i found something new on edelbrocks web site what do you think?
<TABLE cellSpacing=0 cellPadding=0 width="100%" border=0><TBODY><TR bgColor=#f2f2f2><TD class=spc2>Victor FE EFI (for Square-Bore Carbs)</TD><TD class=spc2 align=right>#29365</TD></TR></TBODY></TABLE>
http://www.edelbrock.com/automotive_...d_bb_vic.shtml
shoudl i do it? or should i machine my performer rpm to do the job?

 

Interesting. Haven't seen that one before. I've seen the Victor intake, but not the Victor EFI. If you've got the money to spend, it should eliminate a lot of hassle. Figure up how much it would cost to modify your intake, considering materials, machine shop charges, and your time. It may just be worth it.

Edit: I didn't see any description of what exactly they do to them so they're "EFI". I would assume they place injector bungs in the ports. I'd definately call for specifics before ordering.

 

the ijector holes are machined into the runners... as well as the hold down for the fuel rails

 

hey rusty you have the fuel injected 390 dont you? can you email me youremail address in case i have any questions ? im trying to build one myself for my 79 f150 and any input would be appreciated
my addy is rjonese(nospam)@shaw.ca

 

http://www.edelbrock.com/automotive_new/misc/company/pdf/06_108-123(efi).pdf
here is the catalogue pdf ... its near the bottom if you want a better picture

 

That IS quite cool...

Too bad I don't have anything to put an FE in anymore

Someday.

 

I like how the website says "for square bore carbs". Smart. Don't know what your engine plans are, but the victor is a RACE intake manifold. EFI will make carb intakes work where they shouldn't, but efficiency is lost. If you're turning under 6500 the RPM gets my vote.

 

agreed this is a high rpm manifold HOWEVER.. Because the fuel injector is located over the intake valve, there is no chance for the low rpm bog associated with single plane intakes... when the valve opens the fuel shoudl be sucked right in

 

Intake reversion still occurs fuel injection or not. You're mostly correct though, the fuel is mostly taken out of intake manifold selection equation, but air isn't. Longer, smaller runners increase gas speed and are still better for low end torque, fuel flowing through them or not. The RPM has a pretty healthy sized plenum volume for a dual plane. If you want cool looks go victor, if you want gas mileage with almost the same power go RPM.

Also, it's difficult to tell from edelbrocks pictures how the injector is aimed, but I seriously doubt they can aim the injector at the backside of the valve on a single plane intake. And they probably don't care either because it's a race intake that's built for peak HP, not idling in traffic.

 

the type of manifold doesnt matter for fuel efficiancy if its efi....Its regulated by the tune of the ECU. I have never seen a shred of proof to say that a dual plane will work better and produce more tourqe in this situation than a single plane, not saying there not out there.....

 

You should let the auto manufacturers know this. They've been wasting all thier time and energy developing perfectly sized plenums and tuned runner lengths for nothing! The fuel efficiency of an engine is not regulated by the ECU. The ECU is programmed to supply the fuel the engine needs over it's operating area. If you just program in an injector PW for an RPM and load because that's what you want the engine to run with things won't work out for you very well. An engine's volumetric efficiency is how much useful power the engine makes for a given volume of air. The ECU has absolutely no control over how effiently the engine burns the proper air/fuel mixture it's the engine's internal configuration and airflow characteristics that make it efficient running in the narrow operating range of RPM and load the engine will spend most of it's life in. The short fat runners of a single plane intake manifold do not generate the high intake air velocities that induce combustion swirl at low engine speeds like dual plane intakes with longer, skinnier runners.

The reason why you don't see this proof is because most carb'd engines converted to port injection are built with the intention of higher rpm use and racing. Not daily driven street efficiency. Also, dual plane intakes are not converted by most shops because they are more difficult. I convert them and they work extremely well. I cannot say I've done a side by side comparison of big dual plane to a victor manifold on an engine, but can say that the FE RPM is plenty capable of big power and good economy with port injection.

 

I agree with all the points made and i understand the fundementals of why dual plane would be better(infact i called edelbrock and holley and explained this point of veiw to them .. First the guy at edelbrock told me it just would not work well for my application which agrees with our beliefs that longer (preferably straight) intake runners work well with low rpm's
The holley rep told me that by using a dual plane intake would in effect starve the motor for air( i tried to get him to explain his reasoning but he was not very knowledgable. he seems to be spouting junk that he was told to say) he then tld me that a TOO large intake would have no bearing on my motor and drivability would not be affected.

Now this is what i believe.... i believe that too large of intake would prolly be ok although it would prolly result in a small amount of reduced performance. And dual plane intakes are not good for these applications for only one reason. Its usually too hard to place injectors at the correct angle to get proper spray patterns behind the intake valve.

i think that the reps for these companies just do not seem to understand what it is I want and are refusing to commit to any systems that they are not sure (that is not tested in their labs) if they will work.

this being said im gonna stick with my performer intake and a carb..... i dont want to spend 800 bux on an intake and 1500 on fuel injection and have problems... besides i can always add it later and sell the carb and intake right?

 

It comes down to runner length. Open plenum, short runners. Dual plane, longer runners are possible for SOME of the ports.

 

The difference here is how the intake is set up.

Dual plane intakes set up a resonance in the manifold. This helps low end torque. The divided plenum hurts high end power.

Single plane intakes do not develop the resonance, and therefore have less low end torque. The open plenum helps it develop more high end power.

Larger ports can be used with EFI that would otherwise let the fuel drop out of suspension.

 

Actually, dual plane runners are considerably longer. The shortest FE RPM runner is 7 1/4" and the longest is 8" to the plenum. That's not equal, but pretty darn close. I don't have an FE Victor at the moment, but maybe someone who does could chime in with the measurements. On an FE, the injectors must be placed a little further from the intake valve than other engines. To facilitate spraying at the valve the injectors must be angled atleast 15 degrees. Most single plane FE intakes are too tall to allow this angle to be achieved. Also, spraying on the intake valve does not help with higher RPM horsepower so it's not a concern of most shops. It does help atomize fuel at cruising speeds though (efficiency).

You can quite easily assemble a complete dual plane FE port injection system for around $1500 total. There's alot of hype to EFI. Alot of the time, the high-buck race part is the "recommended" part when in reality it's not necessary or even will it give the best results. Using a few OEM parts here and there and letting go of the idea that sequential injection is a must-have or your engine will be a failure can save you thousands. Batch and bank injection work great, the cheapest megasquirt ECU will do everything you could need and more, dual plane intakes defy the scientists at edelbrock and holley and will actually flow enough air to feed most street engines.

Or keep tweakin' that holley.