Carb upgrade?????

[NATEHAWK]

I'm looking to upgrade from my 4 barrel 1406 600cfm to a Holley 650cfm with mechanical secondaries. Right now my car stands with a 351W dual plane ford intake with a set of world windsor sr. heads. I'm sure it's a mild cam just can't remember the exact model. THOUGHTS????

I think with just the upgrade of that carb should wake my car up even more. Not looking to do any really major engine mods at this time. I'm really focus on getting the body work and paint done.

[zoomie]

http://www.prosystemsracing.com/index1.html check these guys out

[johnunit]

those guys have a great rep^


Why mechanical secondaries? Generally a bad idea for a street-driven car this heavy without serious gear and/or converter.

[zoomie]

not only do they have a great rep, ive seen them in action, and they are streetable, my buddy ran a 10 sec car on the street with one, not to mention almost all the x275 guys i know run them lol

[NATEHAWK]

those guys have a great rep^


Why mechanical secondaries? Generally a bad idea for a street-driven car this heavy without serious gear and/or converter.

After looking further into it I think your right. Without having a lot of gear and having a heavier car the unit with vacuum secondaries seems to be best.

[P72Ford]

In my '87 coupe, with the mild 306, and a 3200 stall converter, the 600 DP is fantastic. With that carb and converter, it is the definition of throttle response.

Alot of folks say that heavy cars and mechanical secondaries do not mix. But if its a pleasure car (not a DD), I would always recommend the MS. The fuel mileage will suffer, but I have multiple first hand examples of folks that are elated with a MS carb on a heavy car.

My buddy has a '69 Cutlass with a very well built 350 Olds. Ported #5 heads, radical cam, long tubes, etc. It has a mild converter, and stock 2.XX rear gears. We assed around with a 770 Street Avenger on that car for a long time, and it was always lazy, and pokey. As an experiment, we tossed on a 750 DP we had laying around. Romp it from a stand still, and the tires will go up in smoke until you lift. It was an entirely different car after we swapped to a MS carb. And his car is no lightweight. Its a full trim street car.

[NATEHAWK]

In my '87 coupe, with the mild 306, and a 3200 stall converter, the 600 DP is fantastic. With that carb and converter, it is the definition of throttle response.

Alot of folks say that heavy cars and mechanical secondaries do not mix. But if its a pleasure car (not a DD), I would always recommend the MS. The fuel mileage will suffer, but I have multiple first hand examples of folks that are elated with a MS carb on a heavy car.

My buddy has a '69 Cutlass with a very well built 350 Olds. Ported #5 heads, radical cam, long tubes, etc. It has a mild converter, and stock 2.XX rear gears. We assed around with a 770 Street Avenger on that car for a long time, and it was always lazy, and pokey. As an experiment, we tossed on a 750 DP we had laying around. Romp it from a stand still, and the tires will go up in smoke until you lift. It was an entirely different car after we swapped to a MS carb. And his car is no lightweight. Its a full trim street car.

What you think about these:

http://www.summitracing.com/parts/HLY-65-4777/?rtype=10 < No electric choke thou

http://www.summitracing.com/parts/HLY-0-76650BK/ < This one seems to have it all

http://www.summitracing.com/parts/DEM-1282010/ < No eletric choke

[turbo2256b]

With a high stall it the down side of a double pumper on a heavy car is overcome to some extent. With little to stock stall your betteroff with a vacuum secondary. Typicaly a smaller DP is recomended than a vacuum secondary by around 50 to 100 cfm in the same application.

[NATEHAWK]

With a high stall it the down side of a double pumper on a heavy car is overcome to some extent. With little to stock stall your betteroff with a vacuum secondary. Typicaly a smaller DP is recomended than a vacuum secondary by around 50 to 100 cfm in the same application.

Well right now I'm just trying to get a lil more power out my car as it stands. So what carb would you recommend to swap out for my edelbrock 1406. It's only a 600 cfm.

[turbo2256b]

Is your intake the Performer or the Performer RPM? What is the max RPM you shift at?

[NATEHAWK]

Is your intake the Performer or the Performer RPM? What is the max RPM you shift at?

Dual Plane Performer. My 1-2 shift can hold till just a tad under 4k.

[Lincolnmania]

i thought that was the ford racing dual plane for the 351w nate.......did u change it?
the cam specs it was a sealed power rv cam, sorry cant remember exact specs, we built that 351 almost 20 yrs ago lol

[turbo2256b]

Think the Ford racing intake was the Performer RPM Eddy if I remember correctly.


Have to wounder about that cam should be able to hit 6K roller or flat tappet. What did you use for valve springs? Any body remember thier specs?

Just want make sure nothing else is holding you back. Those heads are not the best but but they are not crap either and should do well on a 351

[turbo2256b]

Are you doing the L D L shuffel to hold it

[NATEHAWK]

i thought that was the ford racing dual plane for the 351w nate.......did u change it?
the cam specs it was a sealed power rv cam, sorry cant remember exact specs, we built that 351 almost 20 yrs ago lol

Yea it's the ford racing one but has the same specs as a performer.