View Full Version : Recent engine build dyno results
Thought I’d share a recent build I helped put together for a fellow FFR owner. He’s rebuilding one of the very first MK 1’s. This engine is an all aluminum 434 Cu. In. Windsor. Originally built by Keith Kraft in 2001. It dropped a valve so it was pretty trashed. We rebuilt it with AFR heads and Borla stack injection with Holley HP ecu. It’s got 10:1 compression and a pretty mild cam so it should drive very nicely. Attached are a couple of pics and the final dyno results. I have been curious for some time how much HP the air filters would cost on the stack systems. This was a perfect opportunity to find out. I had 2 sets of filters to test, the little screen inserts that fit inside the stacks and the larger filters that go over the top. I was pretty shocked at the results. On the graph the light green and blue lines are running no filter, red and dark blue are the large filters and dark green and grey are the screens. That’s around a 30 HP loss at 600 Hp, however I’m sure lower HP engines would not see as great a loss. Interesting nonetheless.
Bob
cgundermann
07-08-2022, 08:30 PM
What a beast!
Chris
nucjd19
07-08-2022, 08:59 PM
Thanks for the info! That is a work of art!
Very nice, Bob. It's amazing what those filters do to the power. Regardless, I'll be running filters on mine to keep the rocks out of my valves. I'm having the car dyno tuned next week. I'll be very interested to see the numbers at the rear wheels compared to the flywheel numbers from BPE when the engine was built.
Dave
Dave[/QUOTE]
Try a dyno pull without the filters if you get a chance, it'd be nice to get the data. When I was running the little screens I found pebbles laying on top several times. Definitely wouldn't run without something.
Bob
I rebuilt a mild 351 a couple months ago. He had chassis dyno'd it at 370 Hp. I ran it on my engine dyno after the rebuild (no changes) and it made 435 at the flywheel running full exhaust and all accessories. Of course chassis dyno's vary a lot, but that should give you an idea. What altitude will you be at?
Jim1855
07-08-2022, 11:19 PM
bobl,
Nice motor. Great power. 600 is a nice number, 'bout right in the sweet spot.
I'm running an aluminum 427 but down about 60 hp from what you've shown. I know all about dropping valves, did that once, didn't like it at all. Makes a mess, costs lots of money to rebuild. Has great street manners with a carb, the EFI will help smooth things out especially the low-speed drivability.
Jim
I rebuilt a mild 351 a couple months ago. He had chassis dyno'd it at 370 Hp. I ran it on my engine dyno after the rebuild (no changes) and it made 435 at the flywheel running full exhaust and all accessories. Of course chassis dyno's vary a lot, but that should give you an idea. What altitude will you be at?
That's about what I assumed. My flywheel number from BPE was 438 and I assumed that would be more like 375 at the wheels. My house is at 6100 ft., but the tuner is probably closer to 5200ft. My priority is drivability over peak power, so we'll see what we end up at.
Here's a different dyno run that has all the data from the ecu included in case anyone is looking for more specific results.
Bob
seanbrown427
07-09-2022, 08:05 PM
I have to thank Bob for all the help rebuilding and getting that engine going. It was quite a journey. Now I'm updating the frame and suspensionv on old #83. I'm even going with a coil near plug setup to eliminate the spark plug wires on the top of the motor. It's been a lot of work and Bob Lloyd was amazing.
I spent today updating the front suspension and brakes. Attached are some photos.