Club Cobra - HP Estimate??

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FE experts:

I am running a 428 CJ in my new BDR. Now that I finally have it sorted out in time for winter driving season :D and it has never been dyno'd, I was wondering if anyone out there can give me an estimate with my engine setup. After perusing several threads, I am guessing I am somewhere around 460 HP and TQ.

Here's the skinny:

Heads: Edelbrock FE Performer RPM Cylinder Heads
Cam: CompCam-hydraulic flat tappett. Duration 230/236 @0.50 , lift .562/.565
Carb: Quick Fuel HR780. 780 cfm w/mechanical secondary
Intake manifold: Edelbrock performer RPM
Pistons: Diamond dished pistons bore 4.185,stroke 3.984,6.49 rod,1.675 cd for 10.17" deck height
Hydraulic Lifters: Comp cams fe high energy hydraulic lifters
Crankshaft: Eagle cast steel crankshaft 3.984 stroke.
Block: 1967 428CJ Ford Service block
Roller Rockers: Pro Comp Aluminum roller rockers
Push Rods: Smith Brothers 4130 chrome moly custom
Connecting rods: 6.490" Eagle "ESP" H Beam Forged
Rings: PBM Power Seal Rings
Rod Bearings: Clevite P-series rod bearings
Compression Ratio: 10:1

Most likely more info than you need, but I wanted to be complete. I plan on getting the car on a dyno this spring/summer to determine the RWHP then add about 15-17% on top of that for an estimate at the crank. Uhtil then just working on completing my documention.

Thanks **)**)

I'd say 450-460hp would be a good estimate.

I would look into another brand of rocker arms. The Pro Comp stuff is known for failures and I've personally seen a set seize up on the dyno.

sounds good to me i would say 450hp

I'll go with 450.5 hp :D

Brent, thanks for the heads up.....I had my engine builder set up an engine for street use as I have no intentions of racing the car. We have an MSD rev limiter set at 5000 RPM so I don't break anything.:eek:

Does that setup change anything with regard to the pro comp rr's?

Unfortunately no, they will fail at any rpm.

The last failure that I saw was on the roller tip on the rocker arm. It completely seized up and it wasn't for lack of lubrication.

Since then, I've seen a distributor die and a set of their SBC cylinder heads with the valve cover bolt holes drilled in the wrong spots.

I would consider swapping them when the next chance arises. There are several good quality choices that won't break the bank.

The rest of your parts are good solid parts. I wouldn't worry about breaking anything. With your heads, cam, and intake, you're probably making peak hp at around 5500rpm, so you're missing out a little bit if you have it chipped at 5000. ;)

Easy to fix the revs, I'll look into it when it gets a little warmer.

What roller/rockers do you recommend? I'll talk it over with my engine builder.

Once I get another 100 miles on her, it's going back to him for final tune and checkout before being cleared for duty, so if a change needs to be made it would be perfect timing.

Thanks for the help!

Is this in the car or dyno??

BDR879 If we are doing the dyno thing, and you say nothing about head or intake work, I will go with 415 HP and 480 torque. Put this in the car and at the rear tires you are in the 300 hp and about 370 of torque. Alot of this depends on the exhaust system and how much back pressure is formed killing power. I had a 452 with about the same numbers except compression. It will be enough to have you smile and scary the crap out of you. :eek::rolleyes:;):D gear ratios in the trans and rearend are going to give you the preformance you are looking for. Rick L.

Since we are speculating on this - I saw a couple restoration 428 CJs at Keith Crafts shop a couple months ago that had been run in on the dyno. I assume they were 100% stock but blueprinted. The dyno operator said from memory that they made around 415 HP. I asked how much Edelbrock heads would make on top of the heads on my engine which are basically the same as Cobra Jet heads now that they have been re-worked with larger valves, and they guessed about 30 HP on my fairly mild motor. So assuming your engine was put together with the same attention to clearances and part matching, that gets you up to about 445 HP. With the intake and cam figure another 10 to 15 HP and my guess is 455 to 460.

Dan

I suppose I can jump into the guessing game. I'll bet on the low side - likley around 400-420 at the flywheel. But you'll never be able to back calculate that from a chassis dyno. The numbers from those machines are only useful from a tuning comparison viewpoint on the same machine, same day basis - and have little if any real meaning.

what cam to make this 450- 475 hp

witht his combination what cam would he need to make 450 plus hp? Would a solid lifter cam do it....comp 282s or 294s??
Jon