On the dyno, ported intake manifolds.....RPM 440 vs Victor 440

[IQ52]

What if I'm going to race my 500" 440 on the circuit or dragstrip and run it on the street, which manifold do I use, the RPM or Victor?

Well, what rpm are you leaving the line or pulling the corners? Because if you're lugging the engine you aren't racing! Horsepower is what makes a car fast on the race course and horsepower isn't found in the lower rpms where a street engine works.

Make up your mind, what are you going to do with this car!

Here is a pretty typical 496 with ported RPM heads, Lunati Voodoo solid roller 249/255 .585/.600, 10.3:1 compression running on 91 octane. What is the difference between the seriously ported RPM and Victor intakes with a standard 440 port window? We will run a 2" spacer on the Victor only, believe me, you want to run one, it makes a difference. This is assuming hood clearance means nothing as this is a hotrod street/race car.

rpm.......................RPM TQ/HP......................Victor TQ/HP

3000.........................541/309..........................522/298
3100.........................548/324..........................523/308
3200.........................570/347..........................545/332
3300.........................612/384..........................586/368
3400.........................614/398..........................594/384
3500.........................631/420..........................603/402
3600.........................639/438..........................612/420
3700.........................639/450..........................610/429
3800.........................638/462..........................610/441
3900.........................635/472..........................617/458
4000.........................639/486..........................616/469
4100.........................639/499..........................621/484
4200.........................628/502..........................618/494
4300.........................616/504..........................616/504
4400.........................611/512..........................614/515
4500.........................608/521..........................613/525
4600.........................607/531..........................614/538
4700.........................608/544..........................619/553
4800.........................607/554..........................621/568
4900.........................612/571..........................617/575
5000.........................609/579..........................629/599
5100.........................617/599..........................623/605
5200.........................614/608..........................619/613
5300.........................606/612..........................621/627
5400.........................597/614..........................609/626
5500.........................596/624..........................610/638
5600.........................590/629..........................605/645
5700.........................585/635..........................594/644
5800.........................578/638..........................585/646
5900.........................570/640..........................584/656
6000.........................550/628..........................568/648
6100.........................533/619..........................559/649
6200.........................535/631..........................551/650
6300.........................518/621..........................530/636

Unlikely average Joe will feel much difference driving these two set ups around on the street, the thrill will be the same with both. But go to the race track and the Victor is going to win the races. You can see the ported RPM is a really good manifold, there's no doubt. The Victor is the race winner and will be even better the higher you go into the rpm range. We just happen to be outta cylinder head and camshaft right now.

 

[383man]

Looks like the RPM wins up to 4300 rpm as thats where they match and the Victor takes over just like I would think. Thats one reason the RPM is a nice street intake and can still work ok at the track depending on the combo. Peak hp in a race car the Victor will win.
I can tell you on my sons Dart which is a .030 over 400 (406) he runs the MP .557 cam and basically stock RPM heads with 3.91's and a Dynamic 9.5 converter that flashes to about 4000. It weighs 3550 with him in it and I will post the ET's using the RPM and the single plane Holley Street Dominator :

RPM - 11.55 @ 116

Holley SD - 11.59 @ 117

You can really see it on the timeslip as in the 1/8 mile the RPM had it all over the single plane but in the last 1/8 you see the hp starting to make up the difference and catch up. The Holley SD did mph better but was almost 1/2 a tenth slower. Now if his Dart had a bit more gear the single plane may have had the better et. Thats one reason I went with the Indy dual plane on my 3700 lb 63 since its a 99% street car. I told my son he can use which ever intake he wants to keep and he said the RPM felt so much snappier on the street. And he is only making about 475 to 500 hp. From what I see the Victor made 10 more peak hp (650) to the RPM's (640). It does show how dominate the Victor is above 4300 rpm. It kinda proves the the facts that a heavy street car with not much gear and converter will like the RPM better but a track car with enough gear and converter will be faster and the lighter the car the better. I feel the Victor would be faster on most race cars that dont see below 4500 that much but some street cars will be faster with the RPM. Thanks for posting that. Ron

 

[coloradodave]

Yes, thanks for posting this. Very interesting. Looks like either one of those combinations in a car would really like to be short shifted in a drag race...

