I already have a 2000 stall converter and i am told it's not large enuff. I am not disagreeing but i would like to know why it's too small. Anyone care to explain what i am missing? If my cam rpm range is from 2000 to 6000 rpm what stall speed converter do i need and why.

[This message has been edited by mwcox (edited 03-02-2002).]

basically your cam converter and gears have to be matched to perform optimaly.
Since you want a cam with close to 248 duration at .050", and i'm assuming some decent sized heads and a single plane intake.
Your powerband will be somewhere in the range of 3500-7000 rpms. you should peak torque at about 5500rpms, so optimally if you were racing you'd need a 4000stall, but this is rediculas for the street.
Anyways the 2000 stall you have now is not in the correct range that the cam needs, the converter needs to slip a little bit so that the engine can get going without a load and they take off once it gets to a speed where it'll launch.
It's tough to explain, so i'm trying my best here.
Your gears are also important to this, you'll need something in the range of 3.73-4.56 for the gears, it takes more rpms to get to a certain speed with bigger gears, so that'll put the engine in its power band.

This is to your advantage and to your disadvantage. More RPM's make the converter slip less at a given speed becuase your turning more rpms,. also bigger gears make more torque, to make up for the low end torque loss of a big cam.

You'd need a converter in the range of 3200-3500 to remain streetable and keep the car in its powerband.
ATI makes excellent converts that can have a stall like that, and wont slip as much as say a B&M or TCI or similar converter at a given speed. They also cost a little bit more, but they're worth it.
Less slip means less heat which means your tranny lives a longer life.

The other thing you could do would be to keep the cam as small as possible that'll still give that lopey idle that you want.
From what i've heard the Comp 282S magnum solid will shake the earth, and is still streetable, although you'd still need a converter in the 3000-3200 stall RPM range.

Yes,yes i totally agree with everything you have said but i think what is escaping everyone is i am not going to put in a cam with 248 @50 it will be more like in the range of 224 to 230 @ 50. Does the 282s boast a 248 @ 50? That would seem like alot more adv. duration than 282 degrees.

[This message has been edited by mwcox (edited 03-02-2002).]

In a pure racing situation, with optimum traction, I've read that you want your stall speed to be 500rpm short of your peak torque. Now, given we're dealing with a street car we have to compromise(unless your crazy http://www.camaros.net/forum/wink.gif) Honestly, I think the cam your talking about would work ok with 2400-2800 stall. I wouldn't go any lower. If possible I'd go higher, more in the range that CnC has been suggesting. I believe you'll be greatly disapointed with your car with a 2000rpm stall.

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79' Z28 4-spd- built 355, TRW 10:1 forged flat tops, WP SportsmanII heads, Crane Energizer 230/230 duration .480"/.480" lift, Edelbrock Victor Jr., Holley 750cfm, Dynomax headers, dual 3" flowmasters :) 3.73 Posi 10-bolt

Hey camaro,I dont think it would require a 3000-3200 stall to use the 282(although it would be more fun!). He could get away with a 2200. My comp cams catalog sais 2200+ stall for the 280H which is the brother of the 282S. Two things happen when get up to a 3000 stall, first thing is the price gets a bit spendy for a 3000+ stall compared to anything below it. The second thing is more heat with a high stall. mwcox,you really would enjoy your ride better if you went up a bit with your stall but you may be able to live with the 2000.

if u check out this months of chevy hiperformance mag it has a full tech article on it if u dont want to buy it i can scan it for ya

Something that you guys are forgetting is that a solid cam has a valve clearance and because of this you will lose lift and duration. Because of this the cam acts milder then what you would think. Solids also tend to come on the cam a little sooner. Most manufacturers recomend that you take 6 degrees off when comparing a solid to a HYD.

I would think that a 282s wich has 236 .050 duration would survive with a 2400-2800 stall.

When it comes to Comps power ranges, don't believe them, they over rate it. I believe that it inables them to sell more cams. You should take there low rpm range and add 500 rpm and use this as a bare minimum for your stall speed.

