Should this gasket be trimmed to suit the ID of the two mating faces? I’m going to attempt to set up the air fuel ratio, is there a max/min figure I should aim for with a stock T4 2.0? Thanks for reading this.
It has to be fitted and driving to afr tune is why I asked. Best not to look at the gauge for best idle.
When I AFR tuned my Dells the numbers are continually changing .. I settled for mid 14’s :1 at around 55mph . Kept upping the main jets till I achieved it . Idle was high 13’s:1 . Every other speed , accelerating etc gave wildly different numbers . Ideally manifolds ,carbs , filter bases should all be matched
With AFR unless you’re rolling road setting for max bhp you are really making sure your not running dangerously weak. Good to be in the 14’s while cruising but don’t worry too much about AFR at idle, mine 2.0 type 4 twin Weber ICT’s idles nicely at 13:1 any weaker and it starts to stutter a bit.
My Idle ends up at 12.8-13. WOT 12.8-13.1 Idle jets as low as you can IF YOU HAVE SVDA and want to tune for mpg.
To get an idea of throttle the idles cover, take the main stacks right out and go for a drive. I'd be interested in how fast you can go in a car like that. 30-35mph in a bus, but maybe 50mph or more in a car making the small idles more effective.
Thank you all for the replies. Maybe I need to supply more info. This is a spare rebuilt stock engine on a bench ATM. The distributor is a o/hauled 009 see photo. One of the reasons I'm setting the carbs correctly up on this engine is to be able to run in a new cam on another engine soon to be built, I think this is the right direction? The other engine will be running a 205P with vacuum control see photo. In hindsight I should have used the 205P on both engines. Will this make much difference in the short term setting up the carbs to run in a new cam? thanks for you patience.
No, fine either distributor, but leave the afr in it's box it'll be useless to you. You'll be running the cam in on the idles, it'll not be under load so you won't damage anything whatever you do but might pop and fart with too little fuel. I'd go for 57 - it'll start easy and also in the name of getting it going initially make sure your pumps are pumping. It'll get quite hot but that'll be the new rings not afr. I give em a rest for 20mins half way through...some people don't even bother running the cams in at all uneless it's a really wild one but better safe than sorry. 2,000rpm as you know is quite slow, I wonder when peeps report of the racket/neighbours if they guessed and ran it in at 3-4,000rpm. lol
Don't think you need it 'tuned' for the break in, running ok should be good enough for 20 minutes as long are jets are close and advance pegged back at 28-30 I'd have though you'd be good to go? Sent from my SM-G930F using Tapatalk
It’s impossible to set the carbs correctly on an engine stand – there’s no load. And timing isn’t particularly important; as long as it is in the ball park you won’t be running the engine fast enough to reach maximum mechanical advance while running in the cam. Because there is no load on the engine it doesn’t matter if the mixture and timing is a bit out. You’ll do far more damage to the engine, particularly the cam and followers, faffing about trying the get a reasonable AFR rather than just starting it and running in the cam without allowing the engine to idle. Whatever you do to the carb settings (and you can only adjust the lean best idle without changing jets) on any engine you’ll have to do again on another very different engine. Even two engines with identical specs could need different settings. I’ve never started an engine on a stand – I just don’t see the point, if you build it right you know it will run and if you don’t know if you’ve built it right you shouldn’t try to run it. All you can do on a stand is run in the cam, and YouTube clips of an engine making a noise while the owner blips the throttle.