 

[kdtjb]

Does this mean it's time for another DYNO DAY? Hope I can make it, if it is.

 

[IQ52]

Does this mean it's time for another DYNO DAY? Hope I can make it, if it is.

Yeah, we're trying. This would have been a fun one. It was Torker II, Torker II w/ spacer, two different RPM intakes, Victor port matched, then with a spacer, Victor port matched and plenum blended, then with the 2" spacer, Victor port matched and plenum ported, and then the 2" spacer.

We're still trying to figure out what to do for another dyno day.

 

[Herr_Poopschitz]

A few observations and personal rules of thumb...

This is an off the shelf camshaft. Changing the valve events can make a dramatic difference in these #s as well. I try to stress the use of custom cams in custom displacements/induction pkgs. They don't cost much more and can offer substantial power and drivability benefits.

Taking a slight hit in torque can pay dividends on a car seeing street duty...i.e., traction.

Big torque figures are overrated. If a person needs more torque, swap gears.

IQ...you have a PM...

 

[bm02tj]

I would love to attend a dyno days if it lands 1 to 2 weeks before easter or 1 to 2 weeks after easter and it is set a mouth before so I can arrange
my work schedule I will hope and keep watching
Bruce

 

[benno440]

Jim is that my RPM intake?
that soem cool info, i dont think my car will see over 4500rpm often, so it might be a good choice for now and bump up to a victor as a spare down the track if i need it

- - - Updated - - -

will we see any benefits of a 2" 4 hole tapered to open hole carb spacer with the ported rpm intake?

ii have one sitting ready to go is all

 

[IQ52]

Jim is that my RPM intake?
that soem cool info, i dont think my car will see over 4500rpm often, so it might be a good choice for now and bump up to a victor as a spare down the track if i need it

- - - Updated - - -

will we see any benefits of a 2" 4 hole tapered to open hole carb spacer with the ported rpm intake?

ii have one sitting ready to go is all

Yep Ben, your intake. In the past on less horsepower engines there has been no gain. We didn't try it on this engine.

However.................The engine is still on the dyno and we may make some exibition runs for some family members this weekend................you just never know.

 

[benno440]

if you could try out a 2" spacer that would be great, let me know.
the main reason for the spacer is to get the air cleaner up into the reverse cowl scoop for the cold air seal to hood im setting up. if it makes power than great if it makes no difference then oh well

 

[dsd1967]

IQ52.....I'm curious about the commment of the 2" spacer on the Victor intake. What type of improvements have been seen at what rpm ranges. I know a lot depends on the engine combination...but is it pretty much an across the board improvement regardless of the combo? Also is the spacer you are using an open or 4 hole...and would there be a difference between the two?

I'm getting my Victor equipped 512 dyno tested in the next month, and I'll have him throw on a spacer to see what happens.

 

[benno440]

4 hole is for low end power and open hole for top end is what I keep reading, I bought one of the HVH supersuckers, they are 4 hole then taper to an open hole

 

[67 B-body]

IQ52.....I'm curious about the commment of the 2" spacer on the Victor intake. What type of improvements have been seen at what rpm ranges. I know a lot depends on the engine combination...but is it pretty much an across the board improvement regardless of the combo? Also is the spacer you are using an open or 4 hole...and would there be a difference between the two?

I'm getting my Victor equipped 512 dyno tested in the next month, and I'll have him throw on a spacer to see what happens.

Awesome Dave!!!!
Glad to hear your getting close..... Good luck!!!!

 

[benno440]

Jim are you doing some more tests before you send the intake?