1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Chronicles Of 12A to 2nd gen 13B SWAP

Thread Tools
 
Search this Thread
 
Old 01-30-05, 06:52 PM
  #1  
Rotartist

Thread Starter
iTrader: (13)
 
RRTEC's Avatar
 
Join Date: Sep 2003
Location: Spring Hill TN 37174
Posts: 7,252
Likes: 0
Received 2 Likes on 2 Posts
Chronicles Of 12A to 2nd gen 13B SWAP

I have posted several seperate post involving my 13B N/A swap into my 1985 GS. I have decided to consolodate them into one ongoing post untill I finish my project. So I am going to stat from the begining.

The car started life as a 12A powered base model, I bought off ebay with a parts car for $143 about 1 year ago. The car was fairly straight but after further inspection the rear rotor had shed an apex seal. I let it sit untill one day a buddy bought a wrecked FC and I couldn't resist. I decided contrary to popular vote to keep the car EFI (more on that later)

I gathered all the parts needed for the install, the parts car (87 se) had the motor, ecu, EFI, wiring harness, coils, ect.

I bought the GSL-SE oil pan, and modified the motor mounts (as pictured) that were on the 12A originaly. I had to use the 12A oil pickup and I also used the 12A front cover (to hold the motor mounts). *note* you also have to use the 12A OMP if you are going to use the front cover from a 12A....

For this application I am using a 12A transmission so no fabbing will be needed to get the tranny to bolt into place (as a 2nd gen 13b requires custom mounts) I also retained the 12A driveshaft.

I will discuss the wiring in another post in this thread later.. Anyways here are the pictures of the motor mount modification, the motor in the parts car and then the motor in my 7.. To pull the motor and simplify everything I pulled the wiring harness through the firewall, and unbolted all the sensors and layed them on the block eliminating any confusion.. Stay tuned progess updates will follow.
Attached Thumbnails Chronicles Of 12A to 2nd gen 13B SWAP-brace2.jpg   Chronicles Of 12A to 2nd gen 13B SWAP-disaster-063.jpg   Chronicles Of 12A to 2nd gen 13B SWAP-disaster-064.jpg   Chronicles Of 12A to 2nd gen 13B SWAP-disaster-065.jpg  
Old 01-30-05, 07:02 PM
  #2  
Go Hawks!

iTrader: (1)
 
64mgb's Avatar
 
Join Date: May 2004
Location: Cedar Rapids, Iowa
Posts: 1,933
Likes: 0
Received 0 Likes on 0 Posts
I like this thread. I'm doing a similar conversion. 13B from an 89-91 non turbo into an 85 GS. I bought the front motor mount plate from MaxdaTrix. A lot cheaper to modify a 12A mount, but since this is my first I didn't know what is required. Also, I'm going with a Racing Beat Holley carb and intake, just to make it simpler. I have my motor pieces (rotors, stationary gears, e-shaft) at the machine shop now, and hope to start rebuilding in the next 2 weeks or so.

Keep posting pics...I will also if there is interest.

Rich
Old 01-30-05, 07:12 PM
  #3  
Wassup!!

 
Rotor13B's Avatar
 
Join Date: Jul 2001
Location: Longmont Co.
Posts: 1,081
Likes: 0
Received 1 Like on 1 Post
Won't the computer throw a code because your not using the electric omp?
Old 01-30-05, 07:17 PM
  #4  
Rotartist

Thread Starter
iTrader: (13)
 
RRTEC's Avatar
 
Join Date: Sep 2003
Location: Spring Hill TN 37174
Posts: 7,252
Likes: 0
Received 2 Likes on 2 Posts
My OMP is mechanical, as is the 13B one... The 89-91 Rx-7's had the electric OMP's if I am not mistaken...

Last edited by RRTEC; 01-30-05 at 07:30 PM.
Old 01-30-05, 07:18 PM
  #5  
Go Hawks!

iTrader: (1)
 
64mgb's Avatar
 
Join Date: May 2004
Location: Cedar Rapids, Iowa
Posts: 1,933
Likes: 0
Received 0 Likes on 0 Posts
I was told that you had to hang a 13B OMP off the side of the motor to keep the ECU happy if you are sticking with the EFI.
Old 01-30-05, 07:21 PM
  #6  
Go Hawks!

iTrader: (1)
 
64mgb's Avatar
 
Join Date: May 2004
Location: Cedar Rapids, Iowa
Posts: 1,933
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by RRTEC
My OMP is mechanical, as is the 13B one... The 89-91 Rx-7's had the electric OMP's if I am not mistaken...
Yea, that's correct...my response would only pertain to the 89-91 13B...
Old 01-30-05, 08:33 PM
  #7  
Wassup!!

