340 duster only good for a couple of burnouts.....

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rigger3006

rigger3006

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72 340 duster, runs strong, can lay down a good set of stripes with 295 m/t's. if i do this two or three times then drive around for about 15-20 minutes it wont even turn them doing a brake stand. not sure if its trans related or not, i dont think its the motor, any ideas?
 
how old is the tune up, plug wires
spark plugs and gap timing
transmission fluid filter , proper tans fluid quanity , old torqenveter, warm tires or low air
trans getting warn out , motor getting hot different roads ,, put on smaller tires if you just want to burn them up lotta variations of above vaccum advance hose leak
 
tune is good, all new top end, i think i'll drain trans fluid and put in new filter, just picked car up last fall and working out bugs due to car being parked since 1992. trans fluid smells ''old'' if that makes any sense?
 
rigger3006 said:
tune is good, all new top end, i think i'll drain trans fluid and put in new filter, just picked car up last fall and working out bugs due to car being parked since 1992. trans fluid smells ''old'' if that makes any sense?
Click to expand...
yes if its all burnt it cant hold the pressure , and if the filter is full of bunk it cant flow
 
I'm sure sitting for nearly 25 years has something to do with it.
 
Hey, I'm just waiting for the video of the burnouts. Or at least a picture of two black lines.
 
Are you saying that if you then shut it off for a few hours, and let everything cool off, then you can start all over again with burnouts and everything; and then it's back to the same old sheit?
That would tend to rule out a lot of things.
 
havent tried a few hours later, just next day, yep, same old ****, right in the beginning stages of bodywork on duster and getting demon race ready, im jumping all over the place, right now too much rain to attempt maybe a 3 hour cooldown
 
well youve got my attention. heres what ive got,original 72 340 block, just installed 302 heads that ran fine on my 318, new lunati voodoo cam and lifters 454/475 lift. stock pushrods and rockers, ld4b and 750 QF slayer, engine pulls to 5000 then starts crappin out, runs very nice below that. its wifes car so i dont beat on it ''too'' hard
 
Well there you go.
Ima guessing you're blackies are pumping up the lifters and then the power goes away. I bet you have zero problems running it under 3000 all day,right?
If true,then you need better valve control;perhaps springs,or seat pressure,or anti-pump-up lifters, or less lifter preload, or shorter pushrods;or some combination of all of the above.The bottom line is control
 
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i dont know if i like that answer,lol,springs are old mopar hp's, they would go to 6700 in 318 with 284/484 cam, maybe new lunati lifters are suspect? that would be easy way out! ive used rhoades and didnt like the noise
 
zero problems to 5000 all day long, even when it wont spin the tires, it just comes up against he converter and when i let off brakes it takes off squealing for about 10 feet and will pull to 5000
 
Well that kindof rules out lash then.When the valves fail to seal, the engine normally stalls when you bring the Rs down, and it takes several minutes or longer for the lifters to bleed down for a restart.
Maybe the tires are crap when cold,heehee.

Ok here comes a test.
With the engine Cool(not cold), run it up to 4000 in first and the run second to 70mph. Run it as hard as you can without wheelspin.Have a helper time the run with a stopwatch.. Repeat.Total the times together. Now go drive it around til it gets tired. Then repeat the test,with the same helper,again two times and total them up. Compare the two results. If the results are the same or very similar, then the engine is still putting out about the same.
But if there is a very significant difference, say 15% or 20%, then either the engine is down, or it is more heavily loaded.
So the first thing to do is come to a stop,slam the car into neutral,jump out and push the car on flat level hard ground. If it pushes easy, at least your brakes are not dragging, and neither are any tranny guts.The reason I mention this is because I have seen front calipers stick on after a bit of driving, but overnight they may release. This is usually pistons sticking after a bit of heat gets into them,but can also be a flexhose problem. I have also traced this to a compensating port issue, and boiling brake fluid.So don't think I'm coming out of left field with the push-test.
You can also do a coast-down test, the same way. On flat level ground, on a calm day,with the cool brakes this time, run it up to 70, and put the tranny into Neutral.Then time the coast down from 65 to 45. No brakes, repeat in reverse direction, add the numbers together.
Then drive it around again til it gets lazy and repeat the coast down test again two more times. Compare the results. The times should be the same or very similar. If they are significantly different, I would immediately stop the car, jack it up and check for brake drag; both fronts. No drag means the power loss is in the tranny or in the rear. So hustle the jack out back, and crank the rear end up. Put her in Neutral and spin the tires by hand. No drag here leaves the tranny or the TC.But a drag here could be in the brakes, the flexhose,the C&P, or the driveshaft.
I can't imagine a drag in a TF but I could imagine a bad TC.
I could also imagine a tranny failing to downshift into first when coming to a stop :(
 
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well theres some stuff to do, front pads and calipers are new, just changed diff fluid and put new grease in bearings, ive got back drums backed off just to see if they were the problem. if i leave house and do a couple of brake stands drums are very hot to the touch. even on a regular drive around town, i live in a very small town(2000),they are quite warm to the touch
 
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