I've been thinking of rebuilding my original 78 block- not currently in the car- it would be a bored out 350, mechanical roller cam, roller rockers, solid lifters etc etc... 11.5:1 compression 450 - 475 hp with .... wait for it... Mechanical Fuel Injection. Old School Style with stacks. Does anyone have any experience with Mechanical Injection? Any input would be greatly appreciated!

Thanks,
Cory

 

I dont have any experience with them on my car, but Ive seen a fair share of them on vintage road racers.
You might have a hard time fitting the fuel distributor (whatever the thing is that sends the fuel to each injector) since it is generally run off of the side of the (spark)distributor. Ive seen some that are also run off of the front of the cam with a special timing chain and cover. This kind would be much easier to fit.
Mechanical fuel injection can be tricky to tune, along with being expensive.
I love the way that they look and sound (yes, they make the motor sound different if you go with individual stacks )
it may end up being cheaper and easier to go with an electronic injection system with stacks- lots of kits like that out there.

 

Cory, I ran a Hilborn mechanical injection set-up on my '56 Nomad for a short while. I have a couple pics of it, but they're pre-digital and I have no way of scanning them into my computer right now.

The set-up I had used a small cogged belt that was driven off the front of the engine. There was also a distributor driven pump set-up that was avalible.

The hardest thing for me to set up was a way to prime the mechanical pump. I had a fuel cell in the back. It had several places to plumb supply and return lines. I installed a Holley high GPM electric pump under the car beside the cell. I then ran a 1/2" supply line to the front of the car and mounted a fuel regulator that used a return line to the pump. (BTW, the F.I. also has a return line.)

I used the electric fuel pump to prime the mechanical pump and then supply gas to the pump while driving. I didn't have to use starting fluid to fire the engine when starting.

The injector set-up I had was off a drag car (an AMC Gremlin of all things with a very built 350. The guy who owned it had 'American Gremlin' on the side with a large painting of a gremlin on the door) Anyway, I had to get new injector tips to get the fuel delivery right. It had been set up for alcohol and the tips were wrong for what I needed.

At its best, the injection was unstreetable. It idled fine, and it went WFO great, but anything in between was horrible. (and that in between is 90% of your driving)

I know these can be set up for the street properly. If you decide to go with this, I'd use a complete kit from a manufacturer. It'd have to be easier than piecing everything together.

John

 

John, I would like to run Hilborn injection. My grandfather ran Hilborn injection on his tractor built and used for Tractor Pulling. I think he had it on a bored out 454. Solid lifter set up, mechanical rollers, isky cam... the whole nine. Just wish i still had that motor. : I've been reading about it all and just dont know exactly what its going to take to get it done. I've never worked with mechanical injection. I know if it is tuned right, if you get it tuned right, it is AMAZING!!!

 

Where can I find a kit. I've never heard of that before.

 

It can be done pretty easy now a days. The eletronic pumps that are out there today will work fine. Your best bet is to call Hilbourn and talk to them about the set up you need. They will know more about setting it up to run on the street than anyone else! Or talk with any of the FI companies such as K.J.Crawford in Rohnert Park Ca. He is one of the best FI guys around. Good Luck.

 

Thanks for the info.

 

Heres one of the complete kits:
http://www.compperformancegroupstore...ode=EFISystems

 

THAT is a TRUE HIGH PERFORMANCE efi.
you should have a target of 550hp and 17+ mpg.

.

The crap efi's that most everyone else runs are just glorified emission control devices not worth the cost over a 4165 holley.

 

Before you take the plunge on one of these systems....give me a shout.I mess w/alot of this stuff.
Like seventysixvette said......these are awesome,but made for power only really.I would go w/the newer design w/the electronics,but they are very expensive,but.......you loose alot of the guess work,and the computer tells the injection what it needs for the engine call.
I have ran Hilborns w/mechanical fuel pumps from old sprint car setups,and currently run a old school X1 w/6 custom Holley 2 barrels carbs that have no power valve provisions,so basically are dumps.And....do they DUMP!!!! Tuning sucks buffalo ***,but they sure are cool when you pop the hood at shows.Noone has ever seen a setup like I run.
Mine surges at idle,cause I have to run high fuel pressure for the performance,but the opposite to that is it blows the needles off the seats at idle,and causes surging in rpms.I also,ran a big solid cam,so little vacuum,but.....when I nail it......it will pull to 150 like it isn't nonthing!
They are alot of work tho,if you go old school.I like the old school stuff tho.Anyone can spend money,and install a new computer controller EFI to look old school,but a computer tells it what to do.Not everyone is willing to take the old school setups,do research,and pull over every couple miles to get out,and tune multiple dumps w/allen wrenches,and screw drivers.
Do give me a shout tho,if you are serious about this.I carry all this stuff,and into the unique/different stuff.

 

My problem is I like to be different. No matter how much work it takes. HAHA. And I do want to go old school with it because I work with computers and I dont want the hassle in the office, much less my car. I've got a donor motor in it now from a '74 Nova. Just a 2-bolt 350 with a 600 Q-Jet. It goes, but I want to be able to punch it and go. I'm not looking for SUPER High Performance, just 450 - 500 hp. It's not going to touch the track. Well maybe once just to see what it will turn. If I can get 500hp with old school injection, I'll do it, even if it takes tuning every couple miles. haha

 

[QUOTE=Matt Gruber;1572350533...The crap efi's that most everyone else runs are just glorified emission control devices not worth the cost over a 4165 holley.[/QUOTE]

What are you talking about? Are you saying TPI, LT1, and LSx engines will not perform as well as a Holley? Surely I am misunderstanding your comment.

 

You can Matt's opinions on all things carburated here:
http://forums.corvetteforum.com/c3-t...ggestions.html