FiTech 2bb EFI coming

gus91326

Well-known member
Supporter 2018
I saw some pics from SEMA that shows the Fitech guys are getting ready to put out a 2bb fitech system. Sounds like it will be a boon to a lot of folks that have been wanting to upgrade.
 
I wish good fortunes for the guys. Well done on having a crack at the 2-bbl side of things.


A boon to a lot of folks that have been wanting to upgrade? I seriously doubt it.

Good efffort guys, but I saw that the system has been previewed in part before on a Jeep I6. What it suffers from is the typical disease of ghosted entrance supply to cylinders 1, 2, 5 and 6. Idle fuel supply will be psychotically swinging, and the ECM will be kept busy trying to hold it all together. I'm certain the team have done the work, but I doubt it'll ever work properly.

It supplies to the cylinders 3 and 4, and its just another poor distribution Holley 2-bbl base.

Its seriously like no one learned from the excellence of the best twin and triple carb in line six cylinder cars from the 50's, the Nash Kaiser, the Hudson Hornet, the 53-57 Chevy Corvettes. And the Offy trip power in line sixes.


Just adding more fuel in one spot in a six cylinder engine, and running it through a modern ECU, won't fix the horrible air fuel mix distribution.

Better off with a grinder, a steel plate, and a late model log head and a properly mounted 2-bbl Autolite, Motorcraft or Holley.

Or buying the Vintage inlines head and making a proper 4-bbl go of it with a much better system

https://www.youtube.com/watch?v=F-PouTapWTg

 
Soldmy66":gdz34xp2 said:
Sounds like two of them would be nice ... with the right spacing on the log.


No, same issue is that spiltting a system is impossible the way they've got it set up. That's what really irks me about a downgraded 2-bbl Throttle body EFI. Why even bother if you can't split it?

I just shake my head. Why would you even try to cram 250 hp down a 2-bbl EFI on a six.

Two 2-bbl EFI's, how to you lash it together.

The Americans were doing 4-bbl Slant Sixes and AMC 4-bbl concepts back in 1963.

As a follow on from that, Aussies got it right back in 1970 with the 4-bbl 245 E34 Hemi in line six.

Better head, better induction, big old 4-bbl Carb....






Unless it has a great intake manifold, a 2-bbl never can work on any in line 6




Anything else smacks of cheap and nasty....

IMG_1863.jpg


Anough of the ranting, I've cleaned the spittle off my computer screen and good luck guys...
 
X, how do you feel about the merits of 2x 1v TBI? On the log head of course. I asked this question a while back in the FI sub and the consensus was to go 2v TBI in the center.

Bill Hamilton successfully pulled off 2 1bbl Chevy TBI's on a Chevy straight six a while back. I think the concern there is the added duty cycle to the 4 cylinder 1bbl injectors.

http://www.binderplanet.com/forums/inde ... lt.120966/

https://www.trifive.com/forums/showthread.php?t=116377

I think I've seen a video of this car running, but I can't find it now.
 
Hopefully I can rework my tone a little. Its not based on what I do, but what you can see yourself doing.

Based on the expert work I've experienced first hand with the Corvette multiple point Crossram and Crossfire, there is no way I'd "personally" use FiTech stuff in a 2-bbl situation due to the shot gun splatted of trying to level one caterage of lead into six holes.

I'd spent 50 bucks on two HSC 2.3 carbs before spending a cent on the FiTech...see below


GM went through this through the Maliase 1978-1981 and Alphabet Soup Era (1982 to 1992, the death of English letters, start of Greek).

The issue has never been that TBi doesn't work, its that TBi doesn't work well on in line sixes.

Ford used Nissans Pathfinder VQ30E Throttle Body Injection on its 1987-1991 EA 26 3.2 and 3.9 engines....it was two K car Chrysler carbs in one 32/36 style package.

To get that 2-bbl TBi to work, the intake had to be like this.....

ze6a2ese.jpg




to make it work, it needed major 1968-1996 Argentine ME 188/SP 221 like 2v manifold surgery details

200me2.jpg


Aussie_Falcon_M_code_170_HiPer_250_2V_versus_Argentina_ME188_SP221_with_US_2_BBL_CFi.jpg



I would find a 165 hp CrossFire Z28 5 LITER 305
205 hp L48 Crossfire 1982, 1984-1986 Corvette system, which is just two 4 cylinder throttle bodies.

Them before I'd spent any money on an 2-bbl EFI.

