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MikeJr. 65 122s project

You can get a bit more aggressive with the DCOE's. SU's get more confused about cams with more reversion, the DCOE's just don't care (as much).

I got an Isky VV81 last time, but I think there are more modern cams out there. The Isky was just cheap and readily available on short notice las time I needed one.
 
I just ordered some F8 65 idle jets to replace my 60s. According to the tuning manual if the idle mixture screw is more the 2-1/2 turns off seat than then you need to change to the next largest size which would be the 65s. I am currently 5-1/4 turns out.

I read on another forum were a guy was having the same hesitation off idle. He found that changing the idle jets to a larger size corrected the problem, even though he was told idle jets only effect idle.

Here is his post:
DCOE Weber "hesitation" tip!
After having the 40DCOEs for about a year - and always accepting a slight hesitation off idle
constantly told: "they're racing carbs kid - what do you expect"
.... I have finally C U R E D the lean spot / stumbling problems. No more slipping the clutch and blipping the throttle to keep the engine happy (although I'll miss the well timed "blipping" at traffic lights :-) !
I felt the motor was hitting a "lean" spot in the fuel delivery / rpm curve - and after being told by many that idle jets DON't affect anything but idle, resigned myself to chasing timing, float level,etc...and just living with it -
Decided yesterday that I'd try fat idle jets anyway.
Here's what I did:
removed 50F8 idle jets - installed what are probably "overkill" 65F8 jets just for kicks. I readjusted idle mix a bit - and the car is as smooth as Motronics!!!! As smooth as a tii? YESSSSS!
So there you have it - Idle jets Can and DO affect progression circuitry in the DCOEs!!! I'll probably go back to a leaner 60F8 or somesuch - but that's where my problem lied the whole time!
Now I can drive "eggshell" if I want to, without motor bucking or complaining. Paul

​

I'm hoping this is the case, but even if it doesn't effect the hesitation the current ones are still to lean according to the tuning manual.



​
 
Yeah, there are only two sets of jets. The idle mixture itself is adjusted by those little needle valves, but once you crack the throttle open the 'idle' jets are feeding fuel in via those progression holes. That's not adjustable, that takes jet swaps.

It's only when the throttle is opened up further that the main jet starts feeding fuel in. With the throttle mostly closed, it's the partial vacuum pulling the fuel in via the progression holes (and that's why they are spread out along the roof of the carb throat - as the throttle opens up it exposes more of the holes to the vacuum).

At some point the vacuum created by a partly closed throttle fades, and the carb choke starts moving enough air to create a vacuum, and that's where the main jets put fuel in - this is based on the volume of air going in (and the size of the venturi/choke).

Obviously, there's plenty of overlap in all three circuits - the idle-actual idle, the idle-part throttle, and the main-open throttle.
 
How many turns past contact are the idle screws? Any more than 1/8 turn and you're off the idle circuit and into progression. If it won't idle there, adjust the bypass screws.
 
hiperfauto said:
How many turns past contact are the idle screws? Any more than 1/8 turn and you're off the idle circuit and into progression. If it won't idle there, adjust the bypass screws.
Click to expand...

The idle speed screw is only about 1/8, but I'm out 5 1/4 turns past contact on the idle mixture screw. That's where it would finally run and idle. The Redline instructions that came with the carbs say to keep the air bypass screws closed while setting the idle, and I've just left them closed. :e-shrug:

Remember I'm still in DCOE Pre-k. The redline instructions seem vague. I downloaded the big weber manual, but it's like reading a Chinese phone book.
 
So I sold my wheels to stick70 aka Kyle, and bought some factory widened steelies with dog dish hub caps. I've always loved the way these wheels and hubcaps look on 122s.

I ordered them from VP Autoparts in SC. They are a great company by the way. Most of the stuff I buy for my car comes from them. They have everything

166239756.jpg

166239757.jpg



I also order some new Goodyear RS-A 195/60R15 tires for them.
 
Nice choice of wheels, I forget that Mattias carries those.

Did you get your carbs dialed in ? What are you running for a distributor ?
 
matt b said:
Nice choice of wheels, I forget that Mattias carries those.

Did you get your carbs dialed in ? What are you running for a distributor ?
Click to expand...

I got the idle jets today and threw them in when I got home from work. I went for a quick drive and tip in has gotten about 90% better. There is a very slight stumble now so I'm on the right track. I may return these and go with a f9 50s, but I want to see what size the Venturi and main jet are so I can do some calculating. Need to retune idle now though and see where I'm at.

