Gears 3:55 vs. 3:73

[Kern Dog]

Thanks Gregory,

I'm a 4spd so the GV isn't really an option for me.

It could be...They offer a GV for 4 speed manual transmissions too.

- - - Updated - - -

Thanks for pointing me in the direction... might be very useful in the future. They have a 5 speed that's a direct swap in available soon

https://www.passonperformance.com/i...documents/Passon_5-Speed_Flyer_2010-11-18.pdf

Available soon.....HA !!!
That transmission has been in devolpment for over 3 years! It may be a great product if it ever reaches the market, but they have been dealing with production issues, machining issues and who knows what else.
The best you could hope for right away is the OD 4 speed gearset that fits into the 833 case. It is cheaper than the GV deal.

 

[Meep-Meep]

Thanks to everyone so far for their replies and interest... looks like a few people debating the same switch out.

Meep I'm trying to work backwards from what you suggested here... I figured change the gears and see if it performs closer to what I'm looking for then select a cam to make up where I feel that drivability may be lacking... I know cam selection involves the drivetrain choices so why not select my gears which (essentially) should be an easier choice (there's sure as hell less options!!) then match the cam up to my final decision?

I suppose you can do it that way. If you set your goal for the 1/4 mile and make adjustments to maximize performance either with a cam change, gearing, car weight, etc.. you can get there. Just look at the most cost effective solution.

If you break down the performance levels into three categories you can really zero in on a combo. Generally speaking #1 is stock; #2 street / strip; #3 is race. This falls in line with cams, where a 115 LSA cam is very much on the stock side, 112 LSA is street /strip and 108 is race. The difference is the shorter LSA makes the highest peak torque but has a pretty narrow RPM range, and that typically requires low gears and high stall converters and other race parts. So pick your desired category and see what you are missing or need to add.

 

[Ghosty]

Available soon.....HA !!!
That transmission has been in devolpment for over 3 years! It may be a great product if it ever reaches the market, but they have been dealing with production issues, machining issues and who knows what else.

They supposedly started building them this week finally:

http://www.forbbodiesonly.com/mopar...oing-to-production-next-week&highlight=passon

LONG waiting list though. Hopefully we'll get an update from someone who's called them.

 

[Meep-Meep]

I spoke to Jaime about a month ago and he said they had test units in cars for a year. Not sure what the hold up was but it didn't sound like smoke and mirrors.

 

[Ghosty]

I'd be curious how long they think it'll take to crank out 300+ units...

 

[Kern Dog]

I spoke to Jaime about a month ago and he said they had test units in cars for a year. Not sure what the hold up was but it didn't sound like smoke and mirrors.

Most of us probably know about the Infamous Dodge Aspen and Plymouth Volare. Chrysler corp took what they learned from years of building solid, reliable cars and then tossed it out the window. These cars had minimal R & D because Chrysler was starting to lose money, so instead of keeping the engineering models of these cars IN HOUSE to weed out the defects, Chrysler released these turds to the public. The result was thousands of pissed off customers. The cars rusted easily. The carburetors were crap. The "Lean Burn" ignition system was a POS, the cowl areas cracked, the K member moved weight waaaaaaay forward. They rode terrible on rough roads. THESE cars replaced the longest running, most affordable and reliable car line the company ever produced... The A body. It was like having Anthony Wiener follow Ronald Reagan as president.
Maybe Jaime is trying to avoid the same thing. If so, I give him big respect.

 

[Cranky]

It was like having Anthony Wiener follow Ronald Reagan as president.
Maybe Jaime is trying to avoid the same thing. If so, I give him big respect.

I agree and the Anthony Wiener line is funny!

 

[tallhair]

Available soon.....HA !!!
That transmission has been in devolpment for over 3 years! It may be a great product if it ever reaches the market, but they have been dealing with production issues, machining issues and who knows what else.
The best you could hope for right away is the OD 4 speed gearset that fits into the 833 case. It is cheaper than the GV deal.

Has anyone run an OD 4 speed gearset with a Big Block and if so what was your opinion of actually driving it behind an RB in a B body and with what gearset? Factory 4 speed O.D. vs Passon

this from Passon

Shortcomings of the
Original Chrysler Overdrive:
•Inherently weak due to the undercut mainshaft in the 3rd gear
and 3-4 synchronizer area.
• Limited to a 23-spline input shaft (weak spot in a high
horsepower applications)
• Floating countershaft in case
• Lack of evenly spread gear ratios
• Lack of a well matched 1st gear ratio

 

[Meep-Meep]

Most of us probably know about the Infamous Dodge Aspen and Plymouth Volare. Chrysler corp took what they learned from years of building solid, reliable cars and then tossed it out the window. These cars had minimal R & D because Chrysler was starting to lose money, so instead of keeping the engineering models of these cars IN HOUSE to weed out the defects, Chrysler released these turds to the public. The result was thousands of pissed off customers. The cars rusted easily. The carburetors were crap. The "Lean Burn" ignition system was a POS, the cowl areas cracked, the K member moved weight waaaaaaay forward. They rode terrible on rough roads. THESE cars replaced the longest running, most affordable and reliable car line the company ever produced... The A body. It was like having Anthony Wiener follow Ronald Reagan as president.
Maybe Jaime is trying to avoid the same thing. If so, I give him big respect.

The way you summed up the Aspen is what I thought all the auto makers did at some point. Everyone who bought a new car in the 80's was an unpaid research and development technician. And I bet much of that truth still holds today, and not just automotive related.

To me it seems the numbers are not adding up on that tranny but that's just a theory. Meaning manufacturing costs might have gone up during his R&D or changed vendors or something. None of this is confirmed - just me thinking out loud. Jamie did say with confidence and without hesitation that it's a good product and holding up well in test cars. But he's also not obligated to tell me everything.

 

[HYRDGOON]

Ok so there's been some changes and I guess all in all I followed meep's advice and worked out the engine first.

I've ordered a 522 crate from CME Engines breakdown is as follows:

Except for the seasoned and SONIC TESTED 440 block, this engine is all NEW. The block assembly is equipped with Keith Black forged pistons, moly rings, brass expansion plugs, forged steel 4.25" Stroker crankshaft, 4340 forged rods, and premium rod and main bearings. The longblock is further equipped with FFS “STEALTH” Performance aluminum heads, 2.14"/1.81" diameter stainless steel valves, pushrods, valve springs, hydraulic lifters, roller rocker arms, true roller timing set and a camshaft with around .540" lift and 286/236 duration.
It is expertly machined, balanced, blueprinted, plate honed, line honed, and decked. It has been assembled by a highly capable technician and spin tested to check the oil pressure, compression and oil circulation!
To the complete versions are added the oil pump, oil pan, oil pump screen, timing cover, harmonic balancer, valve covers, single plane Edelbrock intake manifold, oil filter, oil filter adapter, dipstick, and spark plugs.
To remove the possibility of “New Engine Bugs”, our complete versions are then dynamometer tested and “broken-in” with the proper carburetor, performance distributor and headers. The actual Dyno sheet from the Dyno printer, not a copy or generic, is provided with the engine. A final crankcase pressure test and oil filter internal inspection is performed.

When used with the recommended carburetor, ignition and exhaust system, this engine will produce over 525 horsepower at around 5300 RPM and well over 625 foot-pounds of torque at around 3700 RPM.

Now with that info, 4 speed, 26" tires what gear ratio should I be running to still give me some streetability (highway driving maybe twice/ yr and plenty of backroads doing about 55mph)