Author Topic: Belly Tank Build Diary  (Read 361895 times)

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Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #210 on: November 27, 2016, 06:37:25 PM »
I machined holes in a piece of 3/4" thick plastic that would locate the alternator in the space available.  I bolted the alternator to this piece of plastic and clamped the opposite end to the blower pulley.  This kept the alternator aligned with the blower pulley so that I could mock up a mount.  I ended up removing the factory charcoal canister purge valve that came with this crate engine.  I machined a 1" thick piece of steel to block the valve location.  I then realized that I could use this piece of steel for one end of the alternator mount.  I bent up a piece of 1" diameter DOM tube that I had left over from the roll cage.  I added a brace from 1/4"x1" thick steel.  A lower mount was made from 1/4" thick steel plate.  The top view attached shows the upper mount. 

Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #211 on: November 27, 2016, 06:42:38 PM »
The photo leaves some to be desired but you can just see the 1/4" plate steel of the lower mount just to the right of the engine oil filler.  This plate is secured to the end of the head with two bolts in existing tapped holes.  A spacer made from 7/8" steel rod connects the bottom mount of the alternator to this steel plate.  The mount is very secure with no vibration when the engine is running. 

Now to redesign those steering arms that were flexing giving me some shimmy. 

Offline Jack Gifford

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Re: Belly Tank Build Diary
« Reply #212 on: November 28, 2016, 01:29:59 AM »
It appears that you're going to extremes (synchronous drive, 10K armature RPM) to have 65 amps (over 780W) available. What will demand that much electrical power?
M/T Pontiac hemi guru
F/BFL 1-mile Loring record 2020

Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #213 on: November 28, 2016, 07:49:29 AM »
It appears that you're going to extremes (synchronous drive, 10K armature RPM) to have 65 amps (over 780W) available. What will demand that much electrical power?

The LSA requires a vacuum/boost referenced fuel system with up to 68 psi of pressure.  I am running an Aeromotive Eliminator fuel pump.  The pump alone requires almost 15A of current.  The engine cooling system water pump draws about 14A.  The intercooler pump is another 10A of current.  The ECU idles at a couple of amps however the ignition draws over an amp per 1,000 rpm.  At low rpms I need about 40A of current which requires that the alternator be spinning very fast.  The alternator is rated for a maximum of 18,000 rpm.  I use toothed timing belt drives because I like them.  They are very compact and don't require any pretension to keep them from slipping. 

Offline RichFox

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Re: Belly Tank Build Diary
« Reply #214 on: November 28, 2016, 11:51:59 AM »
I am to cheap to buy new pulleys. In this case I used Honda Gold Wing cam drive pulleys from a junk yard to drive an oil pump on a 28 Chevy. Turned the stock pulley to 1 1/4 and bored the Honda pulley to fit. Brazed them together. Made guide plates to keep the belt on and brazed them on the center and through holes to 5 teeth on the outside. Looked at how close I could mount the pump and compared that to belt sizes and ordered a belt from an industrial hardware store. Before and after pictures of the pulley. I need some aluminum to mount the pump so I can finish this.

Offline Jack Gifford

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Re: Belly Tank Build Diary
« Reply #215 on: November 29, 2016, 01:04:29 AM »
Thanks for the info Mike. I hadn't considered all the pumps being electric.
M/T Pontiac hemi guru
F/BFL 1-mile Loring record 2020

Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #216 on: November 29, 2016, 07:30:34 PM »
Safety is important and even little things can make a difference when you are having a "bad day".  I saw the results of a fire in the engine compartment of a land speed car.  Thanks to the on board fire suppression system the worst was some burnt wiring.  The fire happened when blow by pushed the dipstick up out of the tube spraying oil on the hot exhaust.  The oil spray continued feeding the fire until the engine was shut down.  I decided that it would be good to secure the dipstick on my car to help prevent this from happening.  I added a standoff and bracket to the engine so that the dipstick could be secured with a wire tie. 

Offline Stainless1

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Re: Belly Tank Build Diary
« Reply #217 on: November 30, 2016, 12:16:23 AM »
Covering the bases will keep you from saying "well shit" how did that happen... keep applying the lessons learned the hard way by others... it doesn't have to happen to you to learn from experience.
 :cheers:
Stainless
Red Hat 228.039, 2001, 65ci, Bockscar Lakester #1000 with a little N2O

Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #218 on: December 06, 2016, 08:25:12 PM »
A photo of the upper alternator pulley.  I machined the pulley for very close (slight shrink) fit on the press fit hub of the factory upper supercharger drive pulley. 

Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #219 on: December 06, 2016, 08:27:00 PM »
I machined a drill jig that I could clamp around the pulley to get straight holes to insert roll pins.  Red Loctite was also used to secure the pulley to the hub. 

Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #220 on: December 06, 2016, 08:30:41 PM »
A photo of the completed alternator drive.  By virtue of a careful selection of pulleys and belt no idler or slotted brackets were needed.  The alternator puts out 26A of current at idle.  The car draws 33A of current at idle with all the pumps running except the intercooler.  As soon as the engine rpm comes up off idle the alternator current goes above the draw. 

Offline Glen

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Re: Belly Tank Build Diary
« Reply #221 on: December 06, 2016, 08:35:28 PM »
Mike, use a piece of safety wire in place of the tie wrap, a flash of flame will melt it in seconds Just a thought.
Glen
Crew on Turbinator II

South West, Utah

Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #222 on: December 06, 2016, 09:24:12 PM »
Mike, use a piece of safety wire in place of the tie wrap, a flash of flame will melt it in seconds Just a thought.


Glen,

Thanks for the recommendation.  I will change to safety wire or a stainless steel wire tie. 

Offline Frank06

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Re: Belly Tank Build Diary
« Reply #223 on: December 21, 2016, 05:19:19 PM »
Mike, I just read this whole thread and enjoyed it immensely.  I didn't see how fast you went at Wilmington, but am curious if rear brakes only worked the way you thought they would?

thanks,
Frank
E-Racer

Offline Mike Brown

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Re: Belly Tank Build Diary
« Reply #224 on: January 01, 2017, 07:54:42 PM »
Mike, I just read this whole thread and enjoyed it immensely.  I didn't see how fast you went at Wilmington, but am curious if rear brakes only worked the way you thought they would?

thanks,
Frank

Frank,

The dual caliper disk brakes on the rear felt spongy to me before I went to the track.  There are a lot of loops in the brake lines and I have 2 psi residual check valves. I bled the brakes conventionally and with a vacuum bleeder.  They still felt a little spongy.  I went 125mph at Wilmington for my first licensing pass.  I slowed down to 90mph at the traps with concerns about how well the brakes would work.  I smoothly let off the gas as Keith recommended and then eased into the brakes.  The car slowed down quicker than I could have ever imagined.  I actually had to get back on the gas to make the first turn off which I think is 3/8 mile past the traps.  So I am no longer concerned about the brakes and am well pleased with their performance.