48 Dellorto blow through hesitation at transition
- brookester
- Posts: 444
- Joined: Sat Apr 23, 2005 11:53 pm
Re: 48 Dellorto blow through hesitation at transition
I don't have much to go on here but the areas I would be looking into would be bigger idles, bigger pump jets or smaller venturis or a combination of the three. That would just be to clear the stumble when you stab the gas....and that's assuming your fuel pressure is right. You need a wideband for sure. Don't run it lean on boost. Better to start out too big on the mains and work down.
Only do one change at a time.
Only do one change at a time.
- brookester
- Posts: 444
- Joined: Sat Apr 23, 2005 11:53 pm
Re: 48 Dellorto blow through hesitation at transition
I just went back and read your other thread on this subject and it sounds like this has been covered.
Just to give you an idea I used 32mm venturis on my 2161 draw through to get the air speed up and it still made 250 hp. you might need smaller venturis than 30mm. Your wideband will help you when you get it. you never know it could be too rich.
Just to give you an idea I used 32mm venturis on my 2161 draw through to get the air speed up and it still made 250 hp. you might need smaller venturis than 30mm. Your wideband will help you when you get it. you never know it could be too rich.
- brookester
- Posts: 444
- Joined: Sat Apr 23, 2005 11:53 pm
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Re: 48 Dellorto blow through hesitation at transition
It seems I got it fixed I had a small vac leak. Im currently running 10 psi but the afr is not as rich as I would feel safe at. Should I go to 200 mains from 190?
- brookester
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- Joined: Sat Apr 23, 2005 11:53 pm
Re: 48 Dellorto blow through hesitation at transition
What is your afr reading?
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Re: 48 Dellorto blow through hesitation at transition
13.9 in 2nd gear at 3500 rpm @ 10 psi
- brookester
- Posts: 444
- Joined: Sat Apr 23, 2005 11:53 pm
Re: 48 Dellorto blow through hesitation at transition
It can't hurt to try it.
How cold was it outside when you took your afr reading? That makes a difference.
How cold was it outside when you took your afr reading? That makes a difference.
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Re: 48 Dellorto blow through hesitation at transition
Mid 40s. I still dont really trust my afr. Is it really displaying at the moment readings? It seems when engine warms up and your driving that its always running a little rich but not to much. It feels that all it reads is twmp(which It does right?)
- brookester
- Posts: 444
- Joined: Sat Apr 23, 2005 11:53 pm
Re: 48 Dellorto blow through hesitation at transition
You might need to try the modulator rings. I know mine runs like poop without them.
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Re: 48 Dellorto blow through hesitation at transition
Do mod rings help up top or down low?
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Re: 48 Dellorto blow through hesitation at transition
They help on boost, RPM is irrelevant.
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Re: 48 Dellorto blow through hesitation at transition
And what happens if I dont use them?
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Re: 48 Dellorto blow through hesitation at transition
You might not get boost enrichment, though some have said you only need to boost reference the float chamber.
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Re: 48 Dellorto blow through hesitation at transition
And I assume by boost referncing the float chamber you mean putting the rubber hose that clonebug did on his build and just like brookester shows on the pic he posted? The hose between the main jet stack right?
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Re: 48 Dellorto blow through hesitation at transition
bump. Guys doing dell/weber blow through need to read this. I'm giving blow through another try.
I think I'll crack it this time.
I think I'll crack it this time.