My idle speed stays at about 1200 RPM after warmup on my Kadron equiped 2332cc engine. on other VW/Porsche 4's I've always set the idle speed of 850 to 900 RPM. Is there some disadvantage to a higher idle speed? This is the way it came from the builder. Please advise. Thank you
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In my experience getting the idle speed of an engine adjusted to it's lowest RPM that it will stay running is a factor of many things such as the cam specs, the timing and most of all getting the carbs adjusted correctly and jetted correctly. What are your cam specs and what size kadron's are you running? What compression ratio is your engine? What type of heads and what are the valve sizes. Having the idle adjusted high alone doesn't hurt a thing besides sounding funny but it can be a sign of a problem such as a vacuum leak or the carbs not jetted correct for your engine. If the idle jets are the correct size the idle should be able to be adjusted to 800 rpm unless you have a super high duration high lift cam but even then I have seen well set up engines idle under 1000 RPM and sound great. I would also want to know if the engine's Air fuel ratio is correct or too lean or too rich. So, your question isn't easy to answer. Have you asked your engine builder about this? Have you tried to adjust the idle screw? What type of throttle linkage do you have? You would think this would be easier to answer. I am stopping here before I drive myself crazy LOL.. Good luck and let us know what happens.
Jimmy.
Thanks, Yikes lots of info. big like.
While you're contemplating that info, check these simple elements;
CLICK ON PIC TO ENLARGE
1. With the engine warmed up and at idle, check to see if the idle adjustment screws (red arrows) are against the stops on the carb. If not, try to push them against the stops.
2. If adjustment screws cannot be pushed to full rest position against the stops, check the tension of the throttle cable in the linkage (yellow arrow). If you are unable to pull on the throttle linkage to get the adjustment screws to rest on the stops, loosen the barrel clamp holding the throttle cable to allow the adjustment screws to come in contact with the stops. When you have accomplished that, retighten the throttle cable barrel clamp. Check tension of return spring attached to throttle linkage (blue arrow) to be sure it is bringing the linkage and adjustment screws back to full rest position (on the stops).
3. Rev engine and release to see if idle speed has come below the 1200 RPM you've mentioned.
4. If idle speed still seems to high, back off both adjustment screws (turn counter-clockwise) a 1/4 turn. Continue this process until you reach the RPM you desire and the engine continues to run smoothly.
While this pic may NOT be exactly like your throttle linkage set-up, I think you will get the concept of these adjustments.
Hope you find this info helpful! 
The car came with the idle at 1200. I have 800miles on it and in the past on 356's and VW's am used to much lower idle. Lower idle just feels right to me nothing more. Cheers, and thanks.
@MusbJim posted:While you're contemplating that info, check these simple elements;
CLICK ON PIC TO ENLARGE
1. With the engine warmed up and at idle, check to see if the idle adjustment screws (red arrows) are against the stops on the carb. If not, try to push them against the stops.
2. If adjustment screws cannot be pushed to full rest position against the stops, check the tension of the throttle cable in the linkage (yellow arrow). If you are unable to pull on the throttle linkage to get the adjustment screws to rest on the stops, loosen the barrel clamp holding the throttle cable to allow the adjustment screws to come in contact with the stops. When you have accomplished that, retighten the throttle cable barrel clamp. Check tension of return spring attached to throttle linkage (blue arrow) to be sure it is bringing the linkage and adjustment screws back to full rest position (on the stops).
3. Rev engine and release to see if idle speed has come below the 1200 RPM you've mentioned.
4. If idle speed still seems to high, back off both adjustment screws (turn counter-clockwise) a 1/4 turn. Continue this process until you reach the RPM you desire and the engine continues to run smoothly.
While this pic may NOT be exactly like your throttle linkage set-up, I think you will get the concept of these adjustments.
Hope you find this info helpful!
I'll add that you really need a snail gauge to balance the linkage so both carbs operate in unison.
Richard, my old stock '57 VW with a pair of stock Solex carbs (similar to your Kadrons) would idle down to around 300 rpm and sit there, chugging away forever. It would come up off idle OK, but preferred it if the idle was just a bit higher, like 500 or so.
My current engine, a 2,110 with a pair of 40mm Dellorto carbs and an aggressive cam seems to like about 800 rpm as an idle.
