MGExp

MG Midget Forum

DIY supercharger option - with EFI!!!

Moss Motors
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor
AutoShrine Sponsor

Denis Avatar
Denis Denis Hill
Bearii, Nth Victoria, Australia   AUS
This is a pic of my old home made tensioner that I ran for several years and how close it was to the crank pulley. The new one is the same. 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 "3.9L Rover" early in 2016 with high comp pistons and a few other nice bits, plus a T5 ford trans. Started on the body late 2016 and complete late 2017, Did all the work myself, mechanical, body. paint etc.
Finished and going well, great to drive and quick. Now has a nice 3.07 LSD.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <

Attachments:
IMG_1652.JPG    42.1 KB
IMG_1652.JPG

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3668755 by Denis This is a pic of my old home made tensioner that I ran for several years and how close it was to the crank pulley. The new one is the same. Denis

Denis,

Thank you for taking the time to send the pics. As I say, the angle of the run to the blower is quite different from going directly up to the alternator--which of necessity is mounted much lower in this right-hand blower setup. But these mounting details are helpful, and I'll certainly take another look at this possibility and report the results, along with those from Adrian's suggestions.

Thanks again!

Joel


Member Services:
Innovative DIY performance and reliability upgrades.
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3668261 by pinkyponk Better belt wrap... but I'm not sure about tensioning the belt outwards. Or the V grooves not engaging the alternator pulley.

Adrian

Sorry, missed this concern the first time around. Micro-v engagement with the alternator is not a problem because I'm now using a double-sided, 5-rib VW/Cadillac/et al, belt. It is really grippy!

So, assuming I can find with a CCW tensioner with a grooved pulley--which I am 99% sure that I saw in my last reconnoiter--and whose fore-aft dimensions will fit in that cramped space, this configuration could well be a winner. As I've said, lots of vehicles push the belt outward, and this diagram gives so much crank wrap that doing so wouldn't be a concern.

Ah... here is an outward, grooved tensioner on a Chevy Silverado, for instance... well, but it's CW, not CCW. Anyway, I'll try these and Denis' suggestions this weekend.

Joel



Edited 1 time(s). Last edit at 2018-01-26 09:17 AM by Yankeedriver.


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
2007-chevrolet-silverado-3500-6-6l-serpentine-belt-diagram.jpg    10 KB
2007-chevrolet-silverado-3500-6-6l-serpentine-belt-diagram.jpg

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
So, I was disappointed to learn that Adrian's sketches in posts 457 and 461 won't work because the belt is nowhere near long enough. 457 is the most viable because room--both laterally and fore-aft--is really limited. The bulk of the body of tensioner designs (other than the Avalanche, which won't work) is prohibitive in this cramped area (I've tried a half-dozen tensioners over the past few months--thank goodness for Auto Zone's liberal return policies).

462 won't work because the upper run it creates contacts the underside of the head where it protrudes for the thermostat--something I'd run into in earlier experiments and had forgotten. Also, the belt isn't nearly long enough. I have only been able to find a half-dozen double-sided, 5-rib belts (and no 4-ribbed versions in anything like these lengths).

However, this exercise suggests what may be the only other alternative to my top-mounted sliding tensioner, attached. The idler returns to the earlier mounting position, which is simply 3/8" stainless all-thread passed through the OEM belt-tensioner bolt hole with beefy spacers. Very sturdy/rigid. This time, of course, we would use a ribbed/flanged pulley instead of a smooth one for the two-sided belt, but it should fit because the O.D. of the two Dorman pulleys is the same, if memory serves.

The only thing that's misleading about the sketch is the same thing that complicates all of the other iterations--the extremely limited space, given the lowered alternator necessary to fit the blower and alternator adjacent to each other. Again, it's the body containing the spring that typically is too bulky. However, I'm going to try a few more alternatives that conceivably work--a Corvette tensioner pictured and the standard types I've posted before, albeit now working in the CCW direction--before just going with a good old slider.

Oh - a final possibility along the lines of Denis' initial, homemade tensioner, is the attached Chevy Impala/Monte Carlo unit. That would generate pressure in the correct, outward/downward direction. It's body may be too large to fit, but if so, if I were to unbolt the lever and spring portions, they might be affixed to existing bolts or a tab attached to the bolts, that might possibly fit. I think I've seen other versions of this kind of tensioner that could conceivably work as well.

We'll see!

Joel


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
alternative belt routing.jpg    39.9 KB
alternative belt routing.jpg

Corvette tensioner.jpg    11.3 KB
Sign In or Register to view this photo
Chevy Impala, Monte Carlo tensioner.jpg    7.5 KB
Sign In or Register to view this photo
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
*Update: the head machinist/owner of the neighborhood CNC shop called yesterday to discuss a way of possibly eliminating an entire setup from production of the 5-rib crank pulley. If it works, the cost would be reduced significantly, as the part could be made entirely on the big CNC lathe, rather than having to do a second setup on the mill. I've got some related research to do, but it looks encouraging. Also, yesterday I sent off specs for a second bid on the 5-rib H20 pulley.

