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FBO VAcuum Adavance Distributor?
#1153837
01/10/12 08:28 AM
01/10/12 08:28 AM
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Indiana
YO7_A66
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Is anyone running the FBO vacuum advance distributor? The quality looks to be good.
Who is the original manufacturer of the unit?
The magnetic pickup electrical connector appears to have been replaced with the Chrysler style electrical connector, which tells me that the original manufacturer might be one of the bigger named brands. The magnetic pickup has a .026" gap which might not be a MP unit but maybe a MSD unit.
Thanks
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: lewtot184]
#1153840
01/10/12 10:03 AM
01/10/12 10:03 AM
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YO7_A66
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I would be running it with my new MSD Street Fire ignition box that might not care about the .026" gap.
Since it ran on a dist machine, I would like to try it but I am a little concerned about this gap.
Does the MP dist come with the electrical connector replaced like this one? I don't recall my last MP unit having the two heat shrink tubes like this one. It just looks like the connector has been spliced in.
Thanks for your reply.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: lewtot184]
#1153842
01/10/12 11:04 AM
01/10/12 11:04 AM
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YO7_A66
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I have emailed him three times over a 2 week span with no answer.
Sorry about the quality of the pictures and thanks for your reply.
There is no way that .026" gap would have worked with my FBO or my MP ECU, but I will find out what gap MSD spec's for the Street Fire box.
Last edited by YO7_A66; 01/10/12 12:01 PM.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153843
01/10/12 12:37 PM
01/10/12 12:37 PM
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NORTHERN VA
THESHAKERPROJECT
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Quote:
I have emailed him three times over a 2 week span with no answer.
Sorry about the quality of the pictures and thanks for your reply.
There is no way that .026" gap would have worked with my FBO or my MP ECU, but I will find out what gap MSD spec's for the Street Fire box.
..........................Are you shure about that ? I run the same dist from FBO with the FBO ecu and it runs fine , actuall way better than the stock MP one. The FBO dist LOOKS like a MP/mallery unit but side by side there are a few differences in the castings that few will notice. I just put it in the car and set the total timing that was on the FBO spec sheet and it runs perfect. The vac advance never pulls the dist out of phase like my stock MP one. If you think the gap is off just re-gap it. 
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Re: FBO VAcuum Adavance Distributor?
[Re: THESHAKERPROJECT]
#1153845
01/10/12 01:15 PM
01/10/12 01:15 PM
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YO7_A66
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""Are you shure about that?""
I was running the first gen FBO box (ballast) and it would start with no problem with .008" gap. Then I bought the second gen box (12v, no ballast) and D had me move the gap down to .004" and that box still would not light the motor. He took that box back for rebuild. That dist is still set at .004" and the Street Fire starts excellent.
I might reset the gap to .008 then unless MSD says something else.
Thanks to both of you.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153846
01/10/12 01:42 PM
01/10/12 01:42 PM
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YO7_A66
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""I just put it in the car and set the total timing that was on the FBO spec sheet and it runs perfect.""
I didn't get any instructions with the unit but what I do know is:
18 deg initial
12 deg at 12" vacuum timing
16 deg at 2800rpms
Total should be 18+16=34
I am assuming that with the vacuum advance disconnected, I set the initial to 18 degrees at my idle rpm. Then once I hook up the vacuum advance to manifold vacuum, this should add about 12 more degrees and my idle rpms will go up as soon as I plug in the manifold vacuum. Then I was planning on just lowering the idle rpms back down and rechecking the timing at idle.
Is this correct?
I believe that the most important part is that I have at least 10" of vacuum in D with the brake applied. Is this correct?
Thanks
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: lewtot184]
#1153848
01/10/12 09:54 PM
01/10/12 09:54 PM
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YO7_A66
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MSD replied that the .026" gap should not be a problem, but I am going to keep it down around .008" to where I have always run it.
Thanks again for the replies.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153851
01/11/12 10:12 AM
01/11/12 10:12 AM
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Berlin, N.J.
abodyjoe
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Quote:
""I just put it in the car and set the total timing that was on the FBO spec sheet and it runs perfect.""
