Hot Rods 3x2's vs. 4x2's on a Flathead

3x2's vs. 4x2's Contest​

Hi Everybody,

As part of the dyno testing of a customer's flathead, we ran the engine normally aspirated with an Offenhauser 3x2 manifold with three Stromberg 97's and then we used the same carburetors (plus an identical unit) on a Weiand 4x2 manifold on the same engine. For both series of tests the maximum ignition advance was 26 degrees, but the jetting was optimized for peak horsepower for each setup. So just for fun, I'm having a contest to see who can guess the peak horsepower made by each setup. More about the engine and the contest can be found on www.roadrunnerengineering.com .

To enter, just email me ( roadrunnerengr@msn.com ) your estimate for peak horsepower for each setup, example; 180 hp for the 3x2 setup and 200 hp for the 4x2 setup. That's all you need to enter! The winner gets $50 and the runner-ups get free books. The dyno data and the winners will be posted on the above website after the contest ends on October 15, 2010.

 

I don't want the 50 bucks so I'll just wait for the results. I never saw a 4 duece equipped flat motor less than full race that could handle 4 carbs. only one I ever saw on the street was a 50 ford with a full race 53 merc that was killer till 1957-58

 

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Max1 cam is pretty mild. I would guess that the gist of this is that the result defies conventional wisdom and came as a surprise to the people involved (after all, if it did what was expected, we probably wouldn't be talking about it), so I would guess that the 4x2 made the most power.

 

If anyone can guess the horespower this 4x2 rig makes, they get to pay ME $50...

 

Have a perusal through this thread:

http://www.jalopyjournal.com/forum/showthread.php?t=164109

 

I'm running a Weiand 4x2 on my 304" 8BA thats being built now

 

Now how the heck are we supposed to take even a wild *** guess when you haven't given us the specs on the complete engine package I know, I can go to your site (maybe that is the point) - but why not just post it here. Without the rest, this is like throwing a sausage down an alley - who knows where it will land!

Post the following, then I'm willing to guess:

1) Bore, Stroke
2) Cam
3) Valve sizes
4) Ported relieved, etc.. - and to what level . . . mild, street, full-out race, etc..
5) Heads and compression ratio

 

Ignition also..
Duane

 

Step test or acceleration test?

 

A little more on the engine (some of this is on the website):
1) bore & stroke, 3-5/16 x 4-1/8, heavy duty center main cap
2) Street port & relief
3) Max1 cam, 1.6" valves
4) EAC iron heads prepared as in my book, 81 cc .
5) Mallory Dual Point

 

A flathead what?

 

Hi Joe....good to hear from you. I'm still working on the blower install on my 52 F-1. Side-tracked with a T-10 install. Catch ya' later.

Tom H.

 

Well hell . . . tell us what is in it so we have a fighting chance

 

Why not just beg people to visit your website?

 

I guess a negative 6hp..Hope I don't win..
LOL uncle max..
Duane.

 

Well, I'll get the estimates going. The motor isn't really too racy, but I think Joe probably gets some ponies out of it. Maybe 184 hp for the 3x2 and 192 hp for the 4x2.

It's been a long time since I had a flatmotor, and it was never on the dyno, so take these as flat-out wags.

 

234 and 248
what's a flathead?

 

I'd be interested in the numbers for a 2x2 intake also. Hell throw a single lung on there for comparison.

 

Go to your room.

 

LOL..Your the best..I'm wondering if my garage is a room??
Duane...

 

Wondering how 'optimistic' his dyno is versus others? I've heard some pretty big numbers before on other folks dynos . . .

How about a baseline number and combination so we have a clue as to how your dyno compares to others?

 

One of the reasons why I asked if it was a step or acceleration test...

 

Uncle Max,
that motor is a 296'er that came up with
242 HP @ 4900 rpm, 272 ft/lbs @ 3800 rpmat motor

 

I built a 3/8" X 3/8" (296 CID) for a customer in 1984. He insisted on using this "Space-Age" Isky Max1, after I went to all the trouble of a week-long portand relief job, Chrysler valves, and Lincoln springs...
3 Strombergs on a Weiand intake, and 9.75 Edelbrock heads, jets were 48 centers, and 44 outers. Harmon & Collins Ducoil ignition, two Blue Streak finned coils...
I installed it in his '40 Ford Tudor, ran it in good, and handed it over to him.
He drove it a week, then came by and said, "It doesn't seem like it's got 296 cubes...It doesn't have the power your flathead has."
I drove it. He was right. It didn't have enough power to pull a greased hat off a bald head.
I subs***uted a Weber F2. (had it for years) Valve lash .008" & .014". Drove it. Scared myself. It ran like a striped-a$$ed ape. I told him to be careful of the transmission.

 

Bingo, we have a winner! I'll be expecting my 50 bucks right away ;>)
Seriously, Tony Baron built the motor - my small part was cobbling the carbs together. Four 48's with the best HP made using .045 mains with # 65 pv's.
The motor is on the water, headed for Australia.

 

If you left that Isky MAX1 in there, I'd guess the dyno has been drinking.

 

mine has a 4 3/8" **** crank, boar to 3 5/16" 302 cubic inch, JR 400 cam and 4 stombergs on a edelbrock intake
came up with 219hp at 5000 RPMs

 

Except for break-in testing, all of our power pulls are ramp type, where the computer controls the load so that the rpm increases at a fixed rate, like 300 rpm/sec. Saves engines! The computer then adjusts the data based on the inertia of the rotating system (engine, dyno absorber, etc) to simulate th output from a step (fixed rpm) test. All modern dynos that I know of have this capability.

 

All modern dynos have the capability, but they also have the capability to step test, which is one (of several) good ways to get an inflated number. Just wanted to know what procedure was used, so I know the testing regime that was used to generate the numbers. After all we are trying to guess a dyno number via long-distance, just trying to eliminate as many variables as possible. Thanks for the response.