Who's got the best 60' time with a IRS C4?

[black_89_vette]

Who has the best 60 foot times in a C4 still using the IRS? If you modded the rear end somehow for traction, please let me know how.

[INSANITY]

My best 60' with the IRS was 1.35 but could not make a full pass without breaking something..

[RichS]

My best is 1.48. Like Chris said things start breaking then.

[jpee]

I used to go 1.65 - 1.68 consistently with my C4 when I had the 3500 Vigilante, 3.73 rear (Dana 44) and 26" tires... That held up for awhile..

[PDQUIK95]

1.58-1.61 consistently on a cryoed D44 IRS w/3.73 and Nitto DR's w/2800 stall and beam plates. 50 passes and so far so good.

[hookedup]

1.32, next pass BOOM, clank-clank-clank!

[mackeyred96]

1.61 60'

[REDC4CORVETTE]

1.41 car creations D44 jeb spool 3.90 gears,Dennys nitrous ready shafts,beam plates. 9.37 146 mph.Next run both half shalfs and outer spindel axles,both rear shocks boom and peppered everyone with needle bearings.Crew said car lifted 3 feet in the front as normal and 4 feet in the rear when it blew
It is only money

[BrianCunningham]

Are you guys running the Summer's Brothers 32spline subaxles?

I've got a rear wheel bearing going, and with my engine upgrade, it seems like a good idea and pull the trigger on upgrading my subaxles.

I emailed Summers Brothers about their kit and got the following.

SUMMERS BROTHER RACING

KIT # DESCRIPTION COST

409200 1986 – 1996 C4 CORVETTE HEAVY DUTY AXLE KIT $1,300.00
COMPLETE KIT INCLUDES:
2 OUTTER REAR HUB ASSEMBLY – MODIFIED TO TAKE 30 SPLINES
2 OUTTER AXLES - MODIFIED THE SMALL STOCK STUB SHAFT, BORED OUT AND BROACH TO 31 SPLINES.
2 300M STUB SHAFTS AXLES – MACHINE 30 AND 31 SPLINES, HEAT TREATED FOR STENGTH, AND DURABILITY PRESSED INTO THE YOKE TO CREATE A HEAVY DUTY OUTTER AXLE.

409201 1986 – 1996 C4 CORVETTE HEAVY DUTY AXLE KIT $920.00
COMPLETE KIT INCLUDES:
2 OUTTER REAR HUB ASSEMBLY – MODIFIED TO TAKE 30 SPLINES
2 OUTTER AXLES - MODIFIED THE SMALL STOCK STUB SHAFT, BORED OUT AND BROACH TO 31 SPLINES.
2 300M STUB SHAFTS AXLES – MACHINE 30 AND 31 SPLINES, HEAT TREATED FOR STENGTH, AND DURABILITY PRESSED INTO THE YOKE TO CREATE A HEAVY DUTY OUTTER AXLE.

(Outter rear hub bearings and stock outer axles must be provided by the customer and we will do the modified.)

I'm seeing if they can do it with the new tapered bearings that are out.

[Mr Mojo]

1.67 with 2800 stall and stock Dana 44 with 3.45 gears and drag radials.

[PDQUIK95]

Brian,
I'm currently running stock cryoed stub axles,but have a spare set of used stubs and new wheel bearings ready to send to Jose at Summers if and when I need them.
Rick

[timbradley26]

who did you get the cryoed stub axles from ????? are they they worth going to ????

[0ski_dwn_it]

1.33 with mine, but when I put the gears that should have been in it, both outside spindles broke on the launch.

Went to a solid rear and now the 60' times are a consistent 1.31-1.33 and never breaks.

[Red Rocket]

1.64 60'. 396, ZF6, 4.09, DRM brackets, 15" BFG DR's 17PSI, beam plates, treated ujoints and spindles, 2500 RPM launch. No breakage in ten years of bracket racing.

[qwiketz]

I'd love to get into the 1.40's. Leaving off idle with a stock stall, my car goes high 1.60's on a 17" drag radial.

[hookedup]

Originally Posted by Red Rocket 396

No breakage in ten years of bracket racing.

Ooooooooooooooo, you shoulda' never said that, you've made the Dana gods very angry


But, by that sixty foot time its never dead hooked yet

Dave

[qwiketz]

Originally Posted by REDC4CORVETTE

1.41 car creations D44 jeb spool 3.90 gears,Dennys nitrous ready shafts,beam plates. 9.37 146 mph.Next run both half shalfs and outer spindel axles,both rear shocks boom and peppered everyone with needle bearings.Crew said car lifted 3 feet in the front as normal and 4 feet in the rear when it blew
It is only money

So everything grenaded? Do you leave on the juice or on the motor? What power level is your car launching at roughly. Trans brake?

Man, I thought those parts would last better, but I guess not. Did the case last at least?

[qwiketz]

Originally Posted by INSANITY

My best 60' with the IRS was 1.35 but could not make a full pass without breaking something..

Do you mean breaking something in the rear or in general? How did you get it to hold up to 1.35's?

[ralph]

Some observations from years of experience:

1. If you have a stick and sticky tires and make any kind of power, the Dana is the wrong rear end. It will not make too many passes before it grenades.

2. I've seen several D44s go as quick as 1.30s, but they wont be reliable enough to race on the regular basis. Sort of like playing Russia roulette. Insanity would break the drivers side spindle on almost every pass.

3. 1.8s: D36 hit or miss; D44 will last for many many runs

4. 1.6-1.7s: D44 required to have any reliability. The D44 will become hit or miss, but several have lasted pretty long without problems

5. 1.5s: D44 will generally last about 100-200 passess at best. With cryo'd parts and good spindles and spicer ujoints they will generally last 200-300 passes. Eventually the spider gears will weld themselves to the shaft and break. Of course i've had one with good parts last 2 runs, then the case broke in half.

6. 1.4s: can be done with a spool, but the spindles and ujoints become the weak link. This becomes the point where a solid axle is necessary if you plan to race on a regular basis.

7. Stock half shafts are pretty strong, but i've seen them twist in half coming out of the burnout with a virtually stock car. So they can be hit or miss as well. Carry spares.

Good luck

[Red Rocket]

Originally Posted by hookedup

Ooooooooooooooo, you shoulda' never said that, you've made the Dana gods very angry


But, by that sixty foot time its never dead hooked yet

Dave

LOL,

Only one goal with my 396-- winning trophies in the Pro Class of the Texas Muscle Car Challenge Bracket racing series. Only need to run in the 11's in the 1/4 and 7.63s in the 1/8 to be in this class. Lite spin of the tires and a 1.75-1.8 60' are all I need. Plan to race another 10 years without any breakage.