I didn't get any instructions with the unit but what I do know is:
18 deg initial
12 deg at 12" vacuum timing
16 deg at 2800rpms
Total should be 18+16=34
I am assuming that with the vacuum advance disconnected, I set the initial to 18 degrees at my idle rpm. Then once I hook up the vacuum advance to manifold vacuum, this should add about 12 more degrees and my idle rpms will go up as soon as I plug in the manifold vacuum. Then I was planning on just lowering the idle rpms back down and rechecking the timing at idle.
Is this correct?
sounds right..
initial timing 18* then you plug the advance in and you'll end up with 30* at idle and cruising.. so yes lower you idle.
then when you have full throttle and the vac drops out you'll be full mechanical. 18* initial + 16* mechanical will give ya the 34* total for full out runs.
did you get this set up for your combo? or did you buy it used?
mine is set up a little different. mine is 14 initial, 18 vac, and 20 mechanical.. but i have a basically stock 74 360 in my car.. it runs nice in my car..
It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt. www.MoparMisfits.com
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Re: FBO VAcuum Adavance Distributor?
[Re: abodyjoe]
#1153852
01/11/12 10:21 AM
01/11/12 10:21 AM
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YO7_A66
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"" did you get this set up for your combo? or did you buy it used?""
I called FBO to buy a new distributor and I requested at least 24 degrees initial to keep my vacuum up. FBO explained that they "usually" try 18 initial and then bring in an addition 12 with the manifold vacuum on their SB setups. I like this setup better than my current 24 initial for hot startup reasons. The new distributor will crank with 18 degrees instead of my existing 24, then as soon as the engine starts it will kick in the extra 12 for idle. I can't wait to run it this spring with 30 degrees of timing at idle.
Thanks for the reply.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153853
02/27/12 08:43 AM
02/27/12 08:43 AM
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YO7_A66
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I finally got around to installing this distributor and with it hooked up to manifold vacuum, the idle was rock steady and so was the vacuum reading. I installed it at 18 degrees per the instructions, and I got 14"hg vacuum reading at my normal N idle. Then I plugged in the vacuum line to the manifold source (per FBO's instructions) and then the vacuum jumped up to 16"hg but 200rpms higher than before. Once I readjusted the N idle rpms back down, I ended up gaining one hg of vacuum at the same idle rpms that I had previous to this swap (24 degrees of initial with my previous distributor w/o VA). So now I have 15" hg at my normal N idle rpms (previous 14") and I now show 32 degrees of timing, and I had to back down on the throttle plates around 1/4 turn. I like this manifold vacuum setup because it cranks with 18 degrees of timing, then once the engine is idling the manifold pulls the timing up to 32 degrees at my normal N idle rpms. It did show leaner on my O2 gauge but that will be an easy fix. The FBO distributor is setup with the proper can for manifold vacuum and it appears to work well. 
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: 70Duster440]
#1153855
03/04/12 09:02 AM
03/04/12 09:02 AM
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Berlin, N.J.
abodyjoe
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Quote:
Is it supposed to be actuating the canister at idle? I had him recurve a new MP distributor years ago. Came back with the recommended 18* initial and it does not pull in extra timing at idle. I have 18* initial whether the vacuum canister is connected to manifold vacuum or not. Seems like you'd have the potential for erratic idle if it were.
not sure how he set yours up but he set mine up to actuate the vac canister at idle. i have over 30* of timing at idle. it idles rock steady at 750 rpm..
It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt. www.MoparMisfits.com
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153856
03/04/12 11:24 AM
03/04/12 11:24 AM
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South-Central (Sebring), FL
Commando1
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Quote:
Is anyone running the FBO vacuum advance distributor? The quality looks to be good
FBO's work is excellent.
I talked to Don.
He asked me a gazillion questions.
Custom curved the disributer based on the gazillion questions.
Dropped it in my engine.
PERFECT. Right out of the box.
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Re: FBO VAcuum Adavance Distributor?
[Re: 70Duster440]
#1153857
03/04/12 12:24 PM
03/04/12 12:24 PM
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YO7_A66
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""Is it supposed to be actuating the canister at idle?""
Yes it is. He chooses a low rated vacuum can that will keep the timing steady at idle.
