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

Jake's Build Thread- 85GS

Thread Tools
 
Search this Thread
 
Old 08-12-09 | 08:16 AM
  #26  
trochoid's Avatar
Old Fart Young at Heart
iTrader: (6)
 
Joined: Apr 2004
Posts: 15,145
Likes: 7
From: St Joe MO
Love the old British cars and the Subie SVX was sharp when they first came out. Good luck on your project. You've got a good start on it and it will be one of the few Cosmo RE swaps in a first gen. It will seem to be a daunting task at times, just keep plugging away at it.

I was at the Texas Motor Speedway in spring of 01 for the IRL race. I can still hear the noise to this day due to the way the track is built. One of the best races I've ever attended. Even came away with an autographed ball cap after a trip through the pits.
Old 08-12-09 | 03:15 PM
  #27  
Rotary Enthusiast
iTrader: (4)
 
Joined: Jan 2003
Posts: 766
Likes: 0
From: Bryan, TX
Your going to let me ride in this thing when you have it working right? (I am down the road in Bryan)

Very nice deal. Let me know if you need any help.
Old 08-12-09 | 06:31 PM
  #28  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
Come out to the track on any given race weekend and find me, I work on the track's Miatas. You're welcome to see the car. And another set of hands is always welcome.
Old 08-12-09 | 09:47 PM
  #29  
elwood's Avatar
Rotary Freak
iTrader: (1)
 
Joined: Mar 2003
Posts: 1,541
Likes: 25
From: https://t.me/pump_upp
+1 for the Subaru SVXs. I like the lines on those cars.
Old 08-14-09 | 05:56 PM
  #30  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
Elwood, this question is mostly for you, but I'm just asking in general.

With the FD transmission I'm going to be using, where are the transmission mounts and shifter location going to fall? How much fab work can I expect to do in that area?
Old 08-17-09 | 06:23 PM
  #31  
elwood's Avatar
Rotary Freak
iTrader: (1)
 
Joined: Mar 2003
Posts: 1,541
Likes: 25
From: https://t.me/pump_upp
I'll have to defer to the guys that have used an FD tranny to answer that one. If you have both an FB and FD, you can line up the bellhousing faces and measure the difference in the shifter locations -- same with the tranny mount.

I'm running an FC Turbo II tranny, and I relocated the shifter on mine so it fits through the console just like an FB shifter. I did it many, many years ago, but I swapped the shifter remote housing from the FB (which puts the shifer further forward in car), then I cut the control rod and re-drilled it for the roll pin so it would work. The whole thing turned out perfectly.

As for the tranny mount, I used the FC rear one. I welded up the existing body mount holes in the crossmember (4 of them on an FC), mated it up to the tranny, then re-drilled the crossmember holes in the correct fore-aft location. I had to replace all the bushings because FCs seem to eat them.
Old 08-28-09 | 02:20 AM
  #32  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
Made some progress today. Had a chance to pull the lovely lady into the shop and get some work done.

Here she is on the lift:



The muffler was not cooperating, so I let my friend Mr. Acetylene have a word.



Here's the hoist hooked up to the engine, and an action shot of Kyle.



It's free!



On the ground, and seperated:



Empty engine bay:



As it sits right now:



I'm tired. Long day of working on the school's car, working on my car, then celebrating at a friend's house for a few hours. I haven't been up this late in months.

And there's more work to be done tomorrow. Hopefully I'll be picking up that 13B tomorrow, so I'll tear into that and have more pretty pictures.
Old 08-28-09 | 10:08 AM
  #33  
mattreeve's Avatar
Senior Member

 
Joined: Sep 2003
Posts: 268
Likes: 0
From: Richmond, B.C
lookin good man keep it up.
Old 08-28-09 | 05:36 PM
  #34  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
Not a whole lot of progress today, but it was a monumental day. I finally got my hands on the motor and pulled it apart.



Cute little turbos, huh?



No thrusting, and the apex seals feel to be in good shape. Overall, the motor's in about as good of shape as I could have hoped for. It's missing a lot, but I got it for $300, so I think I came out ahead.

Now, it's time to do some research on modifying the turbos for non-sequential operation.
Old 09-02-09 | 11:07 AM
  #35  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
I need some help making a decision.

The motor feels like it's in good shape. It turns over cleanly, all the apex seals appear to be healthy and intact, at least from what I can see from the exhaust ports, and all the gaskets I've come across are in good shape.

Rebuild or not to rebuild? Part of me wants to tear the engine apart and replace all that needs it, in the name of being thorough, but that's going to be expensive. And I'm in college, so I don't exactly have money to be throwing around if I don't have to. The other half of me feels like it's not going to be cost-effective, if the motor passes all preliminary tests on the bench. Maybe I should just clean it up, throw it in the car, and make it run. It'll have a full performance rebuild at some point in the future after I graduate, but now I just want my baby to run.
Old 09-03-09 | 12:34 PM
  #36  
StricklyOldskool's Avatar
Senior Member

 
Joined: Aug 2005
Posts: 400
Likes: 0
From: Florida
I had the same decisions when installing my cosmo. I had it installed cause it was checked out by my builder. After a few pulls on the single turbo setup, it thru an apex seal in the front housing and had to pay to replace the front rotor housing and other parts it tore up. I would vote to rebuild the engine while its out of the car and slowly work on it as u progress on working on the rest of the car.

