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DIY supercharger option - with EFI!!!

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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Adrian -

As for variations in belt tension, there wouldn't be any with the new 'swing arm' configuration; the small amount of engine roll would be tracked 1:1 by the mount.

I did think about fore-aft movement, and had thought of controlling it using little mild steel straps between the rack crossmember and the motor mount bolts (engine side).

That said, I think your and Trevor's preference for a rigid mount over a novel configuration is worth another redesign. I can always default to the swing arm-plus-fore/aft stabilizers if I can't make it work.

Also, the $20 in angle iron and steel plate is hardly wasted, as they do hold the blower nicely in three-dimensional space. My wrist was getting tired! Pretty cheap R&D costs. cool smiley

Perhaps the most difficult design considerations are presented by the DIY goal: low cost components vs. easy-to-make end-user components or modifications. Moving one or more front mount components knocks out several possible options, because (for instance) water-jet cutters have minimum order requirements that change the economy of scale. I'd like people to be able to make up the mounts with nothing more than a drill, files, vise and hammer.

All that said, what might work is a rear mount that supports much of the blower's weight while tying it rigidly to the block. This could be fairly straightforward, as the blower's mounting lug directly opposite the twin over-and-under rear alternator bolts is reasonably close to the blower's balance point fore/aft. That mount could simply be a short piece of 3" wide steel plate bent into an 'L' whose short leg gets two holes for the over-and-under rear alternator bolts (longer ones, to make full use of the threads). The outboard end would get a little piece bolted on which, in turn, accepts a bolt passed through the blower's mounting lug.

As for the more difficult front mount, perhaps I could use a single, long alternator mounting bolt (or even all thread) in place of two shorter bolts. That would afford an attachment point for connection to the tops of the front mounting lugs I currently tap from below. I've got to think about either tying the unclocked alternator into that upper plate, or returning it to a clocked position and coming up with a vertical connection for the front of the blower--if that's necessary, depending on how rigid the rear mount I've described turns out to be.

Okay, I'll fab up the rear mount and we'll see what develops! Who knows, it may surprise me with its rigidity, as did the present front mount, thus simplifying what's needed for the front.

Joel


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Denis Avatar
Denis Denis Hill
Bearii, Nth Victoria, Australia   AUS
Alignment is more critical with a multi groove belt . When its right and solid there great but if not they don't need much of a reason to jump. Denis



68 B roadster, Daffodil yellow, supercharger, Burgess SC head, SC cam, Mikuni HSR 48 carburetor and engine built for supercharging.

73 BGT V8 conversion starting with a bare shell. Built the engine early in 2016 with high comp pistons and a few other nice bits. Started on the body late 2016 and found Its a lot of work and expense starting from scratch. Did the work myself, mechanical, body. paint etc all except the interior trim.
Finished and going well, great to drive and quick. Now has a nice 3.07 LSD.

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pinkyponk Avatar
pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
Not sure if this is helpful but it's an A series and it has a supercharger mounted to it.

Adrian



Home built Eaton M62 Supercharger with 9psi boost, "stock" high ratio rocker arms, 8:1 compression, Piper 270 cam, ported head, matched manifolds, CB Performance computerized ignition.


Attachments:
mini with blower.jpg    42.8 KB
mini with blower.jpg

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Denis - absolutely, we want boringly reliable belt tracking--coupled with breathtaking, budget-slashing boost, of course. smileys with beer

Adrian - the picture is very helpful, thank you. Any suggestions for how to skin this cat are welcome.

I see that she's sporting a late model Mini Cooper S blower, which unfortunately won't work on the Spridget due to distributor and oil filter interference when lowered sufficiently to clear the bonnet. But I know you realize that and posted the photo for design inspiration. It worked, as I fell asleep thinking about heim joints, levers, and plate configurations (oh, my!).

