BBC Blown & Injected runs rich on E85

[8mywal8]

Hello I am new to this forum. I am hoping for some good insight on getting tune a little closer, here's what I have,

468 BBC 7.1 compression
Dart 360 heads(flow 400 cfm at .800)
Cam is solid roller .284-.296@.050  .850 lift
671 blower 18% over(going bigger soon) about 9LB boost
Enderle Bird Catcher 
Nozzles are as follows .026 in front ,second row .028 last four are .030(front cylinders seem to run richer do to the helix)
Pump is a Waterman 700 flows 6.9GPM at 4000 RPM(I think it's to big)
Main jet I have been from .120-.167 always stays rich

When I drive e car I can pull fuel on/off halfway and bring my wideband to about 8.2 AFR and motor smoothness out and runs clean. With the lever all the way open I am at 6.8-7.2AFR.
No HS lean out yet

any advise would be greatly appreciated,
Ronnie

[triplenickel]

Welcome 8my. Not sure I can give you any concrete answers as I have not dealt with blown injected setups. Is it mostly the idle that is fat? If so, lean out the barrel valve. Was this a methanol system previously? If you can't take enough fuel away, you may need another bypass. Might want to talk to some of the fuel injection guys, like Crawford, Kinsler, Enderle, etc.

[8mywal8]

Thank You,
No it was a gas set up but was never finished and I have been in EFI word. It is basically rich all around. Doesn't seem to lean out to much anywhere according to my wideband. I have tried many different main jets and the bigger I go doesn't seem to lean it out. I started with .033 nozzles and went down from there but from what I understand nozzles pretty much set the operating pressure. What I need to see is how people plumb the hi speed. Not really sure where this poppet goes. Actually pictures of plumbing period to see if I have this correct. I got my schematic off Good Vibrations.

thanks,
Ronnie

[triplenickel]

Which of the 3 diagrams did you follow? How does it perform at full throttle? Your idle will have to be rich to cover the hole because of the absense of an accelerator pump.

[8mywal8]

I believe I am on the right track. I was putting smaller nozzles in and was then having to adjust my barrel valve to much. Yesterday I put my .033 back in and adjusted the barrel valve until my idle AFR was back at about 8.1. Checked the barrel valve with leak down and I was at about 25%. Seems to run much better. From what I have been reading I should need around .036-.038 nozzles. I think that is correct. Adjusting full throttle is not a problem, I can do that with a high speed. I would like to get the part throttle to lean out to about 8.3 AFR so the engine will smoothen out why driving. Any Ideas? Am I on the right track?



Thanks,

Ronnie

[triplenickel]

Double check pop off pressure of main jet poppet. May be a little too high causing higher idle pressure. If your barrel valve has an idle bypass port, you should be able to bleed off a little fuel at idle & slight throttle opening.

[8mywal8]

Where is the idle bypass port located?
Pop off was set to 2LB. But I will check again tonight. Slight throttle opening is really what I am looking for.

Thanks

[triplenickel]

It's on the barrel valve. should be marked. If you refer to the Good Vibrations diagrams, it shows the location on the different type of barrel valves. I think it also shows pressure ranges. You can double check the port with air. Air should come out at idle & start diminishing as the throttle is opened. It should shut off well before full throttle.

[triplenickel]

I referred back to them & the port is marked out. Are you plumbed like the gas set up or the alky setup? Is your jet in the check or in the barrel valve?

[8mywal8]

My main jet is in the TEE on the inlet. It is plumbed like gas. Seems less adjustable this way to me. I have a blank behind the front 9/16 plug. I was told this secondary poppet was for after a burn out to relieve extra fuel pressure on quick throttle shut off. Should I plumb it like alcohol? Then I would have a high speed lean if needed.

Thanks for your input,
Ronnie

[triplenickel]

Either way. If you want to add a high speed, you can add another tee in the main line. The secondary check valve does relieve pressure when the throttle is closed after a burn out or at the end of a run. With it setup like it is, put air to where fuel goes into barrel valve. Check to see if air comes from the out port all the time or if it stops when the throttle is wide open.
Do you street drive & race this car, race only or street only? Are you trying to lean it out for street driving?

[8mywal8]

Yes for short street cruises. I will race it primary but love bee bopping around town. I'm not looking for fuel mileage at all. But you can here it sputtering when it's in the low 7s afr. In the low 8's it's smooth.. I am going to try putting air to it and see. Thanks I will get back to you.

Ronnie

[triplenickel]

No problem Ronnie.
A suggestion would be to add the secondary check valve to the out port as diagram shows with a small jet & set at a pressure that will allow it to open at idle or just above. You can set up a shutoff valve on it to turn it off when you race it & turn it on when street driving. You can use a manual shutoff valve or they also make electrically operated ones. I've also seen a valve that is manually adjustable to flow how much you want. You may be able to use something like that. Close it when racing & open it a predetermined amount when street driving.

[8mywal8]

I thought about an electric lean out valve hooked to a toggle switch I could click on when cruising.

All great ideas. So simple yet so complex

[triplenickel]

Yep, that's cars for ya!