Annular booster carbs

[travis]

I’m still tweaking on the tune on my old truck, but I’ve got to say this is hands down the most responsive carb I have ever used on one of these mild truck engines that I primarily build.

I installed a vac sec 600 with annular boosters on my ‘83 ford with a mild 351w (9:1 compression, ported E7 heads with stock valve sizes, 206/221@.050 cam installed on a 109 ica, etc...low $$$ rebuild). Most people recommend these carbs for engines with low vacuum to help with street manners...this engine is anything but low vacuum (19” at 750 rpm idle). Throttle response is absolutely fantastic off idle...much better than any number of 600-750 carbs I have used on similar builds. Top end doesn’t feel any different (it’s not important on a farm truck anyway).

Why wouldn’t you use or at least try one of these carbs on a non racing mild build? Especially in a heavy vehicle?

It also seems to like about 4* less intial/total timing, otherwise I’m getting some pinging in the midrange. Is this a normal characteristic with these type carbs?

[bigfoot584]

Don't forget your talking to car guys, that's the old well if big is good then bigger has to be better.

Myself I agree big time it all about velocity, period.

[427dart]

I’m still tweaking on the tune on my old truck, but I’ve got to say this is hands down the most responsive carb I have ever used on one of these mild truck engines that I primarily build.

I installed a vac sec 600 with annular boosters on my ‘83 ford with a mild 351w (9:1 compression, ported E7 heads with stock valve sizes, 206/221@.050 cam installed on a 109 ica, etc...low $$$ rebuild). Most people recommend these carbs for engines with low vacuum to help with street manners...this engine is anything but low vacuum (19” at 750 rpm idle). Throttle response is absolutely fantastic off idle...much better than any number of 600-750 carbs I have used on similar builds. Top end doesn’t feel any different (it’s not important on a farm truck anyway).

Why wouldn’t you use or at least try one of these carbs on a non racing mild build? Especially in a heavy vehicle?

It also seems to like about 4* less intial/total timing, otherwise I’m getting some pinging in the midrange. Is this a normal characteristic with these type carbs?

[427dart]

I’m still tweaking on the tune on my old truck, but I’ve got to say this is hands down the most responsive carb I have ever used on one of these mild truck engines that I primarily build.

I installed a vac sec 600 with annular boosters on my ‘83 ford with a mild 351w (9:1 compression, ported E7 heads with stock valve sizes, 206/221@.050 cam installed on a 109 ica, etc...low $$$ rebuild). Most people recommend these carbs for engines with low vacuum to help with street manners...this engine is anything but low vacuum (19” at 750 rpm idle). Throttle response is absolutely fantastic off idle...much better than any number of 600-750 carbs I have used on similar builds. Top end doesn’t feel any different (it’s not important on a farm truck anyway).

Why wouldn’t you use or at least try one of these carbs on a non racing mild build? Especially in a heavy vehicle?

It also seems to like about 4* less intial/total timing, otherwise I’m getting some pinging in the midrange. Is this a normal characteristic with these type carbs?

Would that carb be a 4180 series 585 CFM that was used on the 84-85 5.0 Ford engine ?
My 85 Mustang LX 5.0 came with one and after some tuning was the best small carb I had ever run. It had the annulars in the primary and standard straight leg boosters in secondary. Ran 12.60's at 109 with that carb plus like you said throttle response was great!

[shiftbyear]

It possibly might need richer jetting for your midrange/cruise driving. The factory carbs are lean to pass fed. emissions. That is if you have the 4180 style as 427dart suggested. Ported heads, cam, and ditching the cats plus ethanol added fuel may required extra fuel. Ford did their homework on these carbs. Good luck.

[travis]

This is a 4010 style carb sold under the Summit name. They also offer this style in a 750 size.

I’ve got a 4180 (I believe that’s what it is anyway) off of my old ‘79 F150 that came stock on the 460. Unfortunately the throttle shafts are seriously sloppy, so I haven’t used it on anything else

[GARY C]

I’m still tweaking on the tune on my old truck, but I’ve got to say this is hands down the most responsive carb I have ever used on one of these mild truck engines that I primarily build.

I installed a vac sec 600 with annular boosters on my ‘83 ford with a mild 351w (9:1 compression, ported E7 heads with stock valve sizes, 206/221@.050 cam installed on a 109 ica, etc...low $$$ rebuild). Most people recommend these carbs for engines with low vacuum to help with street manners...this engine is anything but low vacuum (19” at 750 rpm idle). Throttle response is absolutely fantastic off idle...much better than any number of 600-750 carbs I have used on similar builds. Top end doesn’t feel any different (it’s not important on a farm truck anyway).

Why wouldn’t you use or at least try one of these carbs on a non racing mild build? Especially in a heavy vehicle?

It also seems to like about 4* less intial/total timing, otherwise I’m getting some pinging in the midrange. Is this a normal characteristic with these type carbs?

The annular booster better atomizes fuel and thats not always good on a hot intake and could be the reason for pinging, some dyno test show a lose of power on a hot intake vs cool intake.

I prefer a VS carb for street if you don't have a lot of converter and gear, most people over look spread bore or quadrajets due to the "big dbl pumper makes more power mind set" but if a carb is sized and set up properly the power and drivability will be there.

Holley use to make a spread bore 800 and was a good carb for drivability and power.

[travis]

It is a vacuum secondary carb (maybe it’s the 4011 style, I can’t remember). I wish I could run a spreadbore, but I haven’t figured out how to get the ford kick down to work properly with one. I have a box of q-jets and a 9895 Holley 650 spreadbore that are great street carbs

[shiftbyear]

Ford had quadrajets on the 429 cobrajet cars with automatics, a bit pricey now. I think 1970 and 1971, 7040286,7040288, 7041286, 7041288 may be the numbers.

429-super-cobra-jet+rochesters-quadrajet.jpg

[cjperformance]

I’m still tweaking on the tune on my old truck, but I’ve got to say this is hands down the most responsive carb I have ever used on one of these mild truck engines that I primarily build.

I installed a vac sec 600 with annular boosters on my ‘83 ford with a mild 351w (9:1 compression, ported E7 heads with stock valve sizes, 206/221@.050 cam installed on a 109 ica, etc...low $$$ rebuild). Most people recommend these carbs for engines with low vacuum to help with street manners...this engine is anything but low vacuum (19” at 750 rpm idle). Throttle response is absolutely fantastic off idle...much better than any number of 600-750 carbs I have used on similar builds. Top end doesn’t feel any different (it’s not important on a farm truck anyway).

Why wouldn’t you use or at least try one of these carbs on a non racing mild build? Especially in a heavy vehicle?

It also seems to like about 4* less intial/total timing, otherwise I’m getting some pinging in the midrange. Is this a normal characteristic with these type carbs?

Would that carb be a 4180 series 585 CFM that was used on the 84-85 5.0 Ford engine ?
My 85 Mustang LX 5.0 came with one and after some tuning was the best small carb I had ever run. It had the annulars in the primary and standard straight leg boosters in secondary. Ran 12.60's at 109 with that carb plus like you said throttle response was great!

Yeah they are a great carb, they should have done the same style carb also in a 700 to 725 cfm size