This is interesting.

Those numbers look very nice.

Run a hydraulic "mild" cam and moderate compression numbers for an EFI engine, both with 3x2 throttle bodies, and a simple TB mounted on the CI intake. I imagine that a number of people might be interested in these two setups for resto-mod street cars? (I know that I am for the Zephyr if I have much more hassle with the Aussie XFlow).

I'm also thinking that the numbers on the EFI were what I'm looking to build in a turbocharged 250/CI head. That means it's really possible! :D

Ben
 
8)

What is more telling is that the EFI engines 335 lb-ft for 250 is 1.34 lb-ft per cube. That is a stunning torque figure which exceeds notible company such as the pre emissions quad cam V12 Lamborghini Countach LP 400, the early smog Twin cam XR6 Turbo, and any of the 4.0 and 4.2 liter Aston Martin and Jag twin cam engines, even with triple Weber DCOE carbs.

Best I've seen is 1.39 lb-ft on a special dyno Ford 4.0 SOHC engine, and 1.39 per cube is common on Fords BDA 1800-2000 engines. (Twin cam, four valves per cylinder).

This non cross flow engine is becoming more and more like an LS-1 at a third the price, there is a lot of power to be had before even adding a turbo!

Imagine scaling up that 335 lb-ft and 351 hp with just 12 pounds of intercooled boost. 600 lb-ft and over 580 hp can't be too hard.

When you look at the weight factors of a stout 250 in one of the lighter 2400 to 2800 pound Falcons, Mavericks and Mustangs, I can imagine the looks of Corvette C5 drivers when they've been shut down by an unturboed 250 with just the cam, head and carb package.
 
AzCoupe":2sna4333 said:
I was playing with the virtual engine dyno program, and loaded various builds for comparison. All are 250ci with n/a. Check out the results, ...
Click to expand...

Holy &#%@!!

AzCoupe":2sna4333 said:
... I wonder how close they are?
Click to expand...

You ain't the only one wondering that, brother!

:)

Looks like there's going to be some 6 cylinder Falcon and Mustang guys looking for some beefier drivetrain parts, stickier tires, improved suspensions and better brakes, and some 8 cylinder guys wondering how the heck they just had their @$$#$ handed to them by the 6 cylinder guys.

:)
 
Another point of interest, when changing from the OZ head to the CI head, it only gained 35hp and 28lbs of torque. But when I took full advantage of the new head (bumpping the C/R, a cam swap, roller tipped rockers, and a 4V carb) it gained 100hp and 98lbs of torque. Kind of hard for me to believe, but maybe. I'd love to get my hands on an engine dyno for a week or two. ;)
 
I'm looking at the numbers with the CI head and 2bbl carb and comparing that to Mustang Geezers last runs with the same setup. Considering he is having traction issues and is running a 200 and not a 250, those numbers look like that could be really close. I'm excited! :D
 
I've been sitting here studying the various configurations you chose and I am finding myself wondering how an engine would fair on the virtual engine dyno program if it were configured exactly like the CI-500 engine except instead of using a 500 CFM 2-V carb equip it with a vacuum secondary 4-V carb of appropriate size.

I'm not sure what the appropriate size would be, mind you, but I figure something somewhere in the 390 to 550 CFM range would do it, and anyway I guess you could play with the software and see what results it spits out.

:)
 
Guys a 4412-500 2bbl when converted to 4bbl flow ratings is only 354 cfm, the 7448-350 is 247 cfm.
I would like Mike to plug this into the virtual dyno.
206 cubic inch engine
CI head with back cut valves
390 4bbl
11.2 compression ratio
1.65 rocker ratio
the 278-@.050 228 degrees solid lifter camshaft with a 112 lobe center
V/R Bill
 
wsa111":deoprryc said:
Guys a 4412-500 2bbl when converted to 4bbl flow ratings is only 354 cfm, the 7448-350 is 247 cfm.
Click to expand...

Yeah, that's why I was thinking a modest 4 bbl carb on that CI-500 engine might help on the higher RPM portions of the torque curve a little bit. I'm thinking the 500 CFM 2 bbl might be a little bit restrictive on that engine when it's running "at full chat" as they say on the far side of the pond.

:)

wsa111":deoprryc said:
I would like Mike to plug this into the virtual dyno.
206 cubic inch engine
CI head with back cut valves
390 4bbl
11.2 compression ratio
1.65 rocker ratio
the 278-@.050 228 degrees solid lifter camshaft with a 112 lobe center
V/R Bill
Click to expand...

That sounds like a wicked little screamer.

:)
 
wsa111":3mv9l2ue said:
206 cubic inch engine - CI head with back cut valves - 390 4bbl - 11:1 compression ratio - 1.65 rocker ratio - 264/274-112*
Click to expand...

I ran the same setup on both the 200 and 250ci.

