The Jalopy Journal
Discussion in 'Traditional Hot Rods' started by Jiminy, Oct 1, 2020.
Your good instincts for a strong build, starting with a STRONG foundation ...is right on !
You can confidently add HP to a strong base !
The worry, doubt and broken equipment comes when straining weak parts.
Relative to scat crank talk... loo at ‘puny’ rod size. At one time, I had a collection of pictures I took of broken scat cranks, that occured when too much was asked of the crank...especially drilled for oiling.
There used to be a fellow banger guy who visited here name: Sandman.
If you ever talk with him, ask him about scat !
I defer to you guys ..but the scat using dipper rods will hold up to that head design for street use,even hill climbing..I wouldn't cross drill an A rod journal due to inducing weakness. Phil didn't mention his ultimate goals other than OHV,if he's thinking salt the sky's the limit..adapting that head design to the street,basically limiting its potential some negates some of the lower end requirements is my point.
unfortunately i resemble that remark ........
The Scat crank was never considered as an option. To me it doesn't make sense to spend that much on a crank that still uses the Model A journal size.
One thing I didn't mention, was a harmonic damper. possibly a Murray Horne unit. I talked to ATI Superdamper last year at SEMA. They have a 5.5" serpentine damper that I think will clear the front U-bolts. Since the hub bolts into the damper, it would just be a matter of building a hub to fit the A/B crank. They told me they had made flathead dampers. I would want to use a larger water pump pulley, to compensate for the larger diameter damper, which are available from the stock car guys.
Here is my concept overlayed with a Clings pulley.
Harmonic Balancer Assy by nomadpsd, on Flickr
I know there is a lot of information about harmonic dampers on the web. Some swear by them, others not. There is a real potential here on these motors.
I will caution you that there might be a snag in the application. Granted, the failures I have had are possibly not applicable to all, but, the drive key should be a source of attention.
There is a reason the Small Chev V8 has more key and a press fit onto the crank. And yes, we shook the Mazda race ones off also above 9k revs (not press fit, solution was to make press fit).
Yes, the press fit was something I discussed with ATI and they said was needed. I also thought of adding a second key.
Again, this is probably not really needed for my application. But, I like thinking outside the box.
I would like to run some kind of damper. Because I think they are beneficial. And, I want to run a serpentine belt for better belt engagement on tiny alternator pulley. Which leaves me limited on options.
There are flywheel dampers also.
I've got seven, 22# and seven, 33#
Sterling dampening flywheels shipping from the UK next week. Have four 64# ones on hand.
Sent from my XT1585 using The H.A.M.B. mobile app
That's a big investment!
Just letting folks know.
I've got 4 of them pre sold.
They do work!
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Murray Horns damper is a tight fit and full key... I run one on a stock A crank with a lube line to the center main with a set up like you have already Phil.If your going dynamically balanced get a beaver tail (early A) crank,go as light with the rotating group as you can,it might not last forever but it will be fun,with that head a light rotating group will spool up quick..just my opinion,but the lighter journals benefit more from counterbalancing (Scat),but all that is moot if you don't tour with the engine.For a quick bar hopper/occasional hill climb a light stock crank and flywheel with a harmonic balancer and a few pounds pressure to the center main would be a hoot,especially with that head..
I'm having zero luck locating the article you mentioned since FAST has shut down. Do you have a link or a copy?
I've been wondering this also. I keep finding references to old articles I'd like to read. It would be a great help to have an archive somewhere.
That article was not in the FAST realm, it is from SOSS
I think I have a copy in the pile, I'll look this weekend.
I run a ATI SBC damper on my Bonneville B engine, I made a hub adapter with a full length 3/16" ket way with a press fit on the crank snout, it is a moldex crank, not that would make any difference. A crank snout damper will not be effective unless it is a press fit.
I also have one of winduptoy's "rattler flywheel dampers" it smothed out the Model B street engine and allowed it to rev at least 500 more rpms, I am very happy with it.
OK, located the article from Wayne Atkinson
It is in Volume 4 Number 3 Jan 1995 Secrets of Speed Society SOSS.
Check with Charlie on the website.
NICE looking ride !
Would you share a picture and some details of your B construction stats ?
Thanks for sharing the info re the SBC dampener you use for racing B. Is your engine w/girdle ?
Contacted Charlie, renewed my subscription, got the article. Thanks for your help!!
1. Picture of Moldex Crank, girdle, cam supports, ATI Damper hub, and adaptor installed on crank.
2. drawing of crank to hub adaptor with 3/16" keyway the full length of the adaptor welded to ATI Hub then ground to spec for press fit then keyway was cut.
3. Assembly installed on engine.
THANKS for sharing.
You do nice work.
You running a FLATHEAD ?
Picture is ‘ fuzzy’ , on my screen. Cant see intake valves....maybe because aint none. Got to change oil ... on this screen. lol
Hi ho there I have not posted on here before more of a read and learn guy. I pick up a really nice AC 4,000 RPM tach at the swap meet today does some one make cable drive distributer that are available or did I buy a neat tach that is never going to operate in my car any help please.
If you are planning on using it on a Model "A", you better plan on building a REAL strong motor before you plan on "pegging" that tach!! ...Just sayin'...
You have a few choices. You could modify one of the V8 flathead Mallorys or there is a Mallory for MGB's 2432002 that modified will work also. Or if you are in need of something more period correct between the 30's and 40's there is a Stewart Warner tach drive that mounts under the dist.
Excuse my ignorance but what is the story with the ring gear on the flywheel dampener?
How do they fit up to the flywheel and clutch?
Just curious and never seen these before.
It's a flywheel with a damper built into it, replacing the original flywheel and uses a V8 clutch. Look up vibrationfree.co.uk
Cheers, I will do. The pic you posted is obviously the crankshaft side.
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