New Clutch for the Cobra

[94cobra69ss396]

The clutch and throwout bearing finally gave up in the Cobra a couple weeks or so ago. So I called GTR and they ordered me a McLeod Street Extreme clutch which according to McLeod is good for 700hp/tq. I pulled the trans yesterday and dropped the flywheel off this morning to have it resurfaced.

[Vettezuki]

That's a different level of performance, but I went from a McLeodd Street Performance to a Luk Pro Gold and in addition to being about 1/3 the price is way better for smooth engagement and light feel. It grips at least as well, if not better. It's supposedly the ZO6 OEM clutch, so plenty for me.

[94cobra69ss396]

Did you have an issue with the McLeod Street slipping?

[Shaolin Crane]

My builder always told me Mcleod were the biggest pieces of shit ever. I have never run one though.

[94cobra69ss396]

Well hopefully he's wrong because that's what I'm getting.

[Leedom]

In my research, I have found lots of people recommend the OE/Ford Performance throwout bearing because the ones in most of the kits are not great.

[94cobra69ss396]

I think this one was a Duralast one from Autozone that I bought not that long ago. I will probably be getting one from Ford as you suggested.

[Vettezuki]

Did you have an issue with the McLeod Street slipping?

I burnt it down to nothing in about 12,000 miles. Though to be fair my BHP and its rating were the same 450, so not over spec'd and I had probably 70 passes, and a fair bit of hard driving in those miles. Still, for a street clutch at rating, that's not great, especially for $1k or whatever it was. Definitely prefer my Luk, which is just OE. You may need something well over OE though.

[94cobra69ss396]

My old clutch disc is a McLeod and it probably has 40,000 - 50,000 miles on it. I have a Spec stage 3 pressure plate but the Spec stage 2 disc ( it was a stage 2+ package) broke a while ago and I bought the McLeod disc from GTR. It held up fine behind the 302 but the extra 100 lb/ft of torque from the 347 is just too much for it.

[Shaolin Crane]

In my research, I have found lots of people recommend the OE/Ford Performance throwout bearing because the ones in most of the kits are not great.

Most of the kit ones make noise, I went with an FRPP one and have no noise this time around.

[94cobra69ss396]

I picked up my McLeod clutch from GTR yesterday and will be installing it today.

[94cobra69ss396]

Got the clutch installed and what a difference. The peddle is a lot softer than with the McLeod than it was with the Spec. Also the vibration that I originally had that CHP said was the Spec pressure plate must have been because of the balance of the pressure plate because with the new McLeod pressure plate the engine is still smooth. Gonzalo told me that it might chatter a little but going by the test drive it doesn't. It does grab immidiately though but with the torque of the 347 it's not a big deal.

[Vettezuki]

Got the clutch installed and what a difference. The peddle is a lot softer than with the McLeod than it was with the Spec. Also the vibration that I originally had that CHP said was the Spec pressure plate must have been because of the balance of the pressure plate because with the new McLeod pressure plate the engine is still smooth. Gonzalo told me that it might chatter a little but going by the test drive it doesn't. It does grab immidiately though but with the torque of the 347 it's not a big deal.


Funny, my experiences with the McLeodd -> Luk are similar, especially with pedal feel. The opposite on grab though. The McLeodd was a bit grabby and the Luk smooth, much more street friendly. I have a pretty linear curve with peak torque around 360.

[94cobra69ss396]

I don't know what the Cobra makes down below 2100 but Steve started my pulls at that and it made 330rwtq. I know that if I still had the 302 I might have stalled it a couple times on my test drive but the 347 just lugs down and goes. It reminds me of the way the old Toyota straight 6 was in Phil's FJ40. That thing would lug down to 300-400rpms while rock crawling and then just recover.

[Vettezuki]

You're making 330 from 2,100RPM, wow. Guess it makes sense with a 347 and a blower.

[94cobra69ss396]

I'm not really making much boost at that RPM, only around 2psi. It's mostly the 347.

[94cobra69ss396]

I've put just over 100 miles on the clutch so far and I still love the feel of it. Only 400 more to go before I can give it full throttle. Speaking of not giving it full throttle, Mya and I were on our way to Best Buy to pick up a new radio for it when a kid in a Lexus (I didn't pay attention to the model) decided to tail gate me in an attempt to race while we were on the freeway. He then jumped into the next lane and jumped on it. So I dropped it to 4th (we were doing about 70) and pulled away from him at half throttle.

