CAM AND STALL HELP...wtf???

tlcooper

tlcooper

Member
hey guys. I upgraded to a 3800 (yes 3800) stall converter last september. its in my modded cpi engine. and here the weird thing. when I had my stock cpi cam with specs of 208/208 w/ .432/.440 lift @.050. when I stomp it, it would burn my 20inch tires slam 2 hell. now recently I've installed a comp cam with specs of 224/230 @.050. now it seems like my truck is a dog off the line unless I launch in 2nd gear and up top it feels sluggish accelerating. WHATS GOING ON HERE?????
 
BoostedSUV

BoostedSUV

Active member
Re: CAM AND STALL HELP...wtf???

Sure the cam was degreed correctly? If the cam timing is off, advanced or retarded you can have low end power issues. Initially I would have said the stall is too high on the TC but you ran the 3800 stall with the stock cam with out issues?
 
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tlcooper

tlcooper

Member
Re: CAM AND STALL HELP...wtf???

well the cam was installed str8 up. its a comp cam and it has 4 degrees of advance built in. so would degreeing the cam help? oh I dont have a tune yet, but i do have my cpi regulators fuel pressure bumped up from the normal 60psi to 70psi at idle. my tranny isnt computer controlled so how would a tune help.
 
BoostedSUV

BoostedSUV

Active member
Re: CAM AND STALL HELP...wtf???

tlcooper said:
so how would a tune help.
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well you can't just slap a new cam into a computer controlled vehicle and expect it to work. The ECM has no idea you increased cam lift therefore it will not be the correct tune. A larger cam requires more fuel and perhaps more timing. Everybody thinks they can just throw parts at a motor and expect power gains but unless you tune the ECM to accommodate them you're probably losing power... Not saying that is your issue though. You should probably be running a lower stall TC
 
tlcooper

tlcooper

Member
Re: CAM AND STALL HELP...wtf???

any suggestions? but Ive heard ppl over on s10forum who run a 2400 stall with the comp 270ahr and they say it a dog off the line until it gets into its power band. and my cam is bigger than the comp 280, so what stall speed do u guys suggest?
 
BoostedSUV

BoostedSUV

Active member
Re: CAM AND STALL HELP...wtf???

What are your stall speed numbers based on? Actual stall speed will depend on your specific application and how much tq/hp you have. So what I am saying is where does that 3800 stall number come from?

Personally I would say 2800-3000 max would probably be sufficient but I don't know much about cpi setups.
 
dgoodhue

dgoodhue

BuSTeD 4.3
Re: CAM AND STALL HELP...wtf???

I think your trying to compensate a poor tune with a stall converter. 3800 rpm is already really high
 
tlcooper

tlcooper

Member
Re: CAM AND STALL HELP...wtf???

I got the 3800 stall speed from the 4.3L hotrod mag built. and also thats what atlantic coastal converters recommended for my cam specs: 224/230 duration @.050, .532 intake/.544 exhaust, 114lsa w/ 4 degrees advance built in. my motor is built just the same as hotrod mag's and their dyno numbers showed that the cam really started kicking in at 4000rpms.
 
tlcooper

tlcooper

Member
Re: CAM AND STALL HELP...wtf???

so what do u guys advise. should I get a tune or swap out to a lower stall converter?
 
T

turboj91

New member
Re: CAM AND STALL HELP...wtf???

tlcooper said:
my trruck is a dog off the line unless I launch in 2nd gear

That makes no sense at all.

Changing your stall speed will not cure your problem. If you had a tune for a stock cam and installed the bigger cam and did not change anything else, your problem is in the tune. The launching in 2nd gear thing still would not make sense even with a proper tune.
Click to expand...
 
tlcooper

tlcooper

Member
Re: CAM AND STALL HELP...wtf???

ok understood, so a tune it is. I'll get it done by carolina Auto master's here in the raleigh/ durham area but dang it $400 for a dyno tune. do you guys think it would benefit me to degree my cam, retard it a lil, as opposed to the start up with 4 degrees advance built in?
 
turbodig

turbodig

Active member
Re: CAM AND STALL HELP...wtf???

I guess I didn't see it in the post anywhere... what intake manifold and ECM are you running?
 
tlcooper

tlcooper

Member
Re: CAM AND STALL HELP...wtf???

im running the stock cpi intake and the stock ecm. Im definetly getting it tuned but I need 2 know is the stall a real problem or can I get the converter lockup tuned to anywhere I want it even though I have a 700r4 (4l60) and not the 4l60E. my tranny is non computer controlled but I hear that the converter lockup is still an ecm feature, is that true???
 
tlcooper

tlcooper

Member
Re: CAM AND STALL HELP...wtf???

custom comp camshaft:

4.3L full hyd roller
grosse valve lift: .538/.534
duration @ .006 tappet lift: 274/282
intake center line: 110
duration @ .050: 224/230
lobe lift : .3590/ .3560
lobe separation: 114 w/ 4 degrees advance built in
 
turbodig

turbodig

Active member
Re: CAM AND STALL HELP...wtf???

tlcooper said:
im running the stock cpi intake and the stock ecm. Im definetly getting it tuned but I need 2 know is the stall a real problem or can I get the converter lockup tuned to anywhere I want it even though I have a 700r4 (4l60) and not the 4l60E. my tranny is non computer controlled but I hear that the converter lockup is still an ecm feature, is that true???
Click to expand...

Did you do anything to add additional fuel? The CPI injector won't support a whole lot more than the stock HP levels.
 
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