If I'm successful in driving the price down, this pair of pulleys would benefit anyone doing a DIY supercharger project of any kind--such as Adrian's Aisin-based project--or folks who just want to convert to serpentine and discard the old V-belt.

Joel



Edited 2 time(s). Last edit at 2018-01-27 11:11 AM by Yankeedriver.


Member Services:
Innovative DIY performance and reliability upgrades.
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Well, as you can see from the first photo, the alternative in #469 won't work, either. It puts the outer/lower corner of the belt too close to the shock mount--marginally okay here, but would definitely interfere with OEM lever shocks. Also looks like it might foul the steering gear on a right-hand drive car as well.

Another option, photo no. 2, is to run the belt entirely differently (the idler would move to the left on the angle iron to avoid fouling the underside of the head--no problem), and put the avalanche or other tensioner to push out on the belt. That would reduce the crank wrap to about 1/2, which is what a lot of modern production vehicles have. The water pump pulley will get slightly more wrap than shown here due to moving the idler over to avoid fouling the head--but the water pump requires precious little torque to spin, and this 5-rib belt is very grippy.

A third option, last photo, is to use the new routing in photo no. 2 or return to my last routing configuration, but instead of using the top-mounted idler as a sliding tensioner, mount the Avalanche tensioner just beneath the nose of the blower, pushing inward on the run coming from the crank. It doesn't look like it from this angle, because the belt isn't very tight, but there is sufficient room for deflection. This is especially so if I move the blower outboard a little more. Plenty of room to do that, as there's nearly 2" to the brake union and wiring loom on the inner fender, and easily accomplished by simply making another rear mount. Those are super easy to make with a drill, vise, hacksaw and file.

One nice thing about this option is that the mount for the Avalanche tensioner would be either a simple L-shaped piece of the 3" steel bar used to make the rear mount, or some of the leftover angle iron used for the front. You just bolt that to the underside of the same two front mounting lugs that will receive the remaining piece of the front mount that attaches to the angle iron.

All that said, option two also creates a nice dip in the belt for passage of the snorkel. I'm going to revisit the diagrams of modern production cars to see how much of the crank pulley needs to be contacted. I'm pretty sure I've seen numerous vehicles with 1/3, which this would net, but need to check my memory.

Joel


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
alternative belt routing .jpg    51.7 KB
alternative belt routing .jpg

alternative belt routing (2).jpg    53.3 KB
Sign In or Register to view this photo
alternative belt routing (3).jpg    44.2 KB
Sign In or Register to view this photo
pinkyponk Avatar
pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
I'm tellin' ya... 2 belt system. Easy peezy. grinning smiley

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.

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3669711 by pinkyponk I'm tellin' ya... 2 belt system. Easy peezy. grinning smiley

Adrian

Adrian,

None of your sketches suggest that solution... did I miss something?

Joel


Member Services:
Innovative DIY performance and reliability upgrades.
pinkyponk Avatar
pinkyponk Gold Member Adrian Page
Berwick, NS, Canada   CAN
No. Sorry... just being silly. I was referring to the way I did my supercharger. I thought 2 belts was dismissed earlier. I use a regular, stock MGB fan belt and a separate 4 rib serpentine on my setup. I think it's a better setup than a single belt. I can drive home if something goes wrong with my blower. I'd still have a water pump and alternator.

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.

. Hide banner ads & support this website by becoming a > Gold Supporting Member <
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
In reply to # 3669822 by pinkyponk No. Sorry... just being silly. I was referring to the way I did my supercharger. I thought 2 belts was dismissed earlier. I use a regular, stock MGB fan belt and a separate 4 rib serpentine on my setup. I think it's a better setup than a single belt. I can drive home if something goes wrong with my blower. I'd still have a water pump and alternator.

Adrian

I actually would be perfectly happy with a two-belt system--and the aftermarket pulley I've got bolted on temporarily has a front 4-rib section. The concern was mainly that a combo V-belt and serpentine might not work--plus just general preferences for a single-belt system.

Logistically, the blower's snout would have to go forward another inch to line up--not hard to do mount wise at all, but doing so may well cause the blower pulley to foul the bonnet at the blower's current height.

That said, I've mounted the CS121D and as Mark suggested, it's substantially smaller in diameter than the CS130-style, earlier Saturn model. So, if a new alternative routing I came up with upon waking this morning doesn't pan out next weekend, I may well lower the blower, shift it forward a inch, and do a two-belt system. That would of course use the existing alternator-actuated tightening system (stock adjustment piece, alternative bolt hole) to tighten the 5-rib belt, and the avalanche tensioner tightening the 4-rib belt from the existing water pump pulley to the blower.

