That is exactly what was happening. Had to pull throttle open remainder of the way at carb.
Disappointing dyno results
- Thread starter jawbone
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I'm not sure what your saying here. Can you describe in detail what was happening with the throttle?
I agree with you. Too many inconsistencies between pulls and it all points to fuel or carb. Choke is wired open. Secondary air door flap appears to be opening but cannot be viewed during pull due to dyno parts covering top part of carb measuring air flow. Throttle manually opened at carb. Does not open fully with dyno linkage.
Did the dyno have O2 sensers on it at any time? Do you have pictures of the motor on the dyno?
Secondary air flap is opening but if at full open position can not verify. We know throttle plate requires external manipulation to open fully.
Guess he was not the best pick but was the only one I knew with dyno. Looks wore out and not maintained.
I can ask how A/F ratio is calculated.
I think the second test here is going to be close to where it ends, a little more by getting the A/F and timing dialed in, pretty close to factory #'s.
and yet the ET, MPH #'s you posted in other threads represent just a little more HP than the OP's.
dickhead is as dickead does
still 6 cars better then 383dog a body 8 cars for the 383dog b body
Kindof beatin a dead horse but just for reference.
Stock engine dyno with manifolds run by Hot Rod in '69 back by one of the rags, and stock rebuilt engine done more recently by a different mag had very similar numbers. That said, don't expect numbers from one dyno to another to be a real comparison. However shape of curve should be similar.
First three pulls plotted here.
1969 Magazine article with the dyno runs posted here
www.forabodiesonly.com
Stock engine dyno with manifolds run by Hot Rod in '69 back by one of the rags, and stock rebuilt engine done more recently by a different mag had very similar numbers. That said, don't expect numbers from one dyno to another to be a real comparison. However shape of curve should be similar.
First three pulls plotted here.
1969 Magazine article with the dyno runs posted here
Mopar Manipulatin’ , HRM August ‘69
Enjoy the read. Part 2 (Sept. ‘69) coming soon!
www.forabodiesonly.com
If you only knew.
junkyardhero
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old doesn't matter. when i worked at dyno shop our units were from the 70's and performed just fine.
the ability of the operator is the problem here.
linkage all fucky and carb not going WFO? fired.
no scope on the engine? fired.
no EGT or O2 sensors? fired.
no test mule carb, distributor or tuning materials? fired.
you can have the most whiz-bang johnny hot **** computer controlled system in six counties, but if you can't check the carb for WFO and tell that a cylinder is dropped then you ain't worth a ****.
basics matter.
Inertia
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Yeah, I can't get over the dropped cylinder .
I missed the dropped cylinder....
Maybe one of the ring gaps was too tight and broke ( clearanced itself) that happened on my engine due to camshaft installed incorrectly by alot
Maybe one of the ring gaps was too tight and broke ( clearanced itself) that happened on my engine due to camshaft installed incorrectly by alot
autoxcuda
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I believe the dropped cylinder was a burnt plug wire under a shielded boot of some sort. That was fixed the second day.
junkyardhero
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That's all she's got, pushing 275 horsepower with tuning.
autoxcuda
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I’m thinking that 50 year old AVS carb may be suspect if there’s dyno repeatability issues
I know it was rebuilt by woodruff. But what about the throttle shafts, bore wear and other things. Some stuff just doesn’t rebuild 100% like brand new out of the box.
Would have like to seen known good carb tested after the plug wire was fixed.
I know it was rebuilt by woodruff. But what about the throttle shafts, bore wear and other things. Some stuff just doesn’t rebuild 100% like brand new out of the box.
Would have like to seen known good carb tested after the plug wire was fixed.
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mikedevore
Well-Known Member
I would check the basics.
Leakdown & do a cranking compression test.
those two test will give you cylinder & valve condition .
Leakdown & do a cranking compression test.
those two test will give you cylinder & valve condition .
MopaR&D
Nerd Member
Alright, I've been following this thread since the beginning and at this point I don't think the dyno is doing you much good. The operator clearly doesn't know what he's doing as every run it looks like there are issues... the dead #7 plug wire, really? Checking for all 8 cylinders to be firing is super basic, something he should've done before the first run. You shouldn't be the one responsible to make sure he's doing all the proper checks and running things properly. Maybe if he was just a buddy of yours who happened to have an engine dyno and was doing this for cheap but at $800 he should be treating you and your engine the royal treatment.
I think at this point you should put the engine in your car and start another thread in the Small Block Mopar section. Way too many posts in here to wade through that everybody's skipping over and repeating the same **** which is annoying and not helpful to you.
We know the engine isn't internally f***ed at this point it just needs some close attention to tuning. The cranking compression is rather low, once it's off the dyno take the time and do a PROPER cam degree check. Write down your methods and results step-by-step and post them in a new thread.
Things might be disappointing and I understand your feeling unmotivated but hope is not lost, unless you drain the oil and it's full of metal lol... let's hope that's not the case.
I think at this point you should put the engine in your car and start another thread in the Small Block Mopar section. Way too many posts in here to wade through that everybody's skipping over and repeating the same **** which is annoying and not helpful to you.
We know the engine isn't internally f***ed at this point it just needs some close attention to tuning. The cranking compression is rather low, once it's off the dyno take the time and do a PROPER cam degree check. Write down your methods and results step-by-step and post them in a new thread.
Things might be disappointing and I understand your feeling unmotivated but hope is not lost, unless you drain the oil and it's full of metal lol... let's hope that's not the case.
Thanks for the fitting conclusion. I plan on engine install as you said. Wish the dyno operator could read this but I know better. Think he's too proud of a person. I am sitting in carport, as we speak, contemplating the install logistics.
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