[Vettezuki]

<< and pulled away from him at half throttle.

That's just mean. :judge:

[94cobra69ss396]

I really want to take the Cobra to Fontana Dragway one day to see what it'll run. I think with a good launch and quick shifting that I might be able to pull a high 10.

[Vettezuki]

It's already impressive. That'd be nuts.

Found my damn dyno sheet finally. I was right around 300 ft. lbs. at 2,000 rpm. That's moderate H&C on a dead stock LS1 bottom end (346) and crappy exhaust. Eventually I'll get new exhaust and a re-tune. Curious what I'd get. Doubt I'd reach 330 though.

[94cobra69ss396]

We have around the same cubic inches. I'm running 9.2:1 compression and probably a smaller cam than you and you have a smaller bore but a longer stroke which should help your torque. Didn't your compression come in around 10.5:1? That helps the torque as well. My advantage is the little bit of boost. I'll have to take the Cobra out for a drive and see how much boost it's making at 2000 but I think it's only 1or2 pounds.

[Vettezuki]

We have around the same cubic inches. I'm running 9.2:1 compression and probably a smaller cam than you and you have a smaller bore but a longer stroke which should help your torque. Didn't your compression come in around 10.5:1? That helps the torque as well. My advantage is the little bit of boost. I'll have to take the Cobra out for a drive and see how much boost it's making at 2000 but I think it's only 1or2 pounds.

My cam is not big. 114 224/224, .550 Static comp should be around 10:5~ Definitely no longer pings on 91, which is nice!

I wouldn't think the tiny amount of boost would net you anything at the low rpms because of the "cost" in turning the blower, but I certainly could be wrong.

[94cobra69ss396]

My cam is only 114 212/218, .545. I don't know how much it takes to turn the blower. I had the blower belt break on me once and I had to order another one so I drove around without it connected for a week. That was with the 302 you could definitely feel the difference when taking off from idle. It was much more responsive without the blower connected.

[94cobra69ss396]

I got the clutch broke in and just in time. While working on the 4 cat X pipe this weekend to make it fit with the torque arm I discovered that one of my tires had a gash down to the cords on the inside wall. The only spare tires I have right now are my M/T ET Streets so I got to test the clutches holding ability. I'm happy to report that it holds great with no sign of slipping.

I also tested to see how much boost it makes at 2000rpms and it makes 1.5psi.

[Shaolin Crane]

Our blowers take around 80hp at redline.

[94cobra69ss396]

At 5800 I'm making 10.37psi and 500rwhp. That 80 is not that bad compared to what the blower adds at that rpm.

On another note I had to get the Cobra smogged and it easily passed this time. It's amazing how much a little intake manifold leak can effect emissions. The also checked every single E.O. number this year and then told me that my blower wasn't legal because it the E.O. came up for 88-93. I had to have them go to Vortechs website and look up the 94-95 kit to show them it had the same E.O. number.

[Shaolin Crane]

I just love to hear about them getting more stringent on smog certs when the car easily passed :rolleyes:

[Vettezuki]

At 5800 I'm making 10.37psi and 500rwhp. That 80 is not that bad compared to what the blower adds at that rpm.

On another note I had to get the Cobra smogged and it easily passed this time. It's amazing how much a little intake manifold leak can effect emissions. The also checked every single E.O. number this year and then told me that my blower wasn't legal because it the E.O. came up for 88-93. I had to have them go to Vortechs website and look up the 94-95 kit to show them it had the same E.O. number.


This is why I like blind refs. :) The EO system is a racket. Regulatory Capture 101.

[Leedom]

:iagree:

I totally think visual should be thrown out short of verifying your motor is what it is supposed to be. If the numbers pass then they pass, regardless of what you have done to the drivetrain.

[94cobra69ss396]

I agree too but at least I don't have to worry about it. I made sure that everything I used had an E.O. Number when I built it so I wouldn't have to worry about it when I came time to smog the car. The only reason I was concerned this time was because of it barely passing two years ago but it looks like that was just because of the intake leak.

[Shaolin Crane]

I agree too but at least I don't have to worry about it. I made sure that everything I used had an E.O. Number when I built it so I wouldn't have to worry about it when I came time to smog the car. The only reason I was concerned this time was because of it barely passing two years ago but it looks like that was just because of the intake leak.

I did the same thing but I think it's bullshit we had to go through that kind of effort.