EFI straight eight Buick

[GH]

Doug, lookin good. Does the return fuel line from the pressure regulator go all the way to the tank at the rear? Who makes those screw in injecters? Mike and myself are waiting on the cam and he had heart trouble and I had knee surgury, but both doing good, will get back to work on the Buick shortly. You are going to love the efi and datalogging.

[Buickguy3]

    GH,
Don't rush getting well, either of you. The car can wait a little while. Yes. the return line runs all of the way back to the tank. Actually there are two of them. They are the two lines [feed/return] that we used with the carb. [one is not used]. We ran a new #10 feed line for the new system. Injectors arent screw-in, just clamp-down like the Bosch ones. We fab'ed the feed fittings and the bungs from Aero-quip 90 degree els #10x#6, and #10x#6 bushings.

[Stan Back]

I think I've figured out how you get the valve cover off . . .

[Buickguy3]

      Three pieces!    [This pic is before we found out we had to take off both ends]

[GH]

Doug, has the snow melted off the test track yet?

[Janderson]

Do you have a shot down the Int. port or is that top secret?   

[Buickguy3]

GH,
Test track is dry, but had a software glitch[ain't technology great?]. Had to send the CPU back to Electro-motive. Will be on the road when they get it back to us.
JAnderson,
There are two posts previously that get as close to the shot that you asked for as I have. The top of the manifold was tacked on before I got there with the camera to get a shot. The runners are about 6" long and tapered from about 2 1/2 wide at the top to 1 3/4 at the base. They are, as you can see in the last post, flared at the top. The domed ends just happen to be the bases of two 57 nailhead oil filter cans [hey, in Montana you have to use what's handy].

[Janderson]

I meant a picture down the Int. port of the head.
    That previous post of the Int. manifold correct?  I am wondering what you did at the "brick wall" where the port splits to the valve bowls.  I have been playing around with putting a vane in this area to try and help the air make the turn, or even splitting the siamesed port into 2 ports with a separator.  I suppose with boost pressure you aren't as concerned with this, but I am working with a NA engine.

[Buickguy3]

JAnderson,
Sorry, I misunderstood. We used a full sequential system, that the Electro-motive TecIIIr system allows as an option. By doing that, each cylinder gets to use the whole port, and doesn't neccessitate splitting the port. It works great. On the old twin turbo street car, Frank used the older Tech II design and on that one, he had to put a splitter vane on the manifold that went in and was profiled to seperate the port into two halves. That meant that each cyl. saw only a little tiny 1/2 size port. Worked, but not very efficient. That system was very cumbersome and is over 10 years old now. I'm afraid you could try porting to regain some area, but you'd probably strike water. You are right, boost does offer an advantage. Doug

[Buickguy3]

GH
How's the healing process going for you and Mike? Any pics yet of the new EFI on the Buick? I meant to ask before, how many inches is the GMC, and what kind of compression can you run on those?
Doug

[GH]

Stan, look at the post just a couple of posts previous. GH

[Rex Schimmer]

Buick Guy,
Does your EFI system use an O2 sensor? A friend of my that is a flat head nut has installed the threaded bung for a Bosch O2 sensor in each of his header tubes right at the flange and he bought a small hand held "electronic gizmo" that looks at the O2 and give you the A/F ratio. Something like this might be handy when you or out on your "dyno" as it would allow you to look at the A/F for each cylinder.

Just a thought.
Looking forward to seeing you guys at the salt! Neat project!

Rex

[Milwaukee Midget]

I meant a picture down the Int. port of the head.
    That previous post of the Int. manifold correct?  I am wondering what you did at the "brick wall" where the port splits to the valve bowls.  I have been playing around with putting a vane in this area to try and help the air make the turn, or even splitting the siamesed port into 2 ports with a separator.  I suppose with boost pressure you aren't as concerned with this, but I am working with a NA engine.

I'd be cautious about what at first glance seems a logical idea.  I'm going back to David Vizard's book on the A series engines, which deals with the Austin/Mini/Midget engines - they also have siamesed intake ports.  A knife edge at the beak of siamesed ports between the valve bowls can act as an obstruction, and any other division of the port would probably restrict flow, although you might pick up velocity (Tuning the A-Series Engine, 3rd edition, page 195).

Panic has also read this book cover to cover, and probably has a better understanding of the issues than I do.  I'm not sure what you're building, but I know it's not recommended for my engine.

[Buickguy3]

Rex,
Thanks for your post. You are correct that there is a somewhat blunt division where the two bowls come together. The thing that helps this is the two cylinders. don't fire together. That lets one cyl. get all of the airflow for it's intake cycle, and the other cyl. on that port gets it all as it's intake cycle comes around. They don't fire next to each other or at the same time. That is why you need to run a full sequential system. This is just like spark advance in the ignition. Just before the intake valve opens, the injector fires for the next cylinder to go through intake ,then compression, then ignition. You could split the ports, and have a very similar setup, but you then would be restricting each port to a 1/2 size port. Unless you build a new head , you have to live with this setup. [could happen if this doesn't pan out]
Doug

[GH]

Doug, the healing is going good. Mike received the cam from Donnie Johansen yesterday. The guy that is cutting the O ring grooves and installing the O rings is going to do that this weekend, we hope. Still thinking where to put the injecters. The GMC is 311 ci and the comp. ratio is around 8.3 to 1, has flat top blower pistons.