what torque converter??

[jprather]

any suggestions?? 72 Sat sebring plus, 400 4 bbl, slightly built, 8 3/4 3.55 sure grip.. i'm thinking 2000 /2100 stall .. any suggestions on which one you use? brand / stall speed?

i drive in the city a lot, so i think 2400 + is not suited well for stop and go...

 

[rlem1977]

any suggestions?? 72 Sat sebring plus, 400 4 bbl, slightly built, 8 3/4 3.55 sure grip.. i'm thinking 2000 /2100 stall .. any suggestions on which one you use? brand / stall speed?

i drive in the city a lot, so i think 2400 + is not suited well for stop and go...

My suggestion - call a reputable local transmission shop, or TCI, B&M, etc., and ask for a recommendation. Here is what they will want to know:

Engine: size and horsepower
Carburetor: Size
Camshaft: Lift (in) and Duration (@.050 in)
Tires: Size and Overall Diameter
Rear Differential Gear Ratio

Its not rocket science, but with the wrong converter your hot rod won't be able to get out its own way.

 

[wyrmrider]

Stock HP converter with cam 210-222 @.050
Stock big converter with stock 400 cam 204-214
if you have a torque cam then rv converter- I have with 4.60 lift cam works great with 3.23 gears or higher ratio (lower numerically) 355 you can go a little looser
if you have a fast acting cam post back
is this a low compression 400? then HP converter even with short cam

 

[jprather]

i honestly dont know ANYTHING about cams, but this is what is in it, the bottom end is a stock low compression 400
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1496&sb=2

Description

Return to Store Item
Part Number: Grind Number:

Lifter Type:
Engine Family:
Description:
Cam Family:
Specifications Intake Exhaust
RPM Range: Valve Lash:
Valve Timing: Duration:
Lobe Separation: Duration @ .050" Lift:
Intake Centerline: Valve Lift:
Lobe Lift:
Valve Timing @ .006 Lift:
Exhaust
Closes 41
ATDC
Opens 76
BBDC
102

Intake
36 Opens
BTDC
63 Closes
ABDC
Recommended Components
Component Part Number
Complete K-Kit K21-600-5
Cam & Lifter Kit CL-Kit CL21-600-5
Lifter Kit 822-16 [61] / 867-16 [37]
Timing Set 2104 / 3104
Rocker Arms 1621-16 [23] / 1071-KIT [23]
Valve Springs 911-16 / 925-16 [2]
Steel Retainers 748-16 / 741-16
Valve Locks 627-16 [26]
Valve Seals 505-16 [2]
Camshaft Break-In Lube 159
Installation Notes (These notes apply to the above recommended components with the trailing installation note numbers)
Note Description
2 [2] Requires machining on cylinder heads.
23 [23] Includes special shafts & spacers.
26 [26] 1/2 set 2 groove; 1/2 set 4 groove.
37 [37] Adjustable valve train required.
61 [61] Pre 1968 use 824-16 lifters.

 

[wyrmrider]

listing came through sorta blank so I looked it up Thumper
essentially a 280 degree class cam grind number 279TH7 which I don't recognise
279 296 @006 seat degrees intake and exhaust
486-473 lift
107 lca in at 102
the 107 gets the intake closed earlier shows 63 degrees After Bottom Dead Center
Hughes Whiplash style cam timing without the lift
Bigger cam than comp 270H magnum

this intake close point is about the same as a XE275HL
Anyone with experience on converters with low compression 440 and similar cams and rear gears speak up

what converter do you have now and how does it drive- what do you want more of?


tough choices looser converter to make big cam and low compression work but tight so not to slip around town

 

[jprather]

Just put the near rear end in it, has stock converter in it now, but.. i have not driven it.. had trans leak, my mechanic says it is leaking at torque converter and it needs to be changed, so.. while it is out....trying to decide if stock or sumthin in the 2000 / 2100 range

 

[wyrmrider]

Just put the near rear end in it, has stock converter in it now, but.. i have not driven it.. had trans leak, my mechanic says it is leaking at torque converter and it needs to be changed, so.. while it is out....trying to decide if stock or sumthin in the 2000 / 2100 range

That's a seal and maybe a bushing at the same time
most likely nothing wrong with the converter unless the nose is tore up
see if it's a 10 3/4 or a full sized converter
and report back
I'd sure drive it with a stock HP 10 3/4 converter to get a baseline
you may need to jump but How high?
later 400's and 440's came with the smaller converter from the factory
IDK what you have now

 

[Xp29h]

Call these guys. Many good companies out there, I had great luck with them! Have all your info ready and they’ll give you the info!

https://revmaxconverters.com/

Good luck

 

[727]

Tread lightly, It is easy to overcam a low compression engine.
The vert attached will need the smaller stock 10" flex plate. It also will need to have the balance weights attached for a cast crank ( if you didn't swap for a forged one) ask the eBay seller to attach them or buy a set of weight through Jegs and weld em on yourself.

