Mrgadget

Well, I finally got it done. Had a shop bore the the 1970 small block with #6 heads, port the heads and supply pistons, was supposed be 9:1, well engine ran fine but I wanted more power.
So I was thinking supercharger, after reading on this site, it looked tough to do or nearly impossible to get it under the hood, I was not cutting the hood.
So being a retired engineer, I set out to see if a Weiand 142 with a modified manifold would clear. I purchased a used Offenhauser 5822 single quad manifold for $150, if this didn't clear, it was coming off and I would sell the hardware and go to a built 455.
I cut open the manifold and had a friend machine it out to my dimensions, I used a 3/8" aluminum plate, for the Weiand 142, and had a guy heliarc it on, after the stackup, I needed a very low filler neck, so I took the stock neck and cut it out at about 45 degrees and laid an 1 1/4, .125 wall pipe in it and brazed it together.
I tried a smaller air cleaner, but the SC required much more air to run smooth, so I used a 1" drop hat base for a 14" air cleaner, and cut the front off, welded a piece across the front and added an .080" plate for the top, also, had to mod the back of the drop hat to open it up for a smoother air flow( I have more pics of this), the carb is an Edelbrock 1407, 750 cfm, it was near new and came with the SC purchase from ebay which was $1600 for everything.
The crank pulley was for a SBC which has a 3 hole fastener setup, the Olds has a 4 hole, so I bough a used harmonic balancer and made a 4 hole attach pattern, when we put the crank pulley on it needed to have .200 off the back, the belt fits perfect.
It was a lot of work and fun to get a roots blower under the hood for a sleeper, I have more pics, but the hood closes with a very little clearance and it runs like it's got 400-425 hp.
I could only load 5 pics, but have more.
Mine is a 442 clone, it was a basket case when I got it 10-11 months ago.
Be glad to send more info to anyone interested.
Frank

coppercutlass

I'M in love lol. LOve the fact its an sbo and you put in the effort to get what you wanted. Love it lol. Get that thing to the track !

Kennybill

Nice job! That's the way to make a good driver and have power. Very creative. I would like to see a write up with pictures! Thanks for the post. Ken

hookem horns

Love it! Great combo of keeping it Olds powered and custom at the same time.

txrob779

Indeed good job....Hurray for you for going down the path less traveled.

cutlassefi

I have the utmost respect for guys that think outside the box, well done!!

Note; If someone decides to copy Franks efforts, you can use a Professional Products balancer. It comes with both Olds and BBC bolt patterns. It'll make it easier to get a drive pulley.

Again well done!!!

citcapp

Very cool and what a conversation piece too

Professur

I almost feel sorry for the next mustang or camaro you find. Almost.

Mrgadget

Well, thanks to all, it was truly a fun project and very rewarding..........my friend in Huntington Beach has an auto repair shop, he did all the work on engine assy, tranny(700r4) and built the rear end and the blower install. He said you can't fit it under the hood, kept wanting to cut the hole in it, but he went along with me and needless to say he loves it, he actually was the first to test it next to his shop with me in it and he broke the tires loose with posi 3.73 almost all the way down the short space he had.

oldcutlass

I bet it's a blast to drive. Awesome work.

Mrgadget

Cutlassefi, I've read a lot of your good posts, good job on solving others install problems......... I'm an "experienced novice" as what I like to say and was thinking of the EFI route it the carb direction proved to be too cumbersome.
Frank

Professur

How long did it take to powerwash the grin off his face after that?

oldsmoboogie

Excellent!

Tom442

More pictures please!!!

Mrgadget

I will post pics of some of the things I had to consider.......
The first thing was getting the plate as low as possible in the Offy manifold, my friend had to touch off at the front and back intake ports to make sure the plate was parallel to the crank before he machined downand ended up with a nice base for the plate to sit on........the plate is .375 x 6.50 x 11.50, it needs to be flush with the top of the manifold in the back, the front of the plate is about 1.25 from the front manifold bolt on the pass. side, the heliarc guy was good, he had to grind back a way from the plate along the back and weld a larger area because the manifold was machined thin. The first pass at this was a .50 thick plate with .125 above the manifold, then after much measuring, I had my friend machine .125 off the plate bringing it to .375 thick and flush with the back of the manifold.
The filler neck I made from a stock filler neck and a 1.25" pipe with .125 wall and laid it down to where it cleared the SC and it wasn't low enough after the second machining so I had to heat and dimple it a bit, should have been almost flat to clear the SC.
I know this is a little long winded but I needed every 1/8" I could get.
I'll post later about the air cleaner..........I used 3 different shots at it before I ended up with this one.
Placing the SC on the plate is critical.......left right is easy SC is same width as the plate, front of the base of SC is 1 3/8 aft of the center #1 manifold bolt on pass. side which puts the back of the SC pulley 1/8" in front of the fan pulley. This keeps the front of the SC pulley about 7/16" behind the fan shroud, I'll post a pic.

olds 307 and 403

That is so cool. I take it that blower manifold is much lower profile. Just great.

Eric Anderson

Very cool

jag1886

Now that is cool. Thank god for engineers.

johnnyjaws

u should start selling them or patent it

Mrgadget

Yes, that was a low profile manifold to start with........I needed it to be lower.
Frank

Mrgadget

I think some of the more experienced guys on this board said they made manifolds for SBO years ago but there wasn't enough call for them.
Not sure if they fit everything under the hood either.
Frank

Mrgadget

Posted some pics of this............it basically is more wording to show what had to be considered for fitting it under the hood.........the air cleaner I posted and trying to perfect had a slight stumble at high rpm and high speed.......... so I'm opening up the top with a perforated pattern and a wire mesh for protection.........still working that out..........proper air flow has been a need for this setup.
I was using the Edelbrock triangular wire mesh air cleaner, #1002 I think, but like this one better.
Frank

RetroRanger

That's really cool and shows dedication to the concept, thanks for sharing mr g I would love to see this in person someday.

Any comments on drivability say compared to a mild BBO? How about hp output ? Nice job

allyolds68

Impressive, innovative, nice, clean job.


Now put an OAI hood on it.


It doesn't have to be THAT much of a sleeper

hookem horns

May look like a sleeper but that tell-tale blower whine will give it away when running. Great problem to have. Car guys will be asking to look under the hood and youngsters in modern rides will have never heard that sound anyway. They will remember your tail lights though....

Mrgadget

Well, I'm in So. Calif, welcome anytime.
I've never driven a BBO, so can't tell for comparison, but it drives like it did before the SC, vacuum is about 10 at idle and 15 or so when driving, but just moderate pressure on the accelerator and the gauge is heading to 0 and into positive territory, max boost is 5 psi.
My mechanic friend and I think we are in the 400-425hp range by the responsiveness of the engine.
Frank