Change or Not to Change - That is the ?

[Brian Tucker]

Bill usn 1 it was nice meeting you at the RMIHR, but since we have talked I have a few questions.

I have been running a Holley 2D for about 3 years and have never had any problems until this year. I just recently lost an injector. It was easily replaced since I found a spare.

I have a 73 Scout with a 345, Mild Cam (Schneider 15-100), Holley Projection, 4.09 gears, 33x12.50 BFG/MT, Jacobs Ignition, Pertronics Ignitor. I average about 13 mpg. I have done some research on mpg increase with adding FI but I need to here what those of you with IH motors are getting with the GM FI Set-up….

I have a bug in the back of my mind about changing to the GM set-up (Thanks for that one Bill). If I could get my scout to average 16-17 mpg I would drive it everyday….. So- the question will I see big enough change to move from the Holley system to the GM controlled System. What improvements would I see with the GM over the Holley.

Brian

[Bill usn-1]

Hello again,
If you have a working FI system I would not be in a big hurry to change it out. You really won't see any imediate gains.
I wanted FI and chose the GM for the control and price. (300 for mine 1,000 for Holley)
When the holley works it works fine. But fuel is only 1 part of the equation.
Spark is a big part and that's why I like the GM system.
You could tune the holley to work just as good as the GM, it will just take a little time.
If I drive slow, I can break 16mpg. But I don't drive slow!!!!

You will need to get a distributor spring/weight kit. I think mallory and accel sell them. Try summit or jegs. Just don't ask for IH they will probably say no. Or try to find a speed shop that recurves distr's.
you will have to play with the base timing, total timing, and the rate of advance, which is by spring/weight selection.
I run a different timing curve in my trail scout then in the wifes street scout. You will have to play with it till it is what you want.
The plus side for me is, if I don't like it I just come back burn another chip and go again.
You will have to pull the dist apart to make the spring change.
It's not harder just different.
If your not closed loop(O2) you may want to look at that. It allows the system to adjust and compensate for varying conditions to optimize the AFR.
Another option that I am looking into myself is to replace the injector pod with a GM pod. But I haven't tested them with the Holley computer. It will give you better injectors. Something to keep in mind if you have another go bad.
Just to give you an idea:
I run my base timing at 15btdc. I have my total timing set at 41* so that's about 26* of mech/vacuum advance. If I had them!!!
Max timing is at hyway cruise for fuel economy.

So....the question is ...How much have you tried to optimize your system, and are you closed loop?
Between the 6 IH's I have done or helped with, I have burned over 100 chips. How many times have you recurved your distributor? My guess if you are like I was...none.
We just don't think about it much.
You made a lot of changes to your motor and your scout. But I doubt the dist was changed to match the new combo.

Let me know what you have and do a little playing.

HTH

[Eagle-Mark]

So many people don't have a good running Holley system so feel privileged you do and keep it, they don't even bring much money used except the TBI which is two inch bores and the small block Chevy guys love them. Bill's right about the ignition end. When I was looking into going fuel injected the GM system had all ends covered. Fuel and spark so why go half way for more money with a Holley.
Your fuel management is in so now it's time to work on the advance curves for finer tuning, just like the old days springs and weights.

My fine tuning is not done yet but my mileage ranges from 12.2 to 13.4 MPG that's with 4:09 gears so I am happy.
Also mileage while pulling a 20 foot travel trailer with the A/C on in close to 100 degree heat from Seattle to Coeur d'Alene Idaho was 11.2. Thats more than I was getting with the carburetor and no trailer.

[Brian Tucker]

Bill and Mark,

You guys are right! I have not worked with recurving the distributor. What steps am I looking at to change that. How difficult is that? Are there any books available?

I have seen kits available at auto parts stores that work for the GM Dizzys. Are these the same spring and weights that I would need to change my set-up? Or do I need to find a specific kit for the holley? I thought most of the weight and spring kits for the dizzy were universal.

