Anyone ever used Stack Injection ITB setup?

Eric B

Eric
Eric, I'm about 40 minutes South of Dennis' shop.
My car is up there now. Dennis and his crew are a great bunch.

The base tune in the ECU was not giving us results down low, so we are using a "prestigious" local tuner to review the ECU and the tune. The engine (built at Craft Motorsports) came with a basic ECU, depending on what the tuner says I might upgrade that ECU so I have more options once I take delivery of the car.

E
 
I was speaking to a tuner regarding using something like an Omex 710 and he said he would just tune it on TPS and crank sensor as if I went with Jenveys it’s unlikely they’ll have common plenums in the manifold etc. Naturally I understand that the vacuum signal is low at idle etc but wouldn’t it be a better tune with a Map, TPS and atmospheric/temperature sensor?

Now obviously the borla etc setups use MAP and TPS, then you have got your add ons like cam sensor and O2 sensors in the exhaust collectors etc. Will be using a wasted spark setup for the ignition.

It’s going to be similar money for borla/Jim inglese and the Jenveys so if you all had a choice which would you choose and why? Obviously a UK company for support is always a massive pro point but it seems that it’s a much more basic setup than the other two. . . . However as I’m not utilising sequential ignition etc would you think that it being more basic wouldn’t be a problem.

So basically if you were to buy a set of ITBs now, what would you buy and what sensors would you run?
 
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what would you buy and what sensors would you run?
o2 sensor
Crank position sensor, even if you are going to run a stock dizzy.
Map sensor
TPS
Air temperature sensor.
Cooland temperature sender. ( very handy for cold start enrichment settings )

I have Megasquirt controling the injectors and ignition, still running a stock dizzy, distribution the spark to the plugs (single coil with IGTB) but igntion is fully controled by Megasquirt which gets its signal by a 36-1 crank trigger. Crank trigger is way more accurate.
You can not live without an 02 sensor, you need to see whats going on, even on carbs.
MAP gives you the ability to alter fuel & igniion settings under load
You can let MAP & TPS work together in % MAP DOT or % TPS DOT

Most ECU's start in closed loop thats where the o2 sensor plays a big role, fully warmed up they go to open loop, but I always like a % o2 influence.

My 50cents, carbs or injection, same top horsepower. Carbs, no hassle once set up correctly and synchronised each year.
Injection gives you the ability to get better fuel control under any condition but thats not a matter of just setting it up on the rollers within a few hours. and 8 stacks needs to be synchronised also each year.
Carbs or injection, doesn't make much on fuel consumption also.
I have spent hours in weeks, months with the laptop in the car to fine tune my ECU settings during driving conditions and I am still not satisfiet.

Injection is fancy but doesn´t ad.
Carbs allways work. no sensors to fail, no heat soak injector issues leaving you stranded for an hour to cool off after a fuel stop., carbs just a tap on the throttle to give fuel to fire up the engine.
 
I was speaking to a tuner regarding using something like an Omex 710 and he said he would just tune it on TPS and crank sensor as if I went with Jenveys it’s unlikely they’ll have common plenums in the manifold etc. Naturally I understand that the vacuum signal is low at idle etc but wouldn’t it be a better tune with a Map, TPS and atmospheric/temperature sensor?
Hi Chris,

If you IR system doesn't have a common plenum - make one. Tap each runner under the throttle plates, and run 8 small vacuum lines to a small vacuum reservoir, then feed the MAP sensor off that. Unless you have a truly massive cam - I'm talking a mega race cam - there's no excuse for not running a well tuned speed density set-up.

Cheers, Andrew
 
Looks awesome!

I’m waiting to hear back from Jim Inglese about costs in his systems for what I’m after.
Glad to hear you’ve been able to make all of the intakes work without too much difference between them. Crazy how the price differs though.
The DC&O trumpets seem to fit really low compared to the speedmaster/borla in the cobra. What are the two engines? Both 302 based?
What did Jim have to say?
 
What did Jim have to say?
he came back to me with the below :)




Chris,
Either type of EFI is $5375. These are shipped ready to install with the injectors, sensors. fuel pressure regulator, and pressure gauge on the unit. Also included are the intake gaskets, intake bolts, a German synchrometer, and setup instructions. All manifolds have the vacuum chamber for the MAP and IAC to get their signals.

Height of the Weber type EFI is 11" and the height of the conventional type EFI is 9" The Weber throttle bodies are higher and they have 2-1/4" velocity stacks, which is the same stack height as the carburetors. We can install 1" shorter velocity stacks on the Weber EFI's, which are optional. This would lower the height to 10". This is not usually done for the GT40's, more for the Daytona Coupes.

The conventional EFI's come with 50mm air horns, and 35mm air horns are optional.

Our lead-time is about 3-4 weeks right now. A deposit of 50% on any credit card will get an order started. In the meanwhile, if I can answer any additional questions, I am at your service.

Thank you,
Jim
 
Thanks Chris,

What did you end up doing?

When I spoke to my mechanic, he mentioned that the Weber EFI changes the sound of the motor. I’ve got a pretty aggressive sounding 427 Windsor, and I don’t want to lose the sound.

I’ve been doing a little more digging and think I will go with a Holley EFI system. I’ve heard good things about them and will certainly post my experience once installed.
 
Thanks Chris,

What did you end up doing?

When I spoke to my mechanic, he mentioned that the Weber EFI changes the sound of the motor. I’ve got a pretty aggressive sounding 427 Windsor, and I don’t want to lose the sound.

I’ve been doing a little more digging and think I will go with a Holley EFI system. I’ve heard good things about them and will certainly post my experience once installed.
well so far I did sweet FA haha
Thanks to working in the aviation sector my salary was reduced by 85% so far this year. Rumours of being made redundant have resurfaced again so time shall tell. I could have bought the majority of the bits needed for the build from what I’ve lost this year but hey. C’est la vie!

let me know how you get on with yours, I’d have kept it simple with a simple carb style but I simply love the look of ITBs.

I’m hoping to start my build within the next year or so. Time shall tell!
 

Glenn M

Supporter
When I spoke to my mechanic, he mentioned that the Weber EFI changes the sound of the motor. I’ve got a pretty aggressive sounding 427 Windsor, and I don’t want to lose the sound.
I wondered that when I changed from Weber Carbs to Weber EFI, but it made no difference whatsoever, it still had all the aggressive bark as before.
 
Webers change the sound of an engine compared to plenum manifold carburetion. The change to Individual runners did tend to take some of the rumpty rump out of the cam. Changing then from Weber to fuel injection/Weber style had no change to the sound.

This is what I noticed when I went along that path.

Paul
 
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