Your current 1,200 rpm sounds a tad high, but to reduce it to, say, 800 and keep the carbs balanced side-to-side you'll need a carb sync tool like this:
https://www.cbperformance.com/product-p/6537.htm
If you have that you can turn both carbs down a 1/8 - 1/4 turn at a time until you get to 800 or so and then balance the flow left and right to make it run smoothly.
Thanks Gordon, got one of those sync tools and adaptor for my carbs I’ll have to get into it.
Tips for you:
1. DON'T adjust anything when the engine is cold. Get it GOOD and warmed up.
2. Once it's warm and you change the idle speed, you'll have to re-adjust the idle mixture screws. You may have to go back and forth a few times between speed and mixture.
3. Don't mess with the idle speed screws(once you've used the snail and synchronized).
4. Don't set the speed too low warm, it makes it idle REALLY slow cold and may stall. My car likes 800 warm but I set it to 900 so it still idles cold(after 30 seconds or so).
5. After you get it 100% nailed on the idle stops, have a friend or relative hold it around 1500-2000 rpm while WARM and parked. Then check the carb throats with the synch tool and equalize the air WITH THE LINKAGE. This makes for a much smoother running car.
Cheers.
When making the adjustments should I block the balance tube that runs between the manifolds?
I would, Roy.
Wait!
Was that @MusbJim with a tech post?!?
Surely, this is one of the horsemen of the apocalypse. My world is upside down.
In order for order to be restored, I'm gonna' need more pictures of Jim's car, perfectly detailed, slipping down the PCH, throwing good vibes and looking fine doing it.
Don't let Jim fool you. For all his cruizin' and chillaxin' aww shucks "Random Task" vibe, he's actually quite the tech guru.
Great examples of this are his many azz-kickin' videos, edited to perfection.
@R Thorpe posted:The car came with the idle at 1200. I have 800miles on it and in the past on 356's and VW's am used to much lower idle. Lower idle just feels right to me nothing more. Cheers, and thanks.
After about 1000 miles, I leaned out the idle mixture and lowered the idle speed.
mpg went up significantly and car ran much better.
Interesting. Thank you.
Fine, I'll say it: Kads on a 2332?
You know, I missed that Ed. Good eye. I agree that can't be the best running setup.
And I called you Roy up there. Sorry Richard.
It’s the upgrade from 1914 cc from Vintage Motorcars in Hawaiian Gardens, California.
"Was that @MusbJim with a tech post?!?" - @Stan Galat
"Don't let Jim fool you. For all his cruizin' and chillaxin' aww shucks "Random Task" vibe,..." - @DannyP
Bwaaa Haaaaa! I'm sure you guys noticed that I didn't get into the other minutiae beyond "...loosen the throttle cable.." "...check the return spring..." "...back off the adjustment screws until you get the RPM you desire...". 
Those other technical details just F with my "Keep it simple" mojo, LOL! 
I have one of the first (2019) 2332cc engines with Kadrons from Greg at VS/Hawaiian Gardens. Greg recommends idle speed of 1000RPM. Works for me
Greg set the idle speed at 1200, this I thought was a little high that’s why I asked.
Best to check with Greg. If you like, I can ask him next week when I see him for installation of a Vintage Speed shifter.
Thank you, I talk to him often.
.
I've got a mild cammed 2-liter with Weber IDF's that will idle smoothly at 800 rpm when warm but I've set the warm idle up to around 1100 so I don't have to feed it any gas to get it to idle when it's cold.
Remember, unlike practically every other car on the road today (or even most cars in the '50s) these cars have no chokes* at all. Even in mild weather, they run very differently before the carbs warm up, and when it's really cold out you have to fiddle with them for the first minute or two to keep them running.
(*OK, modern cars don't technically have 'chokes', but the computer adjusts timing, mixture, and throttle settings to compensate.)
With the warm idle set to 1100, two pumps of the pedal, and it starts right up and keeps going in the coldest weather. It's rough for the first 30-45 seconds, but it keeps running.
