12A vs GSL-SE front crossmember
#1
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12A vs GSL-SE front crossmember
Is it the cross member that has the engine mounting locations moved forward, or the engine bracket that has the holes moved backwards?
Have a GSL-SE with no engine or drivetrain. I'm pulling the cross member and wondering if it's useful.
Have a GSL-SE with no engine or drivetrain. I'm pulling the cross member and wondering if it's useful.
#2
The engine bracket is the same.
Having said that, I once noticed a 10mm difference between '84-'85 and '83. I was installing a rebuilt 12A in an '83 and happened to have a nice condition engine bracket from a known '84 12A. It was 10mm off. I grabbed the old rusty stock '83 bracket and it fit fine. I went ahead and cleaned up the rusty stock one, painted it, and used it. Everything lined up ok.
As for the GSL-SE, Mazda mounted the motor mounts further forward but it may only be 10mm, while the other 10mm was taken up by the bracket to equal the full 20mm of extra length of the 13B.
It makes sense for Mazda to do it this way in order to save some money. They changed the interior on the '84-'85 cars as well, and kept them the same whether 12A or 13B. Or maybe I just got a weird engine bracket or something? Somebody else who's actually compared a genuine GSL-SE bracket to an '84-'85 and '83 and older bracket would be more qualified to answer.
Having said that, I once noticed a 10mm difference between '84-'85 and '83. I was installing a rebuilt 12A in an '83 and happened to have a nice condition engine bracket from a known '84 12A. It was 10mm off. I grabbed the old rusty stock '83 bracket and it fit fine. I went ahead and cleaned up the rusty stock one, painted it, and used it. Everything lined up ok.
As for the GSL-SE, Mazda mounted the motor mounts further forward but it may only be 10mm, while the other 10mm was taken up by the bracket to equal the full 20mm of extra length of the 13B.
It makes sense for Mazda to do it this way in order to save some money. They changed the interior on the '84-'85 cars as well, and kept them the same whether 12A or 13B. Or maybe I just got a weird engine bracket or something? Somebody else who's actually compared a genuine GSL-SE bracket to an '84-'85 and '83 and older bracket would be more qualified to answer.
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#10
A. Using a GSL-SE crossmember and the original 12A mounting bar.
B. Using the 12A crossmember and a Racing Beat mounting bar.
C. Using the 12A crossmember with redrilled holes and the original mounting bar.
Hope this helps.
Last edited by XLR8; 08-01-07 at 12:04 PM.
#12
Originally Posted by Morey987
If you're using an se crossmember,,,, do you still need the 12 a face plate?
Wouldn/t that already be designed for the 13b?
Wouldn/t that already be designed for the 13b?
You can put a 12A front cover on any series 13B. The main reason it is so popular to use a GSL-SE front cover is for the use of the SE's Oil Metering Pump. The SE's pump has the 4 tubes where the 12A pump only has 2. You need the SE's pump to fit with the oil injection of the later factory intake manifolds.
If you plan to run premix, then there is no need to use an SE front cover, the 12a will work fine.
When you say "face plate", if you mean the mounting bar then, see my previous post.
Last edited by XLR8; 08-01-07 at 12:10 PM.
#13
The 12A front cover will still work fine even without premix. How so? Take a guess. Give up? The 4 line OMPs had less capacity per line than the 2 line 12A type. Just run the two line type into the rotor housings and block off the holes in the manifold. Easy as pie.
#14
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You still need a first gen front cover to mount any 13B into the first gen. Or ar the front mounting bolts (For the bracket) on all of the front covers?
#19
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You people are the shizzle!!! XlR8 and Jeff, you just won 50 forum bucks each. or a 30 minute session with the forum hooker, your choice.
Thanks, arranging to get the se cross member now.
Travis Nelson
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Travis Nelson
#20
I'm in the middle of installing a 13B in a 12A car with the RB bar and I seem to have run into trouble. I know the engine is scewed off to the driver's side in 1st gens, so it needs to be shifted that way a bit, but the oil pan lip hits the motor mount well before the engine is far enough over.
