bbmac

I have done a search and haven't been able to find what I am looking for.

to start off I will say what I believe to be correct and I would like to know if I am wrong.

Swapping a 13b into a gsl-se is quite easy due to the fact that they already have mounts for a 13b. my question is:

If you own a first gen rx-7 equipped with a 12a and got your hands on some gsl-se motor mounts would a 13b be a straight bolt in(aside from wiring and the obvious) or does the location of where the gsl-se's motor mounts are on the car differ from the 12a's?????

Any help woul dbe great

Bolox

iirc, the 12a has engine mounts on the front of the engine, and the 13B has them underneith the engine..

or i might be on drugs..

-Cheers

wwilliam54

the mounts are the same, but the crossmember is different to accomidate that the 13b is a little longer

rhinor61

Are you talking about installing a '86 or later 13b into a 1st gen car with a 12a?

I am not clear here on what you are trying to do?

John

Metallic_rock

Oh, my God.... This has been covered extensively in the 1st gen section.


To install ANY 13b aside from a Renesis in a 12a 1st gen, you need to install the GSL-SE oil pan, front cover and front engine mount. It will drop right in. Now, the wiring and everything else is another matter.

cosmicbang

No, not exactly true. If the 13B in question originally used the front cover to mount it in the chassis, you will not need to exchange the cover for one from a GSL-SE.

Jeff20B

iTrader: (13)

Oh no! You're forgetting the GSL-SE's subframe has the motor mounts further forward. It uses the same front cover mount as 12As.

peejay

OMG he got something right...

The way you get around this is to re-form the mount plate (combination of bending and ovalling holes) so that the front is about 20mm further forwards, to accomodate the 20mm longer engine.

OR you could relocate the transmission backwards instead... but this would probably need a modified oil pan and definitely a shorter driveshaft... especially if you also shorten the rear suspension links so make the wheelbase a little shorter and more rear-biased. (Not that I'm considering that or anything )

peejay

And the same motor mount bracket.

However, as soon as I get a junk crossmember to play with, I might be coming out with a line of engine mounts that are A: superior to factory and B: can be used universally - 12A in 12A car, 13B in 13B car, 13B in 12A car. Probably not 12A in 13B car, but we'll see if that can be accomodated or not.

wwilliam54

i thought about making a mount that drops the engine 2" and back 1"
it would be made from kevlar, but i havent gotten motivation to try it yet, and im not sure that kevlar would hold for all that long

cosmicbang

Why bend it? I have always just extended the mount with extra steel on the ends to make it 20mm longer. It seems the easiest and most straightforward way to go about it, and guarantees that the geometry will be correct. Someone said they just flattened the thing and it lined up, but unless I could model it first to verify it is exact, I would not bend it at all.

peejay

Well, if you can weld, that'd be the way to do it.

See my *other* thought was to just shift the subframe forwards 20mm. That way you can get more positive caster, *and* get the front wheels 20-25mm more forwards, getting more weight off the front end *and* increasing the Ackerman angle, since you'd be putting a forwards angle on the tie rods. Where's the downside? (besides having to trim the fenders, I mean)

cosmicbang

I like the idea of just dropping in an FC subframe. Too bad we didn't think of that 18 years ago.

Jeff20B

iTrader: (13)

Is that the correct terminology? I call it the front cover mount. What is the prefered uh forum name for it? You know, like how the metering oil pump/MOP is called an OMP here and stuff.

Will your new motor mount bracket be a modular type of thing? Or just have a flattened slotted area so as not to allow the oil pan to hit the motor mounts?

cosmicbang

For clarity I refer to said part as the "bracket." In this photo, the bracket was extended 20mm by welding additional steel stock to the ends. A new hole was drilled 20mm behind the slot, approximately where the original bracket ended. You can see the original slot in the picture. This bracket can now be used interchangeably for either a 12A or 13B engine. [This was not a goal so much as a convenient side effect. On the other hand, the method of bending the bracket would render it unusable with a 12A.] As you can see the lower corner is ground off to clear the oil pan. Grinding is only needed on this (spark plug side) side of the engine. The other side has sufficient clearance. This particular bracket was successfully used "as-is" for many years. One could add additional reinforcement with another layer of steel, but it is probably unnecessary.

bbmac

thanks guys . to clarify for john: I was thinking of taking and 83 rx-7 with of course a 12a and putting a 13b. now I was under the understanding that the difference between my car and a gsl-se was the motor mounts(and of course the ngine etc.) and figured that the mounting points on the frame were the same for the gslase's motor mounts as my 12a's.

now to put two and two together I was thinking if the above was true I would simply get gsl-se motor mounts and then bolt the engine in. but have been corrected..... Ithink????

REVHED

Correct.

Villision_Motorsports

what about the oil pan thing nobody finished that for me also where can I find information on what transmission to use in the first gen with the TII swap done can I swap the TII tranny as well and are there any problems with mounting?

Thanx
Mike

wwilliam54

use a gsl-se oil pan

jorx81@aol.com

iTrader: (6)

I can make quality mounts like the one pictured above if anyone is interested.
Pics avail.

cosmicbang

If you can't locate a gsl-se oil pan, it is also sometimes possible to modify other 13B pans to fit.

rhinor61

What???

peejay

If you are keeping the transmission in the same place (gaining the extra 20mm by going with a modified bracket or a -SE crossmember) then you use the -SE oil pan.

If you are shifting the whole drivetrain rearwards, you're on your own.

I'm contemplating modifying an oil pan so I can get the engine lower for intake manifold clearance. Shouldn't be too hard, just a nitch here, notch there, zap zap with the MIG and thoroughly paint the inside to prevent any possible leaks.

cosmicbang

It is very simple. Just take the pan off, heat it up red hot with a torch, and work it into the desired shape with hammer, etc. (in the past GSL-SE oil pans were not always available and needed to improvise.)

jorx81@aol.com

iTrader: (6)

I've stretched a 12a pan also. if you have the resources.