Broke the Cobra again!!

MalcolmV8 · Post by **MalcolmV8** » Fri Jul 04, 2008 12:27 pm

I thought you guys might find this interesting. Cobra's clutch started chattering like mad when engaging and the throw out bearing (TOB) was making a lot of noise. This all happened within one day. So I pulled the tranny.
The retainer sleeve (much like a pipe over the input shaft) snapped clean off the tranny leaving the lower part still in the tranny which is why the TOB was no longer running straight and making the clutch chatter like crazy when engaging.
But worse yet I see I've actually twisted the splines on the input shaft of the tranny. wow and I'm only around 500rwhp and not even running sticky tires for a while.

Notice the retainer still with the TOB.

Not sure if you can see the spline twist in pics but they are not straight.

and here's a few pics of the T56 if you've never seen one. It's amazingly small and only a little bigger than the T5. A little heavier though

I dropped it without my tranny jack and wow that was a handful. That driveshaft is a beast too. I can't believe how thick it is yet been aluminum it doesn't hardly weight anything.

So up next will be a 26 spline input shaft instead of the stock 10 spline, Spec stage 3+ clutch and supporting hardware. $$ cha ching haha - oh well the price of having fun I guess.

Malcolm

cgrey8 · Post by **cgrey8** » Fri Jul 04, 2008 8:52 pm

I like how you say "...only 500rwhp." That's like saying "I only bench press 400lbs. No clue why my elbow joints grind and creek when I bend them. " 500hp is not a small amount and the T56 is only rated to 450ft-lbs torque. If you are pushing 500hp to the rear wheels, I'm sure you are well above 450ft-lbs at the input shaft of the tranny. However, don't they make stronger 10 spline shafts? Although I guess if you have to replace the shaft, its only a little more to upgrade the shaft to a 26 spline and replace the clutch to match. Otherwise, sorry to hear about your mechanical mishaps. But when you are pushing that kind of power, you can't expect parts to hold up forever even if they were rated for it. But at least you got the Blue truck to fall back on. I'm sure it is no substitute for 500rwhp even with the V8 and AWD setup.

When you get the tranny back up in there, see if you can take some pics around the fork area. I've always been curious how I would fab up a bracket to hold a clutch slave if I ever ran a T56 in a Ranger. For this truck, I just can't justify the cost since I already have a strong aftermarket T5 with nearly identical gear ratios to the T56. But for a future Ranger project, I've often considered running a T56 since they are typically stronger than even the aftermarket T5s.

MalcolmV8 · Post by **MalcolmV8** » Sat Jul 05, 2008 12:42 am

I haven't removed the bell housing but I could for pics. I've found out the 26 spline input shafts are on back order so I may just put another stock 10 spline back in and replace the retainer sleeve and TOB and call it good for now. I mean it lasted 23k miles first time around.

Actually only 500rwhp on these cobras is pretty mild. Consider that when I first bought it the only thing I did was put a cat back and cold air on it the thing dyno'd 411hp to the rear wheels. Since then I've ported the blower and changed the pulley and had a custom chip burnt for those two mods and it dyno'd 486 on a really hot (almost 100F) day and a few months later I went back on a cooler day and it dyno'd 512 to the rear tires. So I just call it 500 which is probably average in the middle. Now the guys that make real mods to these cars or do blower swaps run 650+ hp to all kinds of insane numbers. They are the ones usually breaking things.
Asides from the input shaft on the stock T56 they are not doing any other mods and they are NOT breaking them so I'm curious if they really only have a 450 lbs rating as you stated?

Considering the cheap fix should only run me around $100 ~ $200 I may go that route. If I wait on a 26 spline input and all the other goodies like new clutch etc. it'll run me around ~ $1200. A huge difference. Considering I'm hurting for cash right now I may just put another 10 spline in. Dunno still thinking about it

Oh and BTW I definitely recommend the T56. It's one hell of a nice tranny to drive and the gear ratios are awesome.
And no the blue ranger doesn't even hold a candle to driving the cobra. It's like going to a 3 cylinder pruis with a flat battery after driving the cobra.

cgrey8 · Post by **cgrey8** » Sat Jul 05, 2008 5:03 am

I agree, the T56 is a good, strong, transmission and a lot smoother shifting compared to the 3550/3560/TKO series Tremecs. However I've heard story after story about how the T56s just don't hold up when you put the power to them...and now you are confirming that. Of course, every one of these stories have been from people with big power numbers...and when I say big numbers, I mean anything over 400hp. Maybe I'm out of date with my gauge of what big hp is? Since I'm just not into racing and making the absolute max power possible, I'd be quite content with 300-350hp. I just wonder if that's too much to expect in a daily driven Ranger that I expect 20mpg from.