I read allot of articles online before deciding to try the manifold vacuum route.
My previous distributor was a FBO unit and when I bought it from Don about 6-8 years ago, he was all about removing the vacuum can and welding the plates closed. Now he sells these vacuum units that are setup for the manifold vacuum.
He told me that if I installed mine at 18 initial, then my idle would show 30 degrees of timing. I was surprised when I installed mine at 18 and the idle shows 32 degrees. The car starts up great with the 18 initial which will be nice on hot restarts this Summer.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153858
03/04/12 07:24 PM
03/04/12 07:24 PM
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Joined: Jan 2003
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Washington State
70Duster440
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Quote:
""Is it supposed to be actuating the canister at idle?""
Yes it is. He chooses a low rated vacuum can that will keep the timing steady at idle.
It's been awhile. I'll have to check again and see what is or isn't happening. Never had any issues, it always fires right up and idles well - but if I'm missing out on increased performance then I'll want to make adjustments.
I did change one of his advance springs to a lighter one (which I liked) because not reaching full advance until 3400 rpm's seemed late.
I'd be interested to see the instructions he gave. The ones I got were nothing more than spark plug gap and ECU grounding warnings.
He set my dizzy up for 16* initial, 34* total @ 3400 rpm. It was tagged 10* 16" - which I presume to mean 16" of vacuum will pull in another 10* at the canister.
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Re: FBO VAcuum Adavance Distributor?
[Re: 70Duster440]
#1153860
03/05/12 09:55 PM
03/05/12 09:55 PM
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What is the minimum vacuum required per Don?
I was thinking it was 10"hg.
Thanks
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153861
03/05/12 10:20 PM
03/05/12 10:20 PM
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Washington State
70Duster440
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Quote:
What is the minimum vacuum required per Don?
I was thinking it was 10"hg.
Thanks
He didn't say. I'll be talking to him again tomorrow. He thinks I should have more vacuum with the cam I'm running - although everyone else running the same cam reports only 10-12" too. Don's a nice guy but can be a challenge to communicate with.
I could probably stick a allen wrench into the canister and back off the tension on the spring. I'll have to ask Don if that's all he's going to do if I send it to him.
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Re: FBO VAcuum Adavance Distributor?
[Re: 70Duster440]
#1153862
03/05/12 11:22 PM
03/05/12 11:22 PM
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YO7_A66
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I have not tuned mine in D yet, so that is why I am curious. When I told him that I had 11.5hg in D with my last FBO distributor, he didn't seem to think that the vacuum reading was a problem. That is why I was thinking that 10 was the low number. Thank you for the info!!
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: Rick_Ehrenberg]
#1153864
03/06/12 10:24 AM
03/06/12 10:24 AM
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Don changes the can to allow the use of manifold vacuum at idle. I now run this distributor which is connected to manifold vacuum and my N idle is rock steady.
Note: Once I know what the lowest rated vacuum rating is per FBO, then I will tune my in D idle to make sure that I have at least that amount so that my in D rpms (with brake applied) does not fluctuate.
If a distributor has a higher rated can and you try to hook it up to a low manifold vacuum, than I can understand why the idle would wonder. But if the distributor is setup to run manifold vacuum (lower rated can), and you have enough vacuum at idle (or D for an auto), then there should not be any issues with the rpms fluctuating.
I found this description on the net:
""Vacuum advance calibrations are different between stock engines and modified engines, especially if you have a lot of cam and have relatively low manifold vacuum at idle. Most stock vacuum advance cans aren’t fully-deployed until they see about 15” Hg. Manifold vacuum, so those cans don’t work very well on a modified engine; with less than 15” Hg. at a rough idle, the stock can will “dither” in and out in response to the rapidly-changing manifold vacuum, constantly varying the amount of vacuum advance, which creates an unstable idle. Modified engines with more cam that generate less than 15” Hg. of vacuum at idle need a vacuum advance can that’s fully-deployed at least 1”, preferably 2” of vacuum less than idle vacuum level so idle advance is solid and stable; the Echlin #VC-1810 advance can (about $10 at NAPA) provides the same amount of advance as the stock can (15 degrees), but is fully-deployed at only 8” of vacuum, so there is no variation in idle timing even with a stout cam.""