We all talk about oil and cylinder head temps as gauges of when an engine is 'up to temp', but what makes more of a difference in how smoothly it actually runs is the temperature of the carburetor bodies. There are some very narrow passages that control air and fuel flow and they change significantly in size as they warm up. It takes quite a while for heat to work its way from the heads up through the manifolds and to the carb bodies themselves. (The heavy metal linkages will change in length, too). On a cold day, my engine can take twenty minutes or so until it really reaches equilibrium.
If you're doing final tuning on carbs, you should really drive the car (and not just let it idle in the driveway) for some time before making any adjustments.
.
@Sacto Mitch posted:.
We all talk about oil and cylinder head temps as gauges of when an engine is 'up to temp', but what makes more of a difference in how smoothly it actually runs is the temperature of the carburetor bodies. There are some very narrow passages that control air and fuel flow and they change significantly in size as they warm up. It takes quite a while for heat to work its way from the heads up through the manifolds and to the carb bodies themselves. (The heavy metal linkages will change in length, too). On a cold day, my engine can take twenty minutes or so until it really reaches equilibrium.
The yellow highlight is the only part of this paragraph I agree with. It's the temperature of the heads, combustion chamber, cylinders, and pistons. And yes, of the oil in the engine. Maybe even the temperature of the intakes. But my carbs stay pretty cool, especially when I'm really romping on it. And the passages and jets inside do not "change significantly".
Everything else in your post is spot-on, Mitch. Especially that last sentence. Don't be tuning and fiddling on your car after 5 minutes of idling in the driveway. Go DRIVE it for a while, a half-hour ought to do.
If all parts are sized right even an engine that goes to over 7,000 rpm with power will idle at 8-900 rpm. The 1750 (90 mm piston/cylinders- 90.5's weren't available up here in Canada yet- it was 1980?) in my Cal Look bug went to 6500 with power and idled so much like a stocker that someone once commented on hearing it idle that the car looked like it deserved a "fast" engine. When I told him it was cammed with an Engle W125, a legitimate 14 second car (I had 14.6 second time slips from Seattle Int'l Raceway) and opened the engine lid he was surprised to see 44IDF's and it purring so nicely. I've seen engines with a W130 sound the same- it's all in properly matching parts for engine size and rpm.
I suspect a 2332 with kadrons that won't idle below 1200 rpm needs some 44IDF's or 45 mm Dellortos- even with the larger throttle body sections, kads never seem to run completely right on really big (and a 2332 is 'really big') engines. There are lots of horror stories on this great big interweb about guys not being able to get these modified carbs running properly on larger street engines no matter what was done, our own Stan being one such unlucky soul (I believe he still has them in a box in his garage and will sell them to you fairly cheap if you're interested).
PS- And yeah, what Danny and Mitch said- trying to adjust carb stuff before the engine is fully warmed up is just asking for trouble...
@ALB posted:I suspect a 2332 with kadrons that won't idle below 1200 rpm needs some 44IDF's or 45 mm Dellortos- even with the larger throttle body sections, kads never seem to run completely right on really big (and a 2332 is 'really big') engines. There are lots of horror stories on this great big interweb about guys not being able to get these modified carbs running properly on larger street engines no matter what was done, our own Stan being one such unlucky soul (I believe he still has them in a box in his garage and will sell them to you fairly cheap if you're interested).
PS- And yeah, what Danny and Mitch said- trying to adjust carb stuff before the engine is fully warmed up is just asking for trouble...
To be clear, what I've got is a set of AJ Sims' heavily modified Kadrons with 46 mm throttle plates. They're vintage 2005, and the problem was the needles and seats (which could not be made to work for love or money), so the entire arrangement flooded at idle. I'd sell them to anybody who knew they were going to be a problem.
I did this before I knew anything. I was ready to send them to Art Thraen, who gently helped me to see the error of my ways (trying to make a silk purse out of a sow's ear) and sold me a set of 40 DRLAs, which ran perfectly right out of the box.
Kads can be made to work on a big engine (in the same way that a fat man can be made to run a mile) but they don't do a very good job and there are a lot of easier ways do it better.
A 2332 would love a set of 44 IDFs or some 45 DRLAs.
Thank you for all your replies. To be clear I was asking about the idle speed and I have no idea yet that I cannot change it to a lower speed. Greg at Vintage only offers Kadrons on his engines and when I asked about Webbers he said he didn't like them. I don't know what mods he or his engine builder does to the Kadrons but apparently something is done. To date I have no problems with this setup, it goes like stink, and I am happy with the response. I will lower the idle soon. Thank you for all the advice. Cheers.
