27 replies to this topic

[CrxTom]

Now, if only we had a way to adapt/supplement all this good info for the SK racing carbs that mine has. They are Weber-like, as far as I know, but that's about the extent of my knowledge. I "ear-tuned" with some decent luck: simply have the car running and warm. Turn each of the two adjustment screws on each carb (one at a time, of course) in, and when the engine starts to choke a little, loosen back up, the goal here is to make the engine run the best you can. I did that all across the carbs, four screws, and it seems to run *OK*.

Learning as I go too...

[OG Wagon]

Now, if only we had a way to adapt/supplement all this good info for the SK racing carbs that mine has. They are Weber-like, as far as I know, but that's about the extent of my knowledge. I "ear-tuned" with some decent luck: simply have the car running and warm. Turn each of the two adjustment screws on each carb (one at a time, of course) in, and when the engine starts to choke a little, loosen back up, the goal here is to make the engine run the best you can. I did that all across the carbs, four screws, and it seems to run *OK*.

Learning as I go too...

Nice bump. Thank you. To aid in completing the above described process:

I have heard that using a +/- 2-foot length garden hose or fuel hose and holding it up the intake port of each carb (with the filter OFF) will serve is an amplifaction device that will let you hear the "pitch" of each runner more precisely. Just hold one end of the hose up to the carb intake port, and the other end up to your ear. Like a doctor with a stethoscope....who is trying to tune a guitar with it! While listening to each port one at a time, use that ports "Pilot" screw to tune each carb to the same "pitch", and once you can verity that each runner has the same pitch, the carbs should then be synced.

Once done, don't mess with your pilot screws anymore. Just use your idle adjustment screw(s) to adjust your idle form that point onward.

ADDITIONAL NOTE: Whatever you do, DON"T OVER TIGHTEN THE PILOT SCREWS! Just lightly screw them down until they meet their seat, then back them out. If you force them back in to their seat, you can damage the seat of the screw, or the screw tip itself will break off, get stuck in there, and then FOREVER block that pilot hole, making them virtual impossible to tune until you can get the little tiny micro-sized broken off tip of metal out of the pilot seat. Which, trust me, is NOT an easy task.

[CrxTom]

One carb, on the driver's side, makes an odd noise like a little chirp (mechanic and I joke about a chipmunk caught in it) that makes noise when it feels like it. At idle, it will chirp along merrily like a cricket, only to be silent a wile, then start again. I'm sure they could use a rebuild...mechanic seems to think you can easily source the kit "It's just a side-draft carb..." but it seems like it would need to be more model/manufacturer specific than that. Any ideas?

Also, the base gasket on each is a rubber-formed orange/red thing, clearly visible pinched between the carb base and the intake. I keep wondering how tight these want to be, as I don't want to kill the gaskets but I don't want to be sucking air either. The bolts are visibly unequal all around the bases; I've adjusted some but am nervous about it.

[OG Wagon]

One carb, on the driver's side, makes an odd noise like a little chirp (mechanic and I joke about a chipmunk caught in it) that makes noise when it feels like it. At idle, it will chirp along merrily like a cricket, only to be silent a wile, then start again. I'm sure they could use a rebuild...mechanic seems to think you can easily source the kit "It's just a side-draft carb..." but it seems like it would need to be more model/manufacturer specific than that. Any ideas?

Also, the base gasket on each is a rubber-formed orange/red thing, clearly visible pinched between the carb base and the intake. I keep wondering how tight these want to be, as I don't want to kill the gaskets but I don't want to be sucking air either. The bolts are visibly unequal all around the bases; I've adjusted some but am nervous about it.

Huh. We'll can't help you with the chirp noises. Never heard that with mine. However, I can give you a little advise about the gaskets at the carb base. I don't think you can over-tighten your carbs to the manifold. I mean, you don't want to strip the bolts, obviously, but you know what I mean. I DID have some vacuum leak issues with this very area of the set-up, so I'm SO glad that you brought the topic up, as I had forgotten to document this in my initial post here. Our engines, as you know shake/vibrate A LOT! So, the carbs take some abuse, and even with a good snug torque on the bolts, the shaking of then engine (and thus, the carbs) will cause the bolts to back out over the course of a few weeks, causing vac leaks at the carb base and intake manifold base (where it mates to the head). The solution for me was to take each bolt out and add some BLUE Loc-tite to the bolt threads. I then torqued each one down as much as I could get them with a hand wrench. This method kept the bolts snug during daily driving for about a month or so of driving. Every month, I made a point to re-check each bolt of the carbs and intake manifold and re-tighten as necessary.

Hope this helps!

[CrxTom]

Good ole Blue. I find he helps me a lot on these engines, for sure. There is definately a lot of dancing about under the hood. I saw in some posts where people had added Window Weld and such to the engine mounts just for the extra strength. I need to replace mine, so when i do, I'll surely try that. Anyway, back to the point: thanks for the tip. I'll snug them all (again) to a consistant level, all the way around. That alone may be the chirping..a little air sneaking in there. Still can't believe how easy it is to work on these engines, generally speaking.

Your posts are (pretty much) always helpful. Appreciated!

[stevo911_]

Cool build thread! I was hoping to do the same sort of set up with some dellorto DHLA 40's (they're basically an improved weber/mikuni) with the Dellorto's/TWM manifold i've got sitting on the desk beside me (got the fuel pump/regulator/K&N's together as well). But plans have changed so I dont think the side-draft CRX will happen for me

[OG Wagon]

Cool build thread! I was hoping to do the same sort of set up with some dellorto DHLA 40's (they're basically an improved weber/mikuni) with the Dellorto's/TWM manifold i've got sitting on the desk beside me (got the fuel pump/regulator/K&N's together as well). But plans have changed so I dont think the side-draft CRX will happen for me

Thanks. Bummer. Sorry to hear that. If it doesn't work out, make sure to list them for sale here on RPR first!

[stevo911_]

I deffinately will (I've got a shed full of 1g stuff I'll probably be selling off)! I just dont have enough time to monkey around with motorcycles, cars, surfing, paintball, snowboarding, work and school, I have to thin out the herd a little bit, and am thinking about getting a truck or SUV to make my other hobbies a little easier (though I do like the little 1gs)

[Maine_Honda_Racer]

I now have Tom's car so this will be of great benefit to me. Thanks.

Here's a good link for tuning Webber or SK racing carbs like mine:

http://www.teglerize...e/webertune.htm

[OG Wagon]

I now have Tom's car so this will be of great benefit to me. Thanks.

Here's a good link for tuning Webber or SK racing carbs like mine:

http://www.teglerize...e/webertune.htm

WOW! That was an intense read. Thanks for including it in the post! What a valuable tool this will be to all the side-draft dudes out there!

[stevo911_]

Thanks. Bummer. Sorry to hear that. If it doesn't work out, make sure to list them for sale here on RPR first!

Done! This is currently the only place I have them listed, so we'll see what happens!

[rsjapan]

very good thread !!!
I found a lot of information I'm really happy !!

Edited by rsjapan, 13 November 2011 - 11:00 AM.

[rsjapan]

ok that's my engine with a side draft weber 45 DCOE
(not adjusted basic tuning)

air jet : 195
fuel jet : 145
emulsion tube : F16
fuel pressure 2.0