Even if its a company as well respected as FiTech is.

Factory 5 and 6 liter twin point TBi EFi uses the most delightfully simple to balance systems ever made.

I'm swearing, and using the Chevy word, but....MOATB! (Mother Of All Throttle Bodies) .....https://www.corvetteforum.com/forums/c3 ... s-ram.html

The idle tracking the TBi 1 to TBi 2 balance, its all been done.

Every early Chevy Cavalier or Iron Duke TBi car is your friend.


And if you've ever seen a Rambler 196 engine, the arrangement of the two carb set up that OpelGT+3point3 is doing is perfect for twin 1-bbls.

memberlist.php?mode=viewprofile&u=251721

OpelGT+3point3":1p4203mt said:
I took a few pics showing the size of the intake ports and the angle I cut the tops off; toward the valve cover. Plus with some studded head bolts inserted to provide an anchor for eyebolts to attach the new intake. I cut the angle because I want the intake lower; coming out level instead of upwards. The upper section I angled off was the inner radius of the curved port; it will be a smooth transition without any severe angles. My head is cast steel as denoted by the grinding sparks; light yellow and very long, instead of short orange like cast iron. I'll try again later to upload pics. I just want one small four barrel, like a 390 Holley or an old WCFB Carter or Four Jet Rochester. Something about 400 cfm with vacuum operated secondaries.


w3LwNX.jpg




I've worked with the Wrought Cast Carters before, both Double (WCD) and Four Barrel (WCFB)
Mainly GM crap like Buick 8's and 62 Vettes. Before those in 2011, I was probably influenced by the GM in line Pommy sixes, and the whole thing was the simplicty for setting up multiple carbs from the indermediate shaft on the firewall. Falcons have that same key idea...simplicty!

The WCD I like more because the parts situation is easier, and again, I like the easy GM linkages, and the single Twin H Hudson Hornet air cleaners that come with them.

daytona07turkeyrun.jpg


63-rambler-196-block-left.jpg


6237248331_9506018ef6.jpg

6243374393_c72446fb34.jpg


If you use the Rat Roster Cross Ram Smoky Yunick style plate on a 6 cylinder,

I started in 2011, but got busy earning a living

IMG_6741-1.jpg


My background was twin carb CrossRam and Twin throttle body Crossfire Chevy intake manifolds, so when I found the old AMC/ Nash six cylinder stuff, it was a slam dunk to do it on a Ford log head six.

4-1969-crossram-hemi-z28-camaro-engine.jpg
 
Not very easy, but at 25 bucks a throw for one complete set-up, certainly doable. The offy is too tall and too small in porting to work well, so your better off making a low deck welded intake like on rwbrooks50's website

http://s529.photobucket.com/albums/dd33 ... 0Ranchero/




The TBi is just a 1946 Holley with the worlds best TBi injector. It's linkage is pure 1978-1983 Fox 200, and 1984 US and 1984-1987 Canadian 1949 and its feedback versions, the 6149/6153. A 1946 Holley is driven from the back of the carb pointing to the firewall on the rear drive Fox, but the 1949/6149/6153 and TBI are actuated from the drivers side on the West East engined Tempo. Oh, and the Taurus 2500 with 100 hp from 1986 to 1990. Plenty of messed up rental or repmobiles around to pick from in a car yard, if you know what to look for.

You need to study these pictures

Donar engine--->

Sitting clocked anticlocwise 90 degrees on one of our forum members efi Mustang
|
|
v


And a view of the TBI unit from my mates US market 85 Alaskan Ford Tempo 2300 he imported to New Zealand



There are four problems to cover off first


1.As far as TBI's go, they are monsters, two of them would be enough to wake up make a 5.7 84 Crossfire Corvette or 5.0 235 hp TBI Camaro. The problem is that the delivery pounds per hour is set for 90 to 100 hp each depending on color. Three would be almost 285 to 300 hp. Tripower kits are normally made for small upgrades in the 120 to 220 hp range, so three stock blue or green injectors are over kill unless you really work that 200 with a huge 278 or bigger cam, 10:1 compression, better ports, big exhast and a set of close ratios and a demon diff ratio to cope with an overall loss of low end torque. On the basis of sizing, three TBi's are the same as three HS6's or CD175's like used in the 282 hp the 1967 to 1972 Aston Martin DBS 4.0.





