Speed Secrets: Understanding Timing For Your Best Tune

[@thedobermangang3503]

what should my vacuum gauge read with a camshaft thats alittle bigger than your stock cam ..i have a 1990 k5 blazer 350 engine it has rebuild with up graded the cam to a howard rattler cam intake lift 225 exhaust 535 duration 227/235 lobe separation 109 centerline 103 i check to see how mush vacuum i were getting and its no where near 19 to 21 of mercury .. the needle is in the red area sitting on 10 where it say late value timing or leak at intake manifold or heat riser my engine has about 480 miles on it

[@TURBOTRISTO]

So say you have a n/a car that has say 15deg standard if you turbo charge that engine do you reduce the timing? To say 13 deg or increase it to 18deg as a rule of thumb?

[@dsauce8780]

To me thats entirely dependent on how you are running your fuel. A rich mixture will help you avoid detonation, keep the engine cool, but it takes longer to burn. Because a rich mixture takes longer to burn, and is less likely to detonate, advancing the timing on a rich mixture is a safer way to achieve your HP goals. If you are targeting a lean mixture this gets slightly more complicated because the burn time is very short and it burns hot. Goes off like a grenade. If you have a very stout engine with an immaculate cooling system you can stuff many a psi at >12.5afr and make tons of power(and heat) without very much timing advance.

[@TURBOTRISTO]

@@dsauce8780 thanks for the info mate

[@dsauce8780]

@@TURBOTRISTO raise hell.

[@TurboTony101]

Can you explain how and why advancing the timing increased the horsepower or why boosted applications start lower etc etc this vid left me with more questions rather then answers lol

[@joshtheking1772]

Dont forget spark plug temp and gap on the next video when talking about timing. We dont need any holes in the pistons around these parts

[@KingJT80]

Also heat range in the plugs. They change too

[@joshtheking1772]

@@KingJT80 yup, colder.

[@tonybailey89]

I'm wondering if 12-15 deg of ignition timing is being retarded on my Stage 2 tuned 2.0t turbo engine? This is with 93 octane fuel?

[@drloch6174]

yep

[@mortensandmoen5208]

Whay dont use knock sensor for optimal timing?

[@TomarenaiEraserRain]

Because you don’t want it to knock. The sensor detects a knock. Being conservative with timing, and staying away from the threshold keeps it safe.

[@mortensandmoen5208]

@@TomarenaiEraserRain OK. But you newer get the optimal tune...

[@dsrocks6905]

​@@TomarenaiEraserRainyou want to be just under that knock threshold, that's why you have a knock sensor. If you ain't knocking, you ain't trying

[@russelljackson7034]

Right on

[@petejoseph8257]

547 from a 408 on an engine dyno? That’s not very much for a 408. 241 heads?

[@darviin9470]

Next cam timing

[@KingJT80]

So add timing until it pings or loses power?

[@hurttech7593]

The latter, sometimes. Keep in mind this isn't always about adding timing. Its all matter what you start with and what the motor likes best. Generally you do start with lower timing advance and then work your way up because it's safer however sometimes you end up retarding the ignition from your starting point. This video didn't do a good job explaining why and kinda pushes the notion that advancing timing will always make more power, this is just not the case. The best timing is where the motor makes the most power since it's not fighting itself. Too far advance and you are igniting the mixture too early and the combustion gases start to push a bit as the piston is still coming up or at least not in the optimal position (this could be as much as 70 degrees after top dead center). This doesn't always mean detonation, you can have too much ignition timing well before you hear knock. Imagine pedaling a bicycle. You want to push down on the optimal point to maximize your effort. If you try to push down too early the bike might still move forward however you are wasting energy in the process. Make sense?

[@KingJT80]

@@hurttech7593 oh yeah makes sense. I've seen people say both. The people with no dyno are using the first one but if you can get on a dyno the 2nd one seems to be way more accurate

[@TravisFabel]

I'm very disappointed in this video. When I saw him I thought he would explain how he ramps up and finds his limits to safely run timing. Instead this entire video can be summed up as "timing is important and can make more power if done correctly"... With absolutely no discussion about how you can quickly break a motor or how to do anything.

[@isawul00k]

Of course you're gonna make more power spinning a SC 400more rpm up top

[@davidaames8787]

The sound on this video is freaking me out

[@unclesquirrel6951]

Personally I blame squirrels

[@liamlouis3063]

This video has no sound

[@ThatNofbody]

Yea it does

[@antipasinchrist]

Can this guy ever get "pound-feet" correct when speaking about engine torque? Or is he just going to mangle it forever with "foot-pounds?" Annoying af

[@guthrie1181]

Settle down bro

[@nathanielmackinnon6738]

GUTHRIE #1 😀😀😀

[@kevinjohnson9372]

Lol as long as u know what he means that's all that matters

[@charlesgreathouse7376]

Who cares?