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Author Topic:   IMCA Hobby Stock tranny & 9"??????
Eagle71
Member
posted November 09, 2003 07:04 PM
I was wondering what to do for a tranny in my Hobby. I have always ran a th 350 and won features. Was wonder what you guys were running to get the most power to the rear wheels. Stick if so what and where to I get a cluth system, th 350, or the glide with the fake converter. Also what provides better bite with gemotry a stock metric rearend or the 9". I'm not worreid about durabilty I just want what works the best thanks


racer17j
Member
posted November 09, 2003 10:33 PM
go with a 3 speed with imca if you try running any dummy converters you'll get busted 80% of the time. and run a z-28 clutch and flywheels that abotu the lightesyt legal set up your gonna find as for the rear end there is no reason i can think of that makes a 7.5 rear end better then a 9 inch take the nine in to a chassis builder that has a jig and you will be able to just bolt it in unlike the stock metric where you have to drill and cut the armes to get everthing right


gould
Member
posted November 10, 2003 06:15 AM
with imca your flywheel needs to weight 19 lbs. then add the weight of the clutch, blowproof bellhousing and the tranny. i thought this would be heavy so i went with a glide. the dummy converters hold fluid so if they tech it just pull the plug and out comes the fluid. i for one cant afford the dummy stuff so ill be using the stock converter.

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Drive it in deep, and come out hard!!


Eagle71
Member
posted November 10, 2003 08:59 AM
Racer 17j The reason a metric rearend won't fit into a 9" jig is becasue the mounts are placed different. When u have a 9" when the rearend is in the car it gives you a lot of trailing arm angle and to much is bad. What I'm guessing is GM made the rears the way there supposed to be with geometry therefore they work better.


dode
Member
posted November 10, 2003 10:16 AM
Eagle-

You use the jig to put the mounts on the 9" so they are in the same position as on the factory GM model, so no there would be no difference.

John

66jj
Member
posted November 10, 2003 10:22 AM
they are no where near stock on a ford 9 inch thats done correctly, with circle track racing in mind.

the top left mount is close to stock ht.
the top right mount is 2-3 inches higher.
the left lower is close to stock.
the right lower should be towards the back of the car a bit to help correct rear steer.

all you need to do to find the correct locations is remove your springs and put your car on elephant stands, and drop the rr 3 and the lr1-2 or so, whatever your getting for travel, and see how unsquare your rearend is in there now!!!!!

racer17j
Member
posted November 10, 2003 06:42 PM
66 is right you put the rear on a jig to get everything set up to turn left and get the proper forward bite gm did not design the metric rear suspention to race on dirt tracks they are designed for a smooth ride going down the road


dode
Member
posted November 11, 2003 10:00 AM
If you have to use stock control arms though, you can't change things around that much can you?

John

racer17j
Member
posted November 11, 2003 06:41 PM
yes you can make the mounts any way you want to get the proper angels on the arms and pinion angle. you'd be suprized how much difference having one upper mount a little bit higher then the other can make


JDF Motorsports
Member
posted November 11, 2003 07:42 PM

I have a scs housing they jigged sitting here and they are different hts. you should look around and see what other people are doing, or just call scs, terminator etc. they sell the mts ready to weld on also.

scs started raising the mts higher on the rs this last winter, or at least on some special people rearends they did.

a friend who builds chassis started re doing all the rearends he could in his cars after he finally took out the springs etc and measured what he was getting for rear steer. I did see more than one of them seem to be much better. I am assuming he just did what I suggested, once a few more people told him the same thing?

[This message has been edited by 66jj (edited November 11, 2003).]

hobby9
Member
posted November 11, 2003 10:30 PM
thanks i'm not a member so i haven't seen the new rules yet but i'm with you it's all about the $$$$$ with imca


TCI
Member
posted November 12, 2003 10:02 AM
"Dummy" converters have become extremely popular within the past year. I don't think IMCA has really been checking that hard for a working converter. The only problem that could arise is if they start checking the temperature of the trans and the converter.

Scott

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Scott Miller
TCI Automotive, LLC
662-224-8972 ext 332
scott@tciauto.com
www.tciauto.com


superdave
Member
posted November 12, 2003 04:04 PM
I don't think the direct drive is the issue as much as the rotating weight and diameter. I watched pretty hard this year to see if the samll diameter direct drive converters (with fluid) were any better than the manual tranny with a Vega flywheel and clutch and honestly they were pretty even. I don't think they belong in the Hobby class. The guy who owns one will disagree with me but ask him if an aluminim flywheel is OK for someone else and he'll throw a fit. The top 4 in season points for us ran the manual setup with no problems. We had winners using both. Parity is the issue not how much they sponsor.

FYI according to the IMCA website Bushore only sponsors the Stock Car class. TCI sponsors Mods, Stock Cars and Hobbys. I'd look hard at who's paying you back before you spend your money. Support the business that supports you.

Good luck,
Dave

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Superdave
______________________
www.salinaspeedway.com


hobby9
Member
posted November 12, 2003 05:34 PM
hobby9 - We do offer those parts for Powerglides and TH-350's. Everything that you will need. Go to our website and look under the circle track section.

Scott

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Scott Miller
TCI Automotive, LLC
662-224-8972 ext 332
scott@tciauto.com
www.tciauto.com


racer17j
Member
posted November 13, 2003 06:58 PM
hey tci what do you have to change to run one of those dummy converters if anything? i'm considering the t-350 setup and what do they run cost wise?


TCI
Member
posted November 14, 2003 08:46 AM
quote:
Originally posted by racer17j:
hey tci what do you have to change to run one of those dummy converters if anything? i'm considering the t-350 setup and what do they run cost wise?

The TH-350 valve body is a bolt in setup. But it is recommended to do a good rebuild on the transmission. Then install the dummy converter and your ready to go!

Scott

66jj
Member
posted November 14, 2003 10:40 AM
TCI,

whats the hp loss with a direct drive glide??
from the pump etc.

whats the hp loss with a direct drive turbo 350??

does the 350 have more internal wt mass turning also??

give us a REASON to go from a manual to a auto.

thanks jeff

TCI
Member
posted November 14, 2003 12:24 PM
A powerglide pulls 18HP in Hi gear. When you lose the converter weight by going with a coupler, your losing on the average of 23-27lbs. of rotating weight depending what size converter your using. When you use a dummy converter, your losing 10-14lbs. of rotating weight. Some people say you can gain 8-10hp per 7lbs. I don't know how true that is. What you are gaining is quicker throttle response because there is less rotating weight. JE pistons says there is no HP gain with liteweight pistons, just quicker response. I think that is more accurate than the HP gain. The weight differences are the same with a TH-350, but it pulls around 31HP in hi gear. You can shift on the fly with an automatic without having to push a clutch in. The TH-350 has more rotating weight than a powerglide, but when you get "technical" with it, the weight is still close to the centerline of the motor just like a glide. Other words its not hanging way out there like a pressure plate,etc. The farther that you get from the centerline of the motor the more the rotating weight effects it.

Scott



66jj
Member
posted November 14, 2003 05:58 PM
thanks lets see if I have this right?

glide -18hp min. direct drive coupler
th 350 -31hp min. direct drive coupler

add dummy converters and the response goes down obviously from the rotating mass.


Am I wrong to assume a manual with no clutch takes less hp in high than both the above, its turning straight thru with no pumps??


TCI
Member
posted November 15, 2003 09:58 PM
With no clutch or pressure plate, just like having a shaft welded directly from the crank to the rear end would be less HP drain. But, we use a lo volume pump which decreases the amount of drag in that area. There is one thing you can do with an automatic that you can't do with a manual - upshift and downshift on the fly without pushing a clutch or anyhting. Just moving the shifter.

Scott

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