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Discussion Starter #1
All,
Thoughts/opinions welcomed.
Converter: Cohn or TCI. Both are rated 2200 stall. Both are around $350. Going in TH350 auto trans basically brand choice here.

Cam: Comp Cams or Lunati (Somewhat brand choice but some difference). Both are appropriately a “268”
Lunati voodoo: 227/233, 489/504
CompCams extreme energy: 224/230, 477/480
In a small block 350 bored over 0.060 with aftermarket vortec heads. 3.42 rear gears. Not sure on comprehension ratio. Probably 9.25:1. CompCams probably fits comprehension ratio better but Lunati more aggressive. Both are the recommended cam for my set up by the techs at the company.

Bonus question(s): just the cam or the cam and lifters or the whole kit with springs and chain? Or Replace springs but not with ones from kit?
Thanks
 

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My opinion, the Lunati. As long a spring specs on the head are good enough for the cam, no need to change just for brand reasons....seat and open pressure specs.

Both need more than 2200 stall if you want to be impressed when you stand on it.....2800 rpm stall minimum. Coan is better quality than TCI.
Personally I'd go with a custom built unit from FreakShow Performance at that price point....it will behave a lot better than either the Coan or TCI shelf models. Tight 10"/245mm 2800-3000 rated stall, it'll drive just fine and not be sloppy at cruise. If you've never bought a custom converter or ode in a car that has one you really don't know what your missing out on.....its a very noticable difference in usable performance.
The "high stall slips at cruise and makes a ton of heat" myth...
 

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ok found your cam flat tappet for lunati...wouldn't go under 3000 rpm stall...especially on a small motor...their recommendation is a minimum stall...2200 might feel too tight...but that's just me...maybe someone will chime in that runs that cam with auto...I run a 4200 rpm converter and it putts around town just fine...but my powerband is in the 4000 to 7000 range
 

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Discussion Starter #4
Thanks for the thoughts guys. I have a 2800-3000 stall (I think just a cheap, Jegs brand) converter now paired with my more mild cam and just hate how it behaves. Maybe I will like it better with the stronger cam but just don’t love how high the engine has to rev to get any movement. Might change cam and then decide on converter later. I don’t have a manual valve body and think I would like how it drives/shifts better at 2200-2400 stall. Car lives in the 2-5000 rpm range. The cams are what the manufacturer techs recommend with my set up and a 2200-2400 stall converter (didn’t say I had 2800 in now) and vice versa. weird they would suggest more cam than converter could use but maybe they are being conservative. Again, thanks so much for the thoughts. This is a great forum with awesome people!
 

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are you sure your tranny is good not slipping...just because it's a 3000 stall doesn't mean it won't move...stall is torque related...so when barely applying throttle it should hook up at 1200 or less...unless your not giving us enough info about how it's acting...
 

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Thanks for the thoughts guys. I have a 2800-3000 stall (I think just a cheap, Jegs brand) converter now paired with my more mild cam and just hate how it behaves.... I just don’t love how high the engine has to rev to get any movement
I highly recommend to stay away from "off the shelf"..."one size fits all" torque converters. The wrong converter set-up/construction can ruin how your car "feels". A while back, I installed an "of the shelf" 3000 stall converter and hated it. It felt "mushy" and loose under normal driving conditions.

I went with an Edge Racing Converter - "Street Edge" 2800 stall and couldn't be happier. It was custom built for my setup. It feels nice and tight from normal start and cruising... but you know the stall is there when you mash the gas.
It might be worth contacting some of the companies that build custom torque converters to see what they recommend for your goals.

Below is a link to Edge Converters for a Turbo 350 Trans (link also has contact info).
 

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You hate the way your current 2800-3000 stall converter feels because it is a cheap piece, built with sloppy clearances and less than ideal fin angles, thus it feels loose and sloppy in operation.

A good custom built converter will stall like it is supposed to but feel almost no different than a stock converter at mild throttle and cruise, and only be slightly noticeable as throttle is applied from a dead stop or slow corner.
I'm telling you, there is NO comparison to off-the-shelf junk.

You talk to anyone who's bought a custom converter if they are real gearheads and not just street cruisers, and they will all tell you it was one of the top 3 things they ever did for their hot rod.
 

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Or, you can add a third pedal and have fun again.
3rd petal is a waste of time...the right TC much better and easier...just slowly mash the petal till you know it will hook and go wide open...but mine is a turbo glide so only 2 gears...and runs hard on top not bottom
 

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I second the 3rd pedal option for me, personally. I like rowing gears and having an OD. Lunati advised me to go one step lower on the chart to their 262 cam purely because I will be doing long highway cruises and wanted the torque to come on a little lower so I didnt "have" to downshift to pass.

With their 268 cam and your gearing, I would definitely head the advise above and go with a 3000ish stall from a good, reputable builder. The difference between el-cheapos and the real deal is absolutely noticeable.
That 268 deg cam from both the big names is a really hot seller for a reason. Keep the compression as close to 9.5-10:1 as you can and it'll do what you want.

Just a note on springs. Quite a few years ago there were a TON of flat tappet cams being wiped out due to low zddp in modern oils (there's a sticky here about it). Anyway, I truly believe these cam manufacturers are playing it pretty safe when it comes to spring pressure they recommend. If you're rarely going to spin the thing over the manufactures rated RPM then you probably aren't going to have a problem with valve float. If you are, a stiffer spring might be in order. Remember that where that cam operates could go a few hundred RPM either way from what Lunati says depending on the rest of the build.

Maybe someone that knows a little more than I do about how much spring pressure you can get away with will chime in.
 

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Discussion Starter #11
My daily driver is a manual. I wish this one was but don't want to change it from what it is. It will be an automatic without even a manual valve body for the foreseeable future.
I don't doubt that a fair portion of my issues with the converter are due to it being cheap. I will look into a custom converter but still think I won't go much higher than 2600 stall.
Sounds like Lunati > CompCams as far as what I listed
Custom Edge/Freakshow/etc. > Cohn > TCI and 2200 stall too low.
Thanks again.
 

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Get a custom built converter like ericnova suggested. A cheap converter will be way loose on the street. I run a custom PTC converter now. It’s a 9” that flashes to 4-4500. But yet tight when just cruising around. I also have an 8” custom built BTE. Same way as the PTC. Great street manners but will come up to 5000-5200 against the tranny brake.
 
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