2.Biggest issue is that the Offy or Edlebrock intake is too small for the other carbs, always has been since they were first devised.This limits power potential for any given combination to about 180 on a 200, maybee 200 on a 250 with all the right mods. Cam timing needs to be altered to build pressure on these carb configuations because the 200 and 250 engines are just like a making a worked 400 hp 460 breath through a 500 cfm 2-bbl Holley. There isn't the room to hog the Tri Power intake out to 1.75" (or 45 mm) for each barrel. In the Offy for the later EO head, each intake is only 1.09" or 28mm for the outers and whaetever the inner is. The Weber 34 goes on them, but they are just 29 mm venturi carbs. You'll have to make an adaptor to merge and waist the 1.75" hole to 1.09" at the outers(45 mm hole down to 28 mm). The TBI and carb share that huge 1.75" throttle body, same as the US and Canadian carb version of the Tempo.


3. The inlet to each of the three throttle body injection units is oval shaped, and so it can't go in the stock postion, it has to be turned clockwise (as you look at the front of the car from the radiator) through 90 degrees to allow the three air inlets to point over the rocker cover. I've been told the air horn on the TBi is able to be clocked without moving the throttle body, but I've not seen that.

That makes the linkage simple as long as you have space to use the stock Offenhauser linkage off the spring side of the Tbi. There isn't the room to run the linkage between the rocker cover and TBI units. Normally you should never operate an accelerator from the other side of the carb shaft, but on the TBI, it should be okay.

4. The TBi operation. Basically, you can use the stock TBi and convert your Duraspark to Thin Film Ignition, and run the stock EEC4 Tempo computer on the center carb, then trigger the outer carbs with a second EEC4. That way, up to 60% throttle, you'd be using up to 60 hp, then the others would start to open up, and then produce up to 285 hp.

You'd use a feedback O2 sensor, and you could use the stock 1981 to 1983 B and X code 3.3 iron header with a steel port divider, and a gutted pellet 'football' cat from any 81-83 3.3 powered Fox.
 
On the 1985 CFi Mustang and Capris with the 180 hp 5.0 HO engine, the intake gained a new design, and a new flow dam to redistribute the air fuel mix.
CFi and TBi cars have an exceptionally poor "Roosters Tail" and it means the cylinder to cylinder air fuel distribution is totally out of sync, especially so on in line sixes.

Fords Engine Development team had to redesign the 1984 engines intake manifold because the extra 40 to 50 hp the 2-bbl CFi had created a warrant issue due to fuel distribtion front to back. Some aluminum flow dams were incorported to swing the air fuel ratios back. From 1980 to 1985, they had gone through a number of intake revisions to cover off the problem.

CFi is a very bad system with a Holley 2-bbl type of throttle body....you are better off with anything else, although it works if the curb idle air fuel mix is stable. I don't think it was very good on the 1980 129 hp version, and it certainly wasn't by the time the last 180 hp CFi 5.0 rolled out in 1985.

"Wang-ing" a 2-bbl CFi on an I6 won't be easy without a lot of checking. There is no proper method of isoloating front of engine to back of engine a/f to cylinder differences, or cylinder to cylinder differences. I'm aware that FiTechs system impinges on an anular ring to improve atomisatin, but that doesn't ensure the air fuel mix is evenly distibuted like a carburettors air fuel is.

This scenario plays over with 2-bbl carbs as well. Most 2-bbl Holley guys with 2-bbl carbs on v8's are aware of this issue. 215 Buick Olds Pontaics and Rover 3500'S; add a 4 bbl, its not usually an issue. Its to do with having insufficent runner volume for a 2-bbl carb to avoid a flow distribtion emerging. If the intake is enlarged, then the flow distribution goes away. On a Ford I6, I can't see how a log headed 2-bbl conversion FiTech EFI could ever aviod this scenario.
 
Excellent timing there X as i actually was considering doing this exact setup with A turbo on a 200. The tbi units are rather simplistic and from what ive heard only run 12-14 lbs and yes the top hat or snorkel whatever youd like to call it can be rotated in any 90, 180, 270 degree increment as they use locating studs and holes to "lock" them in place the only issue i had heard of was trying to boost reference this type of system and trying to tie all the throttle bodies together and also how to split the boost charge tube to go to each individual throttle body. I hadnt heard of any issues of fitting it to a offy setup mainly cause i dont think anyone has tried, but in theory it should work. But then again thats in theory.
 
don't 4get, Cman, that's all been worked out on our 2 forums:

Turbo
/&/
FI.

C "Board Index" above.
 
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