hi there, i am looking to buy twin 40's for my 16v engine. i've found a manifold but its off a mk1 1.8 8v i think. will this manifold for my carbs suffice. Any suggestions would be much appreciated cheers scott
weber carbs what did u jet the carbs at and what where your timing settings im having a mare running 40's with 34 chokes 135 mains 180 airs f9 idles 40 pump using a h&h stand alone ignition system with 35 deg advance currently set a start 6 deg at 1000rpm advancing to 40 deg i have no ecu hence the ignition system i was running 145mains,180airs,f8idles,45pump jets and it was rapid but over fueling loads leaving a plume of blue smoke behind
If it's "blue" smoke it's more likely to be oil burning... Try going up on the air's to lean off the mixture further up the rev range.. if the 135 mains have made it feel a little flat, try 140's with 185 airs. What happened when you fitted the 135's ? What fuel jet size are the idle's... 45, 50 ? try some 50 f11's. To be honest yr original settings ar'nt far off.
No, easy enough to set up. If you only want to run the engine standard with an exhaust change and the carbs then 40's will be fine with something like 33mm chokes, if you plan on going for more power later with head and cam work then consider 45's now.
webers the webers ran fine with the other jets just the fact that it was full of flat spots timing i suppose. dont think it will be burning oil as i rebuilt the head only about 1000miles ago and the bores were perfect, the engine has only done 90k. this winter i hope to rebuild and balance the bottom end and lighten the flywheel but thats all just want to brake the 150bhp with the new setup it feels like the 2ltr 16v raddo, no good ill put the 145 mains with 180 airs and keep the smaller f8 idle jets as it seams to tickover much smoother but for now what would you go for as in the whole setup including timing my biggest bugbare timing as there is nothing in writing anywhere for a 18 16v
webers hyad a good luck over my webers today and found that i was missing a mounting stud oops made a new one and just ordered a new set of misab spacers and fasteners, balancing next. also got a brakethrough from the ignition people who i bought it off and they recomend as a base to set the timing at 8-10 deg at 900-1000 deg which should top out at total advance of 45deg at 4500 rpm woohoo
F11's are actually smaller than f8's, the numbers dont run in order, but if it's ok on the f8's after you sort your air leak then go with that, none of the above settings are a million miles off what it should need, it'll just be fine tweeking from there.
I'll start the betting at 5 miles before you melt a piston with 45 degree's advance ! Unless they mean part load, I very much doubt you'll gain power after around 34 degree's under full load (though they've got the rpm about right). As an example, my 8v runs 32 degree's max advance, if I go up 2 degree's I loose about 4hp on the rollers. Not all engines are that sensitive but I've never seen any road or comp engines need more than around 38 degree's max, and that's old engines like a Ford crossflow with poor combustion/squish design. Find out the max advance of the standard engine and maybe run a couple of degree's more than that, but I doubt you'll gain an awfull lot more power even then, most engines with decent combustion wont need much more than low to mid 30's tops. You'll need to get it on a rolling road and adjust the advance from there, run the minimum advance you can at peak that gives you the maximum power.. i.e.. dont run more advance than the engine needs to make peak power.
timing Cool thanks i think i got the numbers wrong the ignition system gives me 35 deg advance and i was recomended to start at 8-10 deg at 900-1000 degrees will ahve to connect a fluc to find out what rpm the top advance is but i would have thought it to be full advance at what 4500rpm on a 16v. This is all new to me just dont want to spend 160 on a rolling road again. its alot of money and i intend to do alot of engine work over xmas like lightening and balancing the block, porting the head, and maybe cams too.
Sounds a bit more like it, though I'd still be inclined to find out what the original advance is at peak for a 16v... anyone ? It'll still need a run on the rollers to find max advance for power... it's not so easy to set ignition up by the seat of yr pants as it is fueling, plug reading and engine response can be used as a good guide to set carbs. Yeah max advance will come in from around 4- 4,500. If yr going for head and cams you'll need 45's over 160hp, which you will "easily" pass.
It wont matter what they're off, hopefully they'll come with 36 or 38mm chokes and close jetting to suit the choke size if they were set correctly on whatever they come off (many arnt !). That would give a good start but again, would need tuning from there to suit the spec.
will keep my eyes out for a set of webers or delotos but will have to sell my set to fund the 45's and as the 40's are only 8 months old from new it will be a crying shame. but if you here of anyone wanting to swap let me know please thanks for all the help again
No probs... Yr unlikely to find anyone wanting to downgrade from 45's to 40's (unless too big for their application), but you should'nt have any probs selling your nearly new ones. Or keep them and dont look for so much extra power !
