360 does not seem to be making power and is slow in the 1/8. Need help and/or suggestions

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Oldmanmopar said:
I reference his combo. His stall is to low for that motor with that cam and compression. 4500 would work a lot better. If the car don't 60 foot a higher stall converter will be the way to go. This is just experience I have had.

The video above the car went 10.79 and weighed 3850 with driver. stereo playing, spare in the trunk through the mufflers, LOL Barely got it wound up in drive, 5500 stall . What gears do you think?
Click to expand...

what i was talking about assumed one had the right convertor.
Just where you can hold it on the footbrake doesn't mean anything regards effecting ET
 
where it foot brakes without resistance means a lot on how you can hold the car. In the video above even though the car has a 5500 converter you can see the car picking up against the brakes at 3000. The lower the RPMs on the brake would raise the flash due to inertia of RPM climb. Lower RPM's on the brake would raise our flash stall on the launch 100-200.
 
@PRH gave you best advice so far. Find a local tuner and get it to the chassis dyno for a session. Get some accurate data on the car to find out if the engine is happy and if not let them tune it on the rollers and make it as good as it can be before you throw any other money or parts at it.
 
Get an 8 inch converter and you'll be happy!

You would not believe how many customers I told this to and they came back Happy!! some 3500 but yours needs a 4500 for a low compression SB with that cam
 
I’ll never understand how issues like a combo that underperforms, where it’s clear the jetting and possibly the timing is off, the tuning skills or better yet “attention to tuning” have not been addressed, yet we immediately get recommendations of changing everything: cylinder heads, torque converters etc etc. My advice is to install an AFR gauge (learn to read plugs later.....fast track carb tuning with the gauge! ) attack that carb circuit by circuit, play with timing. Maximize, learn to tune what you have, then move on to how it launches and runs out etc where then you can replace what may need upgrading
 
Total timed it... with a curve? UGH. It may not be clean off the bottom and is lacking initial timing. Clean that up and the convcerter may stall higher because it's making more power down low.

That cam, it should have at least 18* initial on it and up to about 24. I hate total timing stuff because of the curve. If a distributor has 28* mechanical in it and another has 10*, they will run completely different down low. The 28* one will be a fricken DOG... I'd start with a clean baseline idle tune and start from there.

Get the jetting back to stock and run it.

@12many yep, it runs bad and it's the converter. A fricken stock converter in that car should run 1.75-1.80 60' The tune is MILES off...
 
The AFR gauge would be a great help. Good to get you in the ballpark. Also what the gauge does when it stutters greatly reduces the number of possible causes. It stutters and the gauge goes lean, fuel supply. It stutters and goes rich, ignition. This is overly simplified, but works for most issues.
 
Ok guys thank you for all of your help so far! Sorry it took so long to respond, things have been crazy on my end!
So here is an update, we found something goofy with the distributor that seemed to be making the car flat. The last person that had the distributor before us must have been screwing with it and the plate that held the pickup coil was actually loose and had the pickup coil in all different spots, sometimes really close to the sprocket and sometimes not touching it at all. Just for kicks; we had a stock distributor that we had a stock distributor around with one large spring and one thin spring. We took the large spring out and left the thin spring in just to see what would happen. The 60 foot didnt change too much but the car picked up almost 2.5 tenths. the car went 8.80 at right around 80mph. All that was changed was the distributor. Since the 60 foot still stayed the same im assuming it will be a converter change over the winter to make that improve. It was around 2.05 again, so I have to guess that based off my research that it will need to be mid 1.50s-1.60 60' to get mid 7s. Just wanted to give an update; hope this helps in any way
 
Also, as for anyone who asked about jets in the carb, the best i can tell what came with this carb was 74 primary jet and 84 secondary. Should we do something different, or is there any better jetting reccomendations??
 
The recommendation has already been made to find out what jets the carb came with and put those back in. Learn to read a spark plug and use your trap speed to tune it thereafter. Also see what powervalve is in the primary metering block. Divide your cruise vacuum in half and the power valve should be close to that. This is a good starting point.
 
If the motor is no longer skipping and popping, and will cleanly pull to whatever rpm you feel comfortable with....... then it’s time for a flash stall test, to see exactly how the current converter is behaving.

Also, how is the timing being set?
 
If you have the ways and means that combo is screaming 904 with low gear and properly spec’ed converter :)
 
I read through this thread again, and didn’t see if it was mentioned as to whether or not part of the pathetic 60’ times were the result of tire spin.
If it’s not really spinning the tires....... after looking at the overall combo...... I don’t know how you could possibly end up with 60’ times that bad, out or that pile of parts.
On paper, the combo looks sound.

Since the OP has gotten the skipping to stop, yet the 60’ times are still terrible..... the two things don’t appear to be related.

So...... the question for me is......spinning off the line?
Or not?
 
crackedback said:
@12many yep, it runs bad and it's the converter. A fricken stock converter in that car should run 1.75-1.80 60' The tune is MILES off...
Click to expand...

