Engine: R2 supercharger

[jedmu0940]

QUESTION, WHAT IS THE REASON FOR THE SPRING ON MY R2'S
SUPERCHARGER?
JACK

1955 SPEEDSTER LEMON/LIME
1955 SPEEDSTER RED & WHITE
1964 R2 GT HAWK

[41 Frank]

You are probably referring to the spring on the idler pulley that acts as a belt tensioner.

Frank van Doorn
1962 GT Hawk 4 speed
1963 Daytona Conv
1941 Champion R-2 Rod

[sals54]

Yeah, you don't want that belt getting too loose when the torque of the supercharger is kickin in. It'll throw a belt in the best of circumstances as it is.

sals54

[jedmu0940]

Most belt driven components are adjusted by an adjustable(slotted) arm,I have only seen a spring
loaded part as a tensioner for serpintine belts, I suspect there is else something going on here,
but I don't know waht it is.
Jack

1955 SPEEDSTER LEMON/LIME
1955 SPEEDSTER RED & WHITE
1964 R2 GT HAWK

[Alan]

Pictures, we want pics. Keeps us from running around guessing like fools.

[JDP]

The spring is needed for the early blowers because the pulley splits. On later cars, it allows for belt stretch, but can be replaced with a turnbuckle.

JDP/Maryland
Please vote for Sid (64GT)in the NYT contest.

http://collectiblecars.nytimes.com/Contest/

[jedmu0940]

John, I was just now looking thru Ed Reynolds book STUDEBAKER HAWK 56-64 ARCHIVES,and
on page 44, if you have this book, is a picture of the blower with a variable rate pulley
shown. This seems to explain the spring tensioner as you need to keep the belt tight as
the diameter (ratio) changes. Does the 64 R2 still use this type of pulley?
Jack


1955 SPEEDSTER LEMON/LIME
1955 SPEEDSTER RED & WHITE
1964 R2 GT HAWK

[Warren Webb]

That was the supercharger used in 57 & 58. The supercharger used in 63 & 64 wasn't a variable rate, just a single pulley vs. the split pulley used in the 50's. The spring loaded tensioner was still used. The 63/64 version was more simple in that there was no switch on the carburator linkage to control the variable pulley. In that illistration, you'll notice the Mc Cullock cast emblem that covered the solinoid that was part of the variable system whereas the later Paxton unit just had a simple label in that area. See page 107 for a picture of the later unit with label.

60 Lark convertible
61 Champ
62 Daytona convertible
63 G.T. R-2,4 speed
63 Avanti (2)
66 Daytona Sport Sedan

[jedmu0940]

Very interesting, Thanks Warren.
Jack

1955 SPEEDSTER LEMON/LIME
1955 SPEEDSTER RED & WHITE
1964 R2 GT HAWK

[Matthew Wendt]

Yeah, you don't want that belt getting too loose when the torque of the supercharger is kickin in. It'll throw a belt in the best of circumstances as it is.

sals54

Old thread, but I just spent 5 hours re-detailing my 64 R2 due to the supercharger belt throwing off taking the ps and fan belt with it. I have a NOS tensioner, ruined a like new original sc belt, and triple checked all the alignments and that everything else was correct. The belt length was correct as it is super hard to get on, so it can't be smaller. I need to get new belts tomorrow.

I was pushing the car very hard, I drive it rarely, so when I do I like to have fun. I was getting it ready to take to the AACA in Harisburg this weekend to try to get a Grand National first.

Have others had this problem, is the red spring tension that is available the solution or just use a turn bukkle?

Also I bought the 7 3/4 aluminum larger crank pulley (stock for 64 is 7") from Ted Harbit and want to put that on next. Anyone know the belt size needed or have feedback on this modification? The driven pulls is stock.

Thanks,
Matt

[sals54]

A turnbuckle would be a better choice, but still is not fool proof due to the belts being on the outside of the pulleys. Without a tensioner, instead of a "stretcher" on the belts, throwing them will always be a threat. Look on youtube to see some super slow motion video of dragsters. I realize we don't have the same horsepower issues, but you get an idea of what the engine torque is doing to those belts when under severe load. Good luck, though. I do believe a turnbuckle will solve most of your issues, though.

[karterfred88]

There really is no "solution". Belts undergo a stretching and retraction each time torque is applied, the spring "tries" to keep the idler pulley in contact in the stretched condition, but can't always "keep up". If there is a sudden change in torque the belt may find itself off the pulleys-thus flying off. A turnbuckle will tighten the belt tighter, put more side force on the water pump causing early failure. The belt will also "stretch" faster and the cords inside it will break faster, and will then fall off or fail. The design of the belt pathway is a compromise at best. Normal driving, it will work quite well for a reasonable time before belt stretch forces replacement. Note, newer "supercharged" engines use different superchargers, belt types and strategies to slow down their failure-but they fail too. Going fast costs money-how fast do you want to go-for how long? Good luck!!

[Alan]

Alternator/Fan HO 45 1/2" X 13/32" X 38 degrees. Atlas 743. Dayco V268M / V301M / V704. Gates 8463 / 8253HD. Napa 485.
Supercharger HO. 56" X 7/16" X 38 degrees. Atlas 729. Dayco V183M / V612. Gates 8269. Napa 2598.
If you need another brand just ask.

[SScopelli]

As noted the turnbuckle style..

DSC01731 by s blazel, on Flickr

As noted by karterfred88, there are dynamics of the engine being revved and relaxed during a manual shift. I dare say put a GoPro in the engine and see how much that arm moves during a race.. My bet is, you will be keeping the spring..

Funny how we always assume that this was designed was by a "Chimp with a machinegun" and not an edgeecated person..

I'm leaving the spring for the tension arm..