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Pertronix

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60w427

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Pertronix (and 5 or 6 speeds)

I got rid of my points this week and installed a Pertronix unit (the one without the magnets.) I checked the dwell afterwards and it's at 24. With points it's suppose to be 28-32. Does anyone know if this is correct. The reason I'm asking is that I'm running at 200* now at the themostat, up from 190*. This is at 70 on the highway. Timing is the same at 8*. It took a lot of time and work to get it down to 190*. Any thoughts?
 

Rowdy1

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That's It

Timing and 4:11 will do that. You and I need a 5 speed;)
 
6

60w427

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Rowdy - I was told to get rid of the rat and go back to a mouse. I like your answer better.:cool
 

Verle

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Tulsa, Oklahoma
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White 57 FI, 65 Nassau Blue, 94 ZR1 Red/Red
A Doug Nash 5 speed and a 3:08 gear is a very good combination in my 57.

Velre
 

Rowdy1

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Velre or Verle?

Just how much trouble was it getting that five speed in the 57? I'm really wanting to do that to give me a highway gear, but I'm not willing to give up the the 4:11 snap.
 

Verle

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Location
Tulsa, Oklahoma
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White 57 FI, 65 Nassau Blue, 94 ZR1 Red/Red
The 5 speed is a very tight fit, but it does fit. It does not require cutting any fiberglass, the shifter came out in the right place.

I had to fabricate a transmission mount out of 2" X 3/8" steel strap and bolted it to the two front transmission mount holes in the frame. See photo. So, no cutting, no drilling and some fabrication.

I did it without taking the engine out but it would be considerably easier if the engine was out.

The Doug Nash yoke is large so I had to get an asymetric u-joint to adapt it to the stock drive shaft.

With a 3.08, the first 4 gears are actually better (lower) than a 4.11 with a close ratio 4 speed and 5th gear is 75mph at 2800 with tall 235R15.

Verle
 

Tom Bryant

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Nice job on the mount Verle. Do you have a photo of the shifter on the inside?

Tom
 

Rowdy1

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Thanks

Tom, you beat me to it, I was going to ask the same question. I have the means to fabricate a mount, I was under the impression I'd have to change the tunnel hole for the shifter as well, being told the shifter sits back almost two inches from a stock mount. That may be for a Richmond trans, it's been a while since I researched it and have since found other homes for the money I had set aside for the 5 speed. I have the same size tires on the 62 but what I really like is the 2800 @ 75MPH you speak of and being just as quick if not quicker with a 3:08.
 

Verle

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Location
Tulsa, Oklahoma
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White 57 FI, 65 Nassau Blue, 94 ZR1 Red/Red
I'll take a picture of the shifter if you like but it looks just like any other 57 standard shift.

My Doug Nash has a Hurst shifter so I ordered the repro 57 stick that bolts on the Hurst.

One difficulty is the bolts that secure the stick to the shifter eventually rub a hole in the boot. I installed a used boot out of a 65 below the 57 boot to help insulate and take the abuse.

With the 4-speed plate in place everyone assumes it is a 4-speed and I don't tell them any different.

And the shifter really did come out the right hole with no cutting.

I verified that before installation by laying the Doug Nash next to a 4-speed and doing a lot of measuring.

Verle
 

Rowdy1

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That's OK

Thanks for the info. That's something I REALLY want to change in the 62. As I said earlier, I will NOT change the gearing 1st thru 4th, it's just such a rush, but it would be SOOOO nice to have that highway gear. I'm not a top end fanatic or for that matter, I wouldn't run much over 70, but it's the RPM's you turn at that speed. When I get around to it I'll do some serious ratio investigating.
 

Tom Bryant

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This sure looks like the hot setup. What are the gear ratios in the trans?

Tom
 

Verle

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Location
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White 57 FI, 65 Nassau Blue, 94 ZR1 Red/Red
Doug Nash and Richmond Gear come with various ratios.
I have 3.27 2.13, 1.57, 1.24 and 1

3.27 x 3.08 = 10.07

2.20 X 4.56 = 10.03

so the Doug Nash is like a 4.56 with a close ratio 4 speed in first gear.

Doug Nash Close ratio 4 speed with 4.11
1st 10.07 9.04
2nd 6.56 6.90
3rd 4.84 5.38
4th 3.82 4.11
5th 3.08

So the Doug Nash is wider ratios through the gears but it works out well for me on the street and highway. In town I drive in 4th gear a lot.

