Vintage Mustang Forums banner

1 - 5 of 5 Posts
G

·
Guest
Joined
·
0 Posts
Discussion Starter #1
This is really making me mad. Which would produce more HP, big block dual plane (8v) or tri-power (6v)? Why or why not?

BTW, does anybody have a code "D" 427 SOHC that I can buy? Hehehehehe.....I smell the ricers burnin' as we speak.
 

·
Registered
Joined
·
4,609 Posts
First, you are confusing "dual plane" with "dual quad". Edelbrock Performer and Performer RPM's are examples of "dual plane" intakes. Dual Plane intakes allow for longer runners, thus more torque, but less high RPM power.

Now on to your question. The answer is "it depends". As with any engine, it depends what RPM range you want to build power in. If you are talking ultimate power at high RPM, I would guess dual quads would be the way to go.

In a street car where low end is important, I would guess that a tri-power would shine as it would have fewer CFM opening immediately off idle.

I must temper the above with the fact that I have zero experience owning or tuning a multi carb car. (I have riden in a few Mopars but that is about it. BTW, the fastest was a 440 GTX with a tunnel ram and dual quads.)
 

·
Registered
Joined
·
1,258 Posts
Found the following ad for ya:
_____________________________
For Sale: VERY complete matching numbers 427 with matching numbers 2-4 barrel Holley's, and 4 speed tranny. It was in an old show car and has less than 5000 miles since new! It has Mallory ignition, headers, cam and valve springs etc., Hayes steel bellhousing with the dual bolt pattern, Hurst shifter, and it is in Cobra trim, (valve covers, air cleaner, oil pan, etc.) It is together and complete with all pulleys, linkage, fuel log, fuel filter, etc. from the fan blades to the output yoke for the drive shaft, and from the air cleaner to the deep oil pan. It even has the original Autolite alternator and chrome brackets! I am asking $6,500.00 OBO for this beautiful Cobra engine and tranny. Please e-mail me at [email protected], or call 716-432-8228, or 716-627-5198 for more details. I would be more that happy to disassemble anything on the engine for inspection for a prospective buyer with a 50% down payment.
________________________________________________
 
G

·
Guest
Joined
·
0 Posts
Discussion Starter #4
Err....my fault. I meant. Which one would allow more torque and HP, 8 barrels or tri-power 6 barrels? I am confused. I was hoping for a massive street HP setup for my big block I'm getting soon.
 

·
Registered
Joined
·
3,997 Posts
Dual 4V: Likely to create the highest HP and more RPM
6-2V: Likely to create the greatest torque at a lower RPM given the greater fuel atomization

Note: This is assuming all things are being equal....

Now let's talk equal: 2V & 4V carbs CFM are not calc'd the same way. To achieve/calc equal flow, you must multiply the engines required CFM by 1.4 when applying 2V carbs. A good street engine making all its HP by say 5500 rpm and all its torque by say 3000+ rpm will stomp all over a race engie which makes the same HP at say 10,000 and torque at say 6000 rpm.

I would suggest establishing the max RPM you wish to make your max HP at, then state your desire to maintain a flat torque curve throuought that range, then determine the CFM needs. While todays new manifolds with a single carb really flow alot better than almost anything (style) from the 60's or 70's, the classic look of dual quads or tri power does look cool, attracts a crowd and either can be made to really, really run well. Unless you're at the track, you would probably have a hard time telling the difference inperformance if both were properly set up.
 
1 - 5 of 5 Posts
Top