206ci (60 over)
with 200cfm
231HP@5750 - 229lbs@4000 - 14.95 @ 90.1mph
with 250cfm
233HP@5750 - 231lbs@4000 - 14.90 @ 90.3mph
with 300cfm
235HP@5750 - 233lbs@4000 - 14.86 @ 90.6mph
with 350cfm
237HP@5750 - 235lbs@4000 - 14.82 @ 90.9mph
with 400cfm
240HP@5750 - 237lbs@4000 - 14.76 @ 91.3mph
with 450cfm
240HP@5750 - 238lbs@4000 - 14.76 @ 91.3mph
with 500cfm - up
no change

with single TB (500cfm)
245HP@5750 - 240lbs@4250 - 14.66 @ 91.2mph
with single TB (600cfm)
no change

with triple TBI's (500cfm)
250@5250 - 280lbs@3500 - 14.56 @ 92.5mph
with triple TBI's (600cfm)
no change
-------------------------------------------------------
257.7ci (60 over)
with 200cfm
280HP@5750 - 277lbs@4250 - 14.02 @ 96.1mph
with 250cfm
283HP@5750 - 280lbs@4250 - 13.97 @ 96.5mph
with 300cfm
286HP@5750 - 283lbs@4250 - 13.92 @ 96.8mph
with 350cfm
289HP@5750 - 285lbs@4250 - 13.87 @ 97.1mph
with 400cfm
292HP@5750 - 288lbs@4250 - 13.82 @ 97.5mph
with 450cfm
295HP@5750 - 291lbs@4250 - 13.78 @ 97.8mph
with 500cfm
298HP@5750 - 293lbs@4250 - 13.73 @ 98.1mph
with 550cfm
299HP@5750 - 294lbs@4250 - 13.71 @ 98.2mph
with 600cfm
no change

with single TB (500cfm)
301HP@5750 - 294lbs@4750 - 13.68 @ 98.5mph
with single TB (600cfm)
302HP@5750 - 295lbs@4750 - 13.67 @ 98.6mph

with triple TBI's (500cfm)
311@5250 - 346lbs@3500 - 13.56 @ 99.4mph
with triple TBI's (600cfm)
313@5250 - 348lbs@3500 - 13.51 @ 99.9mph

-------------------------------------------------------
Summary
With this setup, the best carb would be around 400cfm for the 200ci, or 500-550cfm for the 250ci. However, it is best to use a smaller cfm carb operating at high efficiency, rather than a larger cfm carb operating at a lower efficiency. It is also better to use a lower cfm rating if you want bottom end power, but more cfm for the top end.

With triple TBI's, more power at a lower peak rpm & better torque curve.

When a dual plane manifold is used, the HP is about the same, but nice gains in torque. What puzzles me is about the same ET, even with the extra torque. Therefore I think we need to do some dyno test and 1/4 mile runs with the new intakes and a couple custom adaptors. ;)

I like to run some numbers with a turbo, but have no idea what to punch in. It ask for HP rating, CFM rating, and Efficiency. Any idea what these would be for a T4 with 10-12 lbs of boost?
 
Mike, thanks for the great info, very interesting.
237HP@5750 - 235lbs@4000 - 14.82 @ 90.9mph
with 400cfm
If you have time could you run 1 more program.
Same 206 but use your 274H cam which has 224 @ .050
With the 390 cfm carb. Thanks Bill
 
Ops, I goofed. I forgot to change the cam specs, so the numbers above are with a 264/274 cam.

Here they are with a H274/274, followed by the S278.

206ci (60 over)
with 200cfm
235HP@5750 - 231lbs@4250 * 246HP@6000 - 232lbs@4500
with 250cfm
238HP@5750 - 233lbs@4250 * 249HP@6000 - 234lbs@4500
with 300cfm
242HP@5750 - 237lbs@4250 * 251HP@6000 - 236lbs@4500
with 350cfm
244HP@5750 - 239lbs@4250 * 253HP@6000 - 238lbs@4500
with 400cfm
245HP@5750 - 240lbs@4250 * 256HP@6000 - 240lbs@4500
with 450cfm
245HP@5750 - 240lbs@4250 * 256HP@6000 - 240lbs@4750
with 500cfm - up
no change

with single TB (500cfm)
250HP@5750 - 243lbs@4750 * 261HP@6000 - 243lbs@4750
with single TB (600cfm)
no change

with triple TBI's (500cfm)
255@5250 - 281lbs@3500 * 267HP@5500 - 282lbs@3750
with triple TBI's (600cfm)
no change
------------------------------------------------
257.7 (60 over)
with 200cfm
286HP@5750 - 281lbs@4750 * 300HP@6000 - 281lbs@4750
with 250cfm
289HP@5750 - 283lbs@4750 * 303HP@6000 - 284lbs@4750
with 300cfm
292HP@5750 - 286lbs@4750 * 306HP@6000 - 287lbs@5000
with 350cfm
295HP@5750 - 289lbs@4750 * 309HP@6000 - 289lbs@5000
with 400cfm
298HP@5750 - 291lbs@4750 * 312HP@6000 - 292lbs@5000
with 450cfm
301HP@5750 - 294lbs@4750 * 315HP@6000 - 295lbs@5000
with 500cfm
304HP@5750 - 296lbs@4500 * 318HP@6000 - 297lbs@4750
with 550cfm
305HP@5750 - 297lbs@4500 * 319HP@6000 - 298lbs@4750
with 600cfm - up
no change

with single TB (500cfm)
310HP@5750 - 300lbs@4750 * 324HP@6000 - 301lbs@5000
with single TB (600cfm)
311HP@5750 - 301lbs@4750 * 325HP@6000 - 302lbs@5000

with triple TBI's (500cfm)
317@5250 - 349lbs@3500 * 333HP@5500 - 349lbs@3750
with triple TBI's (600cfm)
318@5250 - 350lbs@3500 * 334HP@5500 - 350lbs@3750
 
Mike, thanks very much for the information. The solid lifter cam seems to be a solid 10-15 HP gain upstairs. Also the peak torque is at a higher rpm.

I assume the cams were run straight up. If they were advanced 2-4 degrees i wonder how much in would help torque in the lower rpm ranges.

Again, thanks Bill
 
Clay Smith grinds the cam straight up, so I always run the programs with 4 degress of advance.
 
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