One thought I briefly entertained as I drifted off was losing the distributor in favor of solid state ignition, going with a remote oil filter, and thus enabling placement of the blower below a slightly raised alternator (merely rotated out/up on its existing mounts), as this M45 was mounted in the Mercedes whence it came. I do already have a 4-rib serpentine crank pulley design with a provision for a built-in ignition trigger that was bid out very favorably. That would be cool and make the mounts very short and simple.

However, the vast majority of people seem interested in retaining the distributor over a crank-fired ignition, and this blower is ideal for that, as its curving inlet gallery leaves lots of room to access the distributor and starter/selenoid, for that matter.

Also, after looking at the photo you provided last night and braving the cold shop to stare at the engine this morning, a possible solution occurs to me. First (and regardless), I'll make the simple rear mount described above in post no. 391, and which will handily bear much of the blower's weight. The tab for attachment to the blower's rear/inner mounting lug--which is closer to the center of the mass fore/aft than its outboard partner (see attached photo)--will have a slotted hole for belt alignment fore/aft along the long axis. Of course, that hole will also act as pivot for alignment adjustments in the perpendicular plane. Then, the front mount becomes more about diagonal or lateral bracing, and inboard/outboard and alignment adjustments.

In view of all that, the new photo combined with the earlier one you posted with the Aisin blower suggest a few options. I would greatly appreciate feedback on these, as I think they're viable, and any other ideas. Please remember that, ideally, the mounts would be user-fabricated without welding--but that's the chief difficulty right now.

Option one (inspired by the Aisin setup), has two components: an 'h-shaped' mount with the twin legs of the 'h' affixed to the forward head bolts, and the single outboard arm extension extension attached to a simple, machined aluminum block or bent steel 'U' mount bolted to the top of the blower's front mounting lugs. Then, a simple strap ties the blower to the alternator's third mounting lug and to the engine-side of the motor mount 'wing' of the front engine plate.

Option two would use the same vertical alternator-blower connection, but would replace the 'h' mount bolted to the head with a sleeve on a single, long alternator bolt welded to an arm that reaches out to the blower's front lugs.

Option one would be much nicer for people if I had the 'h' water-jetted, and a simple shape like that is not prohibitively expensive if I can talk that shop's foreman into not gouging me for a short run. Option two would require welding the sleeve to the steel bar arm, but another neighbor (retired pipe fitter and Harley rider) says he'll let me use his welder for the prototype, and I've been wanting a welder for years anyway. This might be the time to break down and get one.

So: any thoughts on problems associated with bolting the 'h' mount to a couple of head bolts, as in the Aisin video? It would essentially replace the flat washer, I suppose, or necessitate a thinner washer...?

Joel


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Attachments:
Creative Spridgets supercharger adapter(1).jpg    47 KB
Creative Spridgets supercharger adapter(1).jpg

pinkyponk Avatar
pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
How hard would it be to put the alternator on the other side of the engine and put the supercharger in it's place? A bracket or 2 and a mini wire harness? There has to be room... Moss got a whole supercharger in there

I keep thinking a custom front engine plate would solve some issues and look the business... but I doubt people will want to got to that much bother. (swapping front plates, I mean)

I also see that you could tap some holes into the side of your black SC adapter and bolt brackets to it for minimal machining costs.

Adrian



Home built Eaton M62 Supercharger with 9psi boost, "stock" high ratio rocker arms, 8:1 compression, Piper 270 cam, ported head, matched manifolds, CB Performance computerized ignition.

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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Hi, Adrian. Let me address these suggestions in turn (thank you):

"How hard would it be to put the alternator on the other side of the engine and put the supercharger in it's place? A bracket or 2 and a mini wire harness? There has to be room... Moss got a whole supercharger in there."

- I never thought of that. Very creative idea--and if feasible, that would make the blower mounts very straightforward and easily made by the average shade tree mechanic DIYer. Let me look into it--though it'll have to wait until after Christmas/family stuff. Cool.

