slant fuel injection opinions

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vitamindart

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ok, I have been mulling over fuel injecting my slant. fighting this 450 Holley is pushing my limits. just want to enjoy the car. ( I did add a wideband to try helping, just need to wire it up)
looking at the FiTech ( with the power adder option for later ) have considered getting a rail and set of bungs to add multiport ( maybe mega squirt ).
the car is a 1966 Valiant with a warmed up 225 ( ported head, bigger valves, cam, hurricane intake, Clifford headers ) with a 904 and a nice stall.
I have messed with Holley's for years never had one fight me drivability wise like this one.
my guess its related to the carb being somewhat oversized for its use. ideally I would have run a 350 2 barrel but, had the intake and carb already.
 
I suggest that you fabricate your own intake manifold from aluminum and supply a throttle body from a 4.0L Jeep H.O.. Many years ago I crewed on a G/gas '37 Chevy coupe with a 302 GMC 6 cylinder & a Hydro Stick . Anyway , we made our own intake out of aluminum with 2 Holley 600cfm carbs . It was awesome fun . I know not everyone has fab skills but it would be fun to built an intake for a /6 that works .
 
Addendum : What we learned was that inline engines with a single carb have fuel distribution problems . the end cylinders ran lean and the center ones ran rich . Two carbs fixed the problem . the new problems were to get the two carbs to run in sync. We did that with vacuum . Maybe 2 throttle bodies and injectors would be better . We learned to read plugs fast.
 
@pishta has made his own I do believe.

Also, I would be interested in that 450 Holley if you are going to sell. They are known for being very difficult to deal with.
 
This guy at GILL Welding is a genius . He is not clear if he is selling them or made to order or ? But this is what was my reference in my previous post . If I had a slant it would be on it .
 
There is Megasquirt which is incredibly DIY and versatile. Go visit "Binder Planet" (About International Harvester products, AKA "Corn Binder" and read the tech page on EFI. Some folks over there have drilled intakes for injectors and used various controllers, including GM computers which have a socketed chip and for which you can burn a new file

"START HERE"--Fuel Injection FAQ--"START HERE"

Also, consider TBI to keep things simple. Somebody, Holley? recently came out with a small 1 or 2BBL setup aimed at Jeep 6 whangers

Here's one based on the Holley 2300 base but I don't think that is the one

Holley Sniper 2-bbl EFI Self-Tuning Kits & Accessories | JEGS

Also, consider something like an old K car TBI driven by Megasquirt, etc. In other words a throttle body and injector
 
Hi, I work at Gill Welding & Fabrication and control most of our social media.
@Keystone thanks for the referencing us.

@383Scampman We've had a long road getting from one offs to production. Everything is CNC machined and then the parts are hand TIG welded. We are doing our best to keep up with orders, but we are currently on a wait list. (Usually 3-6 weeks) We appreciate the kind words and good feedback.

@vitamindart We carry both a Mark II and a Mark II-R at Gill Welding & Fabrication. Both manifolds can be turboed both manifolds support a Jeep 4.0L throttle body. The Mark II fits more stock engine bays than the R. The fuel rail that comes in the kit is -8AN which is drilled and tapped both ends so you can dead head the fuel system or run the regulator after the rail. We carry Megasquirt ECUs, wiring harnesses, Torqstorms, O2 sensors, Injectors, Pumps, etc. We can package deal anything you want and help you get a decent discount. Our manifold with a full system kit can save you over $100 not counting a forum members discount.

We also can modify any aluminium intake. We install our 45 degree bungs and our -8AN Fuel rail. This option can be a lot cheaper for those who already have a manifold they want to keep.

Multipoint is the best for fuel distribution, and with the right controller you can compensate for inefficiencies for an individual cylinder.
 
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Depends what you are after. excellent reports on fi tech tbi used on slants. For a mild slant im sure tbi would suffice.

The extreme end of n/a and force fed probably needs port.
 
all great food for thought, I have a hurricane intake I could add the bungs to. not sure I want to modify it. fuel distribution is a big part of the question. probably the only reason I haven't pull the trigger on the FiTech or other throttle body injection already.
RRR I will keep you in mind if I dump the 450 ( it has had the choke chopped off )
 
There is Megasquirt which is incredibly DIY and versatile. Go visit "Binder Planet" (About International Harvester products, AKA "Corn Binder" and read the tech page on EFI. Some folks over there have drilled intakes for injectors and used various controllers, including GM computers which have a socketed chip and for which you can burn a new file

"START HERE"--Fuel Injection FAQ--"START HERE"

Also, consider TBI to keep things simple. Somebody, Holley? recently came out with a small 1 or 2BBL setup aimed at Jeep 6 whangers

Here's one based on the Holley 2300 base but I don't think that is the one

Holley Sniper 2-bbl EFI Self-Tuning Kits & Accessories | JEGS

Also, consider something like an old K car TBI driven by Megasquirt, etc. In other words a throttle body and injector
Thanks for the IH link. I forwarded it to a friend who is into tractor pulling.
 
alright, pulled the trigger on a FiTech set up. Should be here in a few days. will start pulling the fuel system out this weekend prepping that car for the install. figured now was a good time to upgrade the old 8an lines to some 6an Teflon lined ones. that opens up the e85 option for me. I am lucky enough to have a pump 3 miles from the house. that should help If I ever get some boost.
 
alright, pulled the trigger on a FiTech set up. Should be here in a few days. will start pulling the fuel system out this weekend prepping that car for the install. figured now was a good time to upgrade the old 8an lines to some 6an Teflon lined ones. that opens up the e85 option for me. I am lucky enough to have a pump 3 miles from the house. that should help If I ever get some boost.

