C-4 vs C-6 Recommendations

I've had a C-4 behind a 514 in my 3200# (including driver) Comet for the last couple of years and make 3 or 4 passes before the tranny gives it up. I'm not qualified to diagnose the problem, so the folks who rebuild it claim to put in "all the right stuff", and I promptly go out and tear it up. I'm thinking of having a C-6 built for the car, but have many people saying go with the 'glide. I'd like to stay with the Ford if possible, but I'm at wits end. The motor makes 620 lbs of torque at 6100 rpm and 751 horsepower at 6800. I have a Munsinger 8" converter that is supposed to stall at 5000, but I'm not sure about that. I've tried using the trans brake (1 pass - Bang!),
leaving off idle - 1 or 2 passes, and foot braking and leaving at 2000 rpm - good for a couple passes. 4 link setup with 4:11 gears and 12" Radial slicks. Very disheartening, aggravating and of course expensive. Recommendations?

Glide would be quicker and one shift and let the Torque work...... no need for a 3 speed unless you just dead set on one.....



Randy

If you want a better C4, there are some out there. Jay at Broader Performance makes a pretty mean unit. But at your HP level and weight, the C4 is never going to be as reliable as a C6.

Lucky for you, Jay also builds some serious bad ass C6's as well. I ran his trannies for several years, and never had a failure.....at 4100+ lbs running low 10's and high 9's.

His service is the bomb, and his prices are reasonable.

http://www.broaderperformance.com

does it lose everything or a certain gear?

C-6!

Alright... I'll jump in on this bandwagon also. What I currently have is a 468 that runs mid 11.30's in an 85 LX also with a C4. Probly in the 450 hp range. I'm in the process of doing an engine upgrade. Quite a bit of an upgrade from what I'm being told. Can't tell you exactly what it'll be when done (cause I honestly don't know) other than sumpthin like a 523,5,7 ??? Hp and torque ??? don't know. I know what I've been told but don't wish to comment on that right yet. I'm just that type of person if you know what I mean.

Now this C4 I have was done prior to me. Meaning it was done by someone before I bought my car. Umm.....and I know this is no doubt a bad ? to ask but.... how much is too much for this tranny to handle? And 514Comet I do not mean to hi-jack this on you! But I do not want to have these type of problems you are faced with and I don't know if I should stick a couple hundred or three in this trans or go for the gusto and have to invest into a glide off the get go since funds will be tight after the engine upgrade. Thanks for letting me jump in

bigblockfox468 wrote:Alright... I'll jump in on this bandwagon also. What I currently have is a 468 that runs mid 11.30's in an 85 LX also with a C4. Probly in the 450 hp range. I'm in the process of doing an engine upgrade. Quite a bit of an upgrade from what I'm being told. Can't tell you exactly what it'll be when done (cause I honestly don't know) other than sumpthin like a 523,5,7 ??? Hp and torque ??? don't know. I know what I've been told but don't wish to comment on that right yet. I'm just that type of person if you know what I mean.

Now this C4 I have was done prior to me. Meaning it was done by someone before I bought my car. Umm.....and I know this is no doubt a bad ? to ask but.... how much is too much for this tranny to handle? And 514Comet I do not mean to hi-jack this on you! But I do not want to have these type of problems you are faced with and I don't know if I should stick a couple hundred or three in this trans or go for the gusto and have to invest into a glide off the get go since funds will be tight after the engine upgrade. Thanks for letting me jump in

rather than invest money in the c4 I'd put it towards the glide IMO.

richter69 wrote:


rather than invest money in the c4 I'd put it towards the glide IMO.

Jon or Randy..... or anyone, any idea what that would cost for the glide $ ?

depends on the hp it needs to take. I put a lot of good parts in mine, other than the stock case its as beefy as you need without going full tilt promod.

I bought a used ultrabell and JW wheel, The tranny turnkey with the good yoke i have about 2500 in it. Converter is one of Lenny's S98 core units which are the cats ass, you'll spend around 1200 for one of those.

I'd say about 1000 worth of the unit was just insurance parts, 1.80 straight cut planet etc, a good 1.76 will take a hell of a beating, thats whats in Blakes currently.

With the C4 i worried about it everytime we went to the track, now I don't even think about it


If your gonna build a stroker deal and keep upping the power build the glide. I spent a lot of money trying to make my c4 live and the car work for it to find its way behind our 306" motor now lol.

a 1.76 stock gear can take one hell of a bunch of power you do not need a 1.8 low gear these are big block they have torque no need to launch it like a small block......