But yeah, there are quite a few people on the EEC Tuning forum (most are SBF though, not mod) that are forced induction that are making big numbers and actually having to hold back their motors from their total potential in fright of tearing stuff up. One guy I think said his street tune is actually hotter than his track tune because his track tune has to keep him above 11.50s or he gets kicked out of the place due to no roll cage. He made comment the other day he was considering driving to some back water track to test his street tune on knowing he'd only get one pass and they'd likely ban him...just to see where in the 10s he is at.

However for you, I guess a replacement 10 spline is probably the best way to go given that cost differential. But I would look around to see if there are any stronger aftermarket 10 spline replacements.

MalcolmV8 · Post by **MalcolmV8** » Sat Jul 05, 2008 10:36 am

You know the wonderful thing about the cobra is it's 100% streetable. It's not at all a race car or race tune. It starts and drives like a stock car. It idles smooth as silk and is quiet with full exhaust, cats, and all emissions. It drives smooth and comfortable with all the creature comforts and when I cruise around town with a not so heavy foot (I still have fun in it) I get around 19 mph.
Yet stomp on the gas and go into boost and the car is an absolute beast. I love it because it's a perfect daily driver with no quirks. Drives like a dream yet nail the gas and you'll blow away just about anything on the street.

The way that 4.6 runs (and maybe it's just the quad cam blown version, I don't know) it pretty much convinced me that any other project I build whether it a Ranger or Shelby Cobra kit car etc. will be a 4.6 for sure. To me anyhow there's just no comparison with the push rod motors. They pull hard, rev high and are so smooth and nice to drive. Even the 4.6 Explorer I used to have drove so much nicer than the 302 Explorer.

As for that T56 I haven't decided yet. I may pull the clutch and see what it looks like. If it's worn real bad then I guess I'll go all out on the replacement. If it still looks good I may just put another 10 spline back in with an after market retainer and a new TOB.

Hope you all had a good 4th.

Malcolm

cgrey8 · Post by **cgrey8** » Sat Jul 05, 2008 10:57 am

I've never spent any time with a 4.6L so I can't comment on that at all, but it wouldn't surprise me. Pushrod technology is just more clumsy as compared to putting the cam where the valves are. And yes, the DOHC 4.6Ls are considerably better than the SOHC versions. I would imagine the head is completely redesigned with bigger ports and different compression chamber design. But that doesn't mean the SOHC versions don't share a lot of the same benefits of having the cam on the heads.

I just don't think a 4.6L would be even a remote option in a pre95 Ranger due to the tight engine bay. But I'll have to keep that in mind. I do have a 97 Ranger that I NEVER drive anymore. It's probably been 4 months since it was driven at all. I still crank it and let it warm up. But I really need to just drive it to work every now-n-then just to keep the moving parts movable. Point is, it's either going to get sold or turned into a project itself.

Dave · Post by **Dave** » Sat Jul 05, 2008 12:34 pm

Malcolm,
When you said the Cobra was down, I figured it was the rear end again, not the trans. I too have really learned to love the Mod motor. I'm "Old school" so when anyone had a 450+ motor, it sounded lumpy and got maybe 10-12mpg and had to run a 4.10 gear to run the times these new ones do.
I've put over 12K miles on mine in the last year driving to work cause it's so much fun, don't care if I'm ruining the value of it.
Good luck!
Dave

MalcolmV8 · Post by **MalcolmV8** » Sat Jul 05, 2008 1:06 pm

Luckily the rearend is holding together just fine now. I'd still like to install the bushing kit that eliminates the wheel hop but for now I just avoid the big burn outs so I don't get into wheel hop. The girdle thing I installed over the IRS pumpkin has helped a lot and will have to do for now.

You are right when most people think of 400 + hp cars they immediately picture loud barely street drivable cars with lopey idles and horrible gas mileage, no low end power and an insane screamer on top end.
My car is nothing like that. It starts and drives like a dream. You'd never guess it was a monster if I drove it normal. Oh and speaking of low end torque. My dyno chart starts out at 480 ft/lb torque and is almost a straight line across the chart. I think it started around the 2300 rpm mark if I remember right. I forget peak torque but it was just a few digits below peak hp. Talk about a tire roaster, right now with the 315 sumitomo cheapo tires I can nail the gas at 60mph and it'll just instantly light them up and hold it as long as I stay on the gas.
Usually when I race people (like non s/c cobras) they get the jump on me off the line because of my current traction problems and I'll be fish tailing all over the place till around 70+ mph and suddenly I'll hook and sling shot past them like they are not even trying. Fun stuff for sure.
I may switch back to nittos but at only 1000 miles per set they were getting expensive and I've started using the cobra as my daily driver so it makes it tough.

