Recommendation: Which Distributor for 2.8L V6 (84)

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Which Distributor for 2.8L V6 (1984)?

I have a 1984 Firebird with 2.8L V6. It has an ECM which controls carb mixture and distributor ignition advance. After 200k mi - the original carb is tired and the emissions equipment has simply gotten too tempermental to hold a tune. I have a replacement VaraJet that I'll be rebuilding out of an S10 which is a bit simpler than the original.

In addition to installing the carb (and removing the check engine bulb) I believe I'll need to replace the entire distributor with a vacuum advance version.

If so any recommendations on which distributor I should go for?

A distributor from a mid 1980s S10 with 2.8L also has vacuum advance - should I go with one of those?

The car/engine is stock, dependably gets 25mpg currently - just want good overall driveability and gas mileage.

thanks.

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Just noticed that in 84 some S10 V6 2.8Ls came w/ and some w/o vac advance. What's up with that? Will my Firebird work OK with the orig ECM hooked up to the distributor (check engine light will go off when the TPS and Mixture Solenoids are disconnected forcing an open or closed loop mode I'm guessing).

Should I find an '84 S10 Distributor WITH vac advance?

[jwvess00]

Hi there!

Federal emissions 2.8V6 carb. truck engines (S-10, S-10 Blazer) have mechanical/vacuum advance distributors. 2.8V6 carb. California emissions truck engines have computer-controlled distributors and computer-controlled carburetors. All 2.8V6 carb. cars 1981+ have computer-controlled distributors.

If you're ditching the computer controls, you'll need a vacuum-advance distributor. If you're keeping the computer, you need to get a distributor without a vacuum advance.

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Thanks.

Yes - thanks for confirming my suspicions about the vacuum advance.

I'm looking at replacing the original computer controlled Vara-Jet E2SE for an S10 type Vara-Jet 2SE carb due to mileage/age issues w/ the original carb (200k mi). That means I'll be loosing the TPS input to the ECM...

...And in turn, losing the TPS to the ECM forces the need to convert to a vacuum/centrifugal advance replacement distributor.

I'm not looking to specifically ditch the computer controls... - but w/o TPS... well, they become casualties in some or most cases.

Follow-up question: Without TPS input to the ECM - how did the early S10s with carb 2.8L V6 control their 700R4 TCC lockup? I have an F-Body and am pretty ignorant on the differences with respect to the S10 version of the 2.8L V6 drivetrain.

thanks

[jwvess00]

Hi there!

My S-10 came with the carb. and distributor you're after. They're not any better than the E2SE, honestly. I think they ended up on my wife's '85 Celebrity (a dozen years ago, or more) when its ECM freaked out. I converted my truck to TBI in the summer of '95 and haven't looked back.

You're right in that all you need is the carb. and distributor -- everything else (including details like air cleaner, throttle linkage, etc.) stays the same.

There is a module between the ECM and the CEL called a "lamp driver module" that was only used on the carb'd cars with ECMs. You can remove that module and the lamp won't light. Follow the dash harness from the ECM and you'll find it. If memory serves, it's a plastic box that inside has a card that plugs in. Just pull the card out. That may be easier than disassembling the dash to remove the bulb.

On my Blazer, GM used a vacuum switch to unlock the converter under load. I still have that switch laying around, as well as a good bit of its wiring harness. Let me know if you want it. I got rid of all of the other carb. stuff (for the truck and the Blazer) a while back.