Timing

01yellercobra · Oct 26, 2018

I've started playing with the tune for my son's 98. While looking through the BKT I noticed it was really low. It topped out at 11 degrees. But the the other two tables topped out around 25. What are you guys giving in your stock set ups? Mind you he's still running 87 as he hasn't started his new job yet.

2002BLGT · Nov 26, 2018

If on 87 fuel don’t go more than about 2 degrees over stock till you get better fuel in it

96blak54 · Nov 26, 2018

Adding timing means less volitilty. In other words ...having to ignite the mix earlier because of either poor mixture or slow combustion relative to rpm.

Im also not saying a little bit of tweeking wont help. What i am saying is the efficiency of these engines dont really need timing like the older pushrods. The stock setup could benefit from tighter fuel trims.

Im sure you understand flame propagation and flame travel relative to piston speeds and bore diameters. The smaller the piston the less timing needed cause flame travel across the bore is less. Throw on heads that produce in cylinder swirl like no other and your looking at an engine that doesnt need alot of advanced timing. Actually. ..to a stock engine, more timing really wont be noticed unless the mixture is rich or has higher octane, but if compression has not been increased the higher octane is not worth it.

Best thing to do is start reading plugs after a shut down from a hard high rpm run. Then start messing with the fuel trims and then timing will follow.

Truth be told, running the lower, much cleaner burning octane is a high positive compared to the dirty high octane. The ticket is If you can increase the compression while still able to produce stable combustion with 87octane. Like i have with 93octane and 13-1 static compression.

Take all this with a grain of salt

01yellercobra · Dec 2, 2018

I'm aware of the basics. I learned with a timing light and adjustable vacuum canisters. I just wanted to see what the guys that have played with these engines were running. I've been playing with 4V since 2005. So I'm used to those set ups.

I did manage to bump the timing a bit and help his throttle response. Oh, and helped him put a couple cars on his buddies 350Z to shut him up.

96blak54 · Dec 2, 2018

Sweet....nothing better than a great kill story from your son! I can hear me saying to my boys, "oh yeah, now we gotta pull the engine, up the compression, install lighter components, freshen it up"! Sadly tho, i dont think this will happen. My guys are ate up with guns!

01yellercobra · Dec 2, 2018

96blak54 said:
Sweet....nothing better than a great kill story from your son! I can hear me saying to my boys, "oh yeah, now we gotta pull the engine, up the compression, install lighter components, freshen it up"! Sadly tho, i dont think this will happen. My guys are ate up with guns!

Theres a PI engine on a stand in my garage. His plan is a budget upgrade as far as better pistons and Boss rods. Depending on how his work goes maybe some minor head work and cams. And eventually a Tork Tech kit because he likes the PD blower. The dream is to be faster than dad someday. I keep reminding him that I'm doing the tuning though.