Did I forget to put on deodorant?
Carb Linkage trouble (Dual Quad)
Hey fellas just got around to putting the induction system together on my Starliner. Upon doing so I came to the conclusion that in fact I had lost the instructions to the factory type linkage that I had received. The persons assisting me with this assembly do have dual quad experience, but not of this type. The linkage is from Carls Ford Parts, and the carbs (465cfm Holley vac secs) are from Price Motorsport Engineering (PME). These carbs are mounted backwards and have the 427 type bell crank assembly that opens the front primary slightly ahead of the rear, we’re good on the secondary operation. PME was nice enough to send me copies of the manual that shows proper adjustment and setting (Haynes? Chilton? Ford?) We have looked at pictures and have assembled the linkage, but are not sure we have it right adjustment wise. We would like it to operate as it was intended. Can anyone give some pointers or tell me which manual has this information (that would be great) so I can purchase it? Thank you in advance for your time.
1 - 20 of 20 Posts
Actually it's your breath.....J/K But looking for a response to your question is kinda like looking for that elusive snipe. Linkage is subjective and it seems no two setups work the same. You are asking for a manual on something that did not exist from the factory, so no real manual exists. Mulitple carb linkage on applications such as yours is nothing more than trial and error. The closest anyone can come to what you request is in Galaxie and Fairlane shop manuals that show factory 2 x 4 linkage on 427FEs. Will that work for you? I dunno. I suppose it will if the carbs are configured the same as the FE setup [backwards and uses a bell crank between the carbs with the exact linkage and throttle piviot points of each carbs.] But there lies the difference between your carbs and carbs designed for 2 x 4 application. The 427FE carbs have 2 different piviot points on the carb throttle lever as one is the primary carb, meaning any linkage movement will move that throttle first and as throttle movement continues will activate the second carb only after a given amout of primary throttle movement has been acomplished but the piviot points are configured to make both carbs reach WOT at the same time. [different opening ratio] Thats why the factory linkage has a slot to allow one carb's throttle to move without affecting the secondary carb until about, say 30deg of primary throttle movement. Clear as mud, right?Did I forget to put on deodorant?
What does the throttle arm look like on your carbs? The arms for the stock linkage are different than most. Couple pics for ya........
I also have adjustment instructions somewhere on my puter. If I can find them, I will post them up.
I also have adjustment instructions somewhere on my puter. If I can find them, I will post them up.
Attachments
-
38.8 KB Views: 129 -
41.8 KB Views: 96 -
59.4 KB Views: 117
you got assembled , just check for the pri shafts can close , delayed second carb pri. opening and both pri. are open at wot . if so your good to go .Hey fellas just got around to putting the induction system together on my Starliner. Upon doing so I came to the conclusion that in fact I had lost the instructions to the factory type linkage that I had received. The persons assisting me with this assembly do have dual quad experience, but not of this type. The linkage is from Carls Ford Parts, and the carbs (465cfm Holley vac secs) are from Price Motorsport Engineering (PME). These carbs are mounted backwards and have the 427 type bell crank assembly that opens the front primary slightly ahead of the rear, we’re good on the secondary operation. PME was nice enough to send me copies of the manual that shows proper adjustment and setting (Haynes? Chilton? Ford?) We have looked at pictures and have assembled the linkage, but are not sure we have it right adjustment wise. We would like it to operate as it was intended. Can anyone give some pointers or tell me which manual has this information (that would be great) so I can purchase it? Thank you in advance for your time.
Thank you all! this is the ticket! I will have to view the arms when I get back to the shop. The are stock I believe. Fordman59, where did you get those pages from! That is what I was looking for. Was it the one RJP was talking about? And yes RJP, I did forget to brush! It wont happen again!
Don't remember where I got them. Someone put them up on the net from a shop manual. I snagged them for my own use. My 1850-2s are modified with the throttle arms like you see in the shop manual. Had to drill a different hole for the back or secondary carb (as in one of the pics).
Fordman59, How much cam and motor are you using? I ask because I have to do the power valve change which requires the measuring of engine vacuum at Idle and then dividing by two (according to Holley). Now that would be ok if I had a single quad on first and it was running well. I then would take the measurement and do the power valve math. The problem is this engine is starting life as a dual quad. How can I get it to run right enough to measure the vacuum if it wont idle or run correctly due to the modifications required in the first place? (did you follow me?) Could I just ask Comp Cams what this cam produces for vacuum at idle, divide that number, and start from there?
