Supercharger for my Apache

[diceman50]

Well, I finally got my 261 back from the machine shop. Then I promptly left town for nearly a week to attend the Barrett Jackson auction in Scottsdale. Unfortunately on the way home I caught some kind of cold/flu bug and was out of commission for another week. I have been trying to catch up on some other projects ever since. Now I am waiting for some warm weather so I can give the engine block a thorough cleaning with hot soapy water. I did take some pictures of the machined parts though. Still waiting for the camshaft.

[Advanced Design]

The parts look really good and looking forward to the next steps. I kind of wonder how many machine shops today even know about grinding rocker arm tips?

[diceman50]

Thanks A/D, I too wonder about that. It seems automotive machining is becoming a lost art. Pete the guy who did the work on my stuff has been one of my best friends for over 20 years and has been in the automotive machine shop business for over 30 years. I dare say he knows as much about engines as anyone in the country. I am very fortunate to have his services available to me.

[Advanced Design]

Diceman, any updates?

[diceman50]

Unfortunately nothing of any note has been done. As usual "Life Happened" and I missed my window of opportunity to get it done right away. Some other obligations came along so it has been moved to the back burner for the time being, but it is still simmering. Thanks for asking A/D.

Diceman

[RockinKees]

This is interesting!
Never have seen these superchargers.
Great to see you're building the Old School Power back in an Old School Truck!
I love it!!

[Advanced Design]

Understood Diceman. I've been enjoying your project and look forward to whenever you are able to get back on it. One of my first fascinations was engine machine work which isn't done so much today. Learned valve guide knurling, rod resizing and honing, sleeving blocks and even block boring with a Kwik Way boring bar that mounted on the block cylinder surface....many years ago now.

[diceman50]

Well, so it begins. I have been waiting for the perfect time to start the build on my new engine. Then I decided that there may never be a perfect time. So I am going to use the next few days to at least get started. Unfortunately I am leaving town next week for an undetermined stay. I hope I can get it pretty well buttoned up before I leave. Here are some pictures of the parts cleaned and sorted on the bench.

[Dan in Pasadena]

Wow, I am really fascinated by this thread. Hadn't seen it before somehow.

Diceman, if I missed it I apologize for re-asking answered questions but here goes:

1. What compression ratio will you be running in this 235?
2. How are lubrication and cooling of the supercharger handled?
Will there be (is there a need for) an intercooler?

I know very little about forced induction but admit I find it interesting. Will the custom fuel injection handle this setup without physical revision? Or will your propeller-beanie buddy (a term of affection for Engineers in my line of work) just revise the fuel mapping, etc to deal with this change?

Can't wait to see how this turns out!

[diceman50]

Thanks Dan,

I don't know what the compression ratio is going to be. I have read online that putting the 235 "848" head on a 261 will raise the ratio approx. 1/2 point. If so that will put it about 8.5 to 1. Whatever it is it should be well within the acceptable range for forced induction.

The McCullough supercharger has its own oil reservoir and is air cooled. Sometimes an oil cooler is added for max horsepower or racing applications. Shouldn't be an issue for me.

As for an intercooler I will not be using one. There are several things involved in deciding whether one is needed or not including C/R, engine size and type, cylinder head design, etc., but generally speaking an intercooler is not considered necessary if boost is limited to 9 or 10 psi. Well below the capabilities of a McCullough. There might be a slight performance advantage by using one, but that is not what this project is about. I want this to be something that you might have seen in the 50's or 60's. Notwithstanding the EFI.

In anticipation of adding the supercharger, Greg installed a new operating system on the current engine a while back. The new system will support a 2 bar MAP sensor which we installed at the same time. This allowed us to make sure it is going to work in non boost situations as well as the previous system did. So far so good. When the new 261 is installed we will run it without the supercharger until we get the fuel injection dialed in for the bigger displacement and more aggressive cam. Then we will add the blower and start over again. The object is to not add too many variables at once.

I hope I answered all your questions. If not don't hesitate to ask again.

[diceman50]

I had hoped to get my engine to the long block stage this week, but things didn't work out. I was able to install the crank, rods, and pistons so some progress was made. When it came time to install and degree the cam it was discovered that it had been ground for mechanical lifters instead of hydraulic.

Also I need to correct a mistake in my last post in which I stated.

Originally Posted by diceman50

As for an intercooler I will not be using one. There are several things involved in deciding whether one is needed or not including C/R, engine size and type, cylinder head design, etc., but generally speaking an intercooler is not considered necessary if boost is limited to 9 or 10 psi. Well below the capabilities of a McCullough.

Obviously the last sentence should have been. "Well above the capabilities of a McCullough"

[Advanced Design]

Dumb question for my learning...how were you able to tell the cam was ground for mechanical lifters? Guessing the shape or timing of the ramp?

Thanks for taking the time to share your knowledge.

[diceman50]

Originally Posted by Advanced Design

Dumb question for my learning...how were you able to tell the cam was ground for mechanical lifters? Guessing the shape or timing of the ramp?

Thanks for taking the time to share your knowledge.

There are no dumb questions, but there are a lot of dumb answers.

My friend Pete who did the machine work on my engine is an expert in matching components for an engine. The most expensive go fast parts in the world won't make any power if they don't work together. Pete looks at the engine as a whole and the purpose of the engine and picks a cam profile that is compatible with same. He has most of his performance cams custom ground and being someone who takes nothing for granted he checks them for accuracy. By putting the cam between centers and using a dial indicator he can plot the profile and compare it to what he ordered. The differences in mechanical and hydraulic flat tappet cam profiles are subtle and this is the only way to tell as far as I know.

[diceman50]

Because of an improperly ground shaft, lost shipments , and defective a defective core I am still waiting for my camshaft. So, I decided to work on the supercharger mount in the mean time. Following are some pictures of the process so far.

[diceman50]

More pictures.

[crossfire84]

nice work.

[Advanced Design]

Very nice work. You make it look easy. So, all the holes around the perimeter of the supercharger exist for mounting options?

[diceman50]

Thanks A/D,

Yes, that is correct. They also allow you to clock the output to any position.

[RockinKees]

Good looking!!

Very nice if you have the tools to make it!

[Purcell69]

This is a very cool build! I was going to use a Jeep 4.0 inline in my build, since I had a complete running donor vehicle, but the wife talked me into using the 360 V8 from the donor Dodge. I think what you've got going is a nice change from all the SBC stuff.

-Joe

[diceman50]

I ordered some velocity stacks for my blower plenum today. I have been trying to decide whether to do a common plenum or use a "Y" in the outlet and run individual hoses to the throttle bodies. I decided to do a common plenum. Also some pictures of the air cleaner and blower inlet hose.

[OutlawDrifter]

Great work, I just read through the thread. This looks like a lot of fun! Should be torquey when finished.

[diceman50]

I worked on the plenum for the supercharger some last week. I just need to finish welding it up. Following is a Photo bucket album of the fabrication so far. If you have any questions please let me know.

http://s532.photobucket.com/user/dic.../Hank%20Plenum

[Advanced Design]

Nice work. Are the velocity stacks attached or welded to the base? Are you positioning them here?
http://i532.photobucket.com/albums/e...Plenum/p12.jpg

[diceman50]

Thanks AD,

Yes I was testing the fit and they will be welded underneath. I have added more pictures to the album.

http://i532.photobucket.com/albums/e...031_120757.jpg