"I keep thinking a custom front engine plate would solve some issues and look the business... but I doubt people will want to got to that much bother. (swapping front plates, I mean)"

- I agree that would be great, but expensive, and I also agree that most folks want to do as little intrusive stuff as possible. Lifting the engine a bit to R&R the crank pulley and the other steps involved in the Moss installation are about where I want to stop, too.

"I also see that you could tap some holes into the side of your black SC adapter and bolt brackets to it for minimal machining costs."

- I'd rather not do that, primarily because of the care I had the machinist take in doing a surfacing/flatness pass as the final routine in making the part (other than breaking the edges, obviously). I don't want stress transferred through the adapter to disturb the seal between it and the blower. Also, I think the four existing mounting lugs will be sufficient.

I'll make the rear mount after Christmas, look at the moving the alternator, and see where we are.

This is great stuff, please keep it coming!

Joel



Edited 1 time(s). Last edit at 2017-12-20 07:10 PM by Yankeedriver.


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Okay, I believe I've got the front mount licked. Thanks to all for the feedback. The design ends up being fairly simple but will require me to either weld up a steel unipart or CNC machine the central component (or both components) of a bolt-together mount.

Neither of those options will increase the cost of conversion excessively, but I'm leaning toward the latter, as one or both components could be machined out of 6061-T6 bar in a single setup on the big CNC mill, or the 'little' one they just bought (merely the size of a minivan).

Bonus - I discovered that the Chevy Avalanche tensioner slips right onto the long, single bolt (replaced in the photo in post 379 by a big Phillips screwdriver), precisely lining up with the Saturn alternator's stock pulley, and its second mounting lug would bolt straight to the vertical surface of the new mount. I realize that between the crank and blower is more ideal, as Denis pointed out, but I think it'll work fine immediately after the blower--and it's right in front of you when popping open the bonnet, making belt replacement literally a 2-minute affair. R&Ring the alternator or the water pump will be quicker than with the OEM v-belt setup, too.

The solution:

I did some sketches and math aimed to determine how much force would be exerted on attachment points by various configurations, and it occurred to me that the simplest way to achieve what the guy was trying to do in the Mini setup is to use a head attachment more like the Aisin setup--preferably two bolts. That leaves two choices: use the forward two cylinder head bolts, as with the Aisin setup, or use the thermostat housing bolts.

I like the latter because people wouldn't have to fret about loosening two head bolts, whether they'd have to reseal the entire head, etc. The bolts are smaller, but the design I came up with negates that concern in two ways.

First, because different years seem to have thermo housings that are of varying height, I realized it's better to make the part's horizontal member a flat plate that goes between the head and the housing. Its upper surface will have the same step to accommodate the thermostat and facilitate sealing. I could include an O-ring groove on the upper surface to supersede the OEM gasket, but doing so on the head side means two setups and destroys the price point. So, it'll probably have an O-ring where it mates with the thermo housing, and use a standard OEM gasket against the head.

Anyway, this design transforms 100% of the force exerted on the thermo bolts into sheer exerted right where they emerge from the head--extremely strong, even with regular grade bolts. Also, the potential twisting force exerted on the head is virtually nil that close to its long axis.

Second, the design employs cantilevered bracing to distribute the overwhelming amount of the force exerted by the blower's weight and belt tension against the flat side of the head, so the amount of sheer on the thermostat bolts is much lower than that exerted on the heim joint used in the Mini setup (which is far too Rube Goldberg for my taste, even if it had fit under the sloping Spridget bonnet).

Finally, the Saturn alternator does get 'clocked' after all (or people can just put a ribbed pulley on a late model Spridget Lucas alternator), and the third mounting lug gets a 1" version of the turnbuckle I posted earlier, or a simple flat steel strap that can be made up by end users in 10 minutes with a drill, hacksaw, and file. If a person wanted to go with a teensy, high-boost pulley, all they'd have to do is adjust the turnbuckle, or if using the strap make a slightly longer one to take up any resulting slack in the belt--or buy a slightly shorter belt, of course, per my earlier post with the link to the length-search webpage.

