Visit our Twitter feed for more great content
MGExp

MG Midget Forum

DIY supercharger option - with EFI!!!

Moss Motors
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Here are the dimensions and materials call-out for the front mount's flat component, and dimensions for the strut--which I made out of 1/8" steel I had laying around. On the strut, the hole size is unimportant; it's the center-to-center dimension that matters. I had to drill out my alternator's adjustment bolt hole, so just used a oversized bolt I had in the jar. The upper/outer end is 9/16", and on the lower/inner end, most folks will use whatever size their alternator adjustment bolt is in the casting's ear.

Probably the easiest method is to bolt on the front mount's cantilever/angle iron, then bolt on the lower end of the strut, and finally position the upper/outboard end on the front engine mount, clamp, and drill.

Also, I've included a 'before and after' of plasma cut front mounts and one of them ground smooth and with edges broken. These sets will go out in a few days to some of the 'early birds.'

Tomorrow or Wednesday I'll post the dimensions for the angle iron portion of the front mount. I'll do the same for the three parts that make up the rear mount, then we'll ask Tyler to make up CAD downloadable drawings.

Joel



Edited 3 time(s). Last edit at 2019-03-04 09:00 PM by Yankeedriver.


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
front_mount_dimensions.jpg    28.6 KB
front_mount_dimensions.jpg

front_mount_materials.jpg    55.1 KB
Sign In or Register to view this photo
front_mounts.jpg    20.1 KB
Sign In or Register to view this photo
IMG_3051.jpg    56.7 KB
Sign In or Register to view this photo
IMG_3052.jpg    58.1 KB
Sign In or Register to view this photo
Was this post helpful or interesting?
Yes No Thank
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
FYI - here is the only source I could readily find for the 8-1/2" long, 5/16-18 stainless bolt that's long enough to pass through the rear supercharger mount, accommodate the alternator/generator (whichever you have), and also pass through the water pump's mounting ear with enough left over for the spacer and idler pulley: Bolt Depot - 5/16-18 x 8-1/2" stainless. (They have them even longer.) It's pricey, but I find it really nice to have your charging unit lined up and solid without fiddling about with two bolts, nuts, etc.

The only idler you should need (pictured in Post # 658 above) is: Dayco no. 89535 (54mm dia. x 30mm wide) - cheapest I found was $20.79 at RockAuto. I believe that I listed the source for the bushing needed to mount this and other idlers on a 3/8" bolt in an earlier post, but I've got a bunch of the bushes so will send them out with M45 adapters gratis. (If you've already bought an M45 adapter, just let me know and I'll send one out.) This bolt is of course 5/16" but because of the combined width of the idler's bearing and bushing, the slop doesn't manifest once the long bolt is tightened down; the washer cinches the bearing's inner race and the whole shebang is immovable. Thus, the only dimension it could move is laterally (a scant 1/6"winking smiley, and due to the belt's tension that'd be away from the water pump pulley - a good thing.

The spacers are Hillman Group no. 58597 'Thick Heavy Duty Spacer,' 3/8 x 3/4 x 1-Inch, 5-Pack. You just cut one to the desired length, and of course make sure that the cut is square, or else the idler will contact the belt at an angle and try to push it off (it'll fail in that endeavor but will wear the belt prematurely by side-loading the mini v-grooves).

I squared the end on my big disc sander as my band saw wandered a tad, but another way to get a perfectly square cut with ordinary tools is put the spacer on a 3/8" bolt or all-thread with bolts tight on either side, then put the bolt in a drill. You then put the drill in a vise (gently) or if no vise (buy one - 6" at least!), clamp it between two 2x4 chunks clamped to a work surface, and then just lower a hack saw blade onto the spinning spacer. High speed, low pressure with the blade--and make sure you've got the rotation right vis-a-vis the saw blade's teeth, or you'll be there a while!

You'll use another of the spacers to take up the unthreaded portion of the longer head bolt you need to swap out for the standard shorty head bolt that holds the front mount's cantilever in place just aft of the thermo housing. Heck, these things are really handy, so you won't regret having a handful around.

Of course, all of this will be covered in the online instructions; this is for those whose projects are already underway.

