be running closer to the edge of blowing your motor.

If you're still adamant in trying to do a turbo/na rebuild , there are plenty of resources on the site, you'll probably want to talk to someone that's got one that's running well.

 

know any one with a good running one cause i have a well running rebuilt na s5 drifting for 2 years now i wanna turbo it

 

Sell that **** and buy a TII.

 

High compression turbo motors can be very reliable...

However, the safety margin between reliable and disaster is greatly reduced.

You will need, at the very least, a more than adequate fuel system, an excellent wastegate scenario, and at bare minimum an rtek 2.1 to run the show.

The factory timing map is far too aggressive. The mixture is also of utmost importance because you have to be careful of running too rich as well as too lean. Too lean you'll detonate and too rich you'll misfire. Either way, your seals won't stand for it.

You will have to keep boost low.. 10psi is a good ceiling, 12 at the most if you want the motor to last. That being said, you would not need more boost pressure than that to make good power.

A high compression build is not ideal persay, but it is totally fine if you use your head (the one on top of your shoulders) and do your research. You'll have stronger torque low down, faster spool time, and plenty of top end to keep you entertained for sure.

Other than that.. quality 93 octane, gauges for exhaust gas temperature, and a good wideband will get you going. An efficient intercooler and/or water injection, plenty of patience and some mechanical sympathy will get you farther.

An NA gearbox and driveline will be fine, just don't go dumping the clutch..

That's the basic gist of it. Go for it bud

 

Here are the links from the FAQ:


Can I swap a Turbo engine/Jspec engine/13BT/etc into my Non Turbo?
Yes, check these links:
https://www.rx7club.com/2nd-gen-archive-72/s4-na-turbo-swap-details-813825/
Turbo Conversion
Rotary Resurrection home of the budget rebuild.
Rotary Resurrection home of the budget rebuild.

How do I add a turbo to my NA 13B?
What Turbo kits can I add onto my non turbo RX-7?
There are no longer kits formally made at the time of this post, however there are companies from time to time that do make available non turbo to Turbo Kits. Because most of these companies stop building the kits, or go out of business in short time, it is impossible to keep active links for them.

Most people that turbo a non turbo make their own kits:
Using the stock TII turbo, exhaust manifold with spacer, NA intakes and NA ECU:
The (Almost) Complete Guide To Turbocharging The Naturally Aspirated Second Generation RX-7
https://www.rx7club.com/forum/showth...threadid=88540

Aaron Cake's "Project Tina":
My RX-7: Project Tina

https://www.rx7club.com/forum/showth...threadid=88758
https://www.rx7club.com/forum/showth...hreadid=124232
http://users2.ev1.net/~ccoutts/turbo..._a_project.htm

Using the stock TII turbo, exhaust manifold, intakes, ECU:
http://forum.teamfc3s.org/showthread.php?t=37694

How to port match the TII lower intake to fit the 6 port block, allowing you to bolt on all stock TII turbo stuff to an NA engine:
Porting The 4 Port Turbo II Lower Intake To Fit The 6 Port NA Block

There are many ways to accomplish this from bare budget using stock TII parts with either a port matched TII lower intake or turbo manifold on a spacer. All the way to completely custom everything.

However if this is your first project, then the better method is to swap in the TII engine and appropriate accessories.

 

some people are just masochistic like this, others are ignorant in thinking they can convert the engine cheaper than selling it and buying the appropriate counterpart.

although as time goes on the turbo cars are getting more difficult to find.