not at idle!! and its not bang bang its pop pop. wanna get this right

oh right yeah thats not cool. haha. something must be wrong there

So I've tried having the pilot screws out 2.5 turns, 2.25 turns, and 2 turns. Whatever I set the timing to at either pilot level it still pops at idle irregularly. Any ideas?

Heres a youtube video of the popping at idle..

mine does this too random popping sometimes and I've had the carb balancer on it. piston one was in the black on my gauges, two was normal, 3 and 4 were late ignition timing so moved the distributor nearly all the way back as it was full advance or retard so its now just over the other way and says 2 is more than normal 3and 4 are just into normal and 1 is late ignition and i think its running rich but the plugs told me 1 and 3 are fine 2 is slightly lean and 4 is rich.

any help much appreciated

did you get it rolling roaded? I'm just trying to get mine running well enough to get me there. Have now got 145 jets to play with.

Am also going to try using a little bit of petrol resistant gasket sealant on the inlet gasket when I replace it (have currently got the mani off to have the other three vacuum outlets welded on)

Will let you know how I get on. I *suspect* my issue is a combination of running lean (small jets) plus no vacuum advance, plus possibly air leak on the manifold. I'm on the right track to fixing these three issues so will report back shortly.

ok thanks and have not had chance to get it rolling roaded yet tbh its only been running a week and have no idea where to take it locally i know of one place over in silverstone but they didnt sound like they were very interested and wanted 200 plus for doing it and that was charging hours labour and per run on the dyno til it was set right where as alot of places give you a price to do it if they know what they are doing like bogg bros really wish it was closer to me

I'm taking mine to pdq in slough. 75 quid an hour and they know their stuff from speaking to them on the phone anyway. Google seems to like them.

i have that poping on mine when on idle

Pete: how far are you from southam? They have a place there that Mark crox took his too. I will be going there also

and me maybe, or aldon automotive!

prankstar thats not too far away will give them a call do you know a rough price they would charge just so i know thanks as a place in northampton i called today said about 3-4 hours on the rolling road at £90 per hour fuck that lol

I'm not sure. Mark crox is the man to ask a I know he uses them

Ello!

Yep the place in Southam is Southam Mini and Metro Centre... Really good guys! Perfectly set up my AFH and I'll be taking my ABD there next week :)

right spoke to them today and said it would take from 1 to 4 hours and they would need the car for 2-3 days to also get parts in if they were needed like new jets etc and they cant fit me in til thursday/friday and this would cause trouble with work and i would rather be there while they are doing it, the price isnt bad though £100 for first hour and only £50 for each hour after so max of about £250 but its 50 miles away and like i said it would cause trouble for me getting to work.

Mark how long roughly did they take to do your afh just want a rough time.

going to ring up rgs motorsport in wellingborough again tomoz as rang them today they are more expensive at £100 an hour but he said around 3 hours and il see if i can take it and get a run on the dyno see whats happening and see if we can tweak it just for now to run better while parts are ordered if they are needed and he seemed quite happy but they also cant fit me in til next week either and wanted to run the strip at gti so probs not going to now just to be on the safe side especially as I'm getting 20 mpg lol major need them setting up lol

So I refitted the manifold with new vacuum advance outlets, and I've used a smear of gasket maker on each side of the inlet gasket as well as torquing it properly to 18 lbft (ha), also fitted 145 jets. Runs a lot better and smoother now. However I need to reinforce my runner hose as it's a bit flexible, so I'm going to cut some small lengths of 38mm stainless exhaust and sleeve it insde as this will be just as good and easier than finding the right suction hose. (I need it to be heat/fuel resistant and resistant to negative pressure, as well as stretching over the carb shoulders which are 42mm OD and the manifold runners which are 38mm OD)

you will see form the pictures when it's at idle the pipes are 'compromised' although when you pic up the revs and the slides open they fill up..

heres the pictures

new manifold finished

tight fit, engine off

running at idle

running at idle

You need less gap between the end of the mani and the carbs, the rubbers should only really be used for joining them together. Try cutting them down abit and sliding them down the mani a bit more bro

Not possible mate.. if I do that I haven't got space for the filter. This will work perfect. And I'll probably be the only one running proper filtering with these carbs.

how does it run with the vac ?

Pipes aren't rigid enough. You'll find that at different engine speeds and loads the cross-sectional area of the pipes will change. This will have a dramatic affect on the speed and pressure of the fuel/air flow and also atomisation. Pressure changes in the inlet tract will upset the ram affect that occurs as the air rushes into the cylinder, changing the mixture etc. You may even have a stalling affect on the air when you stop accelerating.

Vacuum take offs for the VW distributors need to be adjacent to the butterfly. Mid inlet tract means that full advance will be on under W O T which is not what you want.

If the car sounds like its randomly popping and stumbling get a strobe light on the timing pulley and check to see if the mark is dancing about. I've had a knackered hall sender that randomly adjusted the timing at idle and caused my car to run like a bag.

Redroller- as per my above post I'll be 'sleeving' the hose with some 38mm stainless pipe so this problem will be fixed before it's driven.

Why does it need to be adjacent to the butterfly? It'll still generate more vacuum when the engine revs higher anyway, won't it? This is how Cymro and MikeyMK run theirs without any issues?

I've sorted the idle popping issue, it was down to the jets being too small (now got 145s) and possibly an air leak on the inlet manifold (which if it was is now fixed now I've used gasket amker on the manifold as well as the gasket itself)

Maybe I should change the title of the thread but I don't want people to forget the thread if they are still actively helping..?

Mark how long roughly did they take to do your afh just want a rough time.

The car was there a week but in total I think they charged me for 3hrs labour

Not possible mate.. if I do that I haven't got space for the filter. This will work perfect. And I'll probably be the only one running proper filtering with these carbs.

i mean u need to push the crbs further towards the head, what would stop the filter from fitting?

Not possible mate.. if I do that I haven't got space for the filter. This will work perfect. And I'll probably be the only one running proper filtering with these carbs.

i mean u need to push the crbs further towards the head, what would stop the filter from fitting?

I know what you mean dude but if it's closer to the head then the air filter won't fit as it will foul the master cylinder.

Not possible mate.. if I do that I haven't got space for the filter. This will work perfect. And I'll probably be the only one running proper filtering with these carbs.

i mean u need to push the crbs further towards the head, what would stop the filter from fitting?

I know what you mean dude but if it's closer to the head then the air filter won't fit as it will foul the master cylinder.

ahh fair play i see what you mean. isnt there any way of modding it? id rather a modded filter than bodged carb rubbers, shouldnt be too hard?