Holley EFI Timing tables. Can anyone share what they run. I am interested in values that everyone is running on NA setups.Here is mine on 502 with afr heads.

Mine was supercharged so I don't know if it'll help any

If you send me your email I can shoot over my HEFI file...


Doug

Can you post one with PSI instead of kpa..

I can tell you this, when I dyno they usually like more like around, 28 in midrange approaching tq peak (below it) and 32, 33 w afr heads after 4800, 5000(I think thats what you told me you had for heads, Smitty)

Personally what my motors wants for timing is still a damn mystery to me.
30* at 4000 and 2# of boost or 27* ?? I have no ducking clue lol.
This past weekend I made a switch to add 3* of timing , (at any speed)
was data logging it , adding 3* and seeing if rpm increased indicating the engine likes it .. but I would need calm water (not happening on lake michigan) and a bunch of time to get this testing done .
I think next I`ll pull timing and see what happens.

Data log: Purple: timing switch on
Yellow : timing
Green: RPM
29* at 4000 increased to 32* not change in rpm. Maybe it wants less than 29*
Only thing I noticed is the EGTS dropped 20-25* but that don`t tell me a whole lot

Artic you do a lot of dyno testing , any info you can share ?





The bump is a wave
Timing goes up (yellow) but RPM never changes (green)

less timing will raise the egt's,,if anything,,go up a degree or 2.you won't see much in speed or rpm,you'll just make your exhaust valves happy.
I usually dyno tune for the timing table and get the afr's some what correct.then in the boat I make the afr's right and leave timing alone,unless i'm bouncing off the knock sensor.

can you give us more info on cam specs, compression etc? idle area should be about the same otherwise you start surge and it makes your IAC work overtime and I wonder if you are using idle timing adjustments or if you have the turned off. also you sheet should basically be lock out and not growing otherwise you are not getting the best out of your engine.

if egt drops when timing is added then you were under timed. You have to look at dimisnishing return for egt vs deg.

Hi Guys, was hoping you may be able to help me, i know its a big ask but i too have gone down the Holley Road - (and i have no experience at all) I was after some help with timing curve, i have been talking a lot with the guys on the Holley forum and they have been very helpful where they can, but most don't understand boats, and as far as I'm aware total timing on my marine engines ( i have twin setup) should come early in the RPM range for torque. (6 Tonne Searay)
By no way is my setup high performance, i did it for reliability, i always cruise at 3000 - 3500 RPM.
If it helps i have Twin 454,s with new Dart Eagle Iron heads (Dual spring setup) (i know i coulda done better) I ditched the Distributors and have Holley / MSD Cam Plug sensor, Crank Sensors and Smart coils all with Holley HP ECU.
New JE Pistons and Im at approx 9.5 :1 Compression and i use Premium unleaded fuel (By the way I'm in Australia).
I have them running but the guys on Holley site want me to find what the timing curve for the original motors was. Originally Merc 454 Mag MPI Horizon EFI.
If not maybe a safe timing curve so we can enjoy the fruits of all our work...Cheers Aaron...

Post #4 is what you want. 28° Midrange/cruise/planing 32-34° 3/4-Full throttle.