Good 408 combo?

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Badart

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Thanks for the article 340sFastback. http://www.hughesengines.com/TechArticles/6408416strokerdynotests.php
I am thinking about copying their 2nd 408 build. Is this a good streetable combo? Is hughes stuff good? I dropped off my virgin 360 block and virgin 587 heads at the machine shop yesterday and dropped by today to show him the specs on the cam and tell him which rotating assy I want to use. He says it looks like a good combo and that he would look at it closer later. He is in the process of cutting the heads for bigger 2.02 valves and prepping the block. My plans for the heads are a full valve job, blend the bowls and gasket match. I know that I am leaving some power on the table by running these heads, but he says that they are in great shape and his machining prices seem good. What do you think?
 
Here's my build: 408 Stroker , short block built by Hughes Engines

-Forged internals, H-beam rods, 10:1 pistons
-Hughes Engines main stud girdle
-7 qt moroso pan, high volume melling oil pump
-Edelbrock heads, with Hughes Engines stage III porting, 2.05 intake, 1.60exh
-Hyd. roller cam. 576/576 lift int/exh. 256/258 deg. duration
-edelbrock victor 340 manifold, gasket and port matched to heads
-750 Mighty Demon carb
-Hughes Engines 1.6 Aluminum roller rockers
-Gear Drive, w/ custom timing cover and electric water pump
-TTI 1 5/8" - 1 3/4" Headers

Dyno'd @ 532 HP/520 FT. LBS
 
I went to the shop today and he still had the dyno sheet saved on his computer. He did about 10 different pulls, this one shows a peak horsepower of 533 @ 5900 RPM. Peak torque is 513 @ 5100 RPM...

He didn't print me out the one before this one where he made a jet change, and I got 520 FT LBS. Anyways, heres the dyno chart.

dynochart.jpg
 
mopardude318 said:
Here's my build: 408 Stroker , short block built by Hughes Engines

-Forged internals, H-beam rods, 10:1 pistons
-Hughes Engines main stud girdle
-7 qt moroso pan, high volume melling oil pump
-Edelbrock heads, with Hughes Engines stage III porting, 2.05 intake, 1.60exh
-Hyd. roller cam. 576/576 lift int/exh. 256/258 deg. duration
-edelbrock victor 340 manifold, gasket and port matched to heads
-750 Mighty Demon carb
-Hughes Engines 1.6 Aluminum roller rockers
-Gear Drive, w/ custom timing cover and electric water pump
-TTI 1 5/8" - 1 3/4" Headers

Dyno'd @ 532 HP/520 FT. LBS
Click to expand...

Love the build, but my pockets are not that deep.
 
I am looking for an electric water pump what brand are you using?
 
Nice build ! i bet you can pick up 25 hp with a 950 hp carb, just a thought..
 
That's an interesting thought...If I had one at the time, I would have liked to try it while it was on the dyno...Maybe when it's in the car I'll do a chassis dyno, then swap the carb and see what happens...??
 
dont know how mcuh you spent on the demon carb mopardude318, but prosystems makes sweet carbs tailored right to your setup for a wicked price...if your thinking of a swap fill out their quote form and patrick will get back to you quickly with a price and setup for your intended usage
 
Jesse at Bigs carbs is something to think about.. he works well with customers and when ever i need Air bleeds he sends them right out to me
 
Hello , Interested. We have somewhat similar engines just got mine back
from speed shop and dyno yours making a little more power but my concern is my bsfc@6200 rpm is .50 and at 3900 rpm is .433 any thoughts? Slightly
smaller cam (comp hyd roller) 549 intake (242@ .05) 544 ex (248 @.05)
1.6 rockers (harland sharp) 10.2 comp
No port work eddy heads 416 cui. made 505 hp @5700 and 513 tq @ 4700
Love you engine
 
Mopar 408 Magnum
Engine Specs

408 Cubic inches
Bore 4.030
Stroke 4.00 Ohio Crankshaft 4340
Rods Cat 6.123 H-beam
Pistons Probe
Compression 11.5
Cam Comp XFI Lobe HYD roller (236/236 duration at 0.050-inch, 0..576/0.576-inch lift). Heads Edelbrock RPM Magnums Ported
Intake Mopar M1 single plane Ported
Comp 1.6 ratio exhaust roller rockers
Carb 1050 Quick Fuel
DYNO RESULTS Mopar 408 Magnum Stroker SuperFlow 901 Engine Dyno
STP Correction Factor Tested

RPM TORQUE HORSEPOWER
3200 491 299
3400 495 321
3600 496 340
3800 508 368
4000 509 388
4200 517 414
4400 522 438
4600 529 463
4800 532 486
4900 533 497
5000 532 506
5200 528 523
5400 522 537
5600 513 547
5800 501 553
6000 484 553
6100 477 554
6200 468 552
 
Now that is a motor !!!!!=P~ Just out of curiousity, what kind of headers are you running on that beast ? I thought I wanted to build a B stroker for my Demon, but the #'s you guys are posting out of these 408/416 LA are making me rethink this, especially since I would like to keep my P/S and blower motor.

:read2::read2::read2::read2::read2::read2::read2::read2:
 
these sb strokers want big cfm carbs, even a mild 408 can use a 850+ carb no problem.
 
How difficult would the intake to head port match be ? And would the intake mounting holes have to be welded/redrilled ?
 
The six pack will bolt up no problem if you're using LA heads. Ports are the same. Can be done with Magnum heads but some machine work is necessary for the bolts to line up. I'm planning a 408 with a roller cam block & LA heads.
 
bad - How deep are your pockets? The main things you want to be aware of: Using open chamber heads means to get compression you need a flat top piston. That means if you want to upgrade top end later you will need bigger chambers and that aint the way to fly. I'd rather sacrifice compression now for versatility later. So I'd run a dished piston. All piston choices should be forged. The heads will restrict, but you can use the cam to get more power from what you have. Conservative 4" stroke cams are high 230°[email protected]" lift. So you are loking for a decent sized cam. In terms of lift, the pushrod angle will lose you .020 of lift so you can account for it by running something in the .560 range. More if it's a solid flat tappet design. Make sure you head guy knows what cam you want to run... He'll need to cut the heads for dual springs. As was mentioned... Run a carb at least 850cfm dry flow rating. I typically run 870 wet flowed (about 18% more flow than a dry flow rated carb) on street 4" arm engine. Last, get it internally balanced. It will last longer and make more power for a small bit more money.
 
If you do run dished pistons, I recommend the step dish type. They have a step that fills part of the combustion chamber on open chamber heads. If you ever swap to closed chamber heads, you'll have to get the step milled down for piston/head clearance. But, if you plan on going to closed chamber heads, then go with either flat top or regular dished pistons to save the cost and labor of milling the step pistons.
 
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