I finally got the 541 all buttoned up and ready to dyno. Moparts member sr440 is kind enough to let me make a mess on his dyno tomorrow.


So, what does the brain trust think? I'm pretty sure I got the cam and all the pistons in there so it just might run.

4.50 crank
4.375 bore
10.5 compression
Edelbrock performer heads with a full CNC job
Hydraulic roller 235/241 cam with 589/571 lift 112 LSA
Comp roller rockers
Old Weiand tunnel ram converted to front facing port injected intake
1700 cfm throttle body
2" dyno headers will be replaced with my 1-7/8" headers when it goes in the car.Don't want to smoke the ceramic on the dyno.


The idea behind this thing was to have an oversized cruiser with stupid amounts of torque with HP being whatever it wants to do.

What's your guess on power?

i'm gonna guess about 550lb-ft at 2500-3000rpm and a peak at about 4200rpm, maybe the peak will be about 620lb-ft
hp around 550hp, maybe 5300rpm?

this one will be interesting. not your typical build..

550 +/- @ 5300, 650 ft/lbs @ 3800. Flywheel horsepower.

If it's anything like my 493 it will fall off a cliff shortly after peak power but my RPMs are pretty much OOTB with the exception of a good valve job.

Kevin

My take on it is.......
The Weiand TR is too small to support 541” at any kind of higher rpm, so I’m expecting to see a pretty big TQ number, then the HP will peak pretty early.
As a result of the early peak the HP number won’t be all that big.
I’m thinking the TQ/HP numbers will end up pretty lopsided, towards the TQ end of things.

To throw some numbers out there(which will be a total “WAG”), 660-670ft/lb, 550-560hp.

In order to know how the basic long block combo compares to “the rest of the world”, it would need to be tested with a “known quantity” induction on it.

I'm going to say vey close to 700 ish TQ very early & 520 to 540 hp

i'm not going to guess any numbers because i'm not smart enough to come up with any.
however, i will say i think the torque will move that imperial out in a way bigger step than you might think.
i'm waiting for driving impressions after the engine is installed.

The intent of the build was to make silly amounts of torque over a usable range. HP was never a concern. It was going to fall into the Rolls Royce range of "sufficient".

This thing needs to pull down the highway at 1700 rpm and still have a full normal rpm range.

It's an unusual build for sure.

Mechanically, the upper limit of the usable rpm range will likely be determined by the valvetrain.........although the hp peak should occur well before that.

If it peaks between 5200 and 5500 I'll call it a proper job.

The Imperial needs a high torque low rpm engine but I didn't want a tractor motor.

You should have your answer in about 24hrs

mine made 725, buddy son made 705. less stuff than ours. i will guess 645 hp and 605 tq.

Cam is small so that will restrict the power but you should have great torque. I'm going with 650 torque and 525 hp as a guess. Hopefully it starts, runs good and doesn't leak. If it does those three then it is a successful dyno day. Fine tuning can always take place down the road. Are you confident of the EFI tune at this point or will you need to dial in that tune on the dyno?

No guesses, but Good luck with it, hope it runs well for you.

It's your cam so it's all your fault anyway.


When I've discussed the build with other engine builders they like the combo.

People have to understand that it's not a horsepower build. This thing needs to have a strong vacuum signal, be happy lugging a 5300 lb car down the highway at 1800 rpm, idle fairly smooth, and make absurd torque everywhere in the rev range.

I'm pretty sure it'll do all that.

I'd be happy with that torque and maybe a wee bit more hp. Maybe 540?

Rich Nedbal from FastmanEFI.com will be remoting in to build the tune.

Hopefully all goes well and you're happy with the results!

There is probably some power in opening up the ports in that tunnelram. The question is, how will it affect the torque you prize. I like your build.
At first I thought it might be limited to low 500 hp teritory. But it might surprise us. I will guess 560 hp. max torque 660 at 3400? No matter what, you are going to love the way this deal runs!

660 lbft, 575 hp

Going to make at least 1hp/ci, I'd guess just over 600hp, and high 600's for torque. S/F....Ken M

Ringer alert