 
Rotor13B's Avatar
 
Join Date: Jul 2001
Location: Longmont Co.
Posts: 1,081
Likes: 0
Received 1 Like on 1 Post
Originally Posted by RRTEC
My OMP is mechanical, as is the 13B one... The 89-91 Rx-7's had the electric OMP's if I am not mistaken...
Gotcha
Old 01-30-05, 09:55 PM
  #8  
Rotartist

Thread Starter
iTrader: (13)
 
RRTEC's Avatar
 
Join Date: Sep 2003
Location: Spring Hill TN 37174
Posts: 7,252
Likes: 0
Received 2 Likes on 2 Posts
This will be good, everyone ask any questions you want, they can all get answered in one thread and this will be like a growing 13B install "bible" for those doing the swap..

1st question answered 86-88 N/A 13B's have a mechanical omp...BUT if you are using a 12A front cover you must use a 12A omp.. 89-91's have an electric OMP, so you will have to rig it so you don't show an error code.

NEXT!
Old 01-30-05, 09:59 PM
  #9  
Full Member

 
rx7kidd315's Avatar
 
Join Date: Apr 2003
Location: earth
Posts: 58
Likes: 0
Received 0 Likes on 0 Posts
this maybe a dumb question but what is a omp?
Old 01-30-05, 10:15 PM
  #10  
Leaking oil like crazy!

iTrader: (1)
 
1stgen4life's Avatar
 
Join Date: Sep 2003
Location: Utah
Posts: 698
Likes: 0
Received 0 Likes on 0 Posts
Oil Metering Pump. Provides oil to engine internals. Injected into fuel-air mixture. SEARCH!
Old 01-30-05, 10:22 PM
  #11  
Full Member

 
rx7kidd315's Avatar
 
Join Date: Apr 2003
Location: earth
Posts: 58
Likes: 0
Received 0 Likes on 0 Posts
sorry
Old 01-30-05, 10:36 PM
  #12  
Leaking oil like crazy!

iTrader: (1)
 
1stgen4life's Avatar
 
Join Date: Sep 2003
Location: Utah
Posts: 698
Likes: 0
Received 0 Likes on 0 Posts
NP, your here to learn. There are a lot of questions that have been asked, so sometimes you can find stuff you need by just searching so you are encouraged to try that first. Glad to help though.
Old 01-31-05, 06:16 AM
  #13  
RX-7 Alumni

 
Rex4Life's Avatar
 
Join Date: Oct 2002
Location: Spacecenter Houston
Posts: 1,140
Likes: 0
Received 1 Like on 1 Post
Originally Posted by RRTEC
1st question answered 86-88 N/A 13B's have a mechanical omp...BUT if you are using a 12A front cover you must use a 12A omp.. 89-91's have an electric OMP, so you will have to rig it so you don't show an error code.
Not sure the 12a OMP will work, it only has two output lines where as the 13b OMPs have four. I think the GSL-SE OMP can be made to work with the S4/S5 setup, but then you need the SE front cover.

Premix is always an option also.

Scott

p.s. Isn't there another thread like this somewhere??? jk
Old 01-31-05, 06:35 AM
  #14  
Savanna Rx-7

 
kenn_chan's Avatar
 
Join Date: Jun 2004
Location: yokosuka japan
Posts: 1,577
Received 12 Likes on 7 Posts
try this out

Originally Posted by Rex4Life
Not sure the 12a OMP will work, it only has two output lines where as the 13b OMPs have four. I think the GSL-SE OMP can be made to work with the S4/S5 setup, but then you need the SE front cover.

Premix is always an option also.