Let me know on the weights and I will start making changes this weekend. New project --- Yea!!!! I like this kind-of stuff... I can check performance with my changes by driving the truck back and forth to work. I have a 30 miles drive on the interstate so that will make a good test.

FYI-I did call the manufacture that makes the distributors. They stated the Vacuum advance is between 5 and 7 degrees. The mechanical advance is 7 - 10 degrees. This is for all IH remanufactured dizzy's.

[Bill usn-1]

http://members.aol.com/DVAndrews/timing.htm
http://www.nastyz28.com/perftune.html
http://www.telusplanet.net/~chichm/tech/lucastuning.pdf
http://www.442.com/oldsfaq/ofign.htm
Here are a couple of links just to get your taste buds going.

And here are the stock specs.
http://www.justinternationals.org/fu...tion-faq-1.htm

[Brian Tucker]

Is it worth changing my four barrel intake to a two barrel intake? I already have the adapter for the four.

Brian

[Bill usn-1]

Nope! Works fine.

[Binderman]

Brian Small world! How are ya? Have you settled down from all the excitement from RMIHR yet? Have not talked to Shawn yet about his trip up there. He is probly quite busy this close to the start of school.

Now to my question. All this talk about adapter plates got me to thinking about my conversion. Has anyone got or found a source for the aluminum plate needed for the adapter plate construction? Have been looking at different things like large aluminum oil pans and road signs,skillets, etc and have had no luck finding anything i think will work. Would like to have something about 3/8 thick I think.

Have thought about seeing if the butterfly plate on my 2300 will machine out and be usable. Anyone done or looked into it already? Can't see paying the $$'s Holley wants for theres. I wonder if AFI sells just the plate like Mark got with his kit? I am challenging myself to see how cheap I can do my conversion. Any thoughts? Thanks again to everyone with all the help so far!!!!!!

[Eagle-Mark]

I don't know if getting to cheap is worth it sometimes. At the local metal shop here in CDA they cut pieces of diamond plate and such for me all the time for $2 to $10 cut to fit.
I priced a piece of one inch thick aluminum the size of the adapter and they quoted me $8.
They are glad to make a few bucks on the left over scraps they get from big paying jobs.
We are a small town too! Just check some in your area you may be surprised.

[Bill usn-1]

If you swing through Dallas I have spare plate. But you have to cut it!!
I've been lucky, just finding a piece here and there.
Like mark said, if you find a metal shop you would be amazed at what is in the scrap bin or dumpster for that matter!!!(been know to dumpster dive for some parts)

[Binderman]

Not scared to dig into some trash myself!! My mom has always said she married the caucasion version of Fred Sanford and later had his sun Lamont.

Have not been to the recyclers or any BIG metal shops or fab businesses yet, just been looking locally.

With my bank account cheap is always better!!!!

Bill may have to wait till the Roundup if I need to bum a piece from ya. Thanks for the offer!!

Mark Can you still get the plate you mentioned for that price? If so I will be more than happy to pay you for your time also. Have bought some "drops" myself for different things but only in steel so far. Thanks!!!

[Eagle-Mark]

I'll stop by and see what they have Monday.

[brendan]

I was told that you don't want plate, but rather billet stock. I bought a piece on Ebay big enough for two adapters for $30 with shipping

[Tom Mandera]

Originally posted by brendan
I was told that you don't want plate, but rather billet stock. I bought a piece on Ebay big enough for two adapters for $30 with shipping

What's the difference between "plate" and "billet"?

Isn't "billet" a fancy word for "one piece"

A "billet" wheel should be made by starting with a block of material and machining away the parts you don't need.

You just can't have a 2-piece billet anything.

And as such, isn't a hunk of plate one-piece?

[Binderman]

After watching 6 hours of American Chopper this weekend (while stuck in motel room) I think Tom is correct in saying that Billet is one solid piece of something.

Anyway they were CNCing wheels for the bikes out of Billet wheel blanks or a one piece wheel. Wish I could be around that whole process some day.

What would I do without the Discover channel or TLC?

Ya learn something daily!!!

Thanks Tom!!!!