CIS fuel distributor info
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Racer
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I just had my fuel head checked and rebuilt for I believe the first time in 20 years. While it was being checked and rebuilt I asked some questions. What difference does the system pressure make in more or less fuel as long as your in spec.? NONE. Will you keep getting more fuel if you max out the fuel pin? No, at the last 1-2mm of travel you won't get anymore fuel. Does the euro head give you more fuel than the US one (silver)? YES, I know most people already know this. What is the flow spec. of the fuel to the lines? Well, mine balanced out at 117cc but this could vary a little from one head to another. Even if one port can go higher you need to have them matched so the numbers might have to come down. I had one that would go to 120cc.
So there you have it, you might be wondering after all these years if your fuel head is distributing and even fuel to each injector? For that matter if each injector is flowing the same. You won't know unless you send this stuff out to be checked and matched. Then the manifold needs to be flow checked too for even air. Then you can say you should have an even A/F at each cylinder. The pains of CIS
Brent
So there you have it, you might be wondering after all these years if your fuel head is distributing and even fuel to each injector? For that matter if each injector is flowing the same. You won't know unless you send this stuff out to be checked and matched. Then the manifold needs to be flow checked too for even air. Then you can say you should have an even A/F at each cylinder. The pains of CIS
Brent
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Brent, did your guy say how much better the euro head was? I know you said you got 17% more flow after the mod, is that now beyond the euro's baseline? Is the mods performed on your US head possible on the euro too, so that whatever the euro can flow can in fact be improved upon to a similar degree? Just wondering- enjoy your posts.
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Ken,
I have the euro head and yes I got 17% more than the stock spec. or baseline as you called it. If you do this and have the Lee Rice fueler you will be pig rich in the low to mid range. BUT, I should be ready to start modifiying stock WUR's to work like the Andial units on boost intead of vacuum. I can even convert a stock WUR like Lee does. Will know later this month if I plan on doing this and how much it will cost.
Brent
I have the euro head and yes I got 17% more than the stock spec. or baseline as you called it. If you do this and have the Lee Rice fueler you will be pig rich in the low to mid range. BUT, I should be ready to start modifiying stock WUR's to work like the Andial units on boost intead of vacuum. I can even convert a stock WUR like Lee does. Will know later this month if I plan on doing this and how much it will cost.
Brent
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Brent,
I posted on your other post. I looked into this sometime ago also. I wanted to know how to get more fuel and to control it. I found that the internals modified by EDM'ing the slots bigger to allow more fuel to be supplied. The exact mod, I have no idea of what and how though. But as we are discussing, getting more fuel is only one part. getting it when you want it is the other part.
I posted on your other post. I looked into this sometime ago also. I wanted to know how to get more fuel and to control it. I found that the internals modified by EDM'ing the slots bigger to allow more fuel to be supplied. The exact mod, I have no idea of what and how though. But as we are discussing, getting more fuel is only one part. getting it when you want it is the other part.
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Brent -
The guys who did the work on your fuel head - are they in the Dallas area? That looks like a local area code.
Also, you said they improved your Euro head beyond it's stock spec - can they modify a US head to match a modified Euro head - or are the two just too different?
Looking fwd to news of your WUR mods - but I noticed one thing. You wrote that you would be able to match the "Andial" unit for enrichment on boost vs. vacuum. I thought that was the problem with the Andial - no enrichment at vacuum, i.e., initial throttle "tip in" and the reason Rice's unit is preferred - it supposedly has much improved initial throttle response. I must be missing something - FI tuning is a little beyond my expertise....
Thx
Mitch
The guys who did the work on your fuel head - are they in the Dallas area? That looks like a local area code.
Also, you said they improved your Euro head beyond it's stock spec - can they modify a US head to match a modified Euro head - or are the two just too different?
Looking fwd to news of your WUR mods - but I noticed one thing. You wrote that you would be able to match the "Andial" unit for enrichment on boost vs. vacuum. I thought that was the problem with the Andial - no enrichment at vacuum, i.e., initial throttle "tip in" and the reason Rice's unit is preferred - it supposedly has much improved initial throttle response. I must be missing something - FI tuning is a little beyond my expertise....
Thx
Mitch
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The main guy is from TX but the guy who does the rebuilds is from LA.
I don't know for sure if he can get more fuel from the US head but I think it's possible.
I was just making a comparison to the Andial fueler where I made my stock WUR enrich more.
Since I now have more fuel than stock from the fuel head I don't need the extra enrichment anymore. This is obvious from my dyno chart. That is the whole reason I changed the WUR. Now when I dyno the car again to check the fuel curve I can see where I'm still too rich and use a mechanical boost controller (one way valve) in line with the WUR to delay enrichment if needed. Still once again I might go electronic to control the fuel pressure thus the fuel curve but I want to play with this first.
I don't know for sure if he can get more fuel from the US head but I think it's possible.
I was just making a comparison to the Andial fueler where I made my stock WUR enrich more.
Since I now have more fuel than stock from the fuel head I don't need the extra enrichment anymore. This is obvious from my dyno chart. That is the whole reason I changed the WUR. Now when I dyno the car again to check the fuel curve I can see where I'm still too rich and use a mechanical boost controller (one way valve) in line with the WUR to delay enrichment if needed. Still once again I might go electronic to control the fuel pressure thus the fuel curve but I want to play with this first.