Dyno #'s HP 500
 

just got a call from my engine builder - (rebuild my carb HP500's) pulled 571 @ 5000 & 608 ft torque @ 4600 - these are preliminary #'s without tuning. I'm going over there after work to check it out - how do these #'s sound???

Re: Dyno #'s HP 500
 

If you just kept everything stock and simply freshened them up I say it sounds very good.

I just dynoed one of my 500 EFI's last week. We changed the heads to World Merlin II's, Rect Port 320 CC. Bumped the compression fro 8.75:1 up to 9.1:1 and kept everything else stock. Of course freshened up the entire motor.

These are the dyno numbers.

4300 RPM HP= 526.9 Torque = 643.6 Ft Lbs (Max Torque)
5200 RPM HP= 598.0 Torque = 604.0 Ft Lbs (Max HP)

The rev limiter kicked in and it was still making horsepower.

Hope this helps for a comparsion.

Doc

Re: Dyno #'s HP 500
 

stock heads with some port work & new cams - (freshened up)

Re: Dyno #'s HP 500
 

not sure of cam specs - (I'll find out) but the second run was even better
5000 Rpm hp 588 tq 618
5200 602 608
5400 615 598
I'll try & post my dyno sheet

Re: Dyno #'s HP 500
 

impressive :D

Re: Dyno #'s HP 500
 

Looks graeat!

Re: Dyno #'s HP 500
 

Looks great!

Re: Dyno #'s HP 500
 

Dock and Ran,

I believe those look to be good power numbers on both of your engines! I would sure be happy with those numbers if they were my 502's!

Re: Dyno #'s HP 500
 

yeah baby!
tell us more about your set up.... what cams and did you have the heads flowed, if so what kinda numbers did you see.
interested for comparison...im sure there are several of us here thatd love to see them while we're still building!!!
thanks
kevin

Re: Dyno #'s HP 500
 

:d

Re: Dyno #'s HP 500
 

#'s - I'll get the details from my engine builder for cam specs. He is very well known for his head port work.

Re: Dyno #'s HP 500
 

Final #'s 5400rpm 608.6 tq 625.8 hp :D

Re: Dyno #'s HP 500
 

Doc,
Did you keep the stock throttle body or did you install a larger one like the one's that are on the 525's.? Also what about the reprogramming of the ECU.

I'm changing my heads and adding the A/S throttle body to my 500EFI's. I should say I'm adding the entrie 500 EFI upgrade kit from A/S. If I make 550 HP and pick-up some additional Torque from my bolt on I will be happy.

Re: Dyno #'s HP 500
 

Doc any ECU work? nice numbers Ran Dom 32

Re: Dyno #'s HP 500
 

No ECM work. My guy has done this before and says the Merc ECM is VERY fat. We are going to keep a very close look at the plugs when we water test. If things don't look good we will do some ECM work at that time when we bump the rev limiters up.

Re: Dyno #'s HP 500
 

VERY NICE NUMBERS!

Congrats

Re: Dyno #'s HP 500
 

Yes, both stock cam and stock throttle body.

Re: Dyno #'s HP 500
 

I am curious, what does a 500efi pull on a Dyno brand new?? Is it just 500hp?? I think you gains are awsome but damn 100+ hp for just working the stock heads? You make me want to pull my 500efi and do it :D

WILL

Re: Dyno #'s HP 500
 

Supposed to be between 500 and 517 HP will, out of the box.

Re: Dyno #'s HP 500
 

I am putting 525EFI Cams, cometic .027 gaskets and Iron Eagle 308 heads on mine. 9.38CR, 120 Thermostat, Big flow numbers on the heads, See Nordic Section