[corellian corvette]

I recently converted my 72 to a 5-speed but would like to get everything setup to look sort of stock.

Since the 5 speed conversion uses most of the 4-speed attaching points, I'm curious about the clutch fork return spring.

The return spring I purchased is from 73-81. Is a long spring, nearly a foot.

However , I purchased the repro return spring bracket which mounts to the frame, and when I look at the assembly manual it looks like the bracket mounts near the Z bar, which is really close.

So was there a different spring used in 70-72 cars? Is that spring available?

Alternatively, how was the 73+ car hooked up? Is there a correct way to mount the spring?

Any pictures or advice appreciated!

[Held for Ransom]

The 1967-72 Firebird V-8 vehicles used the GM 3899021 spring. OER makes a replacement using thinner gauge wire.
http://www.summitracing.com/parts/OER-3899021/

[Dens71TA]

'72-down had the spring hook into the end of the fork next to the push rod pivot cup. '73-up had it on the other side between the push rod pivot cup and the bellhousing.

[Formula8]

I ended up going to the hardware store, buying 3 univeral springs and using the one that fit best with my headers. I simply went from the return spring in the fork to an available frame hole.

[68bird400HO]

All of the vendors have the spring but the list it as '67-'69. I had a go 'round with PY on this last year as I ordered one for my 71 and they sent me the long one. I did call them on it and I believe they were going to update their catalogs.

[corellian corvette]

Thank you! The installer did a good job making up a bracket to support the longer cable, but Im sorta anal about making it look stock-ish

[John V.]

I realize this is a very old thread but came up in a search and related to my question.

I find Pontiac issued p/n 490622 as the Service Replacement Clutch Fork Return Spring for my '73 (SR for '73 & '74 per the MPC). I am assuming it was the OE spring for '73.

'67-'72 list the Chevy issued p/n 3899021 as the Service Replacement Clutch Fork Return Spring.

Dens71TA in post 3 says the '73 spring was longer due to the location where it hooked to the new for '73 Clutch Fork.

His answer makes sense to me but I wondered if anybody has pix of both springs or good dimensions to compare them.

I want to confirm that I am getting the correct spring.

[Formulabruce]

The repro spring brace that bolts to the frame is made wrong, and heads in the wrong direction. I will get pics tomorrow of both, just went through this with a 5 speed set up from Silversport.

[John V.]

The factory installed Spring Bracket is still bolted to the sub-frame, one of the few remaining vestiges of the original 4 spd that the TA was built with.

The '73 Return Spring dimensions and/or pix would be helpful.

Thanks.

[johnta1]

Try this from the Assembly Manual

73 Bird Clutch

[Held for Ransom]

http://www.forums.maxperformanceinc....d.php?t=651116

[starlightblack]

These are my NOS

[Formulabruce]

I did a VERY VERY short Video on the Clutch Return spring Bracket.. Original, Vs Repop. Its on RUMBLE
This may effect the spring some as the repop would add maybe 2 inches more of spring stretch.
https://rumble.com/vbxidr-manual-shi...speed-m13.html

[John V.]

Fb, that is almost funny if it wasn't sad! Such a simple part but somehow they reproduced it wrong. Trying to visualize it in my head. Seems if you bent the thing the opposite direction you could have it point the right way but the locating tab would still be on the wrong edge and pointing up instead of down. So no way to remake it correctly without a redesign.

Lucky for me, I have the original (well, at least 99% certain it's not a repro). One of these days I'll check it to confirm.

Meanwhile, starlightblack, are yours NOS p/n 490622?

Any chance you can give me a couple dimensions for reference?

OER makes one they claim is correct for '73-'81 Firebirds, looks similar to yours but looks unpainted. But they say the OE p/n is 332521.

That looks like an Olds p/n to me. And I find a supposed new in the GM package 332521 on ebay that shows a LOT more coils on the spring than yours.

So I'm doubting that 332521 is identical to 490622 even if it might be functionally correct.

Dimensions of a known '73 OE 490622 would really help.

Thanks.

[Held for Ransom]

If you look at the assembly manual sheet, you will see PN 332521 is for the Chevrolet 6 cyl. engine combo. Probably different spring tension/length.

[John V.]

Mike, thanks, great catch. I would never have thought to check the 6 cyl application.

According to the MPC, the forward Spring connection Bracket 478471 was ONLY used for the V8,

Tough to tell by looking at the Assembly Manual drawing, but looks like the 6 cyl Return Spring hooks into a hole in the sub-frame without the use of the separate bracket shown for the V8 application.

Guessing the hole is in all sub-frames so if the clutch fork is the same for the V8 and the 6 cyl, I suppose you could use the 332521.

Without knowing where that hole is, hard to know for sure but the way it is drawn, it seems to me the 332521 Spring is longer and probably wouldn't work with the original 478471 Bracket.

So I'm back to seeking an original V8 490622 Spring.

The repro 332521 of course doesn't differentiate between the 6 cyl and V8 application in the advertised description. Yet another example of an incorrect reproduction part?

I'm wondering if that explains why the reproduction 478741 Bracket is made incorrectly. Perhaps it is designed to pick up the "slack" when using the longer 6 cyl 332521 Spring? A case of two wrongs making a right??!!

Hoping starlightblack will be able to provide dimensions assuming his NOS springs are the 490622.

[Held for Ransom]

First I'll list the different spring PN used from '67-'81...
'67-9, all engines, 3899021
'70-2, 8 cyl. 3899021, 6 cyl. 3973088
'73-4, 8 cyl. 490622, 6 cyl. 332521
'75-81, 8 cyl. 498493, 6 cyl. 332521 but books are really confused on it, listing both in both sections.

As I posted in the other thread, my '74 spring was broken. One end was approx. 1-1/5" long and body was over 3.00" long (maybe 40 or more coils). 0.763" body and 0.076 wire. Looked to be painted black.
I got a '75-6 used spring and it was 1-1/2" long, 3.00" long and 7/8" long. Body was approx 38 coils, 0.771" wide and wire was 0.074". Evidence of blue paint on spring.

Spring bracket PN was 478741 for '73-6 and 500920 for '77-81. Which may explain why it looks different.