Last edited by YO7_A66; 03/06/12 12:35 PM.
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153865
03/06/12 07:29 PM
03/06/12 07:29 PM
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Washington State
70Duster440
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I decided to swap intake and carb to something a little more street friendly (where, honestly, it spends all it's time) and then re-approach tuning Don's system. He never really volunteers an explanation up front as to his theory behind using manifold vacuum with one of his systems or how it differs from the orthodox use of timed vacuum (which consequently results in a lot of arguments amongst gear heads).
His theory (and I'm not defending it, just restating it) is you take your initial and add a certain amount of vacuum advance at idle to arrive at 30* while the car is idling. That extra timing is added to your mechanical under part throttle/cruise conditions for a more efficient burn of the mixture and drops out when you mash the throttle - where only mechanical is in play.
FWIW, here's a copy and paste from his (copyrighted) tuning guide that goes into more detail:
"We first need to understand that lean mixtures, like at idle and light throttle pressure or low speeds, burn slower than rich mixtures. These lean low load mixtures are a result of lower volumetric efficiency and the scavenge ability of the exhaust port to clear the spent exhaust gases from the combustion chamber this dilutes the oxygen levels and slows down the burn rate. This condition requires the flame front to be ignited earlier in the compression cycle (more advance),allowing more burn time so that peak cylinder pressure is reached at about 12-15* after TDC.
If your engine doesn’t have enough initial timing in it your Exhaust Gas Temperatures (EGT) will rise dramatically due to the excessive fuel that remains unburned in the combustion chamber and tries to complete the process in the exhaust runner and into the headers.
So we’ve determined that a lean mixture burns slower so on the other side of the coin a rich mixture will burn faster. So if you have a rich mixture you need to fire the plug later or retard the timing slightly. Remember we’re trying to achieve maximum cylinder pressure at 12-15* after top dead center, before that point we’re into detonation after that point results in drastic power loss.
The second timing event is what we refer to as “Mechanical Advance”. This part of the advance curve is controlled by Engine RPM only and has nothing to do with load on the engine or cylinder pressure, it’s simply RPM activated through the weights and their retention springs. Sometimes this is referred to as “Centrifugal Advance”. When we add the static or initial timing to the amount of Mechanical timing we get what we refer to as Total Timing.
So if we set the initial at 10* and allow the weights to pull in another 25* of timing we would have a total of 35* of timing at the RPM where the weight travel is maximized or they hit what we refer to as the Advance Limiters.
The third and final timing event and probably the most misunderstood is the “Vacuum Timing”. Vacuum timing has nothing to do with total under load timing or performance tuning. Vacuum timing is controlled by “Manifold Vacuum”, as soon as you accelerate the vacuum in the manifold drops and the Vacuum Timing is released and the timing events are then controlled by the Mechanical and Initial timing settings.
So previously we determined that a lean idle mixture requires more timing to get a complete and efficient burn in the combustion chamber than the under acceleration or full power richer mixtures as delivered by the main circuits.
So to achieve this, the vacuum unit is connected to a “MANIFOLD or CONSTANT” vacuum port and can be set to add anywhere from 5 to 20* more timing in the motor when high vacuum readings or low load conditions are present. So now to calculate the total timing at idle or low load we add together the static or initial, the Vacuum timing and whatever mechanical timing we have based on RPM. Going back to the previous example you would add the 10* initial setting and say 15* of Vacuum timing for a total of 25* at idle or low load, low RPM cruise. Because the vacuum timing is progressive to and directly related to manifold vacuum as the manifold vacuum increases (Light Load) or decreases (As you accelerate) the timing in the motor changes accordingly to keep the efficiency at optimum. The mechanical timing will come and go as engine RPM increases or decreases..."
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Re: FBO VAcuum Adavance Distributor?
