If you have done all of that work on a car by yourself, recurving a distributor will be like a walk in the park. Just read Larry's thread. Peace, Kacper.
I just reread this thread. How do you know the distributor needs a recurve? All we know is that you set the initial timing to 12*. In order for you to evaluate this distributor, you need to know what the timing is at higher RPM, and when all the mechanical advance is in. Using a timing light, you can verify that the mechanical advance, and vacuum advance is working. You can also measure the total advance. Initial timing means very little as advance changes as soon as you go above idle.
Larry, I got him on the "recurve" thought process. Nailheads are basically 61-63 and the 2x4 distributors are 12* initial and curved for the best power. If one is using a 2.5* or other initial distributor, the curve is different and that will result in poor timing/advance events if one of these distributors is set at 12* initially. And over the years, with all the swaps and number of hands on the engines, one needs to verify the distributor they are using, and still cannot be 100% that internal parts were not swapped. My intent was to point out the distributor needs to be "known" since it can impact so much, not to muddy the water or confuse things.
I'll get on to checking this when I can find the time and post results. Right now I've got back issues , so not a lot of mobility to bend , crawl under cars etc. It will give me a chance to find a dial back timing light. Thanks
Modern engines with multiport fuel injection run at those RPM without issue...will a throttle body FI work?
Personally I wouldn’t want to drive around under 2000 RPM it will simply cause detonation and it won’t help fuel mileage. Put the shifter in drive and only use overdrive over 60 mph.
Go do Yoga, best thing for back pain, 13 years ago I got a sentence and they told me that I have only 2 months and if I don't go to make back surgery I will land on a wheel chair. This was the last time they saw me. 13 years later and I am still snowboarding, riding my Enduro bike and I am still working as a mechanic and I am almost 50 but I get up every day at 6am and doing at least 30 minutes of yoga. What is most important I still can install q-jet intake by myself without any help . Much health and much wealth to you, Peace, Kacper.
Here’s a simple technique that I have used to troubleshoot a low speed drivability problem that may be related to the carb. 1) get the motor up to normal temp , as in 10 minutes of driving. 2) adjust the idle mixture screws richer so that the idle rpm drops by about 50 to 75 rpm. 3) take the vehicle on a drive again and see if the off idle light throttle low speed flat spot is still as bad. If it’s better then you know that the low speed mixture is too lean . there are a few ways to richen this up on a Q jet.
After reading the timing light directions quite a few times I set it up and tried it. Tested for mechanical advance and registered only 6 degrees at 2200 RPM ? Not sure yet what's going on, will give another try another day. On a more positive note ---- found a major reason for engine stumbling. One spark plug lead shorting out badly effectively running on 7 cylinders. Running much better now but still need to address axle ratio. Purrs nicely at 60mph in OD but lacks power to accelerate further. Who runs spark plug covers on their Nailhead ? Can you post a picture on how / where you routed the plug wires under the covers please.
Did you check at a higher rpm too? The stock mechanical advance springs don't allow full advance until approx 3900 rpm. I don't know exactly which model distributor you have, but here are the 1966 specs:
No I didn't try any higher. I was trying to hold the timing light, press buttons and pull the throttle cable all at once. The distributor came with the 1959 401 engine. Distributor numbers 9 A 30 1110956