Joel


Member Services:
Innovative DIY performance and reliability upgrades.
Was this post helpful or interesting?
Yes No Thank
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
*Note on carburetors:

I had earlier posted the link to John Campbell's DIY article on this forum about blowing through an SU carburetor - but here it is again: How to Blow Through an SU

Now, some people use a thin gasket on the vacuum chamber for the damper - assuming you haven't sprung for an obscenely expensive Metro-specific HIF44. This is what Campbell recommends. That may be fine, as we're only talking 5~8 lbs of boost for most folks doing this conversion. I'll certainly experiment with this--probably after the 'early birds' who appear poised to have their cars running in advance of my '67 test mule.

However, my neighborhood machinist pointed out the (again, obscenely expensive) O-ring cutters used by some high-performance engine builders on cylinder heads. The range of these devices is sadly too large for our application--even if the high cost weren't prohibitive.

That said, it occurs to me that given the soft material used in the damper chamber might lend itself to a relatively simple grooving jig using an inexpensive circle cutter's carbide bit (I use such a jig for woodworking). I'll experiment and see what I can come up with. It'd be cool if there's an existing O-ring with a thin enough wall thickness and right diameter to nestle into a teensy groove--well, either in the damper housing or the carb body itself. Both pieces have a nice indexing bore smack in the center--the piston's sleeve in the damper, and the jet's well in the carb body. So, retrofitting a regular HIF44 with a damper O-ring may be possible... and that would be a really nice piece of kit, as Johnny would say!

Joel


Member Services:
Innovative DIY performance and reliability upgrades.
Was this post helpful or interesting?
Yes No Thank
mrmg1965 Avatar
mrmg1965 Gold Member Steve Strublic
Peoria, AZ, USA   USA
1965 MG Midget "Gidget"
2011 Mini Cooper S "Nigel Whitworth"
Joel, that looks really good. Like 'factory' if there were such a thing. I think you hit on the right answer.

Making me itchy for a project...

Steve



http://midget.strublic.net

. Hide this ad & support a small business by becoming a Gold Supporting Member
Was this post helpful or interesting?
Yes No Thank
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3903487 by mrmg1965 Joel, that looks really good. Like 'factory' if there were such a thing. I think you hit on the right answer.

Making me itchy for a project...

Steve

Steve,

Thanks very much. Indeed, the more enjoyable part of the project, now that I've finally arrived at a viable mounting system, will be developing tidy plumbing for the intercooler, bypass, and air cleaner circuits, to produce the cleanest possible 'super stock' aesthetic under the bonnet.

But to me, this is the really fun part, where Spridget DIYers can readily exercise their creativity, as it involves selecting and moving around various silicone snorkels, connector pipes, and experimenting with air cleaner locations and configurations. In short, the exercise promises hours of sitting with the bonnet open, sipping your favorite beverage, and pondering the best design for one's little British hot rod.

The one limiting factor is the bypass circuit--something that I highly recommend, but which some may elect not include on their setups. I had initially laid out the bypass plumbing using the Hitachi (Subaru Loyale) throttle body I hope to ultimately run, but so far all of the 'early birds' will be running the SU HIF44. I will do that as well for the first several months of operating the new engine.

The solution I've been envisioning is a bypass circuit that dips below the carb rather than over the throttle body, due to the obstruction caused by the HIF44's vacuum chamber. A simple mandrel bent mild steel pipe made up by my local exhaust guy would be easiest for folks to replicate--and I'd then make a simple heat shield to keep the header from heating the air shunted over from the air cleaner tract on trailing throttle and steady-state cruising. But I can't wait to see what others think of!

Oh! I was watching a British murder mystery last night, and the evil doctor drove a DB5. Well, that car has open ports on the fenders--though I assume to let heat out rather than air in. Well, one idea for a cool air intake that has repeatedly entered my mind is either a DB5-esque port or an NACA-style duct, which would let into a sheet metal box isolating the air filter placed in the same location mine is now (see first pic).

The same kind of box could, of course, be fed by my existing 'stealth' intake (second and third pics). That's the existing plan. But it'd be cool to have the blower hungrily sucking cool air through an open port just ahead of the (U.S.) driver's window! Or one could do a vertically vented box with the NACA duct let into the bonnet, and which sealed upon closing with a rubber gasket. If I had Adrian's sheet metal-working prowess, I'd likely go for it!

