Putting A Chip In A TBI Truck

[GreaseDog]

FYI my cam only LS1 made 440RWHP. That's close to 500 at the flywheel. That's LS1 ($3500) + cam swap ($500) = 500HP. Do that with a TBI, I dare you! lol

$3500 for an LS!, what did it include?

 

[4ofakind]

FYI my cam only LS1 made 440RWHP. That's close to 500 at the flywheel. That's LS1 ($3500) + cam swap ($500) = 500HP. Do that with a TBI, I dare you! lol

I can and plan to for half of what you just quoted.

Look guys, I know LSx is all the rage ( and for many good reasons ) but I have already ran all the numbers for multiple situations and a SBC build/rebuild works best for ME. The TBI PCM is the only hurdle left to sort out. Between Third Gen.org, Moates.net, and TBIChips I don't think I'm too far away from getting it sorted.

Mal

 

[Chris]

ignorance is bliss, isn't it? what exactly is it that holds back a Gen I engine's injection system?

The biggest problem is fuel flow. In order to have enough fuel for high HP/RPM engines, you need injectors large enough which will essentially drown the engine at lower speeds unless you're creative with a VAFPR. Tuning is extraordinarily difficult. Mild setups can be tuned to be very drivable, but anything over 300hp is going to need some serious brainpower and forethought put into it. It's simple when you think about it. You're trying to fuel a huge engine with two injectors, and they can only operate at a certain duty cycle before they go static and you have zero control over fueling.

$3500 for an LS!, what did it include?

$3500 is at the high range for an LS swap. A <100K mile pull out 5.3L can be had for $250-$600 depending on where you live. That only leaves the flexplate adapter, engine mounts, headers and tune plus a few odds and ins left to purchase. The wiring is so simple it can be done by a novice. It can be done for a minimum of $1200 but usually around $2K for a complete swap. That's for a stock engine.

 

[GreaseDog]

The biggest problem is fuel flow. In order to have enough fuel for high HP/RPM engines, you need injectors large enough which will essentially drown the engine at lower speeds unless you're creative with a VAFPR. Tuning is extraordinarily difficult. Mild setups can be tuned to be very drivable, but anything over 300hp is going to need some serious brainpower and forethought put into it. It's simple when you think about it. You're trying to fuel a huge engine with two injectors, and they can only operate at a certain duty cycle before they go static and you have zero control over fueling.



$3500 is at the high range for an LS swap. A <100K mile pull out 5.3L can be had for $250-$600 depending on where you live. That only leaves the flexplate adapter, engine mounts, headers and tune plus a few odds and ins left to purchase. The wiring is so simple it can be done by a novice. It can be done for a minimum of $1200 but usually around $2K for a complete swap. That's for a stock engine.

then you up the fuel pressure... my L31 lonblock TBI is running roughly 3x stock fuel pressure, and i have room to go higher.

 

[Chris]

then you up the fuel pressure... my L31 lonblock TBI is running roughly 3x stock fuel pressure, and i have room to go higher.

That still doesn't solve the issue of fuel control. At low rpm, higher fuel pressure is great. (i'm assuming you're talking about the 11psi TBI systems, not the 30psi TBI) Unfortunately at higher rpm there's almost not benefit, since you're ultimately limited to the physical speed at which the injector can open or close. You can tune great for high rpm, or great for low rpm, or "alright" for both. That's the drawback.

 

[woody80z28]

That still doesn't solve the issue of fuel control. At low rpm, higher fuel pressure is great. (i'm assuming you're talking about the 11psi TBI systems, not the 30psi TBI) Unfortunately at higher rpm there's almost not benefit, since you're ultimately limited to the physical speed at which the injector can open or close. You can tune great for high rpm, or great for low rpm, or "alright" for both. That's the drawback.

Ah, in a truck who needs the high RPM? haha That's what cars are for... I don't plan on taking mine past 4500-5000 probably ever.

 

[Chris]

Ah, in a truck who needs the high RPM? haha That's what cars are for... I don't plan on taking mine past 4500-5000 probably ever.

Lol, I could get 6200 out of mine when I played around with the TBI stuff. Totally unnecessary and it made no power, but it could be done. After I put everything back to stock I left the .bin alone sans patching it for lean cruise and correcting for E10 fuel. It runs perfectly and easily returns 450-480 miles to a tank (pretty useful when you burn 2-5 tanks every week). 22+mpg and even 23 if I run light, plus it starts instantly whether it's 108 back home in SC or -8 here in KY. Gotta love it.

 

[1badcj8]

OK... So back on subject

I've read through the whole thread and best I can come up with is that none of these chips do anything for a stock truck. Is that about right? Is there one that will give you a little noticeable power change and a couple MPG's at the same time? Will TB spacer give you any more or less than these (just used as a comparison).

 

[454SSguy]

Pretty much. If you want some tuneability and some MPG's get the EBL from dynamic EFI. It will give you complete tuneability and you'll make some gains in seat of your pants dyno, plus it has lean cruise good for 2-3 mpg for sure. When you start making real upgrades (cam, intake, heads, TBI) you won't have to pay for a new chip. Just retune yourself and you'll get even more improvment out of it. BTW Bob @ dynamic has awesome customer service and will help you through any issues you might have with tuning and what not. It also has a self learn feature for some of the tables so it's even more user friendly. Not that I'm a believer in the EBL or anything LOL.

 

[1badcj8]

Thans SSdude ;-)... Thats pretty much what I was looking for (one way or the other). I really dont plan to push it that far right now as I bought it to be a daily driver. Of course thats why I bought me Jeep back then also...

2-3 mpg seems it could/would pay for itself in fiarly short order...