Rear end ratio to high and/or 1st gear ratio to high

[qmdv]

I have a 32 hi boy roadster that I just got running. 281 cu inch flathead. It has a 39 trans with Lincoln Z gears and a rear end with 3.27 gears. I do not like that high of ratio in 1st gear.

Long ago I had a 29 roadster pickup with a 39 trans with stock gears and rear end with 3.27's It had a B engine with an overhead valve conversion. That is why I though my gearing would be OK.

Question is do I change the trans gears or the rear end gears to 3.54. The trans would be the easiest cus the engine has to come out due to an oil leak I cannot live with. Also I have most of the stuff for the trans

[deuce_roadster]

I have LZ sets in both 32 cars, avatar and 5w with 3.54s. Both cars similar engines and both cars are very drivable. I believe no matter what you do with the trans, high gear will still have to go through those 3.27s and seem too high. My 2cents.

[Tinker]

What do you want? Burn outs or high speed? or both. Rearend will be bit better with a lower gear.


Lot of people change out to 3.54 gears to get a bit out of a stock trans, top speed wise. You have a better trans setup. so.... gear the rear. 3:27 means you into at least a 8/9" ford or other. Natural progression is a sbc 350 and a turbo 400.


It's not a 1500hp car. Never will be.

[V8COOPMAN]

Hah.....and now returning to Earth, and quite probably a little more reasonable and useful answer. In the first place, either of the two Lincoln Zep gear sets, 25-tooth or the 26-tooth is gonna kill ya with that 3.27 rear. The most-forgiving of the two (26-tooth) has a 2.33 1st gear and yields an overall 1st gear ratio of 7.62 with that 3.27 rear. Not only does that ratio absolutely suck for initial start from a stop, but overall acceleration ALSO sucks, as you well know! You should remember that those Zep gears were designed to work with a 4.11 rear gear ratio, and then an eventual shift into OD to get on down the road. The 26-tooth with 2.33 1st gear and a 4.11 rear yields a 9.58 overall 1st gear ratio. That is absolutely in the ballpark for easily leaving a stop sign, yet going on down the road briskly at a reasonably low RPM in 3rd gear.


But you have that 3.27 in the back. Since it's quite a bit more trouble to change the rear gear, plus the fact that that low NUMERICAL ratio is wonderful on a level, open road in 3rd gear, I'd leave the rear alone! What I would do is find a complete 28-tooth Ford gear set (the MOST-common, and used thru 1948) with the 2.82 1st gear ratio, yielding an overall 1st gear ratio of 2.82 X 3.27 = 9.22, right in the neighborhood with that really nice 9.58 we talked about in the paragraph above. And being a highboy roadster, you MAY have some really large-diameter rear tires. If so, you MIGHT even consider keeping your 3.27 rear and going with the available Ford gear set that has a 29-tooth cluster and a 3.114 1st gear, times 3.27 rear equals a 10.27 overall 1st gear ratio for getting off the line. Just try to remember that in most any street-driven situation, an overall 1st gear ratio somewhere between 8.25-ish and 10.5-ish is not going to have any trouble leaving a light. The lighter the car is (like a fenderless '32 roadster), the lower the NUMERICAL overall 1st gear ratio that is tolerable. Personally, I'd go with the 2.82 1st, 28-tooth cluster gear set and keep your 3.27 rear, yielding that 9.22 overall. If any of this is confusing, please holler back and we'll try to clear things up. Happy motoring! DD

[V8COOPMAN]

Originally Posted by deuce_roadster

I have LZ sets in both 32 cars, avatar and 5w with 3.54s. Both cars similar engines and both cars are very drivable. I believe no matter what you do with the trans, high gear will still have to go through those 3.27s and seem too high. My 2cents.

Mike...If your Lincoln Zep cluster is of the 26-tooth variety, it'll have a 2.33 1st gear, combined with your 3.54 rear yields an 8.25 overall 1st gear ratio (2.33 X 3.54 = 8.25) which is right close in there with that comfortable numerical window I suggested for the OP in post #4. That's a nice combination with a healthy engine in a relatively light roadster. Dick D

[Mart]

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I have 3.54s and 6.50 tyres on my 41 pickup with a stock motor. I rebuilt the trans with a 15/29 gearset to give me a good pullaway gear.

You can't have it at both ends.

The 3.27 gears will make for good highway driving if that is what you want. If that is what you want, then use a wider spaced trans to compensate.

Basically by choosing such a high rear end ratio you have prioritised relaxed cruising over out and out performance.

If the parts are available I would try a 16/28 gearset.

My roadster has that with 3.54 gears and performs very well with a good balance between performance and cruising. This is with 7.50 tyres.

