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Author Topic: Inline-four crankshaft  (Read 215129 times)

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Offline jacksoni

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Re: Inline-four crankshaft
« Reply #285 on: July 05, 2016, 06:00:30 AM »
Looking good Jack. Here are a couple of threads from Speedtalk dealing with this issue. I know Bill Jones from Bonneville- He lives in SLC. Always has good stuff to say.

http://speedtalk.com/forum/viewtopic.php?f=1&t=32174&p=383511&hilit=valve+to+valve+clearance#p383511

http://www.speedtalk.com/forum/viewtopic.php?p=25838
Jack Iliff
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Offline fordboy628

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Re: Inline-four crankshaft
« Reply #286 on: July 05, 2016, 07:37:01 AM »
Worst case valve-to-valve clearance measured all of .030"! :-o But changing from 108.5 degree lobe centerlines to 112.5 degrees (easy to do with dual cams) improves the situation to about .054". Surprisingly, engine simulator software shows very little change to the torque curve from the centerline change- if the software is to be believed. :? Anyhow, I'll be cautious and set them @ 112.5 initially, at least.

Jack,

You might consider running the intake @ 108.5 and the exhaust @ 116.5 to preserve your valve to valve clearance.    If your simulation is PipeMax, there will be little change, if any.   I like to see valve to valve clearance @ overlap somewhere in the .040" plus range, depending on how much I suspect the valve will "waggle around".    Spintron testing has made me "cautious".

My experience with 2v and 4v DOHC engines is that advanced intake events (~2/4 degrees) improve Tq, at little to NO top end penalty, as long as exhaust events are also advanced a similar amount.   This is of course, all subjective, and engine types DO vary, so it might not work.   But at least it is an option to try and as a side benefit, exhaust valve to piston clearance is increased.    Intake valve to piston clearance is, of course, decreased by advancing events.

 :cheers:
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Offline Jack Gifford

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Re: Inline-four crankshaft
« Reply #287 on: July 12, 2016, 12:33:42 AM »
Engine assembly going well. Spun the whole longblock to about 700 RPM for a few seconds (didn't rig up any oiling- just lots of assembly lube on all surfaces)- just long enough to let the valvetrain "settle in" before a final check of valve clearance settings. Still waiting for the welding shop to "stitch up" the blower manifold. Then comes a trial fit in the lakester- to look at clearance around where the magneto and pumps will be, before building the mounts for them to drive off the rear of the camshafts.
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Offline Jack Gifford

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Re: Inline-four crankshaft
« Reply #288 on: July 26, 2016, 11:43:02 PM »
The 14-71 from The Blower Shop (billet case, billet rotors) is a LOT of blower! Shipping weight sans snout, etc. was 100 lb.
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Offline Stainless1

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Re: Inline-four crankshaft
« Reply #289 on: July 27, 2016, 08:41:53 AM