I don't know how I miss checking the inductive delay in the initial set-up of my Holley Sniper TBI. I knew something was wrong with my tune & lack luster ET & MPH.

This all started when I had to recently pull/re-install the intake manifold/distributor. I was going through the steps of setting the timing. When revving the motor, the timing was retarding 6*. I started going through the Holley instructions & found the below paragraph. I guess I didn't see it because they didn't list my distributor in the instructions.



Anyway, I had to change the inductive delay from 100 usec to 350 usec to correct the issue. Now I have to re-baseline my tune/timing table. I know I need more timing according to the ground strap, but not so sure I need the 6* I've been missing out on.

I'm hoping to get the tune better during the upcoming Thanksgiving race(s). While I'm in a good spot for racing, ET & MPH in the Pro class; 5.80's/118 mph & 9.20's/144 mph with max of 12 lbs. boost. I think I have a decent amount of ET & MPH left on the table with the lack of timing, even at this boost level. 

2BKING

Are you using CNP or distributor/ ignition? If distributor, what ignition box? What is triggering the spark? You did use the static timing set function to set, correct?

Here’s my HP setting using a crank trigger and Holley Hall Effect pickup sensor. The cam sync comes from a dual sync distributor. I set this at 4k rpm steady and revving from idle.

My engine is N/A and I dislike Holleys spark control so I use a second pickup that Grid uses. Holley controls the fuel and Grid controls the ignition.

I use the Holley Hyperspark distributor/ignition. The distributor has a hall effect sensor. Yes, I used the static timing set function.

2BKING

I’m sure you’ll get it re-tuned and happy you found the problem. Keep us updated.

quote:

Originally posted by markemark:
I’m sure you’ll get it re-tuned and happy you found the problem. Keep us updated.

Thanks M&M!

I wish I had more confidence with this system & having a boosted motor. I've been taking baby steps in tuning, especially on the timing.

I don't know if I'm looking at the timing table right to correct for the inductive delay discrepancy. I hope I can explain my thoughts on it correctly or show you. Here's the timing table I was using with one of my last data logs overlaid with the inductive delay retarding 6*.

What I'm assuming is I have to subtract 6* from each cell during the run & that was the actual timing. So, at the end of the pass I was roughly at 18* of timing, even though the table is showing 24*. I coming to the right conclusion here?



2BKING

quote:

Originally posted by B KING:What I'm assuming is I have to subtract 6* from each cell during the run & that was the actual timing. So, at the end of the pass I was roughly at 18* of timing, even though the table is showing 24*. I coming to the right conclusion here?

I’d agree. To be sure, subtract 6* from all the relevant cells and make a pass. It should perform the same as when the Inductive Delay was set to the smaller value.

I'd also confirm from others that use your system what Inductive Delay they are using just for a comparison. Seems extreme to me , but what do I know..lol

Thanks!

I did some research with setting/checking the inductive delay with the different Holley systems, because I thought it was excessive. It seems the default setting is 100 usec. A good friend has a terminator system & his is at 180 something.

I had done some research before I adjusted it some was in the 200 range & I found one that was over my setting. Heck, I don't know.

2BKING

M&M,

I made a post in the Holley Forums under the Sniper section about the perceived excessive usec.

Also, I'm going to re-check the timing tomorrow. I do have the MSD timing light I'm checking with.

2BKING