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DIY supercharger option - with EFI!!!

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trevorwj Avatar
trevorwj Trevor Jessie
Louisville, KY, USA   USA
Denis makes a good point. While many of us want to know how much HP is gained, the true benefit of a supercharger is how the power curve changes and gains in torque when rolling into the throttle. There are many benefits to a supercharger that are not represented on the dyno graph of a full throttle power pull.

I know it doesn't answer your question, but I would get too hung up on that peak HP number.



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Sprite1956 Roger Parry-Jones
Melbourne, Victoria, Australia   AUS
Fascinating discussion, which I dip into occasionally. I probably will never try this technical development but I dream and speculate. Keep pushing the boundaries guys (and women). Love it!

Roger

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
In reply to # 3653438 by Denis 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

Denis,

I am certain Hap won't mind. The whole point of this thread is to draw on the breadth of experience, quite literally from all corners of the Spridget-driving world available on this site.

As for the high-lift rockers, reasonable minds can differ, as the saying goes, and the neat thing about them is that, unlike a cam, they can be R&R'd in a morning without removing the engine. At any rate, if I don't like them, they can go on the Bugeye I'll be shopping for when I get around to framing the separate residence for my aging father, which will have a Spridgets-only shop as the first level (good thing I got the shoulder repaired!). Also, one can look forward to Gene Wilders' line from Young Frankenstein: "Nice rockers!" I see that Adrian uses them with his supercharged rig, so will be interested to hear his thoughts.

Anyway - thank you for the thoughtful response.

Joel


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
In reply to # 3653501 by trevorwj Denis makes a good point. While many of us want to know how much HP is gained, the true benefit of a supercharger is how the power curve changes and gains in torque when rolling into the throttle. There are many benefits to a supercharger that are not represented on the dyno graph of a full throttle power pull.

I know it doesn't answer your question, but I would get too hung up on that peak HP number.

Trevor,

That makes sense. I personally am less interested in numbers, but as you say many people want some concrete figure to balance against the time and expense of doing [x] modification. I'm just wanting to be transparent and informative for people who want that info. That said, what you point out suggests that some good cockpit videos--and probably a 'drive-away' video, and roll-on clip taken from another car on the highway, will speak volumes.

Joel


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trevorwj Avatar
trevorwj Trevor Jessie
Louisville, KY, USA   USA
I'd suggest logging the drive with an app that records acceleration and speed to include with the videos for those people that like numbers.



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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
In reply to # 3653580 by trevorwj I'd suggest logging the drive with an app that records acceleration and speed to include with the videos for those people that like numbers.

Trevor,

Do you know of such an app you could recommend? Do they work with a phone or laptop...?

Joel


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Denis Avatar
Denis Denis Hill
Bearii, Nth Victoria, Australia   AUS
Get everything as good as you can before you go near a dyno. Mixture over the range , ignition close and driving well. Unless you want to throw heaps of $ to the operator you just don't get time to do it all on the day. Peak timing is set on the dyno and it may pick a fault in your advance curve but not the best to set it up unless you have a programmable ignition and it would want to be close to start with. You cant always rely on the operator knowing as much about your car as you do. 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. Future mods, maybe an increase in gearing but not for a while.

trevorwj Avatar
trevorwj Trevor Jessie
Louisville, KY, USA   USA
Someone once suggested this app: http://racerender.com/TrackAddict/Features.html

In reply to # 3653630 by Yankeedriver
In reply to # 3653580 by trevorwj I'd suggest logging the drive with an app that records acceleration and speed to include with the videos for those people that like numbers.

Trevor,

Do you know of such an app you could recommend? Do they work with a phone or laptop...?

Joel



Midget 50th - A Spridget Event
It was a Blast!
http://sprite-midgetclub.org/

Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
Denis - definitely don't have heaps of cash to throw, so sound advice.

Trevor - that's pretty neat, thanks. I may try the free trial.

P.S. - Got home from work and bent up the rear mount in the sketch I posted recently. It supports the blower fine but is too finicky to make--like folding oragami. I'll make a simpler version after work tomorrow that is just an L with a drilled aluminum block replacing the hard-to-make parallel tabs. Much easier to replicate accurately, more forgiving design for first-time fabricators, and uses up what would've been surplus aluminum from the front mount.

Joel


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
Had a couple of hours after work before supper, so made up the much simpler rear mount. Slotted holes in the short part of the 'L' that bolts atop the alternator mount allow ample fore-aft movement to align pulley.

Man, is that 3/16" steel rigid with the force straight down on its edge. Second photo is the blower supported solely by the rear mount attached to a single lug on the blower. Together with the front mount tying the head to both forward lugs, she ain't goin' anywhere.

