L31 Extreme Budget Build

[Supercharged111]

What VE map? The timing map is 4 like 5 values. Idle advance, advance start rpm, total advance, rpm for total advance thing how many degrees of vacuum advance. The fuel map pre-loads with the startup wizard based off the displacement, injector size and cam duration/idle vacuum.

It doesn't have a VE map? How does it calculate fuel needs?

 

[L31MaxExpress]

The alternator is apparantly bum though if anyone caught 12.2 volts. Double checked the wiring to it and it is not charging at idle, only slightly increases at ~2,500 rpm.

 

[L31MaxExpress]

It doesn't have a VE map? How does it calculate fuel needs?

Well I am sure it has a VE map, probably a pulsewidth map, but it is not user accessible. The ECM self learns off the wideband. The long term is how much it has adapted off the base map.

 

[L31MaxExpress]

To speed the learning process up, shortly after it fired, I looked at the fuel adaptive and it was showing a short term of -20%, I pulled 15% out of the idle area manually. Then set the base timing. At that point sounded a lot better. Then I held it at about 2,000 rpm and saw the adaptives removing about 15% at cruise, so I pulled 10% out. The manual change helps how quickly it learns.

 

[Supercharged111]

Well I am sure it has a VE map, probably a pulsewidth map, but it is not user accessible. The ECM self learns off the wideband. The long term is how much it has adapted off the base map.

Weird. Especially when you've cut your teeth tuning legitimately. One of these TBI systems is tempting for the plow truck. Bigger cam, an intake that doesn't choke at 4500, it'd feel like a boosted small block and still knock down semi-acceptable fuel economy. Is there a lean cruise option?

 

[L31MaxExpress]

Weird. Especially when you've cut your teeth tuning legitimately. One of these TBI systems is tempting for the plow truck. Bigger cam, an intake that doesn't choke at 4500, it'd feel like a boosted small block and still knock down semi-acceptable fuel economy. Is there a lean cruise option?

I actually just kind of want something that I can throw it on and ignore to be honest. I actually bought the system more for the manifold, fuel rails, and throttle body, bought the whole thing new for $1200. Then decided to just toss it on and see what it would do. Then again I did leave a 24x reluctor behind the timing cover and a knock sensor in each block drain.

15:1 is the leanest it will command.

This is true sequential port fuel, not TBI. It uses a dual synch distributor to know when to fire the injectors.

This one came with the 29 lb/hr injectors. I choose the 43.5 psi regulator rather than the 58 psi on. Edelbrock says it is good for 400 hp at 43.5 psi at 85% duty cycle and 450 hp @ 58 psi at 85% duty cycle. I assume those values may even be a bit conservative on an engine with a decent B.S.F.C considering I have seen 24s make 450+ numerous times in LT1s, but they at a bit more ducty cycle.

 

[Spareparts]

Man i wish i could figure out tuning.
I have HPTuners and anything more than turning on/off fans at a set temp and turning off vats is just beyond me how to do it!

 

[L31MaxExpress]

Man i wish i could figure out tuning.
I have HPTuners and anything more than turning on/off fans at a set temp and turning off vats is just beyond me how to do it!

The learning curve is quite steep. Look at some Youtube videos from HP Academy and Goat Rope Garage. 20 years ago basically had to teach myseld reading stuff from Grump, RBob and Taxion on Thirdgen and the old DIY-EFI group.

 

[L31MaxExpress]

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[Scooterwrench]

Sounds good man!
So how far over "budget" are you now?