I have had a 350 with a 280 Magmun and a 2400 stall. It was...Ok. If you nailed it and watched the tack, you could tell that the motor realy came on at around 2700-3000. Not the 2000 they say. In fact I have seen a dyno sheet of a very similar motor with the same cam that showed the motor to be kind of a dead player until 2750 and at 3200 it realy came on.

They should say (when it comes to the 280 Magnum) "You can get away with a 2400 stall as a bare minumum, but a lot better performance will be had if you use a 2800-3500 stall".


[This message has been edited by mutant 68 (edited 03-02-2002).]

i was under the impression he wanted something in the 248 duration range.
In which case, he wants the 282S instead which is 236 duration at .050", going by what you guys are saying that's going to be 230 duration after we factor in lash.
Now this cam will probably peak torque at 4000-5000rpms in most street engines.
In which case you could probably go 1000rpm below peak torque on this for the stall, which is 3000rpms, and this would make for one hell of ride!
I understand that this probably adds a big expense to the plans, but seriously consider it if you want the lopey cam, or i think you'll be dissapointed when you stomp on it.
Just take into consideration ATI's streetmaster converters, supposedly tighter then there treemasters, which are also a tight converter. they sell them in 10" 3000-3500 stall (they help you pick it) and the cost is: $423, not bad at all.

Mutant 68 is right on. I'll add something else to it. If you look thru a comp cams catalog you will notice that on the cams that they recommend a convertor on they will list the minimum stall speed as the bottom of the listed powerband plus 400-600 rpms. For a 2000-6000 rpm cam, consider a 2400-2600 cam to be the minimum. My xe268 is listed as a 1600-5800 rpm cam (if I remember correctly). It is ok with a 2000 stall but really comes alive after 2400-2500 rpms. A 2400 stall would make a lot of difference in my application, but due to gearing, weight, and intended useage, I don't want anything more than the 2000 thats in there.

It's the age old two-part question:
How much cam can I get away with?
How low of a stall speed can I get away with?

Spend your money on a quality, purpose-built converter, not the bargain basement re-hash from some big-name advertiser. I run a Precision Industries 9.5" Vigilante converter that stalls at about 3800 rpm behind my 406. This converter doesn't slip much at part throttle, I can accelerate at a moderate rate without exceeding 2500 rpm. When you apply the torque to it, it immediately goes to the stall speed and you are underway in a hurry.

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1967 Nova coupe daily driver
406, 10:1, 224° cam, Q-jet, 700R4, 3465# w/driver
11.76 @ 116 thru the mufflers
18 mpg on the road

}I already have a 2000 stall converter and i am told it's not large enuff.

Let's fall back a minute. The above information is very good and valid. But how do you know your current converter stalls at 2000 rpm? Did you verify this or "did you hear this from somewhere".

Does your car work now? I'll bet it does.
Did the person who said your stall converter is too low happen to be in the parts selling business?

You know stall converters true stall is based upon the torque of the engine applied. So if you have a 2000 rpm converter, it might stall anywhere from 1800 to 2400 and you're all set already.

But take the above information to form a better idea if you can justify spending $500 and possibly not have anything beneficial happen to your car. If your car was a dog off the line or acted sluggish and you said it had a big cam in it, then you'd have to upgrade the converter, but right now, I doubt it.

he's switching to a big cam, he doesnt already have one. imo even 2400 is small for a 282S cam, i'd go 2800-3500. ATI, Coan, or precision industries make great converters.

I realize that. When he does the cam he'll be prepared to also buy a compatible converter. My main deal was to point out a lot of people do things "because". And we're all doing the right thing by discussing the "why".

One thing to also do when you upgrade the converter is to put a transmission cooler in the car as well. The increased stall of the converter raises the temperature of the transmission fluid. And heat is what'll smoke a trans pretty quick.

oh ok, from the way you worded it i wasnt sure you knew that he didnt have it in already, sorry.
Your right, he will need a trans cooler, spend your money on a good one. and remember to route it into the radiator inlets too so that it can warm up the trans also. a cold trans is as bad as a hot one, they require a certain temp range.

Extrapolating on the stall speed a little further, more cam means less torque at low rpm's, so a 2000 stall converter with a 220° cam will be somewhat less with a 230° cam. I don't know how B&M rates their converters, but I'll bet they use a very torquey motor to get the stall figures.

Now that the opinions are in and i now have a better understanding of why i need a higher stall speed my order will be going off tomorrow for a ati 3000 converter. I already have a external cooler installed for the tci transmission. All the engine componets are brand new including the 4 core radiator and 18" electric cooling fan. My ring and pinion is a 3.55 8.5 10 bolt posi unit that has been narrowed 3" per side and the car was mini-tubbed this past summer. Thanks for all the good advise and information. I sold my 2000 b&m today to a friend to go into his truck that he uses for towing his modified to and from the track so it has found a good home. The cam i settled on was the comp. cams 276s solid. This should provide me with exactly what i am looking for, good sound and drivability. Thanks again to all.

make sure you talk to the guys at ATI, and they'll make up exactly what you need, from what i hear they're a good bunch.
glad you decided on the new converter, you'll love it!
on all of us here, glad we could help you.

[This message has been edited by CamaroNOTcamero (edited 03-03-2002).]

Just be prepared....For sure what you think you need, will almost certainly be tossed once you get hooked up with the guys at ATI.
They will be in line with onovakind`s thinking, more so than some others on this subject.
What "you think you need" may not be what you really need.
Let us know what they have to offer, it should be interesting.


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78 Camaro hyd cam 406
TH350-3.23 gear
11.86 ET
116.7 MPH

I know there are a lot of people that disagree with this but as long as your car will idle at a decent rpm and not pull on the tranny when its in gear, your OK. the rest is carb, cam, gearing and traction. A bigger cam will idle irreqular and need more stall to idle without tearing the tranny up

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69 convertible
LT1 4L60E

in my 69 383 stroker I bought the car and the guy said it had a 3000 stall in it.I know jack about any of it except at 55 mph im taching out at 3 grand. Its fine for around town but on the highway 50 to 55 aint cuttin it.It also has the crane rev limiter on the firewall if that has anything to do with it.Just my 2 cents worth and maybe someone out there can explain all these bells and whistles to me too.Mechanics around here just stand around the car with their mouths open.

Bakerdude- That's likely your gearing, not your converter causing the high rpm's at highway speed. Sounds like you got a DEEP gear. I have 3.73's and pull 3000 @ 65mph.

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79' Z28 4-spd- built 355, TRW 10:1 forged flat tops, WP SportsmanII heads, Crane Energizer 230/230 duration .480"/.480" lift, Edelbrock Victor Jr., Holley 750cfm, Dynomax headers, dual 3" flowmasters :) 3.73 Posi 10-bolt

is it ok to drive it like that and what do they mean when the stall kicks in? jim ex mines a 3000 stall you mean it doesnt kick in till i hit 3 grand?

if you need to reduce your freeway rpm go to a taller rear tire.

wow red69camaro
from buffalo thats sweet im right in niagara falls maybe we can hook up sometime at k&s
or just email me


ohh yeah if u still want to see that tech article in chevy hiperformance get it now or i can scan it for yah its 2 pages on converters

276s AY. My guess is that ATI will tell you to go with a tight 2500, especially with the 3.55 gears. This should prove a very enjoyable cruiser.

<BLOCKQUOTE>quote:</font><HR>Originally posted by bakerdude:
is it ok to drive it like that and what do they mean when the stall kicks in? jim ex mines a 3000 stall you mean it doesnt kick in till i hit 3 grand?<HR></BLOCKQUOTE>

Stall doesn't 'kick in', stall is what your engine does when the torque of the engine is insufficient to accelerate the converter pump against the locked turbine. If your engine produces enough torque to run the pump at 3000 rpm with the turbine locked, it is called 3000 stall. The converter actually works at much lower rpm's, but the converters designed for higher stall speeds will spool up quicker to the higher speed.