Drive shafts

[magindat]

Originally Posted by takedown

it almost took me an hour to put on the pro Gard.

Originally Posted by takedown

That is why I am NOT a mechanic.

Good thing!

The summary of the JW monologue is: the flex is inherent to the material, not the balance.

Just call Dennis, ask him for the 'right' drive shaft. Tell him your CC number. Be happy and more importantly, safe.

[magindat]

Originally Posted by KillJoy

I do not see ANYONE on this forum driving 128mph for more than a minute or two AT MOST!



KillJoy

Haven't seen me then, have ya?

130+ sustained with 4.10's about 3-4 times a year....

[Stranger in the Black Sedan]

The stock D/s is good to around 130. The MMX shaft HAS to be better than that because it's lighter and stiffer at the same time. Whether the factory "rated" it for higher, I don't know. But the MMX junkyard CVPI shaft is going to afford an improvement over stock. It is, after all, an MMX driveshaft.

[Dennis Reinhart]

Originally Posted by VicsEvilBrother

The stock D/s is good to around 130. The MMX shaft HAS to be better than that because it's lighter and stiffer at the same time. Whether the factory "rated" it for higher, I don't know. But the MMX junkyard CVPI shaft is going to afford an improvement over stock. It is, after all, an MMX driveshaft.

Ok, lets do the math, stock shaft 128 MPH. MMX 130 MPH - 128 MPH = 2 MPH gain. And still will not be safe if you have 410's and exceed 100MPH, but I understand cost is cost, all I am trying to explain is reason behind the Dynotech drive shaft. And I believe I have done that.

[Stranger in the Black Sedan]

I would have to do the math w/ the MMX shaft. I have a driveline critical speed calculator on the PC somewhere. I have a hard time believing MMX only afforded 2 mph over aluminum. Ford would not have made the shaft if that were the case, it just wouldn't be cost effective. You'll get more than 2 mph critical speed variance due to imperfect balancing. I'm not arguing, just trying to acknowledge that the stock MMX shaft on the CV's is probably not as worthelss as people think.

[red]

Originally Posted by VicsEvilBrother

I would have to do the math w/ the MMX shaft. I have a driveline critical speed calculator on the PC somewhere. I have a hard time believing MMX only afforded 2 mph over aluminum. Ford would not have made the shaft if that were the case, it just wouldn't be cost effective. You'll get more than 2 mph critical speed variance due to imperfect balancing. I'm not arguing, just trying to acknowledge that the stock MMX shaft on the CV's is probably not as worthelss as people think.

Talk to Darrin about the construction of the Police MMX driveshaft (he's worked with these).

Personally, I'm not wild about the quality on the Dynotech after seeing several (new and under the car). I'm planning to have a custom 4" 6061 T6 aluminum shaft made by Dennys Driveshafts (they can balance up to 10,000 RPM--my request is 6500). Dennys is extremely well known in the racing community.

If anyone is in the Kenmore, NY area and interested in visiting their shop to get drive shaft measurements taken, let me know. If so, I'll order a drive shaft from them and report back to the site with pictures and such. There's about a three to four week lead time for their products.

Also, concerning cost... $500-$600 is expected for a 4" 6061 drive shaft. I called many places in my search.

[Stranger in the Black Sedan]

Red, a 4" aluminum shaft is going to be heavier than the stock 3.5" shaft, and not have that much higher of a critical speed. I don't think you are going to gain anything at all over stock, other than strength (but you are not going to break the stock shaft anyway)

[red]

Originally Posted by VicsEvilBrother

Red, a 4" aluminum shaft is going to be heavier than the stock 3.5" shaft, and not have that much higher of a critical speed. I don't think you are going to gain anything at all over stock, other than strength (but you are not going to break the stock shaft anyway)

You're right about the weight; a 4" is 1 to 2 pounds heavier than stock (didn't you make a steel--not chromo--shaft?... that's on the order of 5 to 10 pounds heavier). However, this 4" 6061 is not a significant increase in weight, and while the little bit of weight could contribute to the whipping, the diameter and wall construction will increase the critical speed. If you don't believe me, call any reputable drive shaft shop, describe to them the problem we have on our cars, and ask them how to solve it (their answers will be material, decrease weight, and increase diameter). Even Dynotech claims their 4" 6061 to have a higher critical speed than their former 3.5" MMX.

[Stranger in the Black Sedan]

You're right, our stock DS has around a 6000 rpm critical speed, which translates to around 140 mph w/ 3.55 gears. So your 4" 6061 would afford you another 30 mph, assuming 3.55 gears.

