getrdunn

I can’t remember…. Are you currently reading each cylinder or left and right bank. I was shocked how far off cylinder to cylinder can be in various induction builds. Was that smitty who touched on some here or another thread?

Panther

Yes, WOT. I thought I read previously that you were upper 11.s in your target tables and then recently raised it to 12:1. Right about low 11s you're washing the cylinders down. Oh well, maybe I'm mistaken what your settings were.

PROP STAR

Right about low 11s you're washing the cylinders down ??

Was on the phone with Bob Teague yesterday for an hour while on the dyno with a 8.3 and he said tune the motor for 11.3 and 12. for just cruising & I seen no signs of washing cylinders down during any of 11 pulls .

Panther

How much power are you making.

AFR is a pretty arbitrary number depending on the power and the amount of boost. It also depends on what makes the engine happy with which is why these engines need to be dyno'd. But if you're running low 11's with a relatively low amount of boost, I'd say that's pig rich and not doing yourself any favors. Also, if you're low 11's on the dyno with dyno headers, you're probably even more rich in the boat (what exhaust was run?) What size engine do you have and how much boost? That will shed some light....

Panther

This one at just under 1200 hp on a 548" with 12psi did not like an 11:2:1 tune. It wound up running its best in the upper 11's.

ICDEDPPL

I don`t want to start a pissing match but the idea that at 6000rpm and a huge load that there`s unburned fuel washing cylinders down seems crazy to me.
We`ve run low 11`s for years.
at high 11s one cylinder might be 11.3, the next one might be 12.4 as gethhhrrrdone mentioned, fuel distribution in TB injection can be horrible, that`s why I want a 10 02 dyno this time around .

I was low 11s switched to mid 11s (doesnt really mean anything when I`m only monitoring one bank)

it`s the 12.5 at cruise where I went too lean. Old tune was high 11`s . That`s where my damage happened, but in reality the lifters took a $hit at the same time so I`m not really sure what the caused what.... but the other engine scored cylinders so that leads me to believe pistons got too hot from detonation.


I like what Tyler Crockett recommended but run mine richer at wot and 8psi .

MILD THUNDER

Sometimes we can learn alot from looking at what the oem's do. Then take it from there.

Buy when it comes to washing cylinders out, not a chance that under load/boost and 5000-6000rpm, there is any liquid fuel being slung against cylinder walls and washing oi

Ever see the sheer amount of liquid fuel being jammed in a methanol/alky or even E85 setup? Way way more than gasoline.

if an engine has too much timing, it will like richer afrs. Too little timing , leaner afrs. Tons of variables even on a dyno.

Panther

I would tend to agree with Tyler as well. I run about the same buy then tune if based on plug readings and EGT combined with afr. In terms of your cruise. Were you in boost at 12.5? Also, whats timing at at those cruise rpms?

Seems like with your blower spinning slow with distribution on the big blower maybe you leaned out a cylinder. But still, low 11s on pump gas is pretty darn rich and not doing any favors. Alky is a different ballgame.

The last blower engine I dyno'd a few days ago started breaking up ignition at 10.9:1 on the first pull. Once i got AFR tuned correctly up into the mid to upper 11's torque went from a measly 600ft lbs to 730 ish @ 4k.

What lifters werw you running? Was that on the Comp HUC cam you had? How many hours?

abones

So let me say this, O2 readings and AFRs in whatever range you my think is optimum is all great but I learned and was blown away by reading plugs that those #s can hurt . READ THE PLUGS during Dyno testing.!

I'm sure everyone knows this, I just wanted to bring it up again food for thought!

ICDEDPPL

I read my plugs after every weekend and they seemed fine .
I mean you guys tell me, obviously I`m not good at reading plugs but I sent pics to people that said this was fine but I could use more timing .. with boostane they all come out yellow so that makes it even worse ...



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