Changing gear ratios: opinions/suggestions wanted!!

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Wademo

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Has anyone considered a Gear Vendors Overdrive?
 

BigT

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Has anyone considered a Gear Vendors Overdrive?
I just looked those up - very cool! Just very pricy, too. Anyone have any experience with them?
 

mcarlo86

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I had a '78 Winnebago motorhome with a 440 and 727 auto that had a Gear Vendors in it. Was really cool. You could use it to "split shift" so it made it like having a 6 speed instead of a 3 speed. 1st, 1st over, 2nd, 2nd over, 3rd, and 3rd over. Was nice when driving in the hills and having the overdrive really cut the RPM's down so a guy could cruise comfortably at modern speed limits.
 

Sgt Gus

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I don't understand why everyone says they can't keep up with modern traffic. Why the heck not? Just get on the skinny pedal and let it eat. If it's keeping temp and not floating valves, don't worry about it and just drive it.
And run straight pipe, drop the mufflers! Put one of these in the window :flipthebird::)
 

Ricko1966

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And run straight pipe, drop the mufflers! Put one of these in the window :flipthebird::)
What does this even mean? I've dailyed plenty of street cars with steep gears and no overdrive. They all had exhaust,I didn't flip people off. My gears weren't rude or obnoxious to anyone. My gears affected no one but me and my car.
 

Sgt Gus

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What does this even mean? I've dailyed plenty of street cars with steep gears and no overdrive. They all had exhaust,I didn't flip people off. My gears weren't rude or obnoxious to anyone. My gears affected no one but me and my car.
You are being too serious, I'm only making a joke. I would NOT actually flip someone off or try to be obnoxious.
Nor am I criticizing you, I am WITH you.
Problem with texting and my sense of humor is it can be misconstrued.
Not the 1st time I've stepped on toes here.
Seriously, apologies for affending.
Gus
 

Ricko1966

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Sorry,I misunderstood. Have a great day.
 

bucket

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You are being too serious, I'm only making a joke. I would NOT actually flip someone off or try to be obnoxious.
Nor am I criticizing you, I am WITH you.
Problem with texting and my sense of humor is it can be misconstrued.
Not the 1st time I've stepped on toes here.
Seriously, apologies for affending.
Gus

@Ricko1966 is a very serious person. He only jokes about buttered toast, knitting and cat's asses :rofl:
 

Sgt Gus

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@Ricko1966 is a very serious person. He only jokes about buttered toast, knitting and cat's asses :rofl:
I remember seeing that thread. I don't remember what the OP was or if their was a like or dislike of Cats. ;)
 

Ricko1966

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I remember seeing that thread. I don't remember what the OP was or if their was a like or dislike of Cats. ;)
It was one of those threads that just went back and forth,nobody agreeing. So I suggested that next we should argue about if you tie buttered toast to a cats back and drop it which side lands first.
 
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chris3353

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You have a roller cam or flat tappet? Use a gear ratio calculator,use some common sense,like are you at 70 plus most of the time,or just occasionally,etc. I fully believe part of the flat cam problem is too low of rpm on flat tappet cams,they are splash lubricated. Too low rpm I don't think the cams get enough oil.

Sorry for the delay in responding,, did not get a notification..

I run a flat tappet Voodoo lunati 10120700
.437"/.454" 207/213

the motor has been great,, I get ~12 mpg running around town and ~15+ on the highway. The flat tappet cam failure is a myth.. If someone is wiping a cam they need to looks at lifter bores, spring pressure, or bind.

I run solid flats in all my performance motors = zero problems. My CJ7s have hyd flat and for ~20 years no problem,,,, No special oils.

Anywhoo,, At my RPM Under 3000, the benefit of a roller is not there. I spoke to a couple of grinders and the few hp i might gain was not worth the $$$.


Here is my motor build if anyone is in the TBI boat.
 

BigT

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I've settled on going with 3:73 gears and I am keeping my original TH400. Whether I swap in gears and carriers or just swap complete differentials remains to be seen based on what I can find. It might not be what all of you would do, but it fits me, so thanks all for the input and ideas!!
 

Ricko1966

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Sorry for the delay in responding,, did not get a notification..

I run a flat tappet Voodoo lunati 10120700
.437"/.454" 207/213

the motor has been great,, I get ~12 mpg running around town and ~15+ on the highway. The flat tappet cam failure is a myth.. If someone is wiping a cam they need to looks at lifter bores, spring pressure, or bind.

I run solid flats in all my performance motors = zero problems. My CJ7s have hyd flat and for ~20 years no problem,,,, No special oils.

Anywhoo,, At my RPM Under 3000, the benefit of a roller is not there. I spoke to a couple of grinders and the few hp i might gain was not worth the $$$.


Here is my motor build if anyone is in the TBI boat.
The flat tappet flat cam is not a myth,just not near as common as everyone believes. I worked at the same shop 1985-2001 we did rebuilds,full service or carryout,stock or as wikd as you wanted it,we did at least 3 a week I'd say that's a big under estimate, but I've seen flat cams,some worn out in engines that had never been apart, and we had a run for a few weeks where we were getting come backs with flat cams.Never had the problem before,and we didn't suddenly forget how to do machine work or build engines,or break in cams. We changed supplier for cams and lifters and the problem mysteriously went away. It seems we had a run of 1980 ish 305s with 700r4s that had factory cams that went flat,and it's just always been a hypothesis of mine that if they hadn't had O.D. transmissions they wouldn't have gone flat.
 
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