Thanks Ron,
Yeah satisfying to get the result I was looking for. That was the reason I tried the TQ again to try and keep the AFR where it wants to be for as long as possible. Interesting how you can instantly feel the engine pick up under accel as soon as the AFR gets into the sweet range on the gauge.

Ray

RayR, sorry, I'm a little late to this thread, but I've got a handy little tuning spreadsheet I put together some time ago to help me with the tunning efforts.

It's a Lotus 1-2-3 spreadsheet (alright, alright...you done laughing yet? LOL), but Excel should have no problems pulling it in.

Anyways, the 'Comparison' tab does a all-at-once check, while the 'RodJetMatrix_A/B/C' tabs do the specifics. Each one defines a BASELINE setting of jets and rods, then calculates the % surface area change for available fuel...so this actualy gives you the real difference the carb sees as opposed to a straight forward jet/rod diameter changes. It does this calculation for the primary, secondary and TOTAL areas. Than given the mix of my tuning components it lays out the Lean=>Rich roadmap.

Re: air bleed sizing, etc, etc...I've done a whole bunch of experimentation with these, great carbs to tune, but yeah, not having any spare parts and tunning (jets, rods, etc) is a real impediment.

In addition to the great stuff in this thread check out the following posts:

1) thread_1

2) thread_2

3) Dippy.org thread

there is one thing about tuning thermoquads that most dont seem to know. the primary side of the carb should be tuned by the metering rods in my opinion.i know that they are hard to find. but here is my tip: use edelbrock avs rods bent and cut to thermoquad length on the big end. they are available from edelbrock. i could be wrong but there is no need to play with the air bleeds in the carb top portion.

Good info, which ones?

many, many years ago, i wrote CNC programs for primary and secondary jets, and metering rods. i made several for my use, and kept the programs. unfortunately, those were written when CNC's were using tape programs. shows how long ago that was ! programs are useless for machines now in use......

Thanks Diplomat, some great information here in the other threads, I had found the first one before but not the others. The spreadsheet sounds great, unfortunately I couldn't get Excel to recognize it - any chance you can save as an Excel and re-post?

Although I think my configuration is close to "correct" per the AFR numbers I am still going to try some more options to see if my seat of the pants gauge shows any improvements!

Re the comments on Edelbrock rods, I made a couple from these rods BUT a couple of issues, they do not have the small 'cruise' center portion and the taper is too steep.
I used the cheap method to modify. Start with a rod that is a little larger than the sizes you are aiming for (or if you are lucky exactly right) put in the new bend then mounted an electric drill in a vise, clamped the rod in the drill and then VERY carefully use miniature files to ""turn"" down the rod at a slow/medium drill speed and finish off with emery cloth. Bit fiddly but works if you are careful!!

Ray

OK, here it is...I did not have a chance to open this up in Excel, I used Apache OpenOffice though and it come up fine.

I applaud you guys, but reading through all this just makes me all the happier I converted to fuel injection.

LOL, you know, I'm an IS guy by profession...so FI is normally "my thing"...but so is working with the "elements" Cave-Man style...ha ha...ahh...the joy of overcoming the air/fuel obstacles!!!

Amen brother, I respect you being able to rub 2 sticks together and make fire.
My carb always stumbled and never ran right, just glad they started making "lighters" that are affordable, my car has never run better.

I love this stuff...

I've been a TQ fan for years, but never had one run really well until I found a NOS 9000=series (GM linkage) at a swap meet. That carb runs great - or did on the 340 in my Valiant. With a square-to-spread adapter on my 68 440, it was never as crisp as the AVS it replaced. I'm hoping that I can solve that with a proper spread-bore manifold for the engine I'm putting in now. Seemed like a mechanical issue more than anything, the HP 440 was certainly more capable of pulling air than the 340, and it just didn't seem like the secondaries were working right.

So I've got a bit more time to spend with my TQ and really appreciate all the hard work you guys have put in over the years.

Thanks Diplomat, opens fine now. Looks like a good resource for future tweaks.

Also agree with the FI guys, If I was doing a major rebuild I would also strongly consider it but for now happy with the TQ and has been fun (most of the time) getting the old tech to work well and stay largely original.

If we didn't have a desire to keep the old tech running this would be a pretty empty chat line!!! Can't imagine changing the 440 for an electric motor!!

RayR