abeomid

Ok per request I posted this up without the steering column section as it won't be ready for another month or so.

Just a warning that I don't take any responsibilities in case anything happens to you, your dog, or your neighbours for attempting this conversion.

Please right click and save as:
http://www.bcrx7.com/swap.pdf

Any questions or concerns can be send to me at: omid@bcrx7.com

Cheers,
Omid

rotarygod

iTrader: (1)

Cool writeup. I wish I had saved the front end of my 2nd gen before I parted it out. My GSL-SE would love me for it.

How is the engine mounted? FC motor mounts or FB motor mounts?

It would also be cool to see how you improvised the steering.

Gregs

any plans for an fc IRS rear swap???
-greg

abeomid

well you can use either a FB or FC engine mount depending on the engine and your choice. I am presonally using a modified FB mount to lower my engine a tad bit. I don't exactly know what you mean by improvising for the steering, but there is something to remember here as the steering geometry is exactly same as 2nd gen as the height, control arms are exactly same place as the FC b/c everything is connected to the subframe.

As for IRS that was in the plans for this winter but I will be too busy to do so. Perhaps next year.

rotarygod

iTrader: (1)

So you can swap the entire 2nd gen steering system (column) and it all lines up perfectly? In other words the hole is in the same place on the firewall and the same distance as the 2nd gen so it is a direct swap? Cool to know if true. I only ask because you mentioned something about steering connection details coming soon in the writeup.

Since I'm not staring at my car right now, doesn't the 1st gen engine mount bolt onto the original subframe or are the mounts on the frame rails? I suppose I could answer that question myself after work. If you used the 2nd gen mounts, wouldn't the engine be sitting slightly farther back and down then with the 1st gen mounts?

abeomid

as for the steering, yes the column has to be built from using both first and 2nd gen columns and putting the together, only one weld is needed.

For engine mount, depending on where you decide to put the FC subframe, you might or might not need to modify it. Modifying the FB mount is easy anyways. I am sure by moving the subframe back or forth couple of inches, the original engine mount can be located. But when I did this conversion, I really did not care about the gine mount as for me moving the engine back was the first important thing.

One thing you gotta remmeber here as I said before and in the writeup, this is not a easy thing to do in your backyard with just wrenches. It involves welding and fabricating and for me there is no way I can explain every single small detail on here or write up.

abeomid

So has anybody bothered starting this...
Just wondering.
I will have the steering column write-up done shortly too.

abeomid

Apparently one of the members in Australia is attempting this swap in next couple of weeks, so for all of you RHD owners you can ask him soon any tips on that.

On top of that my steering column section will be done really soon (next couple of days).

Pele

iTrader: (28)

:

It's been a couple of days.

I recently have been presented an opportunity to purchase/be given a S4 GXL (4 pot brakes, 5 lug) complete subframe and steering column... (I'll probably resell the brakes and use 4 lug to match my GSL-SE rear... Unless I can figure a way to get 5 lug rears.)

Couple questions:

1.) How does the weight compare, Stock FB setup VS FB w/ FC subframe setup.

2.) You gain the FC engine mounts when putting this subframe in. Can the wheels be located in the center of the fender wells AND the engine mounts be located to allow the use of an FC engine at the same time, or will holes have to be ovaled?

3.) Can an FB camber/caster plate be used with the FC shock?

Pele

iTrader: (28)

Bump. The 5 lug/4 pot equipment was sold and I got a set of 4 lug single pot equipment in return. This effectively makes this swap's cost = $0. Power Rack too. 2.7 Lock to lock. 15.2:1 steering ratio.

Now, if I were to find another 5 lug/4 pot brake setup for cheap and install, would there be an easy way to get 5 lugs on the rear to match? I was thinking Guru's floating axle kit and have them custom drill the hubs.

Adapters kinda scare me. That, and they change the offset.

autopaul

I also just bought that setup, i have the whole thing bolted on already, but i need to find an fc steering column to finish up, the 4 holes for the subframe i drilled 1 inch further back from stock, and the wheels look perfectly centered, i love its so far, but i sill wondered, what people are doing about the unusually high ride hight using the stock fb springs and suspension perches,. i just cut a coil and a half off my springs and it looks good there, slightly lowered, but wanted to know what other people are doing

thekyl

HUmm I was looking the mod over and I didnt see the sway bar or anything on the sway bar are you planning on just not using the swaybar or just not gotten to that point yet?