Scott

p.s. Isn't there another thread like this somewhere??? jk

Take the RA OMP adapter (for electronic OMP) , and have the inner face remachined to match the 12a cover, or make a new adapter from scratch that matches between the two. any machine shop could fab this up, it might cost you a hundredor so, but ya want to play ya gotta pay.

kenn
Old 01-31-05, 06:50 AM
  #15  
HEAVY METAL THUNDER

 
rotary emotions's Avatar
 
Join Date: Oct 2002
Location: Elsenborn, Belgian Eifel
Posts: 3,864
Likes: 0
Received 0 Likes on 0 Posts
nah, just go easy: splice the lines from a 12A OMP. I did it that way, it's really easy. The 13B engine doesn't need more oil or something, it just uses 4 lines instead of two. So splicing the 12A lines is ok. Or indeed, go with a GSL-SE front cover.
Something about that transmission though: an FC NA tranny is no different then the one on your 12A. All what's different is the mounting bracket. So what you can do is take the brackets (the silent block too) from one to the other, and there you go. 12A shaft will still work. A TII box is the one that'll need fabbing.
Old 01-31-05, 11:21 AM
  #16  
Rotartist

Thread Starter
iTrader: (13)
 
RRTEC's Avatar
 
Join Date: Sep 2003
Location: Spring Hill TN 37174
Posts: 7,252
Likes: 0
Received 2 Likes on 2 Posts
I understand the Non-turbo Tranny will work, but my main reason for using the 12A is for the hair difference in acceleration, the gearing on the 12A tranny is set up a little better for autocrossing.

As for the OMP I am going to use y connectors and just splice the two hoses into one, I will also be premixing MMo as I always premix aswell as a precaution anyways.
Old 01-31-05, 11:36 AM
  #17  
Rotoholic Moderookie

iTrader: (4)
 
vipernicus42's Avatar
 
Join Date: May 2002
Location: Ottawa, Soviet Canuckistan
Posts: 5,962
Received 29 Likes on 24 Posts
What are you doing for Fuel?

The GS 12a originally came with a carb, and IIRC the pump for the S4 is in-tank. Have you decided what fuel setup you're using.

And I know you said you'd talk about wiring later, but what's the gist of what you had to do to get it hooked up?

Did you manage to salvage the rad out of that wreck, or are you using the 12a rad? In either case, what did you have to do to mod it up (mod the S4 rad to fit the 85's mounts, or mod the tubes to fit the 12a rad to the engine)?

More questions as I think of them
Jon
Old 01-31-05, 12:03 PM
  #18  
Rotartist

Thread Starter
iTrader: (13)
 
RRTEC's Avatar
 
Join Date: Sep 2003
Location: Spring Hill TN 37174
Posts: 7,252
Likes: 0
Received 2 Likes on 2 Posts
Great questions....

For starters I am on the fence right now about the fuel pump, I am building this car on a budget and am trying to take the "Cheapest" route I can to prove you don't have to have a lot of money tied up in a competitive track car or daily driver... So far the total is as follows.

$143 purchase price (2 cars)
$60 gas to pick both up
$55 Oil Pan
$179 for clutch (not needed but wanted fresh other one was fine)
$300 for wrecked FC with motor
$120 for tune-up items

Durring the strip down process I sold lots of Rx-7 parts on the forum, to many of you probably.. totaling around $500.

So currently I have
$857 in total purchases
-$500 in parts for the cars
= $357 in the car right now

It still needs paint, springs and a set of 14" rims to fit the race tires my dad donated, firegslse and I are working out a deal on some adjustables and it'll be done.

For well under $1000 I will have a 13B powered 12A car.

I am thinking of a masters univeral 45psi fuel pump from autozone (not currently avail but the website has a listing) meant for external inline usage. If not that I will probably go holley or something similar.

I am also going to attemp something different then I have seen so far as far as the wiring goes. Most people cut and splice the wiring to work... I am going to attempt to retain Both the FC wiring harnesses, instead of cutting and splicing ECU pinouts I will rewire the lights ECT, on my car instead, by doing this I am hoping to eliminate the problems that occur from messing with the ecu wiring. I am planning on using the idiot cluster and lots of the other parts that some people eliminate when sawpping.

I am retaining the 3 core rad that came in my car along with the front mount oil cooler. It is actually a superior rad. I had a spare FC rad but really like the 12A 3 core. I will be using an electric fan and pushing the rad forward a few inches.

Thanks for the question and keep them comming.

