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Overdrive automatic options

Bighouse

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What’s available?? My cars a 340 small block.
 
Not a fan of the gear vendors- looking for transmission options
 
Silver Sport Transmissions has the 4 speed automatic based on the GM 700R4, also known as the 4L60E.
 
I think the 90-95 were hydraulically controlled similar to the 727(h designation) the re is electronically controlled. There is an aftermarket kit to retrofit this into other cars. The 2wd versions are not easy to find. I'll be doing a rebuild for a friend's street rod this winter. Had to get it from an early 90's Dodge van.
 
518 or 46rh need only 12 volts to lockup converter and 12 volt to engage overdrive. There maybe a computer. But all that is needed us a couple pressure switches and simple wiring. I believe the trans will bolt right up to your 340 with a correct weighed converter.
 
The 518 will require a redesign/modification of the top area of the torsion bar/transmission cross member due to the size of the extension housing.
Mike
 
The 518 will require a redesign/modification of the top area of the torsion bar/transmission cross member due to the size of the extension housing.
Mike
I haven’t installed one in a B- body. But it appears that most get away with a simple grind of a rib or two on the OD case.
 
There is a couple of pressure switch kits for the three-pin lockup model for around $100.00
G.V. costs way too much and you don't get a lockup.
 
There is a couple of pressure switch kits for the three-pin lockup model for around $100.00
G.V. costs way too much and you don't get a lockup.
It will handle a couple thousand horsepower though. You can't put much through a 518.
Mike
 
John Cope has 518 setup that sounds good. He has a YouTube video on his product!
 
Don't forget to consider linkage.

I put a Gear Vendors in my 340 (now a 416 stroker) with a 727 and a Slap Stik shifter. The floor shifters have linkage that bolts to the transmission tail housing. A GV unit replicates this mounting system so you can use all stock parts. If you go with a 518 I don't think you can connect your floor shifter without modification. Not sure how hard this is but still something to consider.
 
Hi, this website, PATC, Performance automotive transmission center, is a great place to read and understand installing a 46RH/A518 transmission. I’m doing a 2nd gen. Charger with a big block with one of their 46RH transmission Products. The good thing about your application is you can bolt the 46RH/A518 right up to your small block without any modifications to the transmission it self. This Direction in an overdrive transmission may not be everyone’s cup of tea. This is just a form of making the decision for the direction for your project. Good luck
 
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