Verle
 

Tom Bryant

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You get the benefit of an overdrive with the 3.08s but the 1st gear of a 4.56 plus it keeps your pinion speed down. :cool How does the Doug Nash compare pricewise to a Richmond?
 

Rowdy1

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Size Difference

I'm not sure, but I "think" with the Richmond the shifter is back 1 to 2 1/2". Like I said, when I get close, I'll start the research. I've heard good things about all of them, Tremick, Doug Nash, Richmond. Might be next winter's project, this year is the place to do it, FINALLY, the garage!:upthumbs
 

Tom Bryant

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Lou,

Check out this Garage Thread for some discussion of our favorite room in the house. When you get to the end of it tell us what your garage plans are.

Tom
 

Verle

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White 57 FI, 65 Nassau Blue, 94 ZR1 Red/Red
Since Richmond bought Doug Nash I suspect all new transmissions are "Richmond".

I try to watch Doug Nash prices since I would like to get another one. I have seen them from $800 to $2000, depending on condition. Make sure to get a street version and not a drag race version and check what ratios it has.

New Richmond 6-speed with overdrive is well over $3000.
I suspect the shifter position had to move to make room for the other gear in the 6-speed. The pictures I have seen look like the Richmond 5-speed uses the same case as the 6-speed.

Verle
 

Rowdy1

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Lake Hopatcong, NJ
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1962 CORVETTE-SOLD 2004 Z16 Z06 CE
5 Speed

Actually I was thinking I heard that about the 5 speed, being 1 to 2 " back on the shifter. Do you have a source for information on dimensions, ratio's etc.? Where are you looking for these and why do you say the street version not the race one? I'm going to make the change, I need to make sure I have all the bases covered before I plunk down the $$$$$. Anything you have I'd appreciate Verle.
 

Verle

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Messages
103
Location
Tulsa, Oklahoma
Corvette
White 57 FI, 65 Nassau Blue, 94 ZR1 Red/Red
As I have stated before, I have a Doug Nash (not a Richmond Gear) 5-speed in my 57 and the shifter is in the same location as a 4-speed Muncie, both in distance from the centerline and distance from bell housing. A new Richmond 5-speed may be different. I did not have to cut any fiberglass. The shifter came out the hole and does not hit front, back or sids when shifting.


Richmond previously had 6-speed dimensions on a drawing on their web page:

http://www.parts-pro.com/index.html

Since they have redone their web page I don't know if it is still there.

The dimensions on that drawing show the shifter 21.57" from the bellhousing and 2.75" from centerline. I think (not positive) the Muncie is 18.125 from the bellhousing and about 2.75 from centerline.

I am only positive about the Doug Nash 5-speed because I have one in my car.

The drag race version is made for power shifting so the syncronizers (if they have any) will not work well in normal street driving.

Verle
 

Rowdy1

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Joined
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1,180
Location
Lake Hopatcong, NJ
Corvette
1962 CORVETTE-SOLD 2004 Z16 Z06 CE
Thanks

I'm in the process of searching for a Doug Nash for the reasons you stated above, shifter location. I'm not sure, but I think all the Richmond & Tremick 5 speeds are top shifters and even though the measurement from the bellhousing may be close, the center may not be. I "think" the overall size of the Richmond is actually much larger then a T10. Actually, I'm getting VERY confused. I've sent an email to Tracy Performance Corvette whom sells new and rebuilt parts and has been specializing in corvettes since the sixties and does big block conversions on C1's. Unfortunately, they're in Detroit and I don't have any books with pictures and or measurements. Maybe you know, how much difference if any is there with where your shifter hole is compared to my 62? I wish I had the $$$$$ to give it to someone and say "call me when it's done" (wishful thinking):(
 

Rowdy1

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Location
Lake Hopatcong, NJ
Corvette
1962 CORVETTE-SOLD 2004 Z16 Z06 CE
OUCH!!!

Well I found a Doug Nash 5 speed at Tracy Performance in Detroit. Brand new with a Hurst competition plus shifter $2350 + shipping and handling around $100. Should anyone know of a better deal, please don't hesitate to let me know. I'm going to keep looking but I think that's pretty much the going price.
 

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