Engine flatlines/jumps

UR50SLO

UR50SLO

V6+2=LSXCamaro
Re: Engine flatlines/jumps

running 93 with methanol.
Click to expand...

Are you running meth right now? if so turn that OFF. Turn the boost all the way down.

When tuning and having problems it's best to start with basic's. Low boost... safe fuel safe timing.

Once you have clean acceleration at that point then start adding boost and meth back in.

Have to walk before running.

I normally take care of ALL my driveabilty first.. idle.. part throttle cruze AFR's then move on to WOT at

the very last. The most important is the driveability since that's where you spend most of your time.

~Scott
 
qbnkiller

qbnkiller

Conflaguration Specialist
Re: Engine flatlines/jumps

I agree with Scott - walk before you run. I also think its a great idea to dial it back a few notches, unplug the knock sensor, and see what it does.
 
UR50SLO

UR50SLO

V6+2=LSXCamaro
Re: Engine flatlines/jumps

qbnkiller said:
I agree with Scott - walk before you run. I also think its a great idea to dial it back a few notches, unplug the knock sensor, and see what it does.
Click to expand...

4399317815_b8c6ff1e01_o.gif


Yea buddddddy.:tup:
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

would you guys prefer DM logs, or TP logs?

cause i have a stockpile of TP logs with no knock and the truck flatlining. Dyno pulls, 1/8 mile, 1/4 mile, street crusing, whatever you want.
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

if the above mentioned doesnt work. Would it be worth the while to download the starter BIN again, and paste in my Fuel/Spark tables, and leave the Constants/Scalars at what they are.


Also, is there a way i can tune the knock sensor out. If i set the threshold high, or set the ESC retard to 0, so that when it knocks, i can see it on the datalog, but it doesnt affect the tune. I'm leary about disconnecting it, cause i still wanna see if it does knock.

BTW, running solid mounts does give knock readings. lol at least for me.
 
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Big Mike

Big Mike

New member
Re: Engine flatlines/jumps

Try .035 spark gap you are running an Msd, on a n/a car wider gap is better for Rpm. Possible your truck needs wider gap. You still need that alky control box pic I can get that for you I never touched the pots yet and is set to stock.
 
UR50SLO

UR50SLO

V6+2=LSXCamaro
Re: Engine flatlines/jumps

Big Mike said:
Try .035 spark gap you are running an Msd, on a n/a car wider gap is better for Rpm. Possible your truck needs wider gap. You still need that alky control box pic I can get that for you I never touched the pots yet and is set to stock.
Click to expand...

Anytime my gaps are wider than .30 we get spark blow out. Even with MSD. The Magic

number is 10psi on our truck.. anything more than 10lbs and it blows the spark out.

I've tried 3-4 sets of plugs all with same results. Our poor spark energy combined with

poor combustion chambers just blows the candles out. Tick's me off since I can roll with

.35gap in the Buick GN's no problem.

He should have the spark plug gap at .28-.30max.
~Scott.

OH.. but to answer your question on not allowing it to spark retard yes.. you can 0 out

in the constants/scalers your ESC Maximum allowable Retard. I think that should not allow it to take timing out. It's set at 18.11 right now.
 
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Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

i had them at .030 when i first put the engine in, and since then i've been running on .024
 
Big Mike

Big Mike

New member
Re: Engine flatlines/jumps

How are your grounds have you ohmed them out lately? Anybody else using the same cam you are using, what are their results? Do you have the injector mod done, switching the wires on the ecm to use both drivers, what about ecm voltage mod with the relay to get more voltage to ecm helps under wot? is this with open down pipe or full exhaust?
 
91blazins10

91blazins10

Active member
Re: Engine flatlines/jumps

I'll wait for Brandon to chime in on how this evening went :rotf:


ps red loctite is your friend.
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

Well found the knock problem. All 8 bolts on holding the caliper backplate to the rearend housing came loose, and the passenger side came apart. Luckily under Pats skilled expertise, we were able to nurse it back to his garage and replace the bolts.

On a side note, i learned a couple things. If i leave the truck in a certain gear, and slowly roll into the throttle, it'll wind up good. But it seems like as soon as i hit WOT it hesitates. Running on Pats tune it hesitated about 5500. When i put mine back in for the ride home, i noticed i could progressively give it throttle and it revved good, but if i stomped on it it would rev up and flatline. I set the boost for 15psi. full boost was about 12.4AFR on the one tune, and 11.2s on my tune. Could the problem be PE?

We tested the FPR, i boosted it up to 10, and the fuel press rose the same. Tried a different memcal, and that didnt affect it. My backup ECM must have internal damage, cause it wouldnt even run the truck. ...and the brake caliper falling off completed the night.
 
JSM

JSM

Active member
Re: Engine flatlines/jumps

Aeroking said:
Well found the knock problem. All 8 bolts on holding the caliper backplate to the rearend housing came loose, and the passenger side came apart. Luckily under Pats skilled expertise, we were able to nurse it back to his garage and replace the bolts.

On a side note, i learned a couple things. If i leave the truck in a certain gear, and slowly roll into the throttle, it'll wind up good. But it seems like as soon as i hit WOT it hesitates. Running on Pats tune it hesitated about 5500. When i put mine back in for the ride home, i noticed i could progressively give it throttle and it revved good, but if i stomped on it it would rev up and flatline. I set the boost for 15psi. full boost was about 12.4AFR on the one tune, and 11.2s on my tune. Could the problem be PE?

We tested the FPR, i boosted it up to 10, and the fuel press rose the same. Tried a different memcal, and that didnt affect it. My backup ECM must have internal damage, cause it wouldnt even run the truck. ...and the brake caliper falling off completed the night.
Click to expand...

You mean Pauls tune?

5500 might have been his fuel cutoff, how far do you want to spin the motor?
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

TwinTurboV8Ty said:
You mean Pauls tune?

5500 might have been his fuel cutoff, how far do you want to spin the motor?
Click to expand...

no i was on Pat's bin. Still havent tried Pauls bin :oops:. The trans should shift around 5600, so i want to at least rev to that.

IIRC the "Hi RPM Breakpoint" for the timing was the point in which the "Adv Timing" slope took over correct? I see other people's are set to 5000. I set mine to 4800, so the advanced slope can pickup right where the F1 leaves off. Am i misunderstanding the breakpoint value?
 
qbnkiller

qbnkiller

Conflaguration Specialist
Re: Engine flatlines/jumps

If what you try doesnt really help it out, I'd like you to try something:

Put your tune back in. Take it to around the RPM where it flutters like that. Add 10% more fuel in the affected cells (forget what the AFR's say) and see if it helps move the flat spot.

Just a hunch....
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

Did some test/tuning yesterday. and came up with some decent results.

First of all, a light bulb appeared over my head when i was looking through datalogs. Seeing that i did all my testing from 60-100mph. Basic Math > Me shows that 3.42 gears + 1:1 trans ratio @ 100mph = .....4500rpms. Instead of stopping at 100mph, i took it up to 130ish, and the truck went past 4500rpms. :tup:

Also noticed that my truck chokes with low timing. It knocks alot at 15deg. But at 25deg it runs nice and clean. The lowest i could turn it down to was 20deg. Below that it would knock. All tuning was at 20psi, and i turned the meth off for easier tuning.

Next thing to play with is the boost solenoid in TP.
 
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