[Re: 70Duster440]
#1153866
03/06/12 10:27 PM
03/06/12 10:27 PM
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I tried calling Don today and he was on the other line with an overseas vendor and did not have time to talk. But I emailed him my question on what is the lowest engine vacuum that his distributor is setup for, and he was supposed to respond to me tonight. I am hoping that he will give me a straight up answer (10"hg, 12"hg, etc.) Once I know this answer then I can start tuning my in D mixture. Thank you for adding his tuning response to this thread.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153867
03/07/12 12:36 AM
03/07/12 12:36 AM
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Eugene, Oregon
Secret Chimp
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The above theory makes sense in general but it seems like a lot of weird work to solve a basic problem. Why not just richen your idle mixture properly so you aren't cooking your exhaust? It's a turn of a couple screws. The quote above makes it sound like a lean idle mixture is a given and everybody's been making their headers and manifolds glow like uranium until this idea came along.
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Re: FBO VAcuum Adavance Distributor?
[Re: Secret Chimp]
#1153868
03/07/12 08:53 AM
03/07/12 08:53 AM
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I decided to try the manifold vacuum to see what changes occur in the cruising/idling A/F readings, idle quality (lower idle speed and higher vacuum reading), improved cruising torque, and I like the idea of having a lower initial timing for hot restarts. Having manifold vacuum is like having a start retard setup. During cranking mine will see 18 degrees of timing which will help on hot restarts in the Summer. Then when the engine fires the timing will jump up to 30-32 degrees at idle.
My current idle A/F is richer than most in the 13.5-13.8 range so that when I put the tranny in D with the brake applied, my idle does not go lean. I know that there are members running their idle A/F's into the mid to high 14's ( I assume that these are stick cars) but I can not get mine that lean and keep a good steady idle while in D, well at least not yet. I hope to start driving the car in the next week or two and get my tuning dialed in.
There is more to it than just making the idle richer. There are other benefits that I want to pursue from the manifold vacuum theory especially on my street driven only car.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153869
03/07/12 10:19 AM
03/07/12 10:19 AM
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Phila. Pa.
Mattax
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Rick's advice is basically correct for hot rodded engines. Although many of us bristle at absolute statements like that (and like Don's), for someone publishing to a relatively non-tech audience, its understandable. SecretChimp has asked the right questions. In a situation where exhaust gas is not clearing out of the combustion chamber (typical with both hot rod and race engines) richer than stock settings get a better burn. Additionally, the relationship between AFR and load is not linear. At low load its a bit richer than stoich, then goes leaner - sometimes leaner than stoich somewheres around 60-80% of max load, then richer again to max load. This is for max power and efficiency as shown in the graphs here. A really good and detailed explanation of the choice between ported vs. non-ported advance can be found in this wide-band tuning thread starting at post 10 second paragraph & more in post 13. Also check out 'Shrinker' and 'Sasquatch' posts on the next page of that same thread about the history of ported vs non-ported use by the manufacturers.
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Re: FBO VAcuum Adavance Distributor?
[Re: Mattax]
#1153870
03/07/12 01:15 PM
03/07/12 01:15 PM
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Mattax, Thank you for adding that to the post! I heard from FBO and they suggest that the NEUTRAL minimal vacuum reading is 12" (I am currently seeing 15"hg). Since I have an auto, then I need to keep my in D (foot on the brake) vacuum reading to at least that same 12" mark to keep the vacuum can happy. Thanks again to all.
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Re: FBO VAcuum Adavance Distributor?
[Re: abodyjoe]
#1153871
03/07/12 04:19 PM
03/07/12 04:19 PM
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YO7_A66
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Indiana
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Abody:
""not sure how he set yours up but he set mine up to actuate the vac canister at idle. i have over 30* of timing at idle. it idles rock steady at 750 rpm.""
How much vacuum are you getting at your 750rpms?
Is this in D or is this a 4 speed?
------------------------------------------
Cammando1:
How much vacuum are you getting in N (and in D if you have an auto)?
thanks
Last edited by YO7_A66; 03/07/12 04:25 PM.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: abodyjoe]
#1153873
03/08/12 09:31 AM
03/08/12 09:31 AM
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Joined: Jan 2003
Posts: 5,443
Indiana
YO7_A66
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Thanks Joe,
I am just trying to get a feel for how important the 12"hg target might be. I am going to be real close to that number in D at my current rpm. My previous setup gave me 11.5"hg with 24 degrees initial, so I am hoping that the extra 6-8 degrees at the same rpm will get me over the 12"hg mark.
