How Much hp can the stock drive train take

[WayneLBurnham]

Re: Re: John - you have a MERLIN 540!!!

Vipers have upper and lower control arms (their sliding-spline half-shafts aren't suspension members), and NHRA won't let them run under 10.0 either

...and they wonder why people shy away from regulated events
to road racing and more dangerous inner city street racing...

...gone so safety freakish two of the best sportscars ever designed aren't allowed to compete all out, no matter how extensive the damned safety mods, when half of what's slapped together to go down those tracks can't pull a 0.5G turn and if you just lose it for a second in them, you probably won't regain control - so you'll need the half-ton 954 point roll cage another safety spec requires...

...but a gutted 2300 pound Nova with 2" wide front tires, no real front suspension, a powerglide with a solid torque converter that pushes a nearly claimer engine to 8500 to just get close to winning is "O.K."

...geeze louise...

JohnZ continues:

; several of my "wild and crazy" Viper customers that run regularly in the 8's and 9's have had to install 9" Ford axles to pass NHRA Tech

So strengthen the rear, not make it safer (worst it will do is BREAK, if you have retention loops and a mechanism to stop the trailing arm from folding up - like the upper control arm) and destroy the handling...handling not being important at all in a car that hits 165 in a quarter mile - and we've never seen them go off course...never....

Those kind of requirements and specs are fine for top fuel levels and wholly synthetic cars, but those "sports" have just gotten away from what they started as.

It's just like the racegunner 1911 .45 freaks with $3000 1500 round raceguns making rules and regulations left, right, and center to keep their personal ideas of what should win IPSC events and hurt it so bad. Like Berettas, HiPowers, Glocks or Witnesses? Like 9mm or .40S&W? Don't worry, we got a regulation to make sure if you are allowed to enter in the event, you'll get so many penalties you won't win...

 

[MaineShark]

Re: Re: Re: John - you have a MERLIN 540!!!

It's just like the racegunner 1911 .45 freaks with $3000 1500 round raceguns making rules and regulations left, right, and center to keep their personal ideas of what should win IPSC events and hurt it so bad. Like Berettas, HiPowers, Glocks or Witnesses? Like 9mm or .40S&W? Don't worry, we got a regulation to make sure if you are allowed to enter in the event, you'll get so many penalties you won't win...

LOL. Try a P7. Most of the 1911 people I've dealt with can't even figure out how to make it work.

Actually, the better analogy would probably be with the Berettas. I mean, the 92G Elite and Elite II were designed for competition shooting, just like the Corvettes were designed to go fast. But people seem to want their thing to be the best, even if it means excluding those who might beat them...

Joe

 

[JohnZ]

Re: Re: Re: John - you have a MERLIN 540!!!

...and they wonder why people shy away from regulated events
to road racing and more dangerous inner city street racing...
...but a gutted 2300 pound Nova with 2" wide front tires, no real front suspension, a powerglide with a solid torque converter that pushes a nearly claimer engine to 8500 to just get close to winning is "O.K."

Actually, they've got pretty good reason for the rule - when half-shafts let go, they flail around and tear out everything in their path, and do a lot of chassis and body damage until the car stops; they can tear out other suspension members, brake lines and hoses, fuel lines, underbody panels, and fuel tanks, all with the car going perfectly straight ahead. With a solid axle and safety loops on the driveshaft (which are impractical on half-shafts), nothing flails around and tears up the car. It only takes one catastrophic accident to either drive the track's insurance rates sky-high (or make it unavailable, and the track closes), or one lost lawsuit to close the doors. Cars that are modified highly enough to be affected by the 10.0 rule aren't street-driven anyway.

 

[Stallion]

:eek Wow! That is some fast car racing! I can't even image that power and speed. It's kinda weird what could happen to a car with enough torque and hp (e.g., the breaking half-shafts). I assume the result could be quite tradgic.

