Big Block performance upgrades and fuel injection

[ccdually]

What have you guys done to your big blocks and any recommendations on an aftermarket fuel injection set up would be awesome. Lets see some pics.

[LTZ C20]

There are so many different options these days it is ridiculous. With that being said, you may want to check out Howell Engine Developments. I bought a TBI kit from them, uses all factory type wiring colors, connections and parts. Comes with instructions, diagnostic manuals and much more. Really great for the price. Can be integrated with air conditioning, transmission controls, speed sensors. I used their big block TBI kit to fit the needs of my modified small block however, they have TBI, MPFI, TPI and LS options. I haven't had any issues and I've been using it for at least a year now. System works great. The TBI kit is OBD I so it is outdated but, still reliable and easy to work on. They have more modern options obviously, just depends on how high tech you want to get and how much lettuce you want to feed the bunny rabbit. I'm very pleased with my outdated system. Truck has great power and torque and is the most reliable it has ever been, far past what it was with a carburetor.

[SomeTexan]

What have you guys done to your big blocks and any recommendations on an aftermarket fuel injection set up would be awesome. Lets see some pics.

I would say to find a Vortec 8.1L take out. It's a decent engine to build from and the efi is pretty good and very tuneable, it uses the same computer as the LSx engines. If you didn't want the engine, it still gets you a computer, harness, sensors and everything else for efi. If you want to go aftermarket, Holley Dominator EFI is my favorite. Great customer service, super tuneable, more inputs and outputs than you will ever need, and it can control late model transmissions.

As for tbi, I can't really help you. I would take a carb over tbi any day.

[ccdually]

My truck currently has the factory TBI in it. I want to go aftermarket aluminum heads and a good cam for torque. Making sure that its tuneable and can handle the power upgrades is crucial.

[SomeTexan]

My truck currently has the factory TBI in it. I want to go aftermarket aluminum heads and a good cam for torque. Making sure that its tuneable and can handle the power upgrades is crucial.

What are your power goals? I guess it's going in your dually?

Personally I would just look for an 8.1 pull out. It's not hard to modify the harness, it's a factory stroker with decent parts, and (at least around here) you can find them cheap. $1500-3000 with trans and all accessories. That's your aluminum heads and efi for the cost of one. The downside is to tune the factory computer you would need EFILive or HP tuners, and they aren't cheap. You could always find a local shop that will tune for you though. I had an 01 2500HD 8.1 with a procharger making just under 650whp, just the procharger, a cam, headers and a set of injectors.

[lyndoncp]

I'm currently running FAST EZ EFI on my sbc and love it. I ordered the complete kit and it had everything you need to get up and running. Its great for plug and play and super simple to install and program. The "classic" EZ EFI controls fuel only. If I had to do it again I would go with the FAST EZ 2.0 so I could have spark control as well as fuel control, its super nice to play with the spark curve with different A/F mixtures for fine tuning. Some of the limitations of the FAST set ups are the amount of power you are feeding and how radical of a cam you are running.

I made some mistakes and took the "long way" in a couple areas working out gremlins. If you do go with FAST classic, let me know and I can tell you about a couple things to do (or not to do) to get your system tuned nicely, quicker.

[Funkatation]

I have the Fitech on my 489. It works well and the price was right. Have the fuel command center as well.

[ccdually]

If I could get to around 650lbs and 450hp I'd be super happy. It is for my dually. I'm going to trade part of a paint job to a buddy of mine for a complete 8.1 with and Allison. Any performance tips on the 8.1 would greatly appreciated.

[SomeTexan]

You would be close with a stock 8.1 with headers and a good tune. A cam would really be all you need, or some head work. Get some good head work done, mill them to up the compression a little, a low end cam, then a good tune done on the dyno (not a generic mail order tune) and you will have a towing machine. I believe stock injectors will support it at that level, but aftermarket injectors can be had for under $300 a set. They use the same stuff as the Vortec LS engines. Use LS7 lifters, they perform well and aren't very expensive. ARP rod bolts are a good upgrade although shouldn't be needed where you want to be.

[ccdually]

Any pics available? How about opinions on the Allison Tranny?

[big_al273]

The Allison 1000 5 or 6 speed is one of the best automatic transmissions ever put into a pickup, however you will either need to do a body lift or modify the transmission tunnel to make it fit. You would also need to find out about the electronic controls with either an aftermarket TCM (Transmission control module) or modifying a Factory TCM and harness.

[LTZ C20]

Allison transmissions are EXCELLENT units. If you get the Allison and the 8.1 together out of the same truck, everything will already be set up to work together and you will only have to supplement or strip the harness for parts that are vehicle specific. The harness can be adjusted and the ecm/tcm reprogrammed to be standalone engine/trans control only with no other inputs or outputs that the donor truck would have needed but your truck won't.

[ccdually]

Perfect! I have and matched set. Will likely modify the firewall since my truck is lowered.

[SomeTexan]

Any pics available? How about opinions on the Allison Tranny?

I don't have any pics. The builds I did with 8.1's were sold years back. I might have pics on film somewhere, but nothing digital. I haven't messed with them since I discovered the LS engines. Since the LS came out, everything else is obsolete. The only way I deal with big blocks any more is if they are tall deck with aftermarket bore spacing. The cons outweigh the pros until you are over 700 cubic inches.

I ran an Allison behind an 8.1 in my 01 2500HD, it had zero problems. For towing it was great, but it's a little slow shifting for performance. Personally I like the 4L80e better for performance. In my 71 K5 I ran a 4L80e behind an 8.1 with good results.

[LTZ C20]

Perfect! I have and matched set. Will likely modify the firewall since my truck is lowered.

Then it's much easier. Just have to strip the harness of its unneeded wires and reprogram the ecm/tcm. Or you could send them both out to companies that do this for you. Depends on how much you want to spend and how inclined you are skill and equipment wise to take on these projects. Personally I would do it all myself.