Nice...i keep wanting to also.
 
Addendum : What we learned was that inline engines with a single carb have fuel distribution problems . the end cylinders ran lean and the center ones ran rich . Two carbs fixed the problem . the new problems were to get the two carbs to run in sync. We did that with vacuum . Maybe 2 throttle bodies and injectors would be better . We learned to read plugs fast.
That will always be a concern as long as you keep the intake "wet" on an inline engine. I designed and almost have ready to cast a front mount throttle body EFI intake for the slants. Got a lot of interest on the other forum, but i've also been casting a similar intake for the Chevy inlines also. I have several guys in Brazil making almost 900 HP with them. Turbocharged of course! But they work good.
 
I had a 450 on my slant with a comp 264 cam, 0.03 off the head and block, hooker headers and dual exhaust. Got tired of fighting it, and put on a 390. It is much much better.
 
started my FiTech install this weekend, didn't get as much time to work on it as I planned. Had to replace a kitchen sink...… worked on it a few hours on sunday. running all new PTFE -6 lines. tank is solid and looked ok inside so I just punched a hole for the return. hopefully the rest of my parts will show up and I can get this thing running again soon.
 
all back together runs Great! fired right up. need to tweak the hard acceleration but so much nicer. took it out for a nice cruise in between all the rain. hoping to turn it into my daily for the summer. cant wait to start considering boost options now.

RZXU6323.JPG
 
All the naysayers on here will tell you how awful the fuel distribution is. You need mpfi and megasquirt!!! Need!!!!!


Nice work. Id love one of those myself. Great for a daily!
 
all back together runs Great! fired right up. need to tweak the hard acceleration but so much nicer. took it out for a nice cruise in between all the rain. hoping to turn it into my daily for the summer. cant wait to start considering boost options now.

View attachment 1715341989


What system did you go with? I’m on the fence with FiTech as I don’t think I can tune it down far enough for a stock 225. I’d love to go with the 30004 system and add boost later. It shows 200-600 hp.
 
I have the 30004 600hp PA on mine. it was the smallest PA system they had listed. so far seems to be working great. need to get some decent weather and some time to put some miles on it.
 
I have the 30004 600hp PA on mine. it was the smallest PA system they had listed. so far seems to be working great. need to get some decent weather and some time to put some miles on it.


So works been done to engine and she runs well. I’m worried on a yet to be tinkered with bone stock 225 with a Clifford intake it will not tune down enough and bog out.
 
its all adjustable, you set the # of cylinders and cubes. then fine tune from there. my slant has the block milled .120, cam, ported head w/oversize valves, hurricane intake and a Clifford header. runs better with the fitech than I was ever able to get with the 450 holley. with the carb it was one or the other, either it idled great, cruised ok or pulled decent. never was able to get more than one on any given day. got tired of taking it apart to make changes. this I can pull over, tweak the tune and drive away. not that I have had a lot of seat time yet but, what I have has been a bunch better. I will let it tune it self some before I start tweaking it.
 
All the naysayers on here will tell you how awful the fuel distribution is. You need mpfi and megasquirt!!! Need!!!!!


Nice work. Id love one of those myself. Great for a daily!
Looking at vitamin's pics, that's an Aussie Hurricane intake,....much better distribution than stock or Offy/Cliffy styles. I'm still waiting for a head-to-head intake dyno showdown............
 
its all adjustable, you set the # of cylinders and cubes. then fine tune from there. my slant has the block milled .120, cam, ported head w/oversize valves, hurricane intake and a Clifford header. runs better with the fitech than I was ever able to get with the 450 holley. with the carb it was one or the other, either it idled great, cruised ok or pulled decent. never was able to get more than one on any given day. got tired of taking it apart to make changes. this I can pull over, tweak the tune and drive away. not that I have had a lot of seat time yet but, what I have has been a bunch better. I will let it tune it self some before I start tweaking it.


Maybe I can PM you and you can give me more details on your set up and what you are running. I have access to a decent machine shop that doesn’t take both arms and legs at once lol
 
all back together runs Great! fired right up. need to tweak the hard acceleration but so much nicer. took it out for a nice cruise in between all the rain. hoping to turn it into my daily for the summer. cant wait to start considering boost options now.

View attachment 1715341989
thas is a clean install. The injectors are most likely modular so you should be able to find some smaller ones. The size of the injector determines the minimum duty cycle of the controller. Smaller injectors dont need a very short duty cycle, which the big ones need to get a proper idle on a smaller displacement motor unless the fitech cuts an injector(s) for an idle. Youll want to size the injectors to your maximum HP and not much more. Like having a dominator on a 273, it just wont idle properly and wont be that tuneable in its A/F ratios.
 
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