Richard
After talking to the "Kadron" guys at Kaddie Shack they say that 1200 RPM is not a bad idle speed for these big carbs. Interesting.
I agree with Richard. Greg has Kadrons dialed in for his engines. I wouldn't do anything more than a very slight adjustment to the idle screws.
Carbs can be a slippery slope when you don't know what you're doing, like me, and start turning airflow screws and linkage adjustments.
I'm curious, what size venturis did Greg put in that motor?
Greg advertises 145hp from his 2332 with Kadrons. I don’t know what heads, cam, ect his builder uses in these motors, but they are leaving a lot of power in the stable on a motor of that size. A pair of Panchitos, a K8 cam and 44 IDF’s and that motor would make 175hp.
@LI-Rick posted:Greg advertises 145hp from his 2332 with Kadrons. I don’t know what heads, cam, ect his builder uses in these motors, but they are leaving a lot of power in the stable on a motor of that size. A pair of Panchitos, a K8 cam and 44 IDF’s and that motor would make 175hp.
Unless I'm mistaken, he's already got the Panchitos.
I think I know why Greg does what he does (plugged idle jets leap to mind), and it makes sense from a business standpoint. I would imagine he doesn't deal with very many dissatisfied customers doing battle with their carbs. I fought a set of 40 IDAs on my first car, never had a moment's issue with the ICTs on my second, and vowed to never deal with individual runner carbs again when I was doing a 2110 for my IM back in 2005. It's how I ended up with the world's most expensive set of Kardons, which never did work correctly.
I now have a pair of every DRLA Dellorto ever made (except for 36s) including 48 tri-jets, and at least 4 of every idle and main-jet I could possibly need.
It turns out, it's worth the learning curve (at least to me, anyhow).
Regardless, I grew up setting the idle as low as it would go and still stay running. With my car, I've slowly crept the idle up to about 1000- 1100 RPM (hot) so the engine will be able to idle when cold. It's also a lot easier to tune out the off-idle flat-spt with an idle above 1000 RPM.
Danny's set-up had the best of all worlds (great idle, zero flat-spot), but Danny is a carb-whisperer and has crank-fired ignition
... and as we all know, 95% of all carburation problems are ignition.
I believe my engine has Panchito heads but I don’t know what cam. What I do know that it has torque up the you know what and access to the Kadron jets is simple. Cheers.
One thing about my idle after about 5 min it stays at 1200 RPM.
According to Greg's engine engine description handout, the 1914 and the 2332 engines have "new dual port heads with 40 X 35.35 valves and single high rev springs CB Panchito".
He also lists "VM2 cam for Solex carbs CB Performance".
I agree about the plentiful torque. 2nd gear can be used from a stand still.
145 reliable HP is plenty for me. Every mile is a smile!
And you can get to a clogged idle jet without removing the air cleaner. Happened to me after my Sunday drive.
@Stan Galat posted:... and as we all know, 95% of all carburation problems are ignition.
My 1776 with dual 40 mm Dells had a horrible off-idle flat spot when I bought the car. Turns out the Magnaspark distributor's centrifugal-only advance was the biggest piece of the puzzle. Replacing it with a Pertronix SVDA distributor made a huge difference. The rest was in the messed up ported big valve heads that came with it. Replacing them with new Empi 40/35.5 mm and matching manifolds made the rest of the difference. The engine pulls strong from 2000 through 6000 RPM, and never stumbles off the line once it's warm.
When I was in for my first service, Greg removed the Kadron carbs and did some type of minor modification to them. You can get details next time you talk to him.
Thank you, Greg said the carbs had been modified when I picked the car up in November. Who knows.
@R Thorpe and @jprpdr- you guys both have 2332's with kadrons, right? How high do your engines rev (with power- they will rev 500 or more rpm higher but you'll have felt the engine 'peak') in 3rd gear?
PS- In first and second it's much harder to feel when the engine 'peaks' and power starts to fall off, even though the engine is revving higher and the car is still accelerating- that's why I ask about it specifically in 3rd.
Thanks guys! Al