You have a bigger motor so my gut instinct tells me it would probably be ok.

The 15/29 gearset would give a lower first. But you have a wide ratio drop between each gear. If the 16.28 were not low enough you could go this way.

On the other hand a set of 3.78s would probably give the bang for the buck you desire without compromising cruising too much.

Something needs changing, it's up to you to decide which is easier/cheaper/more advantage for you.

Mart.

[JWL]

Change the trans gears. The LZ gears are problematic for most drivers. The exceptions are stock camshaft, light weight builds.


Some of this drivability problem is affected by(in my case) age. When I was young I had a HEAVY 40 Sedan with LZ gears and a Isky 431 Acel. camshaft. Probably the most useless cam for ANY application. But it was fun and easy to drive. Today, I say it was a stupid converge of parts.

[john in illinois]

I have 3.25 gears and a wide ratio transmission in my roadster. My engine is a 276. I find it very drivable.
I live in the country with a lot of 90 degree corners and I can downshift to second
and not bog down turning. It is also great on the highway.

John

[Automotive Stud]

I think the 3.25 rear and close ratio transmission is a bad combination. If you are set on the 3.25 rear for the highway you could probably swap a 29 tooth cluster gear in the trans and sell your zephyr gears and come out way ahead. If you are set on the zephyrs you should probably go to a 3.78 or lower rear to really take advantage of them.

[qmdv]

Originally Posted by Tinker

What do you want? Burn outs or high speed? or both. Rearend will be bit better with a lower gear.


Lot of people change out to 3.54 gears to get a bit out of a stock trans, top speed wise. You have a better trans setup. so.... gear the rear. 3:27 means you into at least a 8/9" ford or other. Natural progression is a sbc 350 and a turbo 400.
.

Acually it is a 36 ford rear end

[deuce_roadster]

I forgot to mention that there are a lot of hills around my neck of the woods. Gear ratio and tire size decisions make a difference in WHERE you live and drive. I might be able to get away with 3.25s if I lived in Omaha Nebraska. My avatar picture is at 6600' up Mt. Rainier and there are many mountain passes between W. Washington and E. Washington across the Cascade range. Something else to keep in mind.

[V8COOPMAN]

Originally Posted by qmdv

Acually it is a 36 ford rear end

I wouldn't take anything in that "outer space" junk that you quoted in your post very seriously. Also, the YEAR of your rear end is not what's important here. Your ring and pinion ratio is what matters.


Note what John says in post #8 above. I still suggest the gear set with a 28-tooth cluster gear which means a 2.82 1st gear ratio for your light roadster. That is the most-common old Ford gear set out there. The complete gear set out of many '39 thru '48 transmissions is where you'll find that set. That Zep gear set you currently have is an easy sale to someone that doesn't know any better......for substantial bucks! The Zephyr gears are only GOOD for ridiculously-light cars....or for bragging rights. DD

[qmdv]

So now that I will be changing my gears to Ford, what are a set of LZ's worth. It is a 26 tooth setup

[32phil]

I have a set of L/Z gears in a Brookville bodied hi boy roadster, it's very light.
Warmed up 8BA with 3:78 rear gears.
I put the L/Z gears in when I rebuilt the trans a few years ago.
The first thing I noticed was that the car is sluggish taking off from a dead stop.
You have to slip the clutch to get it going. Not much but a little more.
1st and 2nd wind out way longer than the 16/28 gear set in it previously did.
If I had to do it over I would not bother to put the L/Z gears in.
I don't race it, only baby it when it's street driven.
I consider the change to the L/Z gears a step backwards.

[deuce_roadster]

32phil, sounds to me like you have too much cam or too tall rear tires if you are getting that kind of performance with 3.78s. I have a full fender Henry 32 roadster (my avatar) with a 59 series engine, (4" crank, 3 5/16 Ross pistons, metric rings) 2 97s on an Edelbrock super, crab distrib, very mild cam (but have 114 degrees between lobes) 3.54 rear end and LZ gears in a 39 trans. I recently took a friend for a ride who was told there was no way he should use LZ gears in a 32 roadster for the street as it would be bogged down. Well, after pushing him back in the seat from a stop in 1st and taking it out on the freeway (yes I took it to 5500 in 2nd gear pulling onto the freeway) and on the way back I slowed down to 15 mph at the bottom of a hill and then accelerated in 3rd gear going up the hill without it bucking or complaining. Every build is different and tuned differently, depends on a lot of things. My 2 32 cars (roadster and fenderless 5w) with the LZ gears are very easy to drive without any drama. I have over 6000 miles on the roadster.