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Author
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Topic: Close Ratio or Wide Ratio
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69machI
Journeyman Posts: 57
From: nova scotia
Registered: Jul 2001
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posted 08-16-2003 11:06 AM
 
I will someday be converting my 69 Mach 1 from auto to a Toploader. A friend has just received a toploader in a parts deal and offered to sell it to me for a very good price. I looked up the tag info and found that it is a wide ratio. I have always assumed that I wanted a close ratio for brisk driving on back country twisty roads. I have never driven a toploader of any description in the past, so it is difficult to know how much difference this makes. My questions are as follows;
- How much street driving difference between wide ratio and close ratio?
- Will a flywheel from a 289-302 fit my 351 cleveland
- What is the difference between a 157 tooth flywheel and a 164 tooth flywheel?
- Also, the top left bolt ear (flange) where the transmission fits to the bellhousing is broken. Does this automatically make the transmission junk? I know guys who are great at welding special materials.Thanks
Trev ------------------
69 mach I w/351c
91 f150 4x4 swb
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Rory McNeil
Gearhead Posts: 1889
From: Surrey, B.C. Canada
Registered: Nov 2000
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posted 08-16-2003 11:42 AM
For almost any street or strip use, the wide ratio is the way to fly. The wide ratio has a 2.78 low gear, while the close ratio is only 2.32, which would provide considerably less "grunt" off the line. As for the flywheels, I THINK either would work, as long as they are the pre 1980 28oz imbalance units, but the correct bellhousing & block plate will be required, as the starter location is different for each. I would imagine that most 302 flywheels are going to be for a 10 1/2" clutch, however, I used to own a 70 Mustang was a 351C 4v, & it had a 11" clutch from the factory.
As for the mounting ear, no, the trans is not junk, although hopefully the break is not open, ie: gear oil could leak out. If you have the broken piece, have it welded back on,and don`t try to force the trans into the bellhousing like some previous klutz did! Good luck!------------------
78 Fairmont 428 4 speed 10.20@130mph
80 Fairmont 302 5 speed 12.8@105mph
85 Mustang NHRA Stocker 302 5speed. soon to be under the index!
59 Meteor (Canadian Ford) 2 dr sedan 332, auto
74 F350 ramp truck 390 4spd
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n2oMike
Gearhead Posts: 3058
From: Spencer, WV
Registered: Jan 2001
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posted 08-16-2003 11:52 AM
quote:
Originally posted by 69machI:
- How much street driving difference between wide ratio and close ratio?
- Will a flywheel from a 289-302 fit my 351 cleveland
Wide ratio transmissions have more pickup from a standing start since first gear is lower. The wide ratio unit will work on curvy roads just fine. As long as the engine's powerband isn't extremely narrow, the gear spread will be just fine. The wide ratio toploader actually has closer splits than either a T5 or Tremec. The toploader has a 2.78 1st gear, the T5 has either a 3.35 or 2.95, and all Tremecs have a 3.27 first. All have a 1.00 4th ratio. quote:
- What is the difference between a 157 tooth flywheel and a 164 tooth flywheel?
- Also, the top left bolt ear (flange) where the transmission fits to the bellhousing is broken. Does this automatically make the transmission junk? I know guys who are great at welding special materials.
Many (most that I've come across) 164 tooth flywheels are drilled so they can be used with an 11" clutch. They are also slightly larger in diameter. This means they need a matching bellhousing with the starter mounted in the correct place. So... If you use a 164 tooth flywheel, use a matching bellhousing. I don't have measurements for each handy, so maybe someone else can help you with that. I believe the bellhousing thing came up recently, so you may find that information using the 'search' feature. As for the broken ear... I've seen people run transmissions that were held in with only three bolts, but wouldn't recommend it for any hard use. If you know someone who is good at welding cast iron, make sure the ear gets welded back in the correct place by bolting the transmission and the ear to the bellhousing before the first arc is struck. They don't need bolted on too tight, just what's required to hold them in the correct orientation. Have the guy go SLOW. After it's cooled, unbolt the unit and weld the backside. A friend with a 400 small block chevy running alcohol cut a ditch between two cylinders when a head gasket blew. A local weldor used a nickel rod in a stick welder to fill the gap. The block was machined and everything turned out great. It can be done, just make sure it's done right. Good Luck! ------------------
Mike Burch
66 mustang real street
302 4-speed 289 heads
10.63 @ 129.3
http://www.geocities.com/carbedstangs/cmml_mburch.html
http://www.fortunecity.com/silverstone/healey/367
http://www.mustangworks.com/cgi-bin/moi-display.cgi?220 [This message has been edited by n2oMike (edited 08-16-2003).]
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69machI
Journeyman Posts: 57
From: nova scotia
Registered: Jul 2001
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posted 08-16-2003 01:08 PM
Great info, thanks for the help guys. Off the line grunt is good but rowing through the gears as I'm going in and out of corners is what I'm aiming for.Trev
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bifs66
Gearhead Posts: 313
From: Maryland
Registered: Apr 2000
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posted 08-16-2003 04:22 PM
I have always been of the mind set that a close ratio was best for drag racing. At least, that was the case in years past. Didn't Ford typically install close ratios in their performance, production cars, including drag racers? Wasn't the wide ratio used mainly in the average "driver" with rear ratios in the 3.00 range? That's why the 2.78 first gear was used... to give a little grunt off the line with that high rear. As I remember, those who special ordered low rears (4.11 and up) typically opted for close ratio 4 spds. Since both trans are 1.1 in 4th, and you want something around 6000 rpms (~power peak) through the 1/4 mile lights, a rear in the 4:11 range is required. This being the case, the 2.78 1st is not as advantageous to ETs as keeping the engine in its power band for more of the 1/4 as the close ratio would do. There is one new element that may have an effect on things, and that is the improvements in traction. I doubt that that 2.78 1st and a 4.11 rear could have hooked up back in the 60/70s with the old tires. So, maybe advances in traction could now provide some advantage in getting off the line for the wide ratio. It would be interesting to see a direct comparison of the two transmissions in the same car on the same day at the same track. The 66 Fastback has 4.11s and a close ratio; and it's still severly traction limited in 1st gear. ------------------
Bernie Frank
66 Fastback restomod project
85 GT (preserved)
2000 SVT CONTOUR
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