rotaryguy481

iTrader: (-2)

Has anyone ever done one of these? if so what should I look forward to I have done an s4 na to s4 t2 swap and that's about it and that was pretty easy in a sense what should I expect is the ultimate question?

Alak

iTrader: (9)

You should expect it to deminish your bank balance hahaha. Lots of guys have done it. Lots of do it yourself custom work.

tuscanidream

iTrader: (6)

Eunos 13bre or 20brew? It came with two different engines.

Akagis_white_comet

iTrader: (4)

Gotta agree with the consensus overall, it will drain your bank account. I will attempt to cover all the issues you may encounter

Is this ambitious for a newer owner? Definitely
Will you learn from the experience? Absolutely
Would I personally recommend it? The answer to that is: How prepared are you to build your own solutions?
The ultimate question: What ECU will you be using?

Most of the questions you have can probably be answered by reading my build thread here:
https://www.rx7club.com/build-thread...tormas-888195/

Warning: Book ahead.

If you are considering a 13B-RE Conversion, I would highly recommend starting with Banzai Racing's mounts. This will make it much less frustrating getting everything lined up suitably than fabricating your own mounts from scratch as I did (and re-did later). I probably spent at least a month getting the first set of mounts close to useable, grinding them with a dremel every day, only to run out of adjustment room and have to make a second set to get them perfect. While I am very happy with how they turned out, I HIGHLY recommend using pre-fabricated mounts so you can get to the fun stuff sooner.

Engine Accessories: It is simplest to just swap over your existing S4NA parts. You'll either need to use a S5 water pump housing or modify the bottom hose barb neck to clear the 13B-RE's OMP. I do not have any firsthand experience with Banzai's mounts, so you may need to be creative with plumbing items such as the radiator. Depending on the WP Housing you use, you MAY be able to get away with using S5 hoses. However, these questions are best answered by Banzai Racing.

Intake & Exhaust: What are your plans for this? Keeping the Cosmo twin turbos? Swapping to FD twins? N/A? Single Turbo? The Cosmo intake elbow will not clear the S4's A/C & P/S accessory bracket, nor does the 20B's Y-pipe assembly clear the hood in stock form. Since these are made of Cast Aluminum, you'll have to tig weld them. Aaron Cake talks about this briefly in Part 23 of the 1976 Cosmo Restoration here:

There are some pre-made intake elbows available on ebay that fit both the Cosmo and FD throttle bodies, but I have heard they are of questionable quality and workmanship. Depending on the route you go, you may have some issues with routing the intercooler plumbing as well. I am not sure of the exact front-to-rear placement of the intake elbow on a 13B-RE, but you'll have to route it around the strut tower sheetmetal and Power Steering pump or A/C Compressor. I just happened to get lucky with my 20B-REW and had barely enough room to squeeze it between the P/S pump and fuse box. It is currently the long 'dryer duct' in my thread.

The Sequential Twin Turbo Control System on the 13B-RE and 20B-REW works identically compared to the FD. I go into extensive detail in my build thread, outlining the entire changeover from primary to twin turbo mode and provide a very detailed, easy to understand vacuum diagram. You may use it if you give me credit for it in your build.

ECU & Wiring: This depends on your decision regarding the turbo(s). The N390 Cosmo ECU (13B-RE) will NOT work without the Automatic Transmission Computer unless you are exceptionally good with falsifying its various signals, same goes with the 20B's NF01 ECU. A FD ECU could be made to work, but will require considerable wiring effort to blend suitably with the S4's stock wiring. The ECU connectors can be sourced from Tyco Electronics (TE Connectivity: Every Connection Counts - TE), but the rest may be rather difficult to track down. Check the 3rd Gen section for more information about them.

Sensors: Depends on your ECU choice. A FD ECU will require FD sensors, which may or may not be plug & play with a hybrid S4/13B-RE engine such as this. The Coolant Temperature sensor will thread right into the water pump housing, and I would imagine that the CAS would drop right in just as well (see the 3rd gen section to be certain).