The axis of the bolt through the lug allows rotation in an arc to align the blower's axis in the plane parallel to that of the crankshaft. The tabs from the front mount have slotted holes in the same plane.

The 3/16" bar cuts like butter with a saws-all, but one could do it with a hack saw. The relaxed radius bend is easy with the bar in a vise, and force exerted by a big monkey wrench and 2.5 lb. hand sledge or large ball peen.

Last photo is how the setup looks after a few glasses of champagne! Happy New Year!

Joel



Edited 2 time(s). Last edit at 2017-12-31 08:37 PM by Yankeedriver.


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
Two updates:

First, several people have been nice enough to make suggestions that have produced two front-mount alternatives: for vertical-flow models, a simple angle-iron piece pictured here, but which will be mounted on a longer cylinder head stud with a little drilled block and Moss's heavy duty flanged nut (total time to fabricate, around 1.5~2 hrs); or an even simpler straight steel bar (total time, perhaps 20~30 minutes) extending from the late model Spridget's thermostat housing shown in the second photo. Both will attach to a steel plate that bolts to the blower's front two lugs. Both allow an attachment point for the upper mounting bolt of the Avalanche belt tensioner.

Second, I'm headed over to the CNC shop today or tomorrow, and if I like what I hear on the bid, will green light the short run of HIF44 snorkel/inlet adapter flanges.

These will be useable by anyone who wants to run forced induction on any vehicle using an HIF44 carburetor, or for that matter those with a naturally aspirated car who simply want to run a snorkel from their HIF44 to a remote air filter to pipe in cold air (from under the fender, as in my chosen route). So, these will be sold separately for those folks.

Joel



Edited 1 time(s). Last edit at 2018-01-02 02:43 PM by Yankeedriver.


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
So: green-lighted the HIF44 adapters. As I've said, these are useful to:

(i) anyone who wants to run forced induction (turbo or supercharger) on any vehicle using an HIF44 carburetor;

(ii) anyone with a naturally aspirated car who wants to run a snorkel from their HIF44 to a remote air filter for a 'cold air intake' with air ducted up under the fender, as in the attached photo, or with a duct leading down to an air filter behind the grill; and

(iii) anyone with a naturally aspirated car who wants to direct-mount a K&N-style air filter to their HIF44.

They'll be on the website as soon as the production run is finished. I ordered more than just the initial 11 (one for me; ten for the DIY supercharger kits), since they've got a broader application than this conversion.

Joel



Edited 1 time(s). Last edit at 2018-01-03 08:43 AM by Yankeedriver.


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Speedracer Avatar
Speedracer Platinum Member Hap Waldrop
Greenville, SC, USA   USA
1967 MG MGB Racecar "The Biscuit"
Yeah I don't see an issue , the angle iron, which is some hard stuff, just replaces the hardened washer. Anytime I mill cut some flat bar, or angle I am always surprised at how hard it is.



Hap Waldrop
Acme Speed Shop
864-370-3000
Website: www.acmespeedshop.com
hapwaldrop@acmespeedshop.com


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Yankeedriver Avatar
Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
In reply to # 3655573 by Speedracer Yeah I don't see an issue , the angle iron, which is some hard stuff, just replaces the hardened washer. Anytime I mill cut some flat bar, or angle I am always surprised at how hard it is.

Hap,

Glad you agree. That angle is really stiff, especially in that short length. The front mount should be done next weekend, and it and the rear (already done) will get a coat of OEM green engine paint. Should look pretty nifty against that silver-and-black blower.

By the way, unless I get a nasty surprise from the tax man (unlikely), I'll be giving you a call later this month or in February to discuss my rebuild. Don't want to throw a rod when I connect the serpentine belt to that blower, as the rings and crank bearings are a bit tired!

Joel



Edited 2 time(s). Last edit at 2018-01-03 08:51 AM by Yankeedriver.


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Yankeedriver Platinum AdvertiserAdvertiser Joel Young
Albuquerque, New Mexico, USA   USA
Settled on an idler pulley, the Dorman 419-610 pictured here. It's a steel pulley with a black anodized finish and decent quality, very smooth bearing. Pretty good for $13.00 (Amazon).

Best of all, the pulley simply slips onto on a longer 3/8" bolt that will replace the OEM alternator adjustment bolt (it has a removable bushing whose I.D. is 3/8"winking smiley. Together with the Avalanche tensioner between the alternator and blower, the routing should result in sufficient contact with the alternator pulley.

All in all, it's going to be a tidy and really simple belt setup. I need to get with Nate at Smooth Flow to see whether he's still interested in providing A-series-specific H2O pulleys for folks to order on-demand, but last I spoke with him, sounded like he would.

Joel


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