2056 setup, Carbs, High Elevation Options

[grantjd]

Car setup:
74 2.0
Stock 2.0 heads
2056 w/ EMW jugs and KB pistons
Weber 40's

I'm looking to set up my 2056 for street use in the 5500'-9000' elevation range. I live just outside Denver, and this car will see primarily mountain canyon roads and street driving at a minimum of 5500' elevation.

The highest octane fuel we have commonly available out here is 91. I do not want to have to seek out anything higher.

I currently have EMW's G cam.
Advertised:
EMW G 287 x .430
Web 86 273 x .423
Web 86a 290 x .435

I bought this car with the dual carbs. Im not opposed to trying to piece together a stock FI system, but I already have everything for the carb setup.

Comments on the G cam vs an alternative?

Looking to set C/R @ 8.5:1 for use with the 91 octane, comments?

Thanks!

[Mark Henry]

It's not just as easy as looking at a chart, the only "easy" way is with a wideband meter.
With a 4000' range difference you will still have issues on carbs, they'll still be farting and on a cold day icing when you go to the top of the hill.

I don't think the #86 will run stock FI, but you could use an SDS or MS EFI ECU and the stock intake.
I've done this with SDS and earlier this year there was an excellent install thread with a very stealthy MS ECU in the stock FI can mod. These plenum system work well at altitude, good vacuum for the MAP sensor which IIRC through reading vacuum corrects for altitude.
The Web #86 is also close to a scat C25 cam, good vacuum, should work well with above. I ran this combo with the SDS, ran as smooth as factory d-jet. For a couple years I drove without the programmer connected, totally reliable.
YMMV and I must add I don't have huge swings in altitude here.

[JamesM]

It's not just as easy as looking at a chart, the only "easy" way is with a wideband meter.
With a 4000' range difference you will still have issues on carbs, they'll still be farting and on a cold day icing when you go to the top of the hill.

I don't think the #86 will run stock FI, but you could use an SDS or MS EFI ECU and the stock intake.
I've done this with SDS and earlier this year there was an excellent install thread with a very stealthy MS ECU in the stock FI can mod. These plenum system work well at altitude, good vacuum for the MAP sensor which IIRC through reading vacuum corrects for altitude.
The Web #86 is also close to a scat C25 cam, good vacuum, should work well with above. I ran this combo with the SDS, ran as smooth as factory d-jet. For a couple years I drove without the programmer connected, totally reliable.
YMMV and I must add I don't have huge swings in altitude here.

(IMG:style_emoticons/default/agree.gif)
When we had the RRC meets in Colorado there was always at least one carbed 2056 that I would wind up passing with my wimpy injected 1.7 on the climbs due to the carbs struggling. any other conditions the 2056s would leave me in the dust, but with big elevation changes, FI is king!

Need to add though that with MS for "real time" elevation correction you need to add a 2nd MAP sensor. With a single MAP sensor MS will correct for altitude but only based on the MAP reading BEFORE the engine is started, so stopping and starting again will correct for the new altitude which works for most, but if you are doing 5000ft climbs in a single drive you will want a 2nd sensor.