Most cost effective transmission build for 600 or 700hp turbo drag car

[furious70]

While I've been planning a turbocharged 5.7 gen III for my Coronet, it's been waiting to go into the body shop and I stopped working on that to focus on my Fury. In those 2 years the prices and availability of drop out hellcat engine/trans assemblies has continued to come down. Catch the right one and you can get the whole thing, sometimes including the IC cooling system and engine radiator for $11-13k with many advertised and not selling at 15k. Add $2k to handle the electronics but it's a 717hp package with room for more (the Power Brokers are going to have s/w kits that go to 757 I think)
5.7 take outs have gone up in price, around $3-4k. I already have my turbo, already have a 392 cam for it. Hard parts (piping, etc) at least $1k plus my free labor (though I enjoy building turbo setups). $2k for electronics as well. But I have nothing for a trans but a sb 727 core.

What am I realistically looking at for costs to have someone build a trans to hold 600hp in this market? 700hp? Plus the converter for the boosted application? (I would just run the OEM converter to start at least in the hellcat option).

Trying to sort out just how expensive the 'cheap route' is vs the drop in hellcat.

 

[rolling_Thunder]

5.7L hemis can be found for relatively affordable prices - even the 2009+ Eagle headed ones. For Transmission you can go with a built 727 with no OD to keep the price down - or you could even go with a dime-a-dozen GM 4L80E and have a huge aftermarket support and electronically controlled. While the Hellcat engine is tempting they are a huge nut all at once - with the piece meal process you can slowly spend what you want over time... obviously this drags the build out even longer.

I am building another Gen III myself - essentially waiting on rotating assembly for a 7.0L build with a Hellcat top end. My goal will be 1000hp on E85 and ~750-800hp on pump. I went the affordable route and went with an MS3X to control it all and backed by a Viper spec T-56 I will be going through and putting some TR-6060 internals into for easier shifting.

 

[furious70]

I'm with you. Not too concerned about spending at once or over time, more interested in the total cost/cost to race it.
If I go 5.7 the most cost effective is late model Ram with electric ps as the belt routing and engine accessories match what I need and the better lifters are in it. The cost to buy another FMEA setup, even used, and possibly replace lifters on an earlier Eagle makes the price a wash.

Really interested in experiences building 727 for this power level or other options. Someone had put a turbo 400 in their Coronet on here I think. Right now I am fine with a 3spd. I might have dreams of drag week with this car but who knows

 

[MarPar]

 

[493 Mike]

Contact Cope Racing in Indiana.
Mike

 

[dvw]

Doesn't need much. Good valve body. If you're going to run a trans brake a steel front planet carrier is a good idea. Good front drum is always a good idea. If the valve body is not LBA, a Super Sprag is a good idea. 3.8 or a 4.2 lever, 4-5 front clutch frictions set ay .012"-.015" per friction. Solid red forward band. Later model front drum/reaction shaft is best. Later model rear clutch piston and spring is best.
Doug

 

[Lefty71]

Contact Cope Racing in Indiana.
Mike

THIS..... I do believe John Cope has been working on the solution to the late model conversion problem for a while now.

 

[theman440]

Most times these words - ("Most cost effective transmission build")
are code for besides a Mopar trans - do you want to run a Mopar transmission?

 

[furious70]

I'm open to running something other than mopar, but sometimes the total cost of ownership and knowledge/skills needed don't make the brand X pieces pan out.

 

[dvw]

Get the Gen 3 Hem flex plate and a SB 727 bolts right up.
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Doug

 

[furious70]

Yes, I actually own an sfi flexplate that I got cheap awhile back just to have it if went with a sb727.

 

[Rusty 72]

IMO there is nothing cost effective about a 600-700hp drag car...

 

[furious70]

IMO there is nothing cost effective about a 600-700hp drag car...

It's actually very cost effective vs going faster than 10.00

 

[33 IMP]

I think the most cost effective would be a small block727, with good pieces inside. Doug gave you a recipe. If you are serious about drag week, I would be inclined to go with a 4L80, for the strength and the overdrive. I don't know how much would need to be done to the 4L80 to support 700 or more power, or how much the adapter runs. I bet the 4L80 option would cost double the sb 727.
(Do you think you will be the one guy that WONT turn up the power with a turbo car? Lol). Doesn't a 4L80 need a electronic controller?
(I've budgeted $3000 for a trans with a brake,and a converter, for a 700hp n/a level in my car.)