So: when I get a free weekend morning, I'll make the prototype, bolt it together, and if all looks good, I'll go talk to the shop foreman--who's supposed to have a bid on the HIF44 snorkel adapter any day now. But even if it isn't as cheap as I anticipate due to the short run economics, I may just opt for welded steel and make them myself. After all, there will only be 10 kits--oh sorry, 9 kits, as one of the supercharger adapters has already sold to a UK racer for an open-class A-series-powered car he's building. The adapter j-u-s-t fits into the same flat-rate box as the brake adapters, so international shipping is very reasonable!

Joel



Edited 2 time(s). Last edit at 2017-12-21 03:13 PM by Yankeedriver.


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pinkyponk Avatar
pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
Sounds like a a plan. The Aisin setup used long nuts to eliminate loosening the head when servicing the blower. These are from the MGB so they are proper hardened nuts. Here is a thread describing them. http://www.mgexp.com/phorum/read.php?1,3047881

Might come in handy on your build.

Adrian



Home built Eaton M62 Supercharger with 9psi boost, "stock" high ratio rocker arms, 8:1 compression, Piper 270 cam, ported head, matched manifolds, CB Performance computerized ignition.


Attachments:
Long head nut.jpg    29.4 KB
Long head nut.jpg

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3649356 by pinkyponk Sounds like a a plan. The Aisin setup used long nuts to eliminate loosening the head when servicing the blower. These are from the MGB so they are proper hardened nuts. Here is a thread describing them. http://www.mgexp.com/phorum/read.php?1,3047881

Might come in handy on your build.

Adrian

Cool, I'll check it out. Thanks.

Joel


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pinkyponk Avatar
pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
As promised... pics of my AMR500 strategically balanced in my Bugeye engine bay. Bags of room.

Just need a piece of box section aluminum to bolt to the stock intake manifold for a plenum/blower mount and some tubes to mount a carb and air filter... should be a piece of cake. Oh and a crank pulley. Shouldn't be too hard to fab up something using a water pump pulley off some modern car.

Adrian



Home built Eaton M62 Supercharger with 9psi boost, "stock" high ratio rocker arms, 8:1 compression, Piper 270 cam, ported head, matched manifolds, CB Performance computerized ignition.


Attachments:
Aisin 001.JPG    47.3 KB
Aisin 001.JPG

Aisin 003.JPG    57.4 KB
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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3649497 by pinkyponk As promised... pics of my AMR500 strategically balanced in my Bugeye engine bay. Bags of room.

Just need a piece of box section aluminum to bolt to the stock intake manifold for a plenum/blower mount and some tubes to mount a carb and air filter... should be a piece of cake. Oh and a crank pulley. Shouldn't be too hard to fab up something using a water pump pulley off some modern car.

Adrian

Pretty neat, Adrian. Will yours be a draw-through setup, then?

Please let us know what you come up with by way of a DIY crank pulley. I couldn't figure out an existing production car/wrecking yard option.

I'm eager to see your 'blown bugeye' up and running!

Joel


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Well, I'm going to have to go with those long nuts after all. I am reminded by Adrian's photos that my car once had the vertical flow radiator, and I think the mount I was looking at making up would interfere with the upper hose. I'll have to dig out the old thermo housing and make sure, but it's looking like it.

I think those nuts will be plenty strong, however, since we're just talking a little sheer force with the brunt of the weight exerted downward.

Hope Moss still stocks them!

Joel


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Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Two updates:

1) Turns out, there are no problems with the front mount design, as suggested in last post. The simple solution is to use the later model, cross-flow thermostat housing but rotated to aim toward the right-hand side and angling forward. This may not allow room for the plastic fan, but the Avalanche tensioner will likely interfere with that anyway, so I'll recommend going electric as I did a while back. In the alternative, you just put a slight two-bend jog in the plate to make room for the stock thermo housing and go with an old-school sliding belt tensioner. As I've said, my 1998 Subaru had one and never spun a bearing on an alternator in 270,000 miles.

