Thread: Supercharger advice needed

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Ok, with my Healey project winding down soon (hopefully), like any good hot rodder, I'm planning my next project. For that I plan to do limited make over on my 46 Ford coupe. There are things that need to be repaired and other things that I have never really been satisfied with. They just weren't bad enough to change.

The car originally had a 383 stroker, but the cooling system has always been marginal and that engine was overheated and damaged. I replaced it with a pretty much bone stock smog era 350 and have been driving the car like that for about 7 years. In short, it does everything a "normal" person would want. I runs good, gets decent mileage ( for a smog 350) and is as reliable as a steel handled hammer. It just doesn't have any power. The car weighs almost 2 tons with me and 1/2 tank of gas. It does have a "poor man's" overdrive (2.75 gears) and that kills a lot of get up and go.

I have recently acquired a fairly low mileage 383 with a bad wrist pin. That will be going in the car along with some kind of overdrive. I'm kinda leaning toward a TKO 600 5-speed even though it has an automatic now. I also plan to upgrade the 9" rear to 3.50 or 3.70 gears and posi. Tires are 29".

So here's where I need info. I would really like to put a small blower on the new engine. I've never ran one nor do I know anyone locally to ask, but think they are very cool. They look good and make great power. Since the engine is apart and will need some internal parts, I can build a it pretty much any way I need to.

I think the Blower Shop has a 4-71 type setup with a single carb. It uses a cog belt. I think I would like to do a throttle body injection unit on top. I want it all to fit under the hood. I'm looking for low end grunt, not a top end charge. I would also like it to run on pump gas since I drive the car on long trips. Is this possible using boost retard?

The 383 has Edelbrock RPM aluminum heads (cc unknown right now). I will zero deck the block for a tight quench. I'm thinking 8.0 to 9.0 compression, mild cam and let the blower do the work. Definitely forged pistons.

I also plan to get rid of the smallish vertical flow radiator and rebuild the inner fenders to allow a larger cross-flow unit. I know a blown engine will tend to run hotter.

What else would I need? Can I drive long it distance reliably (Power tour type trips)? I know fuel mileage will be bad, but it's a limited use car (maybe 5000 miles per year). This is strictly a thought problem right now. It will be be at least a year before I could dive into it. Any advice will be appreciated.

As I am sure you are already aware - compression ratio and pounds of boost will be critical, are you thinking of a roots style or more like a paxton style blower? When I was building my coupe engine I was thinking of using a small B&M blower, was told that 9.0 CR with less than 10 pounds boost would be fine ( and fun) , but I really have no practical experience doing this.

Yeah, I want a roots style. From what I understand, a roots will give good boost at low RPM.

I've always wanted a forced induction engine. I'm getting older and figure if I'm ever going to do it, it had better be now.

I have a good bit of clearance between the hood and top of the engine. The Blower Shop has a 192 CI blower that can be fitted with a traditional toothed belt. The traditional drive is something I think I want. It is only 8 1/2" tall. With a low profile EFI throttle body, I think it will fit. If I could find an old 4-71 setup, even used, that would probably work too.

Two of my main concerns are making it pump gas friendly and how will it hold up to long distance trips. I know the 4-71 would hold up since they were originally on industrial diesels.

Getting good gas can be an issue in some areas. I may look into water/methanol injection. I suppose I could just carry some Race Gas additive for emergency fillup situations, but would rather not need it. Water/meth and/or boost retard might get me through times when 89 octane may be all that is available. Something like an MSD boost retard would let me easily dial in more retard if needed. I might even be able to do that through the EFI.

It's all just a plan right now, but something I would really like to make happen. I want to get educated as to what works and what I need to make it work.

Got it! And I'd agree with you. If you want to do it, sooner than later will be better. Spark retard will be a key to add some flexibility and also consider Aluminum Heads, they can usually tolerate more compression with out pre-ignition or knocking due to lower quality fuel availability. And an EFI "carb" with ignition and trans control could put you in the sweet spot. Added costs but adds to the enjoyment of driving it and not tuning it on the side of the road. imho.

“…..When I was building my coupe engine I was thinking of using a small B&M blower, was told that 9.0 CR with less than 10 pounds boost would be fine ( and fun)……”


I did one of those for a customer years ago, realistically I think the actual static compression for probably about 8.5:1. It did good and really woke up the little 355 SBC. It was also pump gas friendly, but keep in mind the car lived most of its life at 4500 ft and when he took it to the strip he raced at 2000 ft……. we can get by with a little more compression and timing here.


“…….Getting good gas can be an issue in some areas. I may look into water/methanol injection. I suppose I could just carry some Race Gas additive for emergency fillup situations, but would rather not need it. Water/meth and/or boost retard might get me through times when 89 octane may be all that is available…..”

I think your right about the gas Mike, and I think it’s going to get worse in the near term with the approval of E15. On my trip back to Illinois last year there were a couple places (2 in a row) where the only option was 89 octane, either non-ethanol or E10. The old HEMI was NOT happy. If I ever make the trip again I will definitely have a couple of bottles of octane boost with me.


I think Mike is right about fuel injection and spark control, however I’m not sure the add-on spark control can automatically compensates for fuel quality. At least you should be able to change total timing pretty easily from the drivers seat however. I’m still trying to figure this stuff out myself so take that with a gain of salt.



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