As for your hankerings, by all means, feel free to join the fun!

Joel


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
air cleaner clearance.jpg    46 KB
air cleaner clearance.jpg

cool air intake, fender well.jpg    47.2 KB
Sign In or Register to view this photo
Intercooler installation (9).jpg    37.7 KB
Sign In or Register to view this photo
Was this post helpful or interesting?
Yes No Thank
mrmg1965 Avatar
mrmg1965 Gold Member Steve Strublic
Peoria, AZ, USA   USA
1965 MG Midget "Gidget"
2011 Mini Cooper S "Nigel Whitworth"
Joel,

You gotta do it. You need a scoop that feeds the beast.

Steve



http://midget.strublic.net

Was this post helpful or interesting?
Yes No Thank
gadams Silver Member Gerry Adams
Lincoln, Nebraska, USA   USA
Joel,
First time I have heard you mention the Hitachi carb. When it comes to larger carbs (>1 1/2”) i have a pair of snowmobile Hitachis and Strombergs, and so delayed ordering the new HIF. Please don’t hesitate posting any creative Hitachi setups you are considering when you are toying with that carb!

. Hide this ad & support a small business by becoming a Gold Supporting Member
Was this post helpful or interesting?
Yes No Thank
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3904398 by gadams Joel,
First time I have heard you mention the Hitachi carb. When it comes to larger carbs (>1 1/2”) i have a pair of snowmobile Hitachis and Strombergs, and so delayed ordering the new HIF. Please don’t hesitate posting any creative Hitachi setups you are considering when you are toying with that carb!

Gerry - sorry for the confusion, but it's a throttle body, not a carburetor, that I harvested from the '90s Subaru Loyale. It is for the DIY EFI project, which I hope to run under boost once I break in the engine and finish the beta testing with the SU HIF44. See attached pic. It has a boost/vacuum reference port that in the OEM configuration connected to the fuel pressure regulator. I'd have to experiment in our situation, as the port is on the intake side of the butterfly rather than the manifold side.

It's hard to see, but the giveaway is the two smaller vacuum hoses crisscrossing above the blue snorkel from the air cleaner attach to the idle air control valve, bolted to the brake pedal box--and if you look really closely, you can see the throttle position sensor on the rear of the throttle body.

Anyway, carbureted cars will have less cluttered plumbing, as discussed above.

In fact, now that I am thinking about the intake plumbing again, ideal would be a welded aluminum elbow (3" as that's the size of the flange on the HIF44 adapter I designed for this setup, second pic), to replace the fat silicone elbow shown here coming from the intercooler. It would have a 1" hose barb to receive the corresponding barbed side of the Mini bypass valve, which bolts directly to the existing, inexpensive aluminum snorkel adapter--which arrangement is immediately above the vacuum hoses to/from the idle air control valve in this pic.

That would do two things: (i) eliminate the bypass hose traveling over or beneath the carb (or throttle body), thus making a much less cluttered bay; and (ii) create an extremely short bypass circuit. Most of us wouldn't notice any difference in responsiveness of the bypass function this might produce, but it's at least conceivable that racers snapping the throttle off and on when negotiating esses might benefit from ultra fast actuation.

My neighborhood CNC shop owner said he has an outstanding aluminum welder who is quite reasonable, so if I'm unable to source something existing that would fit the bill or create reasonably attractive welds on such a piece (my Hobart will weld aluminum), I'll call the guy to discuss. But it should be really cheap, as we're just talking welding a 1" nipple to a 3" pipe, after I'd done the fitting. Either way, I'll be happy to provide this piece cheaply if viable.

That said, you should feel free to experiment with whatever carb you like. I would just ask that you email me results, so I can incorporate any viable options in the online instructions for other people to consider. I've already built the general info page for the conversion, and it includes a place for a table to post people's engine mods, differing configurations, tuning data, and boost figures. (Just need to figure out how to make a table render properly across various platforms.)

Joel


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
intake plumbing(1).jpg    57.2 KB
intake plumbing(1).jpg

Creative Spridgets HIF44 snorkel adapter, ram pipe.jpg    40.1 KB
Sign In or Register to view this photo
Was this post helpful or interesting?
Yes No Thank
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3904080 by mrmg1965 Joel,

You gotta do it. You need a scoop that feeds the beast.