 

[Yatzee]

any suggestions?? 72 Sat sebring plus, 400 4 bbl, slightly built, 8 3/4 3.55 sure grip.. i'm thinking 2000 /2100 stall .. any suggestions on which one you use? brand / stall speed?

i drive in the city a lot, so i think 2400 + is not suited well for stop and go...

The add of a converter posted by 727 is a piece of junk and the advert is somewhat misleading. First off it's not "high stall" at 2100, second there's no brand name or manufacturer mentioned, third a 6 month protection and "call" charge is ridiculous and fourth I must have been hosed because my PTC cost me $700. But my performance went up and my highway mileage did as well with no overheating of the tranny or creeping at idle. Guess I'm one of those "born every minute" with no complaints.

 

[HEMI-ITIS]

Lenny @ Ultimate converts has done more MOPAR converters than I see who did them.
I might send him my Pro Torque for tweeking!!

 

[451Mopar]

On a budget, I usually just get a stock rebuilt Hi-Stall converter from Transtar or other local rebuilder. Ask your transmission guy. You need one with the same balance weights, but I'm not sure what number? Maybe a CR23H? Most of these 11" converters (10" bolt circle.) are in the low to mid 2,000 RPM stall range.
https://www.transtar1.com/TranstarI...que Converter Catalog/mobile/index.html#p=659

Found some info, '72 400 uses the CR17 12" converter, stock stall 1900-2200? (likely less with the larger cam?) Has two 1.40" x 0.750" x 0.250" balance weights? Maybe about 68 grams of balance weight?
The '73-76 400 uses the CR21 11" converter with a lower rated stall of 1800-2100? It has the same balance weights as the CR17 converter above.
The '77-up 400 uses the CR23 11" converter in either Hi Stall (2400-2500) or Low Stall (1900-2100), but uses a 100 gram? butterfly shaped balance weight.

 

[wyrmrider]

way to go 451
OP may have a vehicle where the converter has been changed from OEM sometime in the last 35 years
I'd advise to pull the trans, see what's there, change the seal if the converter nose is ok, put it back together and road test for a baseline
not only stall but how does it react when you try and pass someone
thanks for saying that a big cam can reduce stall
no use paying good money twice

 

[727]

I think this engine doesn't need anything more than a rebuilt stock 10" converter.

 

[wyrmrider]

most likely
give it a shot

 

[moper]

If it was me, I'd replace the camshaft. One of the caveats of the Thumper design is a drop in lower end power. They recommend a performance convertor and with a stock piston 400 - it needs going to be sluggish. I'd replace the cam with something more matched to what you have and what it needs to do, then run the factory high stall convertor.

 

[wyrmrider]

good observation MOPER
Well his thumper is a 227 intake 241 exhaust 279-296@.006 I do not see how he needs that much exhaust Intake closes 63ABDC
but the 107 lca allows him to install on a 102 Intake Center Line and he could go down to 100 to get intake intake closes 61ABDC
let's compare this chevy master grind with the MOPAR XE275HL which is shorter 231-237 275-287 but gets .525 lift Intake Closes 64 ABDC
so low end is going to be about the same and HL should out power Thumper

only solution besides installing the Thumper at 100 would be to get the XE-HL ground on 107 instead of 110
or use a shorter lobe to start out with
My conclusion is not that the Thumper design hurts the low end it's the size of the smallest Thumper (and why the old school super long exhaust) (stock exhaust or headers- I forget)
Thumper appears to be similar to the Hughes whiplash concept- lots of ways to skin a cat It's a feature for the rump rump or a crutch to get a big lobe in a low compression motor
let's get a converter in the car and see where the stall is and go from there
worse comes to worse he could get that Thumper reground (if there is enough meat on those chevy lobes)
or he could put some high leak down lifters in- that might tame it down Rhodes style lifters
lots of ways to skin a cat -

 

[BSB67]

Just put the near rear end in it, has stock converter in it now, but.. i have not driven it.. had trans leak, my mechanic says it is leaking at torque converter and it needs to be changed, so.. while it is out....trying to decide if stock or sumthin in the 2000 / 2100 range

1) Find and fix the leak. Like mentioned, very unlikely it is the converter.
2) Drive it with the converter you have now and check to see what size it is.
3) If it does not work out with the converter you have now, You should then take your info to a converter guy and see what he recommends.

I know that these cams are pushed on guys that want to get more out of their low compression motors, but they do have consequences. If you like the idle and low speed operation of this cam, great. But a cam with 74° overlap in a low compression short stroke 400 for city driving might not be everyone's cup of tea.

 

[BSB67]

107 lca in at 102
the 107 gets the intake closed earlier shows 63 degrees After Bottom Dead Center

Anyone with experience on converters with low compression 440 and similar cams and rear gears speak up

61.5° ABDC

Not sure a 440 would be a good comparison to a 400 in terms of torque converter selection IMO.

 

[jprather]

WOW, !! i am overwhelmed with all the info !! thats why i love this site !!, it is the original flex plate and torque converter, i dont race, i just like the way the cam sounds with the cut outs open