Yeah I still have a 3.5" mild custom shaft for this car, sitting in the garage, balanced and w/ new yoke and u joints. That had actually a few hundred rpms higher critical speed than the stock aluminum shaft, because although the steel is a lot heavier, it is also a whole lot stiffer than the aluminum. Higher critical speed was not why I built it though. Why, do you want it? I am not going to ever use it again. I was trying to isolate driveline noise at the time I had that brilliant idea. Surprise, steel transmits noise better than aluminum. So that was the complete opposite of what I wanted to do. But that steel shaft I have is the friekin strongest thing ever, save for moly. 3.5" even in mild steel, is JACKED.

[Dennis Reinhart]

Originally Posted by red

Talk to Darrin about the construction of the Police MMX driveshaft (he's worked with these).

Personally, I'm not wild about the quality on the Dynotech after seeing several (new and under the car). I'm planning to have a custom 4" 6061 T6 aluminum shaft made by Denny's Drive shafts (they can balance up to 10,000 RPM--my request is 6500). Denny's is extremely well known in the racing community.

Denny's is not a vendor here, no vendors here sell Denny's. As fas as I know there is no one that spins a shaft to 10K, but I could be wrong. There are hundreds of happy Dynotech drive shaft owners here, as as far as I know, NO one has had a issue with Dynotech they make drive shafts for the Marauder T bird CV Chevy SSR they sell a Superior drive shaft, Denny's bought one of Dynotech older balancing machines years ago, Ford buys a lot of there drive shafts from Dynotech. They use 6061 T6 aluminum they use superior Dana Spicer U joints they can spin balance them between 6,000/8,000 RPM. Every Florida FHP Marauder has them not one has ever failed, and they run these cars over 150 MPH. Denny's started there shafts after Dynotech, but you can buy from them if you like, but Dynotech is a proven product they are now doing retro kits for the newer Mustangs and Shelby's. If any one wants to get all the facts just call Dynotech ask for Jim Vilapondo 1-248-362-2777

[Stranger in the Black Sedan]

The "better" local shops can spin up to 3k rpms. A lot of local shops only spin to like 1500 rpms. so 6000+ is very good

[red]

Originally Posted by Dennis Reinhart

Denny's is not a vendor here, no vendors here sell Denny's. As fas as I know there is no one that spins a shaft to 10K, but I could be wrong. There are hundreds of happy Dynotech drive shaft owners here, as as far as I know, NO one has had a issue with Dynotech they make drive shafts for the Marauder T bird CV Chevy SSR they sell a Superior drive shaft, Denny's bought one of Dynotech older balancing machines years ago, Ford buys a lot of there drive shafts from Dynotech. They use 6061 T6 aluminum they use superior Dana Spicer U joints they can spin balance them between 6,000/8,000 RPM. Every Florida FHP Marauder has them not one has ever failed, and they run these cars over 150 MPH. Denny's started there shafts after Dynotech, but you can buy from them if you like, but Dynotech is a proven product they are now doing retro kits for the newer Mustangs and Shelby's. If any one wants to get all the facts just call Dynotech ask for Jim Vilapondo 1-248-362-2777

Denny's Driveshaft is not a vendor here, nor is Dynotech. I understand that you carry their product and as a result many people have bought this driveshaft and of course have been quite happy with it (it is a decent product, and I did not imply that it would fail). However, it's not the only driveshaft on the market, and I am personally interested in trying something different. I have looked around and was most impressed by the craftsmanship and quality of Denny's. And, Denny's claim is a balance of up to 10k RPM (see http://www.dennysdriveshaft.com/). Anyway, I am throwing this out there for others to see. If anyone else is interested, there may be potential for a group buy.

[Stranger in the Black Sedan]

No takers on my steel driveshaft-of-doom huh? LOL It was a good idea at the time. If I am ever making over 1000 ft lb I can swap it back on I guess.

[Svashtar]

All I know is I have done several high-speed long distance runs with the car at 125-130, and the car just hums. Sounds like a turbine just cranking away and there's still pedal left, which is scary.

There is no vibration under me at all with the MMX. The only concern I have is that the front end lightens up and feels like it's floating. If we had a real spoiler in back like on many of the mustangs with some slight upward tilt to it that would probably be eliminated as well.

Norm

[Icarus]

I'm running a Denny's 4" shaft on my Linc and love it.
I taked to both Denny's and DynoTech when I was looking and they were both good in giving me the info I wanted. Prices were similar, and Denny's balanced up to a higher speed. I went with Denny's due to the balancing and a lil better info I got from them, and they are closer to me. In the searching around I did, I heard of a few more issues with the DynoTech (but that really doesn't mean alot anyways, as the Linc's are real tight with the 4" shaft from anyone.)
I don't think you can go wrong with either imho