Last edited by RRTEC; 01-31-05 at 12:05 PM.
Old 01-31-05, 01:20 PM
  #19  
Absolute Power is Awesome

 
purple82's Avatar
 
Join Date: Mar 2001
Location: Issaquah, WA
Posts: 1,972
Received 5 Likes on 5 Posts
Originally Posted by RRTEC
I am thinking of a masters univeral 45psi fuel pump from autozone (not currently avail but the website has a listing) meant for external inline usage. If not that I will probably go holley or something similar.
I used a Bosch fuel pump from a Porsche 944, seems to work fine.
Old 01-31-05, 01:23 PM
  #20  
KARATE EXPLOSION

iTrader: (1)
 
cpt_gloval's Avatar
 
Join Date: Aug 2001
Location: Deadmonds, WA
Posts: 2,991
Received 33 Likes on 19 Posts
i'm going to be doing a swap like this soon (S4 13b into GSL-SE). assuming i'm just going to premix, is there a OMP blockoff i'll need and if so, can anyone let me know where to get it? what about blocking off the lines and fittings for it?
Old 01-31-05, 01:31 PM
  #21  
Rotartist

Thread Starter
iTrader: (13)
 
RRTEC's Avatar
 
Join Date: Sep 2003
Location: Spring Hill TN 37174
Posts: 7,252
Likes: 0
Received 2 Likes on 2 Posts
Lots of people on the forum have sold them, I made one for my holley setup, it is pretty easy...

Why would you block it off when your gsl-se OMP will work just fine? Premixing is fine I do it but the extra protection of the OMP is a nice insurance policy. Consider keeping it if at all possible..
Old 01-31-05, 01:36 PM
  #22  
Blew my 3rd one 12/8/08

iTrader: (2)
 
Unsupa's Avatar
 
Join Date: Jun 2003
Location: Inman SC
Posts: 821
Likes: 0
Received 0 Likes on 0 Posts
did you get new gaskets for the front cover/ oil pan or did you make your own?

i'd love to do this swap... just can't seem to find a motor for the SE....

Last edited by Unsupa; 01-31-05 at 01:48 PM.
Old 02-01-05, 02:06 AM
  #23  
Rotartist

Thread Starter
iTrader: (13)
 
RRTEC's Avatar
 
Join Date: Sep 2003
Location: Spring Hill TN 37174
Posts: 7,252
Likes: 0
Received 2 Likes on 2 Posts
I used Ultra blue- it works great, I have never had problems in the past... The ultra black looks better (finished product) but the ultra blue is a little tackier ( in the good sticky way)

I broke down and bought a sandblaster today....... Check out my first peice. It's my thermostat housing.. what do you think.. I am using the 12A housing instead.. It will simplify the radiator install. Sandblasted with MGO then wire brushed then Clear coated 5 times with high temp clear....
Attached Thumbnails Chronicles Of 12A to 2nd gen 13B SWAP-disaster-068.jpg  
Old 02-01-05, 07:28 AM
  #24  
Go Hawks!

iTrader: (1)
 
64mgb's Avatar
 
Join Date: May 2004
Location: Cedar Rapids, Iowa
Posts: 1,933
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by RRTEC
I used Ultra blue- it works great, I have never had problems in the past... The ultra black looks better (finished product) but the ultra blue is a little tackier ( in the good sticky way)

I broke down and bought a sandblaster today....... Check out my first peice. It's my thermostat housing.. what do you think.. I am using the 12A housing instead.. It will simplify the radiator install. Sandblasted with MGO then wire brushed then Clear coated 5 times with high temp clear....
Sandblasting is great isn't it? The only problem I have with it is the mess. I built a blasting box and it doesn't seal very well, so I have to sandblast outside to avoid the mess.
Old 02-01-05, 01:41 PM
  #25  
Rotartist

Thread Starter
iTrader: (13)
 
RRTEC's Avatar
 
Join Date: Sep 2003
Location: Spring Hill TN 37174
Posts: 7,252
Likes: 0
Received 2 Likes on 2 Posts
Fuel has been decided! I am in the market for a gsl-se fuel pump, it should flow pleanty for a stock setup. I can get a new one with a lifetime warrantee for $92.00 from autozone, so if anyone has one for sale cheaper let me know.


Quick Reply: Chronicles Of 12A to 2nd gen 13B SWAP



All times are GMT -5. The time now is 01:53 PM.