440BelII said:
Ok guys thank you for all of your help so far! Sorry it took so long to respond, things have been crazy on my end!
So here is an update, we found something goofy with the distributor that seemed to be making the car flat. The last person that had the distributor before us must have been screwing with it and the plate that held the pickup coil was actually loose and had the pickup coil in all different spots, sometimes really close to the sprocket and sometimes not touching it at all. Just for kicks; we had a stock distributor that we had a stock distributor around with one large spring and one thin spring. We took the large spring out and left the thin spring in just to see what would happen. The 60 foot didnt change too much but the car picked up almost 2.5 tenths. the car went 8.80 at right around 80mph. All that was changed was the distributor. Since the 60 foot still stayed the same im assuming it will be a converter change over the winter to make that improve. It was around 2.05 again, so I have to guess that based off my research that it will need to be mid 1.50s-1.60 60' to get mid 7s. Just wanted to give an update; hope this helps in any way
Click to expand...
Why blame the parts? Just for an example, my Duster with 2.94 gears, 100% factory stock converter and with a basically stone stock 360 and stone stock cast heads cut a 1.86 60 ft and ran 8.40's in the 1/8 (I've since swapped heads). I posted this so you can see how far your tune is off. Why do so many just throw money and parts at their build till they get the ET they want. Tune tune tune..... Your combo should blow mine away!! TUNE!!!!!!!! there, I'm exhausted... LOL :D
 
440BelII said:
Should we do something different, or is there any better jetting reccomendations??
Click to expand...
Make a list of the primary and secondary jets, accelerator pump discharge nozzles, pump cam colors, power valve etc and list them here. Some of the better carb guys may come up out of the basement and offer some helpful advice? Ever hook a vacuum gauge up to check idle settings, cruise vacuum etc?? Done some plug readings?? Install that A/F ratio gauge yet??:poke:
 
PRH said:
I read through this thread again, and didn’t see if it was mentioned as to whether or not part of the pathetic 60’ times were the result of tire spin.
If it’s not really spinning the tires....... after looking at the overall combo...... I don’t know how you could possibly end up with 60’ times that bad, out or that pile of parts.
On paper, the combo looks sound.

Since the OP has gotten the skipping to stop, yet the 60’ times are still terrible..... the two things don’t appear to be related.

So...... the question for me is......spinning off the line?
Or not?
Click to expand...
Thats what we thought, we thought the combo looked sound as well. And no the car is not spinning at all off the line
 
12many said:
Make a list of the primary and secondary jets, accelerator pump discharge nozzles, pump cam colors, power valve etc and list them here. Some of the better carb guys may come up out of the basement and offer some helpful advice? Ever hook a vacuum gauge up to check idle settings, cruise vacuum etc?? Done some plug readings?? Install that A/F ratio gauge yet??:poke:
Click to expand...
Have not hooked up vacuum gauge, we looked at the plugs and they dont seem to be bad at all. They arent black like fouled out. And have not gotten the A/F gauge installed yet
 
So do you have a ET slip you can show?
1/8 mile right?
Does your track have a half track reading (330 foot)

Are you removing the vac advance when your checking initial timing. What is it at idle? How much rpm does it take to get full mechanical advance? What mechanical advance springs did you say you had in the distributor? How much advance is in the distributor. In other words if you set the initial at 20 degrees, how many degrees will it advance to??????

With out having any of these answer...........I say you need to twist that distributor base in a more advanced direction.
 
How about an update. Ever get things sorted?
 
I realise this is an old thread, and i havent read all the answers, but... if i put together a combo that should run easy sevens, and goes very low eights, id be disappointed. If it goes nines, i would look for something seriously, and obviously wrong. My first thought was, the limiter chip is bad, or something else seriously wrong with ignition. Fuel wont cause it to be dead at the starting line, unless you have none!
Second, did you degree the cam? A full tooth off will turn a decent motor into a dog.
The few posts i did read, some advised to tune what you have, and diagnose the problems, dont just throw parts at it. I agree. Until you diagnose WHY its so slow, parts wont fix diddly.
 
Last year my buddy was running & having the same issue... Fuel pressure was to high.
Dropped the regulator & set pressure at 5.5
Fixed the problem. However it might just be you're not getting enough fuel with that pump for the mid-top end.
 
Shouldnt be a fuel pump issue if its a dog right out of the gate.
Seen guys go 9’s with 5/16 line.
Seem to me more the convertor is junk.
Even a stock convertor it should 60 foot better if it isnt spinning the tire on the hit, and he said it wasnt
 
Hes got a decent combo of parts wrapped around a engine that should make 425hp or more. It looks like its making 250hp, maybe. Find out why.
Fuel pessure and volume check? Compression check? CAM timing check, not just ignition timing? He has at least a hundred horsepower missing, and the engine is struggling and wont rev. I find it hard to believe that is a drivetrain problem!
 
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Okay , sorry for not updating. Life issues have been keeping us busy on this end.Here's where we're at. We decided to change the converter after talking to a lot of people. So, we pulled the motor because I also wanted to degree the cam. When I pulled the timing cover, I found a chain that had what I would call excessive play for the amont of run time that it has.I ordered a roller chain and gear set with a 9 keyway crank sprocket and used that instead. It's tighter than the one the machine shop installed.While I was playing around with the cam, just for the hell of it, I slid both crank sprockets on with both of them with the dots straight up . On e of the sprockets was a 1/2 tooth off from the other. So my first question is, which one's lying???I ended up using the new timing set that I bought because after degreeing the cam, it seems to be right. The motor is back together, going back in this weekend. We have also decided to run a MSD box as well as go to a Holley Blue electric fuel pump and 3/8" fuel line.Hope to have it ready in a couple weeks for the track test and tune.
 
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