It has a stock distributor and pertronix breakerless ignition
 
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I got the F9 50 idle jets and installed them. It improved the tip in even more. I'd say its about 99% better over the original set up. The idle mixture screws are at their max recommended 2 1/2 turns out from full seat which make me think I could go even bigger on the F9s. Maybe 55s or 60s. There is still a very slight stutter under very light throttle, but I would never drive it like this. During my normal driving there is no stutter at all. I'm going to leave the jets where they are for now until I get the B20 in.

I have to say that for me anyway the DCOE are much easier to tune, than the SUs. Now I know that the SUs were 50+ years old, and they surely needed a rebuild, but I could never get them dialed in. The SUs at WOT would spit and sputter, and they never idled very good. The DCOEs are far easier to tune, and the car drives great with them.
 
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Car looks great on those wheels. I have the same ones from VP sitting in my backyard, and seeing your car makes me want to put them back on my 140.
 
SU tuning was also not very static. You'd get them tuned up just right, and 6 month later you'd need to do it again. Just a fairly constant ongoing task. Sort of seasonal in nature?

The DCOE's, however, are almost completely set it and forget it. Side benefit of having most of the tuning comprised of non-adjustable parts. They can't drift out of adjustment.
 
JohnMc said:
SU tuning was also not very static. You'd get them tuned up just right, and 6 month later you'd need to do it again. Just a fairly constant ongoing task. Sort of seasonal in nature?

The DCOE's, however, are almost completely set it and forget it. Side benefit of having most of the tuning comprised of non-adjustable parts. They can't drift out of adjustment.
Click to expand...

Yeah I like the Webers a lot better.
 
MikeJr. said:
Yeah, They look good on 140s too. They look so much wider than they actually are.
Click to expand...

Did you get the tires from Mattias as well ? I like the choice of tire size too, has a nice meaty look without being over the top.

What more do you need to do to this thing ? Looks like you have most of the kinks worked out.
 
matt b said:
Did you get the tires from Mattias as well ? I like the choice of tire size too, has a nice meaty look without being over the top.

What more do you need to do to this thing ? Looks like you have most of the kinks worked out.
Click to expand...

No I got the tires locally. They are little fatter than I thought they'd be, but they ride really nice. I noticed better braking, handling, and the steering feels easier at parking lot speeds. I've never had Goodyear tires on anything, but so far I'm pretty impressed.


I have a few more things I'd like to do to it. I still have a brake issue coming from the rear where I have to pump the brakes up to get full pedal. Also because its lowered I'm having a drive line vibration because the pinion angle is off. I don't really see a way to make any adjustable arms with the early rear end set up.

I'm seriously considering installing an 8.8 4:10L. That should fix the brake issue and I could make adjustable arms to fix the pinion issue, and I've done it before. The biggest hurdle this time will be adapting the weird stamp steel torque rods in the rear, but I think I've figured out a solution to that.

Here is my mental pros and cons on installing an 8.8:
Pros
1. Stronger rear end that I can beat on without worrying about breaking
2. Service parts are more available
3. Price-It's cheap $135.75 at Pull-A-Part and there are a ton of them down there
4. Comes with a locker. Stock rear end lockers/limited slips are hard to find and expensive
5. Same wheel bolt pattern as stock
6. Disc brakes
7. It's wider and will space the wheels out in the rear, which I think it needs.
8. Adjustability with custom built arms

Cons
1. It's hard to do. Probably a months worth of weekends.
2. Weight- It's heavy, I'd say double the weight of a stock rear end. *Weight really isn't much of an issue for me. I'm building a street car, not a race car
3. Drive shaft mounting-Not too big of an issue, but it is something that would need to be sorted out.

I'm pretty much set on doing this. Maybe the first of the year
 
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Tfrasca said:
Wouldn't a 1030 be enough for a warmed up pushrod motor?
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It would, but the bolt pattern would change to 5x108. I'd have to get different wheels or run adaptors. Plus I'd have to track down a G80 or buy some other locker separately. I could source some late model 1800 front hubs and brakes with 5x108 bolt pattern, but that would be an additional cost and work compared to the 8.8. It would be the same amount of work to make it fit.
 
I know at least one guy that redrilled his 1030 to 5x112 on his amazon. One hole had to be welded first and that was the hardest to redrill but it's doable if you have access to the right tools. The holes in the disks he just widened oval, discs are centered by the center.
 
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