I heard you must grind a little off the motor mount. It's a new competition one, and I'd rather not grind on a brand new part, but it looks like I'll need to.
Am I doing anything wrong?
I heard you must grind a little off the motor mount. It's a new competition one, and I'd rather not grind on a brand new part, but it looks like I'll need to.
Am I doing anything wrong?
#21
I'm in the middle of installing a 13B in a 12A car with the RB bar and I seem to have run into trouble. I know the engine is scewed off to the driver's side in 1st gens, so it needs to be shifted that way a bit, but the oil pan lip hits the motor mount well before the engine is far enough over.
I heard you must grind a little off the motor mount. It's a new competition one, and I'd rather not grind on a brand new part, but it looks like I'll need to.
Am I doing anything wrong?
I heard you must grind a little off the motor mount. It's a new competition one, and I'd rather not grind on a brand new part, but it looks like I'll need to.
Am I doing anything wrong?
LH side: Retained the OEM lower cup, installed a stack of 3 fender washers under the mount.
RH side: Discarded the OEM lower cup.
This puts everything back to OEM locations and should correct your interference. BTW -- I needed to extend my crossmember slots upward a few mm on each side so the whole deal would sit properly.
#22
I'm in the middle of installing a 13B in a 12A car with the RB bar and I seem to have run into trouble. I know the engine is scewed off to the driver's side in 1st gens, so it needs to be shifted that way a bit, but the oil pan lip hits the motor mount well before the engine is far enough over.
I heard you must grind a little off the motor mount. It's a new competition one, and I'd rather not grind on a brand new part, but it looks like I'll need to.
Am I doing anything wrong?
I heard you must grind a little off the motor mount. It's a new competition one, and I'd rather not grind on a brand new part, but it looks like I'll need to.
Am I doing anything wrong?
If I knew this going in, I would of rather used the gslse crossmember with gslse front bracket. I recommend against the RB piece for this reason.
#23
Uh what?
I went to work with an open mind. Eyeballing where to grind the motormount and then grinding it was not a problem. Actually I used a hack saw and then ground a few mm to smooth it out (could be done with a file). Engine sits level. No need for fender washers and both cups are there.
The only hard part was pushing the engine so far over toward the driver's side of the bay. It just looked funny, but then the holes lined up. I used a scizzor jack for excellent control (what can't they do).
I removed the scizzor jack, lowered the floor jack supporting the oil pan and the engine nestled down correctly and level into its new home. Truely one of my easier engine installs, and interesting enough to keep my interested.
I recommend the RB bar. They should have mentioned oh by the way you need to chop a little out of your driver's side motor mount edge. Oh well. Like I said it kept things interesting. I'd totally do another 13B into a 12A chassis. A couple minutes with a hack saw and a grinder (optional) is a small price to pay for the bigger engine.
I went to work with an open mind. Eyeballing where to grind the motormount and then grinding it was not a problem. Actually I used a hack saw and then ground a few mm to smooth it out (could be done with a file). Engine sits level. No need for fender washers and both cups are there.
The only hard part was pushing the engine so far over toward the driver's side of the bay. It just looked funny, but then the holes lined up. I used a scizzor jack for excellent control (what can't they do).
I removed the scizzor jack, lowered the floor jack supporting the oil pan and the engine nestled down correctly and level into its new home. Truely one of my easier engine installs, and interesting enough to keep my interested.
I recommend the RB bar. They should have mentioned oh by the way you need to chop a little out of your driver's side motor mount edge. Oh well. Like I said it kept things interesting. I'd totally do another 13B into a 12A chassis. A couple minutes with a hack saw and a grinder (optional) is a small price to pay for the bigger engine.
#24
Yeah, I used a cutoff wheel, filed the mount down to smooth it out, then repainted that section for a little rust protection. All I'm saying is, if everyone that uses the kit is gonnna need to hack their motor mount, Racing Beat should say that in the catalouge. Just when I thought the engine was in, I had to pull it back up, take out the mount and cut a section off. They sell this piece as a bolt on fix but there is still some modification needed.
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