Rkreigh

I've been thinking alot about this lately. going with a small set of primary injectors, and race gas or e85 on the secondaries.

it would allow easy calibration of part throttle and idle, and bring on a set of monster injectors with a wide band for the secondary.

looking at either a megasquirt 3 or if dollars allow a big stuff to be triggered by a hobbs switch when the boost comes on.

I know the folks at wheel to wheel did this with the "dual rotex" nova that they built and although expesive, I think it would be a great option.

now that there are more cas alum manifolds available, a nice single plain with dual rails would be pretty cool.

I'm looking to get to more power and take advantage of a wide band 02 for the WOT and leverage the factory system for the integration with the car

the ZR-1 and ford GT both use a "dual injector" strategy and I've always thought it was a really cool idea.

pump gas for the "primary" and pure alchy for the seconday is what I'd like to try. I have a pretty big alchy tank in the trunk already and room for more if needed.

any thoughts??

Corvette-Chris

Why not just get properly sized Injector Dynamics injectors?

robert miller

Other than saying you had it and the $$$ it would cost. To me the less parts the less something can go wrong.. Robert

LinearX

One of the big complaints over the years has been idle quality/idle control with large injectors. I'm sure that has changed over time to some degree, but if idle control is still a major concern, then having a smaller set of injectors to idle and cruise on could be easier to control. Of course, the controlling ECM would also play a large part in that.

Doug Levin was doing something like this years ago with his supercharged Vipers. He had an extra injector or two that ran race gas into the intake tract to make up for the lack of fuel control in the ECM.

Mike04

There are quite a few in the Viper community that run a second injector per cylinder.

I've had good luck with the Injector Dynamics 1000cc injectors for idle quality and over all performance. You might want to look into that brand, they make some monster size injectors.

LinearX

Yeah, it is also popular in the drag racing world for big inch twin turbo cars running alcohol.

I know that idle quality was a big issue with Turbo Buicks back in the day, but I'm sure that injector quality and ECM control has come a long way. I like the KISS method, personally, and would only run a second set of injectors if there was just no other alternative.

robert miller

I know BLOWNBLUEZ06 loves them and says best one,s he has ever used in the car. They make some giants in these. If I do any more to the car I am in high 90% at WOT in the 83 inj, I have now for sure will look at the 1000cc if I go to something diff... Robert

0CK@UPPCOS

We did this on the 3000Gt, it runs E85 for a primary "cheap" fuel, and pure Meth for a secondary. It was tuned with AEM EMS, which has procivions for extra injectors, including transition capabilities. It is possible, but kind of a headache to tune.

No HOB's switch though, run MegaSquirt with a boost reference, cap the fuel delivery on the primary's at "x" psi of boost, and start the MS bringing in the secondaries at the same point. SD tuning on both is almost a must.

http://www.youtube.com/watch?v=bCocb...&feature=feedu

CK

stevieturbo

Nothing new about 2 inj per cylinder.

I run a pair of 60lb's per cylinder in a modified carb intake. The ID1000's werent available when I put mine together.

0CK@UPPCOS

How are you controling your second injectors? Is it through a standalone with a second fuel or piggy backed with the primary fuel?

CK

stevieturbo

My car is a conversion. I'm using a standalone ecu. I use a single fuel source.

I just opted for this as it was 100% full proof for any power level I might see, and would offer me no problems whatsoever in terms of low end fuelling.

Plus I already had 8 injectors, so overall cost wasnt massive to upgrade.

I had previously been using 8 x RC750's, but just didnt like them at all and I needed more fuel.

Rkreigh

this would primarily to run dual fuel. pump gas on the primary injectors, and methanol on the secondaries.

by having two fuel systems and two fuel tanks, curing the capacity and cold start issues is improved, and I can take advantage of the high octane of either methanol or race gas on the secondary fuel system with different tunes.

what I'm looking for is more info on the "hassle" of staged injectors

I'm only running 70 lb injectors now and it seems the cold start performance isn't that great with the wide band showing pretty rich so more tuning on those tables is likely needed.

also what would be the best intake manifold to take advantage of dual fuel rails

like to hear more about the best ECM strategy (stock plus a megasquirt) or just convert over to the megasquirt or bs3 or other computer system

I like the idea of wideband control to help with wot and tuning too.

wish the factory ecm could have an operating system update to run a wide band. that would be cool!

stevieturbo

Doesnt EFILive already allow interaction with the wideband for tuning ?

0CK@UPPCOS

Most all my experience with this is in standalone units like AEM EMS, that has provisions for both injectors, and can handle transitions between them. BUT..... In theory, all you would have to do is tune in SD, at a certain PSI (call it 8) anything above that flat line it so no additional fuel is added. Exactly the opposite on the MS, just zero out the fuel map until 8psi, then gradually add fuel. The only downside to this is if the secondary fuel system fails, the primary won't, and then you'll be hurtin.


CK

stevieturbo

Ive little experience with the factory PCM myself. All my tuning is done via standalone's

But I see no reason why your proposal would not work when using factory + standalone for a dual fuel system.
I think Parish the truck guy already does something similar though ?

396375

IMHO it's more things to screw up and there are lots of 1000+HP cars running around with Meth that drive just fine.