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Hey guys it’s my first post on here and I am in a bit of a dilemma. So I have a 302 SBF and a c6 Trans, (don’t want to get a c4 as of now), and so I was looking around to see which crossmember would work but not too sure which to get. I was hoping that someone who has done it before would be able to assist me in finding a crossmember that will fit with little to no modifications, Thanks!
 

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The 302 was out of a 68 mustang and the c6 I’m not sure what vehicle it came out of. It is a SBF c6 and not the BBF c6, but that is all I know about it.
 

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Some or all of the 351C engines came with a C6 with the standard SBF bellhousing pattern.
 

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Unless the 302 is really built, the C6 is a disadvantage simply because it weighs more. Add this to the churn of finding, or building a crossmember and it is even less of an advantage. Just sayin.' Weigh the pros and cons. From personal experience I have gone waaaaaaay out of my way to use something I had only to discover it was just a waste of time and money in the end. YMMV.
 

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You would use a "standard" C6 trans crossmember. After killing a couple of C4's I put a C6 in my '68 289 hardtop.
My trans is out of a truck. I believe my C6 crossmember is out of an even later Mustang, '71 maybe? The yard
indicated the x-members were basically all the same and I don't recall doing any mods to it..... if there were,
it wasn't much.
C6 in a 67/68 is a tight fit. Obviously heavier than a C4. Parasitic horsepower loss is about 50. Flexplate you'd
use is a '69 351 piece. ('69-'80 C6 - 302, 351C, 351W with 164 tooth ring gear, 11-7/16" b.c.)
On the plus side, you will NEVER break it.
 

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I have read about how it’s heavier and takes a good go out of it but I gotta work with what I got, if this thing ever dies the next tranny will be a c4. Anyone know if the FMX crossmember will work? It looks very similar but is only like 50$ compared to the $150 for the c6.

Also, since I believe the c6 is a longer Trans will I need a custom driveshaft?
 

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Unless the 302 is really built, the C6 is a disadvantage simply because it weighs more. Add this to the churn of finding, or building a crossmember and it is even less of an advantage. Just sayin.' Weigh the pros and cons. From personal experience I have gone waaaaaaay out of my way to use something I had only to discover it was just a waste of time and money in the end. YMMV.

Not only heavier, but it steals maybe 25 more horsepower too. They are pretty much nuclear blast-proof, but with the advent of better parts available for the C4, they have been relegated to concourse restorations and big-blocks mostly.
 

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I couldn't turn mine down..... fully built C6, deep pan, wide ratio internal gears and RV/Motorhome servo.
I don't even think it was a grand.
 

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I have read about how it’s heavier and takes a good go out of it but I gotta work with what I got, if this thing ever dies the next tranny will be a c4. Anyone know if the FMX crossmember will work? It looks very similar but is only like 50$ compared to the $150 for the c6.

Also, since I believe the c6 is a longer Trans will I need a custom driveshaft?
Don't know on the FMX crossmember. The C6 one at the boneyard wasn't really pricey. Your experience
today may be different, as this was quite awhile ago.

I believe that the driveshaft is shorter since the C6 tailshaft is longer. Can't measure and give you a quick
response as my '68 has a 9" in it and a Gearvendors hanging off it too. It's a really short DS.....
 

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C-6 is a longer transmission. 67-68 with C-6 is 46 19/32 center to center of the u-joints, but that is for the 390/428 cars with a 9" rear axle. You would need to add 1" to the driveshaft length if you have an 8". As always, get the drivetrain in the car and measure before ordering a driveshaft.

As far as the C-6 / C-4 debate, if that's what you have, then run it.
 

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not sure on an exact trans xmember cause I don't believe that you could get a small block C6 in your mustang from the factory...I may be wrong (sorry Alan) but I believe that you would get an FMX with your cleveland in a mustang. After 71, it may be possible for you to get a C6 with a cleveland, I don't know much about those cars.
Anyway...there are 2 different versions of the C6 xmember. They both have 3 ears to bolt to the tunnel. One is for fmx (small block), one for BB/C6. I had to buy the BB/C6. It was aftermarket from SD. not cheap either. I have several of the 3 eared FMX xmembers. I cannot say if they will work or not. The holes are slotted to give a little wiggle room, so they may be what you need. A 4 ear one will not work as it hits the pan/modulator on a C6.
 
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