Hey Godffery & traveller, thanks for the input.
This is certainly not the 1st time I have dealt with stacks. Both my Lotus TC's (both dry sump, 1 street, 1 race), the solo1 2TG, and my MGB & Spitfire all had them. Even have this link still in my Favourites -
http://www.velocity-of-sound.com/velocity_of_sound/calculator2.htm if I really want to 'get it right'.
An engine is nothing more than an air pump. Given this is a stock motor, with no head work, there is a limit to how much you can cram through. I'm actually concerned that the Swarbrick pipes flow to well, and will have to add baffles not for sound, but to gain backpressure.
The plan from the beginning was to create a strong / clean running stock street engine. The only mod will be a slotted cam sprocket, so I can play with the cam timing.
I've read a lot of the threads about pods vs air box, and other 550 carb issues. Two things stick out to me. When you remove the air box, and just install pods, you also loose the 'stacks' that connect them to the box. This can be only detrimental to intake air velocity at low throttle opening. I am not convinced yet that the box's 'still air' is an issue though. So adding stacks has to be the 1st step in re-balancing the system. As to long or short, for a street engine mid range & torque are king. So tuning for that is the primary goal, and I can get there by different paths. The 50mm are about what I would like to use, but shorter can work as well, would just choke it down slightly (the 33 ID x 30mm). This is what Hansen appears to be doing with those racing stacks. I know this works, because I used this trick on my racing kart where we were restricted to stock parts, but any filter.
The other issue seems to be the timing advance. Having rebuilt distributors for MGs & Jags I think I'm going to play with that as well. The standard trick has been to shorten the spring. With the MG ones, you can not only use different springs (x3 spring rates available), but also different weights. This allows you to tailor the advance curve. Trying to figure out if I can adapt my Sun 504 Tester to the Honda setup.
Thanks for the lead on the booties Joe. However I need a 'street' solution, and they don't offer full protection. As I mentioned before, I also want to have an 'air gap' between the filter back, and the bell mouth. To my mind if the 'filter' (bootie or screen) is sitting on the bell mouth it has to be disturbing the air flow, and there by limiting the effectiveness of the stack. Both Piper & ITG recommend a minimum of 20mm clearance when using their filter socks with stacks.
Boy this got long!
Quick comment on CR29's. It seems to me that for the $800US what your really getting is stacks, & more importantly accelerator pumps. Those little beauties can hide flats spots in a wink. If I can't get the PD's working to my satisfaction, I'm going to try 750 carbs, because of the pumps.