cgrey8 · Post by **cgrey8** » Sat Jul 05, 2008 6:30 pm

The strength of the 4.6L mod block is what's so impressive allowing people to get those HUGE HP numbers off of 4.6L displacement. Although there are still a lot of people stroking and supercharging SBFs to get similar performance as the 4.6Ls and reporting very well mannered behavior from them. There are a few different 500+hp SBFs on the EEC Tuning site. It's pretty much accepted that if you want to get over 400hp in a daily driver quality engine, it has to be supercharged. The supercharger is the key to getting both big torque and driveability. You get the benefit of a fairly mild motor and lower loads so it drives like a stock motor would while cruising. The lopey motors had to make their numbers with the complete combination of displacement, cam, heads, etc etc...and of course high RPMs.

For people interested in making big streetable HP numbers, you just can't beat a supercharger for power production and responsiveness. The turbos can build the same power, but they take a hit with responsiveness due to their inherent lag at low RPMs.

I must have missed something about the rearend, or I just forgot you mentioning it. What happened with it?

MalcolmV8 · Post by **MalcolmV8** » Sat Jul 05, 2008 11:14 pm

Ahh on the rearend well I snapped the driver's side half shaft right as I nailed 2nd gear one time. I think I have pics up on here some where. Those half shafts are insanely thick and it's amazing I snapped it. However after doing some research I found it's the wheel hop that stresses the day lights out of them and causes them to snap. Fix the wheel hop and you fix the half shafts snapping.

Prior to that way back when I was running nittos and hooking up real good I managed to crack the rigid aluminum diff cover. I guess the housing flexed. That also amazes me. That cover got replaced under warranty though

Overall the car has been holding up amazingly well and so far the only things I've broke are caused by mods putting down more than stock power.

Humm well except maybe the brakes. It has Brembo brakes from the factory and they are incredibly powerful. I always get comments from people who go for rides in my car that they can't believe the stopping power. Well for a few nights back to back we were racing up and down doing a lot of 140 to 0 stops and the glowing red rotor and sparks coming out the front wheels was insane. In fact the people in the rear seat of my car could see the red flames/sparks coming out the front wheels. Well after a bunch of back to back runs over and over that night eventually I stopped and let my car sit and I guess the brake fluid boiled because I got in it to leave and my brake pedal went to the floor and I had hardly no brakes. So I drove home real careful and let it sit for a couple hours and it was still hardly anything. I thought wow I broke something but then the next day once it had cooled they were back to normal and every thing's been fine since.
Did I mention my vehicles are not trailer queens

I certainly enjoy them.

MalcolmV8 · Post by **MalcolmV8** » Sun Jul 06, 2008 12:34 am

half shaft post

viewtopic.php?t=1108

cgrey8 · Post by **cgrey8** » Sun Jul 06, 2008 5:19 am

I saw the pics and remembered. Yeah, I can see wheel hop doing that. Shock loads are far worse than any sustained load you could ever put on metal parts since the inertia of heavy moving parts added to the engine's sustained power production can spike the instantaneous stresses sky-high...many multiples higher than the engine could possibly produce on its own. I'd think the best possible investment you could make into the car at this point would be to get rid of the wheel hop which could also have played a part with your input shaft failure.

I guess I'm a little disappointed in the Cobras for having wheel hop at all. I'd have thought they were expensive enough they'd have top-notch suspensions stock. After all, they went to the expense of IRS. Why did they fall short with such an obvious oversight?

MalcolmV8 · Post by **MalcolmV8** » Sun Jul 06, 2008 9:20 am

I have no clue on the IRS. My guess was a comfort issue? To eliminate wheel hop you replace all the rubber in the IRS with really hard replacements. Some joints are urethane and others are solid aluminum bushings. I asked a few members on the forums and they swear it drives just as nice and they only notice a small difference if any but who knows.

dagger · Post by **dagger** » Thu Jul 24, 2008 7:25 pm

I'd love to drive a cobra. I'd really love to put a 6 speed into my ranger, I know that you can mate a T-5 up to the 3.0L with a few things here and there but I just think even a stock engine with a 6 speed would just be fun and original to drive.

MalcolmV8 · Post by **MalcolmV8** » Tue Aug 05, 2008 12:30 pm

Oh yeah chris I did snap two pics or so of the bell housing before putting the t56 back in. Not sure they are the best but it was a rough day to say the least. So much work. I'll see if I can get those up in the next few days for you.
Actually just pulled the tranny out of a buddies 97 Cobra last night and putting in a replacement T45 in there for him tonight.