Virgin 17059553

[Pav8427]

I was brought back into Quads when I bought my 79 H/O in 2013. The car had sat for 10 years so a rebuild was in order. I rebuilt it back to stock with help from 'the book'. At the time all emissions stuff was still in place. Since then I have bypassed all that. No EGR. No Cat. Only hooked dist. to ported vacuum and recurved.
I always wondered what a carb with some mods would do for me. Not really a high HP thing, but would it improve anything?  Since then I have bought a virgin 17059553( mixture screw caps still in place) and although it is used, it hasnt been abused.
Prior to ordering a kit, I am at a point where mods would need to be done. Again original was rebuilt completely stock with no mods. Kind of thinkin of my own novice back to back carb test. Using basic tests and 'da butt dyno'. Just to see if I can make anything better. Gotta go to work right now. But will post all carb dimensions soon.
What do you think. Will mods do anything for me?
Thank you. Doug

[Pav8427]

Here is what I have;

Idle tube. .032
Idle down channel.  .043
Upper idle air bleed.  .067 main body
Lower idle air bleed.  .067
Idle bypass.  N/A
Idle mixture screw holes.  .073
Main air bleeds.  .067 airhorn
Main air bleeds.  .028-.032(.028 is loose. .032 no-go)main body
Secondary POE restrictions.  .052
Secondary tube restrictions.  .033
Secondary POE well restriction.  .040
Air flap open distance.  1.385ish.
Jets.  .074
Primary rods.  52m
Secondary rods.  CV w/E hanger.

The two carbs are only 72 days apart with one having a BZH plant code and the other a BZN.
As of last fall. Timing is at. 12* initial. 22* with VA. 36* @ 3000ish.
At the time I put it to bed for the winter. That seemed to be the best so far on the old butt dyno.
Also wondering if notching secondary air flap will help or hinder?
Could I build this to the 'generic' example in the book(page 94) or the first 'recipe'?
Possibly low end of that? Or

Any suggestions would be greatly appreciated.
Thanks. Doug

[Cliff Ruggles]

Doug, when you get time call the shop and I'll get what you need for it headed your way.  It woln't need much, minor recalibration and some good rebuild parts.  Those carbs are quite a bit leaner than the 48 State carbs.....Cliff

[Pav8427]

Will do. Probably be Next week. Pretty busy for a few days.
Thanks. Doug

[Cliff Ruggles]

I'm more than just busy, BURIED in phone calls and emails. 

With the zombie apocalypse going on everyone is home and working on their old cars.  The phone has been ringing non-stop for over a week!.....

[Pav8427]

I git the kit and parts we talked about. Everything is as it should be. Thank you. Would it be best to stick with factory float setting for this?  Could I bump it up a bit? Would that help anything? 
Thanks. Doug.
PS. Good luck with the ZOMBIES. I have plenty of venison if the meat dept. becomes bare.

[Cliff Ruggles]

Stock float setting was really low in those going from memory.  I typically set them high unless it's going on a completely stock original application (quite rare these days).

It's pretty quiet in these parts, hardly seeing anyone out and very few cars on the roads.....no Zombies yet, but the plague is starting to hit Ohio pretty hard....

[Pav8427]

Sounds good. I will try .280ish. They just called for shelter in place here in Minnesota. Starts Friday and midnight till the 10th. Cases are going up pretty fast.
Take care all. Be safe.

[Cliff Ruggles]

Unless it has an original high pressure fuel pump set-up I use 9/32" so you should be good there.

I use a similar 17057274 carb on my engine and have been using it close to 30 years now.  It's never grumbled once in all that time with 7.5psi fuel pressure from a 140gph electric pump and regulator with a return system and that's with one of our .145" high flow N/S assemblies and small float........Cliff

https://www.youtube.com/watch?v=6zVdoLR-VzM

[Frank400]

Funny cause I'm currently working on a virgin, still sealed 17080253 (307 Oldsmobile) and it has 75 main jet with 54M primary metering rods.  I was convinced those M rods (.036" power tip) were only found on Chevy single main air bleed carbs, and I thought mine had been replaced at one point, but it seems like they came in those Olds carbs. 

[Cliff Ruggles]

Frank, I've only seen them in CA emissions Olds carbs to date (pretty sure they started using them around 1977) but obviously they may have also used them in the last non CCC Olds units in 1980.  Hopefully you are getting one of our rebuild kits for your 1980 unit.  Since the Zombie Apocalypse started I've been BURIED in orders for kits and parts and made sure I was well stocked up before this all started fearing we wouldn't be able to get parts for quite some time if things got out of control.......Cliff