Not sure how Bill Price sets them up. Can ya tell us what jets, power valve and carb size to start? Maybe your engine build too? Cam, compression, cubic inches all determine idle vacuum. A tech at Comp should know about what vac it will make at idle.
Do as you would for one carb with the power valve selection. At first, be more concerned with the correct idle fuel restrictions in each carb. If your idle mixture screws work well when they are around 1-1/2 turns out, no adjustments needed to them. Then go to the main jets on your tuning schedual. If the carbs are std stuff, they will need to be leaned out some.
Do as you would for one carb with the power valve selection. At first, be more concerned with the correct idle fuel restrictions in each carb. If your idle mixture screws work well when they are around 1-1/2 turns out, no adjustments needed to them. Then go to the main jets on your tuning schedual. If the carbs are std stuff, they will need to be leaned out some.
Yes they are stock except for the vacumm secondry link kit. The engine is a 466, with Comp X4262H cam, compression is about 9:9:1. I did'nt know you knew Bill Price, He is a very nice man, he helped me a bunch.
Gal60...ask and ye shall receive....as you saw the above. But one thing that everyone has failed to mention is that 2 x 4 carbs are not calibrated exactly the same as a single 4 carb. There is some minor differences in IFRs and IAB between the two. A carb that is calibrated for 2 x 4 use is usually slightly leaner than a single 4 bbl and has a slightly larger IAB than for a single carb. This is to say that your 2 450s may not be dead nuts on in the idle/low speed circuit as a matched pair of carbs that were intended for use as a real 2 x 4 set up. If you run into a over rich condition this is the first place I'd look.
I do a bunch of 2x4 FEs. The general instructions you're seen here are correct. You want to adjust the linkage for WOT and make certain both carbs can cleanly return to idle. Make certain that there is no binding through the travel against the fuel lines or linkage itself.
The two carbs do need to have different pivot mountings for the linkage - the rearmounted carb being closer to the throttle shaft centerline. The carbs at 450-465 cfm are going to be really small for the engine - I would choose at least 600s for a 460+ incher. Maybe 750s. You do not size 2x4s the same as single fours.
The two carbs do need to have different pivot mountings for the linkage - the rearmounted carb being closer to the throttle shaft centerline. The carbs at 450-465 cfm are going to be really small for the engine - I would choose at least 600s for a 460+ incher. Maybe 750s. You do not size 2x4s the same as single fours.
Thank you all for the information. When I was purchasing the carbs I figured that the combination at wide open throdle would in fact be a little too much for my set-up. I almost went with dual 390 Holley's. Oh well, i'm stuck with these now. Could have had the 600's for alot less. It's funny that before I bought these things, everyone was telling me that the 465's were just right (I could'nt afford the 550 cfm BJ BK replicas). Now that I have them, I am being told that they are too small. I just can't win. Is there a part number for the pivot mount? Thank you all again.
Not sure of a # for the pivot mount. Check these out (about half way down the page). http://www.gessford.com/cobraparts/fmisc.htm
Thank you Fordman59, I will look into those. While we are on that subject, I think I sold Bill Price short on that product description. He in fact installs the trunions on the carbs for the linkage as well as the other modifications mentioned. Sorry Mr. Price!
I thought he might have had some things done to them. I don't think he is the type to sell stuff that doesn't work. But, I have not bought any of his parts. Just word of mouth.
Hope ya give us an update when ya get her running.
Hope ya give us an update when ya get her running.
Will do brother!
Thank you I am putting my 1965 galaxie R code back together, This is great info.More for ya.
Don't worry about the power valves just yet. Idle vac divided by 2 is only a place to begin tuning, not the answer. When you do progressive "bottom-up" tuning from idle, then transition, then lean cruise, lean high-cruise (primary main jets), and finally power AFRs at throttle above that... then you are tuning the PV rating and PVCRs for enrichment when you need it. It's the last thing on the primary tuning list and fuels ±80% throttle to WOT range.I have to do the power valve change which requires the measuring of engine vacuum at Idle and then dividing by two ...
You need to build the foundation of tuning to that point. Once you're there, you'll know the vacuum it pulls at high-cruise, and can set the PV to come in right above that for smooth transition from cruise economy to max power.
Yes, one tune can get it all.1 - 20 of 20 Posts
460 Ford Forum
A forum community dedicated to Ford big block owners and enthusiasts. Come join the discussion about performance, modifications, horsepower, tuning, build specifications, and more!
Full Forum Listing
Top Contributors this Month
View All
The Mad Porter
60 Replies
the_partman
33 Replies
PSIG
24 Replies