Slammed_GSL

iTrader: (14)

My thought's as well, sway bar, is it connected to the subframe, if so then it's a non issue.

autopaul

nope its not, but its easy, just drill two holes after you line it up, and then put some 4 inch bolts through, or just weld on some nuts to the frame, not sure what im gonna do yet.
still wondering about the strut towers though, whether i should switch to fc ones, or just accept the high ride hight, and cut the springs. ill see how it goes,

Pele

iTrader: (28)

I thought the high ride height was solved by using a combination of the FC shock and the FB spring.

autopaul

unfortunately its not, i used the fb spring, and perches. and the fc shocks, it sat about 3 inches above stock ride hight

so i cut the springs down
\

Pele

iTrader: (28)

Abeomid says in the writeup that his sits at the stock height... Although he put the front bolts through the stock holes.

How does the change in caster affect handling and such?

jayroc

For 5 lug on the rear, there`s a company in Indiana that can make a set of axles for $300 that`ll fit the rear.
One of the guys who did the torsen swap got axles made there, IIRC, but he got 4x4.5. I`m sure they can hook something up. The axles are 27 spline like ford rangers, I believe.
http://www.moserengineering.com/

jayroc

At least, I THINK it was $300, it`s been awhile since I looked at it..

Pele

iTrader: (28)

I wonder how hard it'd be to replicate the Guru floating axle/hub kit stateside.

Hmmm... *ponder*

They're pushing US$1900 (converted from AUS$2500) which is steep unless I'm missing something but I'm not too keen on slidehammering axles.

abeomid

I will update the PDF soon. Keep the questions coming and I can add a FAQ section to it perhaps.

Cheers

Pele

iTrader: (28)

Well, some of my questions are more generic...

The ones that are specific to this swap are:

1.) Steering Column HOW-TO?

2.) Did you have ride height problems with the spring perch on the 2nd gen strut with 1st gen springs? How did you address them? (Cutting springs seems kinda ghetto.)

How bout coilovers? Which do you use? Ones made for the FC or FB?

Perhaps compare a FC strut with an FB strut. Where is the spring perch in relation to the bottom mount point where it attaches to the control arm and how long is the piston travel...

3.) How far back does the subframe have to go in order to get the FC engine mounts to line up with an engine provided that the FC engine is bolted to the stock 1st gen transmission.

4.) Any clearance issues with oil pans or such?

My more generic questions are how does the Caster change the handling. (As I know the location of the control arms and hence the ball joints is not in the same place as related to the top mount of the strut. Can undesireable caster be dialed out with camber/caster plates?

I'm working on my own options for large brakes and 5 lug in the rear, while still maintaining the RX-7 axle housing. So far, I dig the Guru kit with custom hubs except for the cost.

autopaul

i am just completeing my steering column portion of the project, so i can take some pics and do a writeup, if need be,

other than that my only question would be how other people adressed 12a engine mounts,

to answer Pele's q's about the oil pan, there are no clearance issues, not with a 12a anyways, but im sure a 12b wouldn't have any clearance issues iether, thats with the subfram 1" back from stock front mount bolt

grantmac

I used a ssecond subframe mounted between the framerails to mount my 12A, but it really wasn't a "nice" was of doing it. If you must stay with the 12A I'd look at modding the subframe to provide mounts. I used first gen springs (Eibachs, but they don't drop it much) with first gen strut tops and spring hats. They did require a fair amount of compression to fit and the rideheight is a little higher, but not much; then again I am running the subframe pretty far forward. So far I'm just driving with the stock FC front struts, but I will probably go with GC coilovers and Koni Yellows.
Grant

Pele

iTrader: (28)

Oh ****! I forgot that you've gotta remove the stock crossmember...

So the stock engine mounts won't work, hence no 12A and no GSL-SE 13B. You've GOTTA go 2nd gen engine, doncha. Hmmm.. More ponderance.