I hope to get some time this weekend to find out.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153874
03/11/12 03:59 PM
03/11/12 03:59 PM
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Joined: Jan 2003
Posts: 5,443
Indiana
YO7_A66
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I finally got some time to tune the carb today and what I ended up was 32 degrees of timing in N and also 32 in D (foot on the brake). I got 15"hg in N and 12"hg in D. I had to turn up the in D idle rpms just a tad to get the 12"hg but the vacuum and the idle are rock solid. It still likes the A/F in D around 13.5. Once I approach 14.0 in D, the engine just starts to shake allot.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: 71383beep]
#1153876
03/11/12 05:06 PM
03/11/12 05:06 PM
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Joined: Jan 2003
Posts: 5,443
Indiana
YO7_A66
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I was worried too because mine were closed pretty far. It raised the idle rpms by 200 but I was able to lower back down with out any problems.
Just make sure that you can get the min 12"hg in D. I was first showing 11 3/4"hg and the vacuum and idle was still steady. But I didn't feel comfortable with running with less than FBO suggests.
Last edited by YO7_A66; 03/11/12 06:17 PM.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153877
03/13/12 03:47 AM
03/13/12 03:47 AM
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Joined: Jul 2011
Posts: 817
Eugene, Oregon
Secret Chimp
super stock
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super stock
Joined: Jul 2011
Posts: 817
Eugene, Oregon
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So how do you like it after having it for a bit? I've been considering taking the plunge for my wagon rather than monkey with my existing dizzy...
1967 Dodge Coronet Deluxe station wagon
1.03" T-bars, QA1 arms/rods, Cordoba/GM Metric/Volare brake & knuckle, XHDs, Hellwig rear sway, 318 Magnum w/ air gap, 727, 3.23s
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Re: FBO VAcuum Adavance Distributor?
[Re: Secret Chimp]
#1153878
03/13/12 07:32 AM
03/13/12 07:32 AM
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Joined: Jan 2003
Posts: 5,443
Indiana
YO7_A66
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OP
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I have not been able to drive it yet but it should lean out my cruise numbers (currently 30mph to 60mph 14.2-14.6 A/F) without any other carb changes. My decel A/F ratio was dropping down around the 13.0 mark and this should lean back out too.
the only difference so far is that I have gained 1"hg in N and 1/2" in D and the idle and the vacuum is SOLID/STEADY.
Our weather just turned so hopefully I will start to get some time driving it soon.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: Joshs68]
#1153880
03/13/12 09:28 AM
03/13/12 09:28 AM
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Joined: Jan 2003
Posts: 5,443
Indiana
YO7_A66
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OP
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Posts: 5,443
Indiana
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The distributor that I pulled out was a FBO unit with no vac advance that I have run for the last six years. It is now my backup unit.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153881
03/15/12 01:02 PM
03/15/12 01:02 PM
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Joined: Jan 2003
Posts: 5,443
Indiana
YO7_A66
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OP
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Indiana
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I need to clarify something that I stated about the FBO vacuum distributor. I wrote that FBO puts a lower rated can in the dist and this is incorrect.
I asked FBO to tell me what rated can they use and this is their reply:
""There is no "Rating", we install limiters in the vac can to make it do what we want.""
I don't know how they do it, but I like what it does. Sorry for the inaccurate statement that I wrote.
1970 YO7 A66 [Canadian Export] F8 Challenger
340 (Currently in shop for stroker assy.)
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Re: FBO VAcuum Adavance Distributor?
[Re: YO7_A66]
#1153882
03/15/12 03:36 PM
03/15/12 03:36 PM
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Joined: Jan 2005
Posts: 1,647
IL
71383beep
top fuel
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top fuel
Joined: Jan 2005
Posts: 1,647
IL
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i just pulled mine and am gonna send it to him for this as well. I like the idea of additional timing during idle and low throttle.
I have his original ignition setup, his recurved non-VA dizzy, and a 650 Mighty Demon prepped by him and have been very happy with all of them.
Keep up with the posts and let us know how your tuning is going.
'73 GK6 Challenger Rallye - 340 4-Speed
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