Carb Orientation

Tech chat w/ Marc Matzer
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Marc
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Carb Orientation

Post by Marc » Thu Feb 21, 2008 10:50 am

When doing carb swaps or engine swaps,attention must be paid to the angle at which the carb is sitting in the engine bay,otherwise rich/lean issues will occur.Float direction or oreintation is critical with carburettors and their ability to work correct on your engine.
Example,putting an 850 engine in a 600 is a great swap,but the manifold must be beveled to get the carb sitting level again because the 600 tranny has the engine now mounted on an angle of about 15 degrees off center.This will tip the fuel in the float bowl and not cover the emulsion tubes correctly causing it to run rich and lean depending which way you turn the steering wheel!This can't be remedied by adjusting the float only.
Another example is trying to mount DCNF webers on a 124/2000 engine.Float position is critical here again.Works great on a Beta engine mounted transversely,but will run rich/lean in corners and rich in a straight line accelerating on a 124,the fuel bowls lifts up flooding the tubes or too dips too far down turning left,because of the natural force of inertia from the car moving,which in turn has an effect on the float moving.
Check this out before selecting carbs or doing an engine swap or carb upgrade.Floats should sit inline with the foward motion of the cars travel.

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allenlofland
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Post by allenlofland » Thu Feb 21, 2008 5:04 pm

Marc: Are you just tryng to see if I'm watching hehe.
I will remind you that Bayless sold a DCNF kit including cams for the 124 Spider for years and there where lots of them used. No Problems for street use. I will also remind you that As I mentioned before. I had a discussion with Pierce about this and they recommended that the dcnf although as you state , sitts wrong, there should be no problems with the DCNF sitting "WRONG" for the street. Pierce believed that the dcnf would be fine up to the point of "Off Road Rally" That would be a NO GO.
I have also mentioned before to you that the Bible of Webber books, I call them the green books by a guy , whos name I can not pronounce and book presently being in storage can not go look it up. Calls for the DCNF's on a few stock Italian cars sitting :Wrong"
I point this out BECAUSE, i KNOW THERE ARE SOME STILL OUT THERE that
Bayless and otheres sold. I think we should be carefull to condemm something that might just be ok and not cause some poor guy to run and spend big bucks to corrrect his car wnen there is nothing wrong with it.
Just trying to keep you on your toes Marc :)
Allen & Lynette Lofland
Wichita Kansas
Back on Land with Our Fiat :)

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Denise
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Post by Denise » Thu Feb 21, 2008 5:55 pm

Hey Allen! Good to see you're still around. I have heard about the fuel starvation problems with the dcnf on Spiders from others. Maybe they're driving the cars with a little more spirit than intended? Also, I have a Bayless book from way back. It does mention the carb setup for the 124 Spider but there is no write up. It seems this setup is preferred for the X19. I don't really know since I've been running the idfs. Is there anyone here that has had the dcnf setup on their Spiders that can chime in?

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allenlofland
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Post by allenlofland » Thu Feb 21, 2008 6:02 pm

denise: Dont think for a minute that I am recommending the
dcnf's for the Spider. I think the rumors you hear are from those that dont have any real world experience with the dcnf's in such a use. I had a friend long departed that auto crossed a hot 124 coupe with 42 dcnf carbs and 43-83 alqauti cams. He sold me the set up when he retired the car do to rust and abuse on the track.
His experience with the dcnf's on a 124 is what got me curious, I used the cams in my Scorpion.
Its just another Fiat Legend :)
Allen & Lynette Lofland
Wichita Kansas
Back on Land with Our Fiat :)

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Denise
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Post by Denise » Thu Feb 21, 2008 6:17 pm

What did you do with the carbs? Have you tried them on your car? I'd like to get a set of those Alquati cams.

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allenlofland
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Post by allenlofland » Thu Feb 21, 2008 7:09 pm

Denise: When we moved aboard the boat I had to get rid of lots of stuff, I think they went on ebay at that time ????
Cams come up on ebay all the time, you just have to be ready :)
40/80s most common and great cams, I love Alquati cams, they just look good out of the box :)
Allen & Lynette Lofland
Wichita Kansas
Back on Land with Our Fiat :)

Marc
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Carbs

Post by Marc » Thu Feb 21, 2008 7:28 pm

You want to buy a set of 42s cheap?I tried them along time ago,beleive me they dont work right,and I dont want to get anyone in trouble who sold them... because I'm personal friends with them.Besides the orientation being wrong,the no#4 mix jet rubs against the master vac unit,you cant get the carbs to open all the way with any known linkage and they are simply wrong for the car,IDFS are the only way to go on the street.Allen I'll buy you diner at your favoirte rstaurant,your choice if I'm wrong...

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allenlofland
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Post by allenlofland » Thu Feb 21, 2008 7:37 pm

Marc: What manafold are they on. ?
the ones I had had no clearance problems.
I only eat at expensive places . 8)
Allen & Lynette Lofland
Wichita Kansas
Back on Land with Our Fiat :)

Marc
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Intake

Post by Marc » Thu Feb 21, 2008 7:45 pm

Alquati intake,depends on the condition of the motor mounts on how close it gets to the master vac.. but will rub and break if you drive it aggressively.
That makes two of us who likes good food, I might buy anyway,I think it would be fun to talk to someone with your Fiat knowledge...I was wondering where you went...I knew you weren't going to let this one slip by.

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allenlofland
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Post by allenlofland » Thu Feb 21, 2008 8:20 pm

What do you want for those carbs and manafold. :wink:
Allen & Lynette Lofland
Wichita Kansas
Back on Land with Our Fiat :)

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