4L60 Re-Rebuild for my C20

[LTZ C20]

http://monster-transmission.pissedconsumer.com/

That sucks. But, it is a ferd lol.

[Irish_Alley]

stock stall depends on the motor for a 350 it should be the low stall 1400ish

[LTZ C20]

Ok. How about a 350 producing roughly 360-375hp & 400-425ft lbs. Has roller cam and is tbi.

[Irish_Alley]

im not an expert in this and this is only my opinion. but if you want the better mpgs go with stock, if you want to reach your power band faster go with a higher stall. if you dont plan on racing anyone go stock even if you do race stock wont really hurt you and i wouldnt care unless i was trying to win money. my cummins wants/likes the 1200 stall vs the 1400. but my power band is much lower, for a sbc i would op for the 1800.

[LTZ C20]

Race no. It's not a racing truck. It a hauling and towing truck. Mpg's I would kind of like better but not really. I mean better mpg's is always good but the truck has the aerodynamic properties of cinder block so I don't really care. I will probably get better mpg's just being able to get the truck up and moving quicker with a higher stalls right? More efficient use of available torque? I think get up and go power with a heavy load will be better also with a non stock converter, not as much wasted torque?

[bd]

OEM stall should be about 1300 RPM.  Hughes makes a decent converter; I ran one for several years and was satisfied.  What's the CFM of your throttle body, what are the cam specs, what axle ratio and tire diameter?  Without naming names, be guarded and do extensive research when purchasing aftermarket performance transmission hard parts.  As tempting as it is to believe what you want to hear, keep in mind that companies are driven to sell their wares.  If something sounds too good to be true....

What does your transmission tech have to say about converter stall for your application?

[Irish_Alley]

What does your transmission tech have to say about converter stall for your application?

this would be a very good step.

[LTZ C20]

Ok 1300. That's a solid number to work with. Good to know Hughes are decent products.

Throttle body cfm is 670. Stock cfm for a big block TBI. At least that's what I was told.

Cam is Comp Xtreme Energy, OE roller cam 1987-2002 sbc 305-350, 1200-5200 range, lobe sep 110, intake centerline 106, duration 264 int 270 exh, duration @ .050 is 212 int 218 exh, valve lift is .487 int .495 exh, valve timing .006.

Axle is 4:10 with 265/75R16 tires.

I want to make a careful and informed decision for 3 main reasons. 1, these things are expensive! 2, I want to do what is best for my engine, trans. Don't want to rebuild it a 3rd time. 3, if I just pick one and I end up for whatever reason finding that I need a different one, these are a PITA to just "swap out A for B".

[LTZ C20]

What does your transmission tech have to say about converter stall for your application?

this would be a very good step.

He knows I plan to tow with it and he rode in the truck with me, so he knows it has some decent power. I told him I've been poking around at converters. He said "I'll get you a price on a stock one." Not sure if his recommendation is stock unit or if that's simply the ones he can get thru his supplier. He has built hundreds of these working at independent transmission shops, I would be hard pressed to believe they have all beenough stock. I'm going to run these 4 options by him tomorrow and see what he says. He did say stock shouldn't be more than $200.

[Irish_Alley]

if you tow i would also go for a lower stall. the more of a stall the higher your trans temp will get and this an kill the trans fluid.

[LTZ C20]

if you tow i would also go for a lower stall. the more of a stall the higher your trans temp will get and this an kill the trans fluid.

That seems to be the general consensus for towing applications.

[bd]

So, you're using the Comp 08-412-8 with a 670 CFM dual throat throttle body.  With the Dart heads, I'm supposing that combination should come alive around 2100 RPM, with torque peaking around 3000 and HP peaking ~5100 then dropping off quickly.  Does that sound about right?

[LTZ C20]

Sounds just about spot on actually. It pulls with the most muscle from 2000-3500. Not sure where hp peaks at, I've never pushed the new block passed 4500.

[bd]

From a hot rodding perspective I think an 1800+ RPM stall would fire stoplight acceleration.  BUT, considering that you want to tow and haul as well, you would be better off with a stall RPM proud of 1400.  In addition, I recommend a B&M 70274 cooler plumbed through ATI 925138 fittings and -8 AN line.  You could add an inline spin-on filter to keep debris out of the coolers and converter in case of a subsequent failure; a temperature sender could be mounted conveniently in the filter base.  Synthetic fluid also is a good idea.  Just an opinion.

[SkinnyG]

Talk to a Hughes rep - they ~do~ know their stuff.

I contacted all the major converter manufacturers when choosing mine, and I was the most impressed with Hughes customer service, and their recommendation for me was spot on.

I'd say for towing you want a fairly low stall.

I have a 2500 converter, snotty cam, and deep gears.  Hughes says absolutely no towing for me, says I can't have the converter the cam needs, AND pull a trailer (which is fine for me).  Too high a stall with too heavy a load, and the heat will destroy the trans.