[unruhjonny]

Beware!!
There are two versions of the 'Doug Roe' book;
the first one is 296 pages, and was first published in 1973;
It's a larger book than the one pictured on that amazon link.

I bought that book ages ago, then found the original/more in depth version - and sold my copy of that book at a swap meet last year.

First version:



Second version:

[Kenth]

Here are the correct specs for 1970 RA Q-jets

[Kenth]

Here are the correct specs for 1970 400 Q-jets.

[Kenth]

Here are the correct specs for 1968-69 RA Q-jets.

[unruhjonny]

You made me go and double check;

I did find a typo in my last post that I am embarrassed (if that's the correct word) to now see.

Here's what I should have double checked to confirm as being correct:

Originally Posted by unruhjonny

jets / primary rods / secondary rod

7040270 = 70 / 38 / CC
7040273 = 70 / 38 / CC
7040263 = 70 / 41 / CC

7028270 = 72 / 41 / BE
7028273 = 72 / 42 / BE
7029270 = 69 / 38 / BP
7029273 = 69 / 36 / BP

If I am seeing correct, your first post shows 270/273 should have a 39 primary metering rod.

Your pages have a November 1971 print date, while my 1970 book has a December 1969 print date.
(My 1969 Rochester book has a January 1969 print date.)

I cross referenced both of these with my latest printed master parts catalogue (December 1975 print date);
It does indeed show #70 jets and #39 rods for '0270/'0273 - so there must have been a TSB issued that changed the metering rod from a #38 to a #39 - neat!

[padgett]

Bigger jet and smaller rod is richer.

[Kenth]

Originally Posted by jhein

Yesterday I got my new carb. It looks good. It's going to replace my current carb which is a likely fake 7040273 Frankenstein carb. I can't wait to get it on the car.

Looks "refabricated".
Wrong vent tube, lack of triangular washer on vent tube, wrong located pump rod, incorrectly adjusted pri to sec axle rod, wrong screws for air valves etc..
I would certainly take a closer look on every part on this Q-jet for authenticity.

And, it´s seldom, if ever, a good idea to move jetting from one carb to another without checking the whole recipe and all bleeds, restrictions etc. involved for calibration.

FWIW

[jhein]

Originally Posted by Kenth

Looks "refabricated".
Wrong vent tube, lack of triangular washer on vent tube, wrong located pump rod, incorrectly adjusted pri to sec axle rod, wrong screws for air valves etc..
I would certainly take a closer look on every part on this Q-jet for authenticity.

And, it´s seldom, if ever, a good idea to move jetting from one carb to another without checking the whole recipe and all bleeds, restrictions etc. involved for calibration.

FWIW

Yes, it's not all original. But then, It wasn't represented as that, it's a rebuilt (probably multiple times) carb and it has some other parts on it. The seller describes it as "restored" rather than "rebuilt". I'm not sure exactly what they're tryin to convey there. Technically, restored should mean all original in the purest sense. Maybe restored from a function and finish standpoint? Whatever. I think it looks good and as long as it performs as it should, I'll be happy.

The one thing that bothers me the most though is the accelerator pump rod. I even eventually noticed that myself. It's fixed easy enough but if they got that basic thing wrong then what else?? You could say it was just a simple error. But, do you really want a carb built by someone who makes simple errors? So hopefully there aren't more.

Like I said, I'm going to put it on and run it and see what happens.

[burd]

Why would they cad and not do the rite green.

[SD455DJ]

Originally Posted by unruhjonny

You made me go and double check;

I did find a typo in my last post that I am embarrassed (if that's the correct word) to now see.

Here's what I should have double checked to confirm as being correct:



If I am seeing correct, your first post shows 270/273 should have a 39 primary metering rod.

Your pages have a November 1971 print date, while my 1970 book has a December 1969 print date.
(My 1969 Rochester book has a January 1969 print date.)

I cross referenced both of these with my latest printed master parts catalogue (December 1975 print date);
It does indeed show #70 jets and #39 rods for '0270/'0273 - so there must have been a TSB issued that changed the metering rod from a #38 to a #39 - neat!

Glad to see that the 70 / 39/ CC is correct for the '70 RA Q-jets. I'll have to swap out the wrong metering if it's too lean after I drive it a while and check the plugs. Thanks to Kenth for posting the p/n's for the carbs!

Dennis