JMHO
Randy

Not to argue but the diff in a 1.76 and a 1.80????????? I doubt you could even feel the diff. From my understanding the 1.80 straight cut is the strongest of the bunch.

And as I said the stock 1.76 will handle more than it should. Over 800hp it aint bad insurance to have a better piece though..

I'm not far from Broader Performance's shop, so think I'll stop in over there and visit. Thanks

Quit pouring your money down a rat hole(C4) and go with the 'glide.

514Comet wrote:I'm not far from Broader Performance's shop, so think I'll stop in over there and visit. Thanks

go ahead waste some more money, or you could just build a glide and be done with it... but it's your money pay now or pay later.......


Randy

the Coug wrote:

514Comet wrote:I'm not far from Broader Performance's shop, so think I'll stop in over there and visit. Thanks

go ahead waste some more money, or you could just build a glide and be done with it


Randy

Meaning...

MEANING that c-4 will break again...... there are so many more good parts for the Glide than the other trans now days and they are about 1/2 or less what it cost to build a c-4 or c-6 and besides you have a bunch of Torque with the BBF why use a 3 speed? so go in Broader performance and see what it will cost you for parts, then go online and see what parts cost for a glide..... I know this is not the answer you wanted to hear but the truth is the truth..


Randy

what about the weight of the car! Is there a limit on the weight? for which a glide will handle!

Honsetly for the original posters combo I feel the 3 speed is a better choice righr now. Later if you build a bigger motor then yes poweeglide. If your close to Broaser performance cart you c4 stuff down there and get him to fix it, right now thtas your best bang for the buck. A c4 should handle what you have no problem.

richter69 wrote:Not to argue but the diff in a 1.76 and a 1.80????????? I doubt you could even feel the diff. From my understanding the 1.80 straight cut is the strongest of the bunch..

Jon I am going to call a B.S here now use your head, the 1.80 planetaries are slightly bigger, and the sun gear is 1.65 in Dia. now the 1.76 sun gear is 1.85 in Dia and Truth is the sun gear is what takes the Major load in the trans, so I the extra .200 in the material makes for a much stronger setup....I have seen 2 of these 1.80 broken both aftermarket and it sun gear is where where it broke, I also have seen 1, 1.90 broken and it broke the same place The Sun gear.....


Just an observance but makes sense to me...

Randy

A built up C6 will take the punishment but is heavier that either the glide or c4 for less of the green stuff. Take your time and find what works for you.

'65 T-BOLT wrote:what about the weight of the car! Is there a limit on the weight? for which a glide will handle!

some guy's say #3200 car but many cars with up in the #3900 are running them and no breakage....I know a guy that had a #4000 chevelle running 9.50's with a glide and hit Nos on top and I can't remember him breaking one...the only ones I have seen broken were in Dragsters....at #1800.

I know Frank Merkle has a c-6 running in the low 7's but I would not guess or venture what he has in it?????????



Randy

[quote="the Coug"]

'65 T-BOLT wrote:what about the weight of the car! Is there a limit on the weight? for which a glide will handle!

some guy's say #3200 car but many cars with up in the #3900 are running them and no breakage....I know a guy that had a #4000 chevelle running 9.50's with a glide and hit Nos on top and I can't remember him breaking one...the only ones I have seen broken were in Dragsters....at #1800.

Randy

I know Frank Merkle has a c-6 running in the low 7's but I would not guess or venture what he has in it?????????

thanks Randy for the input, I broke my Performance Automatic C4, just behind the tail shaft mounting bolts(looks that way) might be at the speedo cable as per Frank Merkle told me when I broke it last year.I've been so pissed at the car its still in the car, now its the first of the year and time to get the stock 460/c4 out and get the 521 back in there!

Jason

jason if you wanta 3 speed I would get with Frank and have him help you thru the build and get one of his brakes, I think he is the formost on the c-6 trans, I see lots of people wanting to run turbo 400's but I have seen problems with them when the let off and shift in neutral it sometimes lays the Sprag over and then it is rebuild time....With Franks buildup and full roller bearings I think the drag is not that much...


Randy

Randy, have you run a Merkl C6?

Greg_P wrote:Randy, have you run a Merkl C6?

no I stopped running c-6 many years ago, but from reading here I think frank is the man on c-6 trans.... somehow he has figured out how to do away with the 2nd to 3rd gear flair, most have...........


Randy