Injectors & Ignition: Depends on ECU choice: If using a FD ECU, you'll need FD coils. As for injectors, you would need to find some 850cc high impedance injectors meant for a FC (for the 13B-RE Secondaries) to make the FD ECU be able to maintain a proper air/fuel ratio.

Overall, the FD ECU can be made to work if you are determined enough, but it limits your results far more than what you'd save compared to a standalone EMS such as the Haltech Platinum Sport 1000 or 2000. It is infinitely easier to tweak a few settings in the software than hope and pray that you can find a FD-specific sensor and adapt it to your build. One such example from my build is that I'm using the Coolant Temperature Sensor from a LS2 Corvette. It was far cheaper than both the FC/FD ones, can be found with its correct pigtail at any Autozone 24/7/365, threads right into the WP housing with no fuss (M12x1.5 thread pitch, same as stock) and Haltech's ECU Manager already has a calibration profile for it.

Same goes with the ignition coils, you can use any coil you want. I'm running D585 coils from a 6.0L Silverado.

You should spend some time in the Standalone Section of the forum, reading what Claudio RX7 and C.Ludwig have to say about the specific items you are looking info.

cambam3486

I have put a 13b-re into a s4 na. banzai mounts, haltech ps1k ecu and sensors, turbo2 drivetrain conversion, and a-spec single turbo setup. It took me about 4 years to get it all said and done cause after you buy one part you find something else you want or need to get it done. Im not going to try and talk you out of doing it but its not an affordable swap.

j9fd3s

iTrader: (3)

the 13B is really easy, you need the banzai mounts. since its a 13B you can use basically everything from the FC except the intake, so water pump/turbo/ecu/wiring/clutch/trans.

the S4 ecu will work, although a standalone might be better.

the stock throttle body elbow fits i think, or it will with some trimming.


the 20B gets harder. you can still run the Banzai mounts. you need to buy a light flywheel, but after that you can use a T2 clutch.

i've always used the 20B water pump (ive done 3 20B swaps), it needs a little fab work, as the radiator hose points the wrong way, it flips over. then we've always replaced the second thermostat bypass valve with a radiator cap, which is easy, but its fab work.

the stock 20B ecu is a HUGE undertaking, there is a lot of stuff that ran thru the body harness, and onto the passenger side fender, like the ignition. so if you don't get the harness, you must make it, and its a big job. i have driven down the street on the stock ECU, but a standalone is much easier.

the stock turbos fit the FC, the "Y" pipe needs to be shortened, as it won't clear the hood on the FC, you're on your own for intercoolers. so you need to fab pipes, which is easy.

the little downpipe on the stock turbo has a weird flange, we always had to have that made, which is kind of a pain. after that though the muffler shop just made a short pipe to hook to the RB center.

rotaryguy481

iTrader: (-2)

It will be the 13b for sure I would love a 20b but prob don't have the patience for that yet. I have the five lug conversion with the s4 t2 Rearend and half shafts the motor I'm getting will have the engine, tanny, ecu and haness will I need to get a different driveline

j9fd3s

iTrader: (3)

the tanny and ecu are doorstops. the harness can be useful. the pinout is different than anything else, I would move the pins around to use whatever ECU, you might just use it for connectors.

RotaryEvolution

iTrader: (30)

sure you can weld a cosmo front end to an FC back end if you have a chop saw and a welder.

j9fd3s

iTrader: (3)

OMG, someone needs to photoshop that!

rotaryguy481

iTrader: (-2)

LMAO!!!!! That would be funny as ****.

RotaryEvolution

iTrader: (30)

i did once see an FD that had 2 separate halves welded together. once the owner(s) found out about it i have no idea what they did with it, as it became un-sellable.

question is, which sunroof would you want: the Cosmo or the FC?

j9fd3s

iTrader: (3)

ive seen miatas like that..

RotaryEvolution

iTrader: (30)

sorry for the derail, it was the first thing that popped into my head when i read the title..

ben.farnath

Haha that'd be awesome be the rx equivalent of a nissan sil80

Sent from my GT-I9100 using RX7Club

Konnors7

I would love to see that photoshop it