1975 Plastic fantastic aka Corvette

[SuperBuickGuy]

I had an AirResearch system with basically the same design (just wayyyyyy more ancient computer system - it had dials) and it worked fine.... my only complaint was it didn't use any kind of O2 sensor.

I bought the throttle body system because I don't see how a port system would get me any benefit especially since they started twice the price I paid for this system - yeah, in emissions, or mile-long runners (like the 500 cadillac) port injection might be better - but I care about neither. I also like that I can run a blow through system on it and tailor the intake manifold to the motor.

[SuperBuickGuy]

whew a bit more work






need to get the driveshaft shortened roughly 1".... I may do it myself, we'll see tomorrow

[milner351]

how will you re-balance it yourself?

[Bob Holmes]

You get more done in a day than I get done in a year. Great job.

[SuperBuickGuy]

how will you re-balance it yourself?

you don't. You cut off the end where the weight isn't, if it vibrates, you have to get it balanced.... in 10 or so driveshafts, I've had one need to be balanced.... the reasons I'd consider having someone else do this one is this car is going to be driving with very high driveshaft speeds, and this shaft doesn't move up and down - so it'd vibrate all of the time if it's wrong as opposed to just some of the time in a solid axle car.

[milner351]

Understood, do you have a lathe? I'm trying to figure out how you'd cut the shaft precisely square by any other method.

[STINEY]

Big ole' tubing cutter works great for a nice square cut. You know John, just like the one you borrowed for the 8.8 shortening?

Picture shamelessly stolen from BBR...

[milner351]

I can see that working on an axle Stiney - but there's a step in the driveshaft yoke that centers it in the tube.

I was under the impression you had to remove the yoke (requiring a precise way to cut the weld at the yoke / tube intersection) while preserving the yoke to slide into the newly cut section of tube....

I'm probably over thinking it and SBG will tell us how he's done 12 of them with a cut off wheel and a torch with one hand in a cast after a bike accident.

[SuperBuickGuy]

I do have a lathe that will fit the driveshaft in..... only I won't be using it, I found a brand new one with new u-joints for less than the cost of the U-joints.

[SuperBuickGuy]

I can see that working on an axle Stiney - but there's a step in the driveshaft yoke that centers it in the tube.

I was under the impression you had to remove the yoke (requiring a precise way to cut the weld at the yoke / tube intersection) while preserving the yoke to slide into the newly cut section of tube....

I'm probably over thinking it and SBG will tell us how he's done 12 of them with a cut off wheel and a torch with one hand in a cast after a bike accident.

1 - always grind the yoke off then cut the tube. The cut doesn't have to perfectly square because it slides about 3/8" into the driveshaft tube
2 - always mark a centerline (with indelible markings - like paint)* on the tube and yoke so you get the yoke back in exactly the same spot
3 - you don't need a lathe but it's really nice for doing a continuous weld, you also don't need to cut it on the lathe because it's easy to square the yoke in the tube....


if you run masking tape from yoke to yoke down the driveshaft, then paint with high visibility paint; you'll be pretty close to perfect every time.

if there's any interest, I'll do a how-to with this shaft next monday.

[Bob Holmes]

if there's any interest, I'll do a how-to with this shaft next monday.

Please do.

[Deaf Bob]

I've used a sawzall, portable band and hacksaw...before finding out about the tubing cutters..
The front shaft on the 4X4 viberates at highway speeds if I forget to unlock the hubs..
Derby cars responded sorta well leaving tubes long (like using 2 shafts to make one) .
That is why I love the sliders we use..
Would love to learn different methods...

[SuperBuickGuy]

I've used a sawzall, portable band and hacksaw...before finding out about the tubing cutters..
The front shaft on the 4X4 viberates at highway speeds if I forget to unlock the hubs..
Derby cars responded sorta well leaving tubes long (like using 2 shafts to make one) .
That is why I love the sliders we use..
Would love to learn different methods...

the biggest problem with 4x4 front driveshafts is they have that splined slip yoke; it wears, even when it's not being used and starts vibrating at 30k miles... it's not a huge deal as long as you keep it lubed.... eventually, the splines inside will strip (it'll sound like a ratchet under load and you'll now know what to look for)

[SuperBuickGuy]

I learned something new.... the output shaft on a turbo 400/ST-10 is a Corvette only part.... now no need for a shorter shaft

so I tried out my new seats... I think they will fit, it'll be tight, but it will be awesome to have side bolsters!


and I took the steering column out so I can finish up my tach rebuild what a pain. Normal GM the bottom joint is flexible and you can drop the shaft a bunch.... not so on Corvette, it requires taking the shaft off the steering box

[SuperBuickGuy]

Hood scoops..... suggestions? needs to be 4" - 5" tall. Max length is 55"