Joel


Member Services:
Innovative DIY performance and reliability upgrades.
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
I think I've arrived at a single-belt setup that has all the preferred attributes:

(i) single serpentine belt system, compatible with either double-sided or less-expensive single-sided 5-rib belt;

(ii) CW rotation on the alternator, so compatible with OEM late model Lucas, CS130-style or CS121D-style Saturn 90-amp version; and

(iii) belt tensioner immediately after the crank pulley on the 'slack' side.

I will try this weekend and we'll see if this does it. But a neat attribute of this routing is that one can use the OEM adjustment strap or turnbuckle instead of a spring tensioner if there isn't room for the Avalanche or other tensioner in the indicated location or farther up the run to the supercharger.

P.S. Adam agrees that with a 5-rib belt, which is what the Saturn alternators use in the OEM setup, half the pulley is sufficient wrap; he pointed out that 1/3 is not unusual.

**Update: this was easy to configure. Had to spend much of the day on the wife's Volvo, so out of good light for a photo. But I did a string test and it's going to work, and should enable all three of the above--for sure the first two. Dayco has single-sided 5-ribs that will accommodate the setup, no problem.

I'll see if I can figure out an easily replicated way of mounting the Avalanche tensioner, down by the crank in the long run before the blower. If not, I found an $18 Dayco sliding tensioner that has a screw adjustment and which looks like it'd mount in the same place (photo attached).

So, should be shifting back to the DIY EFI project this month... can't wait to have a driveable car again!

Joel



Edited 2 time(s). Last edit at 2018-02-04 09:24 PM by Yankeedriver.


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
Serpentine belt routing CW.jpg    37.7 KB
Serpentine belt routing CW.jpg

Dayco89031 copy.jpg    18.8 KB
Sign In or Register to view this photo
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
*Update: the 5-rib crank pulley is indeed going to be a one-machine operation (the big CNC lathe), so will be substantially cheaper than expected--and much less than the existing offerings from the UK companies and Moss. I have sent off the specs to Nate for a second bid on the 5-rib H2O pulley, so should have that this week.

So, folks should have a 5-rib serpentine belt kit available soon for forced-induction, EFI, or just upgraded belt drive for naturally aspirated cars. For those like Rick, who have already upgraded to a turnbuckle over the OEM strap-and-clamp setup (he did it without having to trim the motor mount tab, as I had done), this means all A-series drivers can go serpentine, get superior grip, and not worry about V-belt slippage or breakage for ~30K miles or more at a stretch.

Joel



Edited 1 time(s). Last edit at 2018-01-30 09:57 AM by Yankeedriver.


Member Services:
Innovative DIY performance and reliability upgrades.
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
Got a call on the H2O pump pulley, 5-rib version, and it's going to be less than $100. That's a really good deal, as Moss' 4-rib Version is over $150. Assuming it lines up nicely, which I'm sure it will with a machinist this experienced, he's going to make them available to all A-series owners. I'll link to his website when that happens.

The 5-rib crank pulley, which I'm having made locally, is delayed because sadly the owner is in intensive care. I haven't had the heart to press his son, who's running the shop in his absence, for when this job will be done.

However, great news is we're just a few weeks away from a 5-rib serpentine conversion kit for 'roll yer own' supercharger folks, and anyone else who just wants to convert their A-series to serpentine.

Joel


Member Services:
Innovative DIY performance and reliability upgrades.
Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, NM, USA   USA
So, here is Nate's 5-rib A-series H2O pump pulley. Very nice, and at $90, $65 less than the Moss 4-rib version. It isn't anodized, which I don't mind as it isn't down low subject to salt spray in the winter, like the crank pulley potentially is (I will be probably be anodizing my 5-rib crank pulleys, for that reason). Mine will get the olive green OEM engine paint on the 'dome' but not where the belts ride, probably.

Nate will let me know when he's got them on his website for Adrian or anyone else doing an A-series DIY blower project, or just wanting to go serpentine. The latter will be a new DIY project on my website soon, by the way.

Looks like another 6-day working week, so likely won't get much done tomorrow on the project. But I'm hoping Sunday to figure out whether I can indeed put the Avalanche tensioner on the long run. If not, it'll probably be an outward-pushing spring or sliding tensioner... and that's it!

I'll post whenever the foreman of my neighborhood shop gets out of intensive care and I've got the 5-rib crank pulleys available.

Joel


Member Services:
Innovative DIY performance and reliability upgrades.

Attachments:
Smooth Flow 5-rib A-series H2O pulley.jpg    58 KB
Smooth Flow 5-rib A-series H2O pulley.jpg

mster50 Silver Member Mike Sterling/A
Zanesville, OH, USA   USA
1980 MG MGB
You'd think belts would not be that difficult. There is a lot there, good job.

. Hide banner ads & support this website 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





Join The Club

Sign in to ask questions, share photos, and access all website features

Your Cars

1969 MG MGC

Text Size

Larger Smaller
Reset Save

Sponsor Links