Be sure to locate a GSL-SE front cover and oil pan to mount the motor in there, or go with the RE-Speed steering rack and all u need is the front cover, can use the cosmo oil pan as is.
Are you going with a single turbo setup? What ECU u going to use?
Old 09-03-09 | 01:05 PM
  #37  
80's old school's Avatar
common sense prevails....

iTrader: (7)
 
Joined: Jul 2008
Posts: 1,669
Likes: 9
From: Chino and Lake Arrowhead Calif
Originally Posted by Unevolved
Come out to the track on any given race weekend and find me, I work on the track's Miatas. You're welcome to see the car. And another set of hands is always welcome.
I will...do they ever have track days where i can bring my Mazda and play???
Old 09-18-09 | 12:35 PM
  #38  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
Originally Posted by StricklyOldskool
I had the same decisions when installing my cosmo. I had it installed cause it was checked out by my builder. After a few pulls on the single turbo setup, it thru an apex seal in the front housing and had to pay to replace the front rotor housing and other parts it tore up. I would vote to rebuild the engine while its out of the car and slowly work on it as u progress on working on the rest of the car.

Be sure to locate a GSL-SE front cover and oil pan to mount the motor in there, or go with the RE-Speed steering rack and all u need is the front cover, can use the cosmo oil pan as is.
Are you going with a single turbo setup? What ECU u going to use?
Not sure I have the money to rebuild it right now, but we'll see. If I ever get the money, I won't hesitate to pull it out and rebuild it. I know that throws up the default red flag of "Do it right or don't do it at all" but I really need to be careful with how I spend my money on this project.

Originally Posted by 80's old school
I will...do they ever have track days where i can bring my Mazda and play???
Yes, but unfortunately unless you're a Blue group solo student or better, you have to do the driving school first. I'm sure you can imagine how well a truly open track day would work. Far too much buffoonery.

Slight update, I decided to purchase a garage for the car. She deserves better than sitting out in the weather all the time, and it'll be nice to not have to pack everything back up when I'm done working on her.



It's not huge, but it's enough. I can lock the car up and keep her out of the weather, and I have enough room to work.



There's enough room for me to walk around the car and open both doors, and room for a set of shelves and a workbench on the right side. There's also about 4 or 5 feet in front of the car. It's pretty much a one-man shop. But it's got electricity, so I'm happy.
Old 09-18-09 | 02:13 PM
  #39  
j9fd3s's Avatar
Moderator
iTrader: (3)
 
Joined: Mar 2001
Posts: 31,197
Likes: 2,825
From: https://www2.mazda.com/en/100th/
Originally Posted by Unevolved
I need some help making a decision.

The motor feels like it's in good shape. It turns over cleanly, all the apex seals appear to be healthy and intact, at least from what I can see from the exhaust ports, and all the gaskets I've come across are in good shape.

Rebuild or not to rebuild? Part of me wants to tear the engine apart and replace all that needs it, in the name of being thorough, but that's going to be expensive. And I'm in college, so I don't exactly have money to be throwing around if I don't have to. The other half of me feels like it's not going to be cost-effective, if the motor passes all preliminary tests on the bench. Maybe I should just clean it up, throw it in the car, and make it run. It'll have a full performance rebuild at some point in the future after I graduate, but now I just want my baby to run.
my feeling is that its a 20 year old motor (89-95), so if it was mine, i would pull it apart.

you just check all the seals and clearances and replace what's not in spec, that way you start with a decent engine and not a question mark.

plus its a good time to put the FD oil pressure regulator ($25) in, and upgrade to the FD corner seal springs if it isnt already.
Old 09-18-09 | 02:33 PM
  #40  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
How much would you estimate all that would cost?
Old 09-18-09 | 02:41 PM
  #41  
j9fd3s's Avatar
Moderator
iTrader: (3)
 
Joined: Mar 2001
Posts: 31,197
Likes: 2,825
From: https://www2.mazda.com/en/100th/
Originally Posted by Unevolved
How much would you estimate all that would cost?
gasket set is like $160, plus the oil orings ($80?) couple of seals, tube of goop, corner seal plugs, FD regulator.... it can be about $450-500
Old 09-18-09 | 06:30 PM
  #42  
elwood's Avatar
Rotary Freak
iTrader: (1)
 
Joined: Mar 2003
Posts: 1,541
Likes: 25
From: https://t.me/pump_upp
You are right that the price tag will increase substantially if you open up the motor. As soon as you see the parts and start doing some research, you'll be tempted to change a bunch of stuff:

- Rotor Housings (or at least exhaust sleeves) to get rid of the restrictive Cosmo exhaust sleeves
- Apex Seals to move to the RX-8 two piece design, which seems to be more robust
- Resurface the irons (if needed)
- FD oil press regulator (as already mentioned)
- RX-8 Stationary Gears (recommended for high HP)

I changed a bunch of stuff, but mostly because corrosion ate through the irons to the rotor chamber and I was forced to. If you're short on cash, I'd check compression -- if it's good, run it as is. You can always rebuild later if you need to.
Old 09-19-09 | 12:24 AM
  #43  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
Originally Posted by elwood
If you're short on cash, I'd check compression -- if it's good, run it as is. You can always rebuild later if you need to.
I think that's what I'm going to wind up doing, for the reasons you mentioned. If I open up that motor, I'll NEVER get finished. "Oh, while I've got it apart, might as well send the irons off to get ported and get some FD housings..." It will never end.
Old 09-19-09 | 02:41 PM
  #44  
Directfreak's Avatar
I can has a Hemi? Yes...
iTrader: (2)
 
Joined: Dec 2001
Posts: 9,371
Likes: 4
From: 3OH5
Originally Posted by elwood
If you're short on cash, I'd check compression -- if it's good, run it as is. You can always rebuild later if you need to.
I agree 100%. I ran my JDM engine for a full two years before I opened it up.
I opened up because the rear plate cracked when the pressure plate inverted itself while at the 1/4 mile track.
Old 09-19-09 | 07:42 PM
  #45  
elwood's Avatar
Rotary Freak
iTrader: (1)
 
Joined: Mar 2003
Posts: 1,541
Likes: 25
From: https://t.me/pump_upp
Rest of the Story?!?!?!

Originally Posted by Directfreak
I agree 100%. I ran my JDM engine for a full two years before I opened it up.
I opened up because the rear plate cracked when the pressure plate inverted itself while at the 1/4 mile track.
You can't just drop a teaser like that without any details. Come correct, and tell us the whole story
Old 09-20-09 | 09:18 AM
  #46  
Directfreak's Avatar
I can has a Hemi? Yes...
iTrader: (2)
 
Joined: Dec 2001
Posts: 9,371
Likes: 4
From: 3OH5
Originally Posted by elwood
You can't just drop a teaser like that without any details. Come correct, and tell us the whole story
Old news. The car ran a blow-thru setup back then.
https://www.rx7club.com/showthread.p...ghlight=kramer
Page 2 shows some of the carnage..
Old 09-21-09 | 01:21 PM
  #47  
elwood's Avatar
Rotary Freak
iTrader: (1)
 
Joined: Mar 2003
Posts: 1,541
Likes: 25
From: https://t.me/pump_upp
Wow! -- glad you weren't injured.
Old 09-23-09 | 12:02 AM
  #48  
z-beater's Avatar
REW'd FB
 
Joined: Dec 2004
Posts: 2,685
Likes: 0
From: WA
Sounds like you have a good start. I went the REW route, but for a little more information search my name. I created a thread some time back outlining the major obstacles of the build. Good luck.
Old 09-26-09 | 11:52 PM
  #49  
84gs_rx's Avatar
Full Member
 
Joined: Nov 2008
Posts: 109
Likes: 0
From: poulsbo
looks like the first british car was a rolls royce silvercloud, if im not mistaken beautiful car
Old 11-30-09 | 01:59 PM
  #50  
Unevolved's Avatar
Thread Starter
Function > Form

iTrader: (1)
 
Joined: Jun 2009
Posts: 330
Likes: 0
From: College Station, TX
This build is having a sort of identity crisis.

I'm a college student with marginal income, but a love for cars. Too much, at times. I sold my Civic for an F150 that's a parts hauler, and I therefore have nothing to drive drive. The RX7 hasn't had significant progress made in over two months, due both to time and money.

I'm starting to consider rebuilding the 12A and putting the -RE aside for a while. As much as I want to have a tire-shredding rotary right now, a moderately-powerful car I can drive sure beats the hell out of a super-boosted garage queen that doesn't run. Part of me is thinking seriously about rebuilding the 12A completely so it's drivable again, and start doing suspension, brakes, and wheels and tires so I can autocross it. Just sort of sit on the -RE swap for a little bit until I have the parts accumulated to do it all in one fell swoop. I love this car so much, it just breaks my heart for it to be sitting in a shop all the time when I could be driving it.

Everything on the car is in good shape, aside from the 12A, so it'd be a matter of rebuilding the engine, something I'd love to do, and putting it back in. From there I could drive it, autocross it, and actually enjoy the car. Power and uniqueness is awesome, but I'm not sure I can afford that right now.


Quick Reply: Jake's Build Thread- 85GS



All times are GMT -5. The time now is 10:26 AM.