I'll post a sketch or just show the finished mount this weekend, if time permits.

2) Attached is a sketch of the rear mount, made en route to visit the OKC in-laws for Christmas. The angle of the big bend on the supercharger end is done from memory, so I'll finalize that and post with a DIY photo series this weekend. As I've said, it attaches to the ear directly opposite the twin alternator mount bolts, right in front of you in the attached photo. The oval holes are to afford fore-aft adjustment for belt alignment. The blower can also pivot slightly around the axis created by the bolt going through the mounting lug.

This mount should take me under an hour to make with a hack saw (though I'll default to a saws-all to save my wrists) and file, drill, vise, and hammer. It'll get OEM olive green paint.

Total cost of the front and rear mounts? A little more than a single can of Moss engine paint, no. 220-580 for my '67 1275.

Joel



Edited 1 time(s). Last edit at 2017-12-28 09:04 AM by Yankeedriver.


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Question for Hap:

To the extent possible, I would like to give folks realistic expectations about power increase from bolting this M45 onto a stock engine. Now, we know the result will be roughly similar to the Moss kit because both are M45 Eaton blowers running the same pulley ratio of 1.45:1 (a 'low boost' 3.1" blower pulley and Moss's 4.5" serpentine crank pulley), both start with a standard ignition curve, and both use an HIF44 SU carb with a BCA needle, 4.5 oz spring, and air tool oil in the damper.

To facilitate the experiment, I want to leave my head in stock form (I did a valve job not terribly long ago, but used new stock valves), so will bolt on the high-lift rockers and add the 1.75" exhaust onto my LCB after the initial dyno test. The intercooler will be left out for purposes of the initial experiment.

Aside from possibly lowering the compression slightly and balancing things nicely, the only anticipated change in the bottom end will be a forced induction-specific camshaft. However, I don't want to R&R the cam twice. So, my question is this: in light of your experience over the years, how much would one generally account for the addition of the camshaft? This seems to me to be a little different from comparing naturally aspirated engines with and without a performance cam, but perhaps it's a similar amount...?

Unfortunately, my bottom end isn't fresh enough to simply connect the blower on the dyno and do a before and after comparison. It really needs a rebuild.

I'd appreciate your thoughts.

Joel


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Denis Avatar
Denis Denis Hill
Bearii, Nth Victoria, Australia   AUS
Joel the stock cam works well with the supercharger particularly if the rest of the engine is standard also, It will however still run out of puff at the same revs as the naturally aspirated engine A good supercharger cam will lift the rev range and power higher without effecting low down torque. This is usually in conjunction with an improved head etc. By itself wont hurt but you wont get much benefit either. I am not a fan of hi-ratio rockers with the supercharger. A SC cam has a wide lobe center angle to avoid loosing mixture on overlap and although hi-ratio rockers do not alter valve timing they do increase the overlap at .050". Probably would not affect peak power but maybe mid range. I use std rockers on my B engine with around 100% increase in output. A Burgess SC head and SC cam with all top forged and balanced stuff but stock rockers. The larger exhaust pipe will make a difference. Only just noticed this was a question for Hap, sorry to jump in. Denis



68 B roadster, Daffodil yellow, supercharger, Burgess SC head, SC cam, Mikuni HSR 48 carburetor and engine built for supercharging.

73 BGT V8 conversion starting with a bare shell. Built the engine early in 2016 with high comp pistons and a few other nice bits. Started on the body late 2016 and found Its a lot of work and expense starting from scratch. Did the work myself, mechanical, body. paint etc all except the interior trim.
Finished and going well, great to drive and quick. Now has a nice 3.07 LSD.

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