 Carb Question on Big Type 4, V8's use them, why can't a Type 4 use a 4 barrel |
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| tracks914 |
 Jan 18 2008, 08:05 PM
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Canadian Member  Group: Benefactors Posts: 2,083 Joined: 15-January 03 From: Timmins, Ontario, Canada Member No.: 153 Region Association: None   |
I like the air intakes on the FI Type 4, nice smooth pipes. Why do we have to put 4 carbs on the big type 4's to make them work?
Being an old V8 builder and racer I was wondering why we couldn't put a nice 400 CFM 4 barrel carb on a Type 4 with FI manifold and make it work just as well as 4 individual carbs? Is it the size of the carb? Does it have anything to do with running some cylinders leaner/richer because of air cooling? Mixed fuel is mixed fuel and if the ratio is right then it should burn just as good? Maybe Jake can chime in and explain. |
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| So.Cal.914 |
Jan 18 2008, 08:56 PM
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"...And it has a front trunk too." Group: Members Posts: 6,588 Joined: 15-February 04 From: Low Desert, CA./ Hills of N.J. Member No.: 1,658 Region Association: None |
I believe it has to do with thats a long way to send air and fuel, especially
horizontally. It would end up pouring into the cylinders. |
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| McMark |
Jan 18 2008, 09:11 PM
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Two words:
Long Runners Too much time for fuel vapor to turn into fuel droplets. Fuel droplets don't burn. |
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| Jake Raby |
Jan 18 2008, 09:36 PM
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#4
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
The V8 places the intake dead center of the cylinders, this arrangement is the second best for a V8 second only to those same Webers we use mounted as 4 pair in the center..
The problem with the TIV or any flat engine configuration with a single carb is the runner length and the fact that there is zero heat to warm up the intake over the center of the case. The cold runners and the super long distance from the carb to the intake valve make for horrible tuning and flat spots from hell that can't be tuned. There is a reason why there was NEVER a Type 4 engine that came from the factory with a single carb... Never judge performance on size. Design trumps size most every time. |
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