Steve

Yeah, might have to. I'm likely going to go with the existing setup initially, as I don't want to slow down startup beyond rebuilding my engine (which is about to happen!). But my head was swimming with cool, understated options for an integrated, NACA-vented air cleaner isolation box last night. Those people with sheet metal and paint skills are going to come up with something way cool on this front. What fun! smiling bouncing smiley

Joel


Member Services:
Innovative DIY performance and reliability upgrades.
Was this post helpful or interesting?
Yes No Thank
1974MGMidget Avatar
1974MGMidget Silver Member Jack Orkin
Grayson, GA, USA   USA
Joel, here's an idea for an air scoop for your Lil 'Vette -


Attachments:
1957-Chevrolet-Corvette-C1-Fender-Mounted-air-scoops-IMG_0470_a.jpg    32.2 KB
1957-Chevrolet-Corvette-C1-Fender-Mounted-air-scoops-IMG_0470_a.jpg

Was this post helpful or interesting?
Yes No Thank
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3904440 by 1974MGMidget Joel, here's an idea for an air scoop for your Lil 'Vette -

Well, that's interesting, as you may recall from the DIY EFI thread that I'm planning on using the fuel injection script from the same year Corvette--just no checkered flags. See attached images...

Joel


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
Chevrolet-1957-FI-badge.jpg    25.6 KB
Chevrolet-1957-FI-badge.jpg

EFI script, rear panel.jpg    26.6 KB
Sign In or Register to view this photo
Was this post helpful or interesting?
Yes No Thank
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
And the winner is... Dayco 5050570. Other part numbers are: Bosch/Contitech 5PK1450, Delphi MR51450--but this is according to eBay. So, I'd go with the Dayco number if possible.

Fitment is snug, as in you have to walk the belt onto the water pump or blower pulley. But it's a snap to do, not one of those knuckle-skinning exercises. The next size up I could find was nearly a full inch longer and the tensioner reached the end of its arc before tightening the belt up fully. Of course, one could reinstall the second 2" idler on the front mount and preload the belt to make Continental 5050582 work just fine. But this one is great.

As you can see, the wrap is excellent on the blower and alternator, and more than adequate on the crank, and it tracks true. I put the belt on crooked on the idler, turned the crank, and it immediately moved to the middle of the idler. There's plenty of room beneath the thermo housing well in the head. No need for the extra idler after all.

Finally, because SmoothFlow's modular M45 pulley setup is 6-rib off-the-shelf, you get an extra groove. That effectively adds even more fore-aft adjustment--read that: forgiveness for people welding up their own mounts. I've now cut parts for several sets, and it's really not very difficult at all to do. I'm working on the photo series for the website instructions, and will get everything to Tyler for downloadable CAD drawings in the next few days.

In keeping with the 'super stock' theme I've chosen, I painted my set OEM green for my '67 Midget. I like the way it looks. The silver of the blower and alternator, and if I don't say so myself, the black anodized finish of the new thermo housing spacer/temp sensor mount and the M45 manifold adapter, look handsome next to the green.

Oh - the production sets I'm welding up for the 'early birds' this weekend won't have the unnecessary holes from my R&D. It's only my set that will have the Frankenstein look. spinning smiley sticking its tongue out

Now it's time to disassemble the engine to measure for machining and balancing. She'll be wailing away before long now!

Joel



Edited 1 time(s). Last edit at 2019-03-08 04:25 PM by Yankeedriver.


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
IMG_3167.jpg    38.1 KB
IMG_3167.jpg

Creative Spridgets DIY supercharger(1).jpg    52.4 KB
Sign In or Register to view this photo
belt clearance at head.jpg    38.6 KB
Sign In or Register to view this photo
Creative Spridgets DIY supercharger mounts(2).jpg    40.8 KB
Sign In or Register to view this photo
Creative Spridgets DIY supercharger mounts.jpg    52.9 KB
Sign In or Register to view this photo
Was this post helpful or interesting?
Yes No Thank
johnnyw637 Avatar
johnnyw637 Silver Member John Warner
Norwich, Norfolk, UK   GBR
1960 Morris Minor Traveller "Boris 2"
1964 MG Midget MkI "Flying Midge"
1964 MG Midget MkI
Love the BMC European spec green Joel,

Totally agree with it looking good against the other engine parts and think it works even better with the total contrast of the red bodywork.