TR

 

[Ken]

... safety loops on the driveshaft (which are impractical on half-shafts)

C'mon John. I was counting on you to help me figure out how to mount a set of half shaft loops for a C4. I don't want to go solid axle (not that I'll get to those times in the too-near future), but I would like to keep the shafts in roughly the area they're supposed to be and not tearing up everything in its way if a u-joint decides to break.

_ken

 

[Stallion]

Attached is what I think is the half-shaft for rear suspension. Am I right?

Thanks!

TR

 

[Ken]

Sir, you are correct!

_ken

 

[Stallion]

Alright! I'm glad I now know. Thanks, everybody!

TR

 

[WayneLBurnham]

Yeah, half-shaft failure is pretty bad....

That's been a constant concern of mine. I thought of armoring the battery box - and even the tunnel for the tranny (I notice there is very little room for a conventional scatter-shield....)

Still, all of these are just engineering problems - what can be solved, should be solved. All of those high strength track events have an element of risk - every system has it's weaknesses. Decent safety regs mandate changes and improvements, they don't prohibit whole classes entirely.

In this case, if nothing else you can increase the size and strength of the half shafts and U-Joints to the point where the differential is the weak point.

One thing, which can be good or bad, with an IRS rear you blow one side you still have power on the other - something a solid axle does not offer. I have first hand experience with that.
If my wheel had broken off (or a C-Clip had failed) on that highway on a conventional solid axle chunk of steel, I'd be dead. (Then again, it probably wouldn't have happened....)

I know one half-shaft retention loop set-up is offered by somebody that attached to the trailing arm somehow, but this is the one from Tom's Differential using their added upper control arm:

Tom's Differentials Upper Control Arm Modification & Half Shaft Safety Loop

This is the 12-bolt I had installed on mine:

Tom's Differentials 12 Bolt C3 Vette IRS Pumpkin

They have some nifty strengthened half-shafts and inner and outer axles too, but that waits for another day and another winning lottery ticket....

 

[sscam69]

Thanks for the heads up Wayne.

Definitely give them a call when I am ready.

I am hoping to shoot for over 500ft-lbs out of a 400sbc running Torque Thrust II's in the back with Nitto 555R's. going to need a strong differenctial to hold all that torque and this is just what I need.

Do they have a core charge. From my understanding of the thread they have you everything and don't have to give them your differential. Correct?

Do you know how much if you gave them your core?

 

[Ken]

... (I notice there is very little room for a conventional scatter-shield....)

On my C4 we'll have to change to a hydraulic release bearing in order to fit the Lakewood bellhousing. Thanks for the info on the loops Wayne.

_ken

 

[WayneLBurnham]

I think the core charge is like a bill-yon dol-lars....

Nah, don't think they charge (or accept) a core...

The thing is an extensively modified Dana 44. Best thing to do is change the thing out when you can afford to use whichever of their's or another's custom axle packages that are not compatible with stock that you choose - it will save money in the long run.

I was out of money and my center center was dying, but I only had enough to do it and a little more (still came to almost $4500 installed, with the other things I had done not related,) but I had my original halfshafts reused for right now, so I can't use their ultimate "1480" package without having the pumpkin cracked open and a part or two changed.

BTW, they also make a custom 10 bolt setup, which is still much stronger than a Dana 44. Since it was only $800 less, I could see no reason for half measures though.

They rate the 10 bolt at 800 ft-lbs and the 12bolt at 1250+.

The thing looked awesome on the inside. Compared to the Dana 44 (like mine was) sitting next to it on the bench, it looked like something for a jet aircraft compared to something for a Mattel toy. (Knowing me, I got the Mattel guts...."what's that noise I hear?"....... :cry )

Ken, bear in mind I do not know if those loops work if you do not use those upper arms - they may, but I don't recall. I'm still undecided on the arms myself, not being a drag racer, or not yet.

After my silent bearing failure, I'm more interested in some sort of remote bearing temperature sensor - but I'm just paranoid, I s'pose....

 

[Ken]

After my silent bearing failure, I'm more interested in some sort of remote bearing temperature sensor - but I'm just paranoid, I s'pose....

Have you checked out Westach's site for a gauge that may suit your needs. Great gauges for the automotive, aircraft and marine industry.

_ken

 

[sscam69]

They rate the 10 bolt at 800 ft-lbs and the 12bolt at 1250+.

Hmmmm I can see how this thread is taking a new direction.

Then I got some questions concerning differentials. I have been looking into buying a 98+ WS6 Trans-Am (T/A) and the stock differential is a "10bolt" but it doesn't seem to hold very long. The popular thing to do is to buy a "Moser 12 bolt" which can hack a lot of power/torque along with really sticky tires. From my understanding you have to swap out the WHOLE rear end. Everything from shafts, carrier etc and bolt in a practically new solid axle setup for the T/A. Comes back to the same question, why bother? From my understanding the gears and carrier are dmensionaly bigger, so I am also assuming that the 12-bolt would not fit in the stock casing. Correct?

If a 10 bolt can hack that much torque why even bother swapping to a 12 bolt, from a general perspective. The cars are putting around 400-600ftlbs and are running Nitto 555R's or BFG DR (pretty much street legal slicks). In general it should be able to hack what these cars are putting out and thens some. This would save ME A LOT of $$$$$ if all I had to do is just swap the carrier and gears that would hack the torque w/o having to swap out the whole rear axle.

In the link they mention they have to cut something (for vette app.), I am guessing its the case? (Have to go back and read it again) I know ones and independent rear and the other is "solid" but the input to the carrier is the same, splined shafts.

Are the "10 bolt" rear ends different designs for both (Vette vs T/A). What I am referring to is carrier and gears setup a different design but both considered "10 bolts"?

For my vette then I would just stick with the 10bolt. I am going to make the car a hot rod with some modern touches to it. Once I get her moving I will be taking it out to the strip to enjoy it. I will be practically be replacing the whole suspension and I would rather just put in stuff that will hack the torque and then some along with the necessary components so that I can run it at the strip. The 10 bolt would be all I need.

 

[Ken]

:confused One reference to gauges can be construed as hijacking a thread? He expressed a concern and I offered a possible remedy for his situation. The rest of the thread has stuck to the original intent, that of how much we can torture the Corvette suspension. :L

_ken

I just realized the creator of this thread hasn't even returned, or at least responded, since the date it was posted. So how can it be hijacked? :L

 

[sscam69]

OH NO NO NO Ken


:L that wasn't directed towards you!! :L, it was towards me:L Don't worry I am an acompliss (sp?), If you don't tell anybody I won't.

 

[sscam69]

Any takers on the questions I had before Kens post?

 

[JHL]

Interesing topic, I have given my Vette some serious abuse at the track and the only thing that gave up on me was a clutch. That being said I don`t have the power some of you guys have but it always on my mind that I am sitting on top of a shaft that could come though the floor. I have seen a couple of Vettes at our track, one ran in supergas with a 9.9 index without any problems in the axle department. Another C4 with CFI was running consistant low 12`s on slicks and nitrous and again he never had any problems.

After I wrecked the clutch and was plagued with inconsistancy at the lights with the 4 speed I had a thought to go with an auto and a solid axle. I called around to see if anyone sold a kit to fit a 9" to the original chassis without cutting and tubbing but no one did, surprising as it is one of the weak points in a C3. There was one place I called that would do the job for me but everything would have had to be custom made - read "expensive"

One other consideration was a Jaguar IRS, they are almost indistructible. I ran with one in a hotrod which had a built 460 Ford and a C6 on slicks. It could pick up the front wheels from the lights and the axle remained intact.

J.

 

[Bullitt]

Frank, I read somewhere that back in the days when it was DIY only, some guys stuffed beefier internals from a 12 bolt into the stock Corvette differential. That some magazines, especially in the '70s, had several articles documenting the modifications necessary. I have yet to locate any detailed information beyond those statements. I'll keep looking, though.

--Bullitt

 

[Ken]

Bullitt, maybe you should have clicked Wayne's link.

Tom's Differentials 12 Bolt C3 Vette IRS Pumpkin

_ken