Final words and pictures

It has been some time now since I finished the install. The L88 cold air hood is painted and functional. The ECU is programmed. Maybe I should start off with some pictures...

I will discuss some problems I have found and what I did to solve them below, but first a picture of the cold air induction:

Ok, so what problems have I had with this setup over the last year and a half?

Fuel pump failure

After about 10 months the Holley fuel pump supplied in the EFI kit started making some very disturbing noises. It definetely gets your attention when the pump starts making a loud, grinding noise! Holley sent me a new pump under warranty and were nice enough to send the newer Wal-Bro style pump they now supply. This pump has much better capacity and is used in some OEM applications (which will hopefully mean many trouble-free miles). I'm happy to report that this pump (as was the first pump) is very quiet. It is not audible with the engine running, even with my quiet exhaust.

HEI module failures

The 81-86 style large cap HEI started burning modules at a rate of one every 2-3 weeks. This has also been the experience of a fellow Corvette big-block EFI converter, so I do not think there was anything wrong with my specific distributor. Theory is the large cap HEI overheats in the cramped Corvette engine compartment, especially with a big-block. The solution was to switch to the 87-95 small cap HEI that uses a remote coil. I swapped the distributor 7 months ago and sofar it is working great.

Incorrectly cast intake ports

I don't know what Holley was thinking when they designed the intake for the oval port big-blocks, but the ports were tiny. I took the intake back off and dug the ports out with an air grinder. Have a look at the picture and note the finished port on the right compared to the untouched one on the left. The area is increased by over 25%.

Burnt plug wires

This one isn't strictly EFI related, but the fualty plug wires made me chase ghosts in the EFI programming tables, trying to get rid of mysterious misses. I tried various versions of accell wires and have now concluded that they are junk. Even with boot protectors cylinder 3 and 5 would start arcing through the boot to the header tube after 2 weeks. Solution was to switch to Borg Warner Select spiral core OEM replacement wires. Application is a 1995 Chevy 454 truck. The length of the wires is perfect, the terminals correct for the small cap HEI and after 6 months they have still not arced. 

Insufficient injector size

After hanging out at a EFI related forum I found out that the Holley injector sizing guidelines are not correct. 30 lbs/hr injectors are not large enough to safely run a 500 hp 454. I found a set of Ford 42lbs/hr injectors on Ebay, and later sold my 30's for the same amount that I paid for the 42's. The Ford 42's (from the Lightning truck) swap right in and are high impedance like the 30's they replaced.

So how does it run?

Very well, thank you. It takes a long time to get all the settings in the ECU perfect, but once they're right the engine really does run nicely. This is a true driver that has to get me to work every day. I can now get in the car in the morning, turn the kay and it starts right up. It goes to a smooth 1000 rpm idle. I put it in gear and drive off. No bucking, jerking or anything. As it warms up it goes down to a 800 rpm idle. Doesn't matter if ambient temperatures are 30 degrees or 110. The ECU compensates and feeds the engine the correct mixture. I'm running closed loop all the way down to idle and have no problems. It really is like a different car compared to the carburetor, and in my opinion definetely worth the expense. Mileage is up 10%-15%. 

And finally some more pictures: