clwi

Hi all!
Running stock intake on my 468 with Sniper EFI.
My plan is to swap it for a aluminium intake but hood clearance is an issue...Torker will fit but i would like Performer to get more bottom end.
EFI dont like dualplane intakes...but plan is to mill down divider..
Anyone running Performer with stock BB hood?

Fredric Björnefält

Tja Cliwi,

Tyvärr inte, inte vad jag vet,hört eller läst! Har du lämnat svenska corvetteforumet ?

MelWff

translation of above post

Well Cliwi,

Sorry, not what I know, heard or read! Have you left the Swedish Corvette Forum?
Matches to ask if the pink cable on the steering column is for the ignition. Must plug Snipern but it is a bit uncertain where it is going. Have an awesome time!
// Freddan

rcread

I don't know about hood clearance, but the Sniper works fine with a dual plane intake.

Shark Racer

I just switched from a ZZ4 intake to the old Weiand Team G single plane... but haven't driven the car yet. I've done this because of all the internet theories (and my own) around single planes not losing as much power down-low when metering an EFI setup.

I'll let the thread know how it goes if I get some wheel time soon.

68blvert

Curious question. If throttle body efi don't like dual-plane intake why is it that every oem tbi used dual-plane? Like everything else on an engine it's all about the right combo.

Shark Racer

Well, the 80's/90's stuff isn't really an apples-to-apples comparison.

1. Fuel pressures on a GM TBI setup are in the teens, vs 40+ for most modern aftermarket.
2. GM TBI manifolds were designed for GM TBI dual-plane intake manifolds, not aftermarket carbed manfolds.
3. Most of the GM TBI setups are 2 "barrel", with exception to CFI.

There's an Engine Masters video out there that says a specific combo worked better with a dual plane than a single plane.

My hypothesis isn't that TB-EFI "doesn't like dual-planes" it's that the torque loss from a single plane intake won't impact EFI setups as much as it would a carbed setup, since fuel metering doesn't rely on vacuum signal anymore. The tuning dynamics of shorter, larger runners still has an impact(IE shifting powerband to higher RPM range).

The other part of my theory is that at low throttle angles, that fuel has to make many very-sharp turns in a dual-plane setup. Having the fuel come in at high pressures and immediately hooking turns can't be great. Plenum volume and air stability have to be significantly better in a common plenum (single plane) environment where it's a much straighter shot to the cylinders. I don't know a thing about fluid dynamics, though, so I could be completely wrong.

At this point, it's wait-and-see...

clwi

I am still at swedish corvette forum but i get way more answers here!
Dont remember what cable i connected, got some help from a car electrician..

cardo0

Well not to flame you but if you have a dual plane now and you want more bottom end I don't see the performer changing that. So it reads like you expect the Torqer II to have less. Really no way to know until you try it. Something that would be fun to try and compare if you have the resources would be a Torquer II with a 2" spacer. But if you want to shift the power curve you can advance the cam intake center line a bunch - like 10 to 12 degrees should help.
I have read of fuel puddling/distribution problems with EFI on a dual plane sbc. Nothing about big blocks though and the BB may have an entirely different fuel distribution in the manifold compared to a sbc.

Well this doesn't answer your hood fitment question but for that I would look at Edelbrock's w/s as they provide all they're intake height dimensions. So I took a look at Edelbrock's online catalog have it says the Torquer II will fit under stock corvette hood while and the new Performer II requires hood modifications.

Shark Racer

Drive one with the single plane was done last night. The engine nearly stalled coming to the first stop sign - always nerve wracking. ECM figured it out and didn't stall again after.

Car is still learning - lots of stumbling in the 1500-2500 range which eventually sorted itself out.

Results inconclusive - I'd say there is *probably* a loss of torque down low (no surprise) but definitely more raucous up top. The tradeoff point feels like it's around 2500.

With some more driving, I'm sure it'll be a bit better. I'll update the thread after I get some more drive time in.

(I'm struggling to timeshare the car hobby between a 3 year old and a 2 month old - who's starting to scream into the baby monitor right now )

terry82

crossfire injection intakes are single plane.

clwi

my stock cast iron is singleplane, works fine with my Sniper, done some tweeking and no issues, runs great.
Question is if a dualplane will improve it and the million dollar question: is there a way to fit it under a stock BB hood, not L88...

js1977

I understand I only have a small block (350), but to kinda give you a reference. I have a 75 L-82 with a performer intake and a edelbrock AVS 2. I put an edelbrock air cleaner (part #43662) on it. It lightly touches the hood when closed so I had to order a K&N (part #E-3740) air filter which is 2.31 inches vs the 3 inches Edelbrock filter.

BTW
I had to bend up the air cleaner base (14 inches) to clear the Pretonix HEI distributor.