Have you had chance to test the engine in the car yet?

It's going to be real interesting working in the field with it. Can't wait to see some video footage of it in operation.

Just need a Watneys Red Barrel (most popular British beer of 1967) keg fuel tank on the boot rack and you should be able to do that route 66 run in one hit.

Fuel injection badge looks right a perfect match
All looking wonderful

All the best Johnny

Was this post helpful or interesting?
Yes No Thank
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3905509 by johnnyw637 Love the BMC European spec green Joel,

Totally agree with it looking good against the other engine parts and think it works even better with the total contrast of the red bodywork.

Have you had chance to test the engine in the car yet?

It's going to be real interesting working in the field with it. Can't wait to see some video footage of it in operation.

Just need a Watneys Red Barrel (most popular British beer of 1967) keg fuel tank on the boot rack and you should be able to do that route 66 run in one hit.

Fuel injection badge looks right a perfect match
All looking wonderful

All the best Johnny

Johnny,

Glad you like the color scheme; I love it (though some of the 'early birds' have ordered silver mounts). On the contrast with the red bodywork, guess I'll have to actually clean my engine bay before reinstalling the power plant...

By 'test the engine' do you mean fire it up? If so, the bottom end is tired and I'm afraid to pump 100 h.p. through her before I've fitted new bearings and balanced the engine. (I'm teetering on a center strap.) If you mean test-fitted, the front mount was designed while the engine was in the car; the rear mount mirrors the 65-degree profile of the front's outer edge--which is also the cant of the blower--and I believe is just shy of the front mount's lateral protrusion toward the inner wing/fender.

So, the only clearance issue I'm anticipating is the pressure switch in the brake line union. I swapped mine out in favor of a regular three-way union, and drilled/tapped the pedal box for a late model mechanical switch. That said, I suppose that I should slip the engine back in before welding up the mount sets for the 'early birds' to rule out that issue or give them a sense of another small task they'll have to tackle to complete the conversion. (If one doesn't want a mechanical switch, worst case scenario is simply moving the union aft/down a touch.) The ignition coil definitely has to move, as it contacts the underside of the blower's curving inlet cavity--but that's a 10-minute job. The GM ignition module attaches to the OEM coil mount for my DIY EFI setup.

Turns out my neighbor's son has a drone, so I'm going to ask whether it has video capability. Even if not, I'll definitely shoot some videos for the website, including a walk around with engine bay tour, cockpit showing gauges while running including boost/vacuum gauge (likely on the steering wheel column w/custom, low-profile aluminum mount), and some action footage taken on the roads in the high desert and mountains hereabouts. Attached is a slightly different angle of my avatar shot, showing the mid-level elevations; the blacktop up the back of the Sandias goes through dense conifer forests.

Hah! I love the vision of that keg strapped to the boot lid. Hilarious! Though, I'm afraid that orange would clash with my shade of red...

Joel


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
Joel's Midget, high desert.jpg    62 KB
Joel's Midget, high desert.jpg

Watneys keg.jpg    9.2 KB
Sign In or Register to view this photo
Was this post helpful or interesting?
Yes No Thank
johnnyw637 Avatar
johnnyw637 Silver Member John Warner
Norwich, Norfolk, UK   GBR
1960 Morris Minor Traveller "Boris 2"
1964 MG Midget MkI "Flying Midge"
1964 MG Midget MkI
You are right Joel,

The Watneys Red Barrel just won't suit the paintwork... Just not classy enough smiling smiley
Type face all wrong too smiling smiley

As for the test I had meant road rather than bench...I very much look forward to seeing the former.

Johnny

Was this post helpful or interesting?
Yes No Thank
. Hide this ad & support a small business by becoming a Gold Supporting Member

To add your reply, or post your own questions




Registration is FREE and takes less than a minute!


Having trouble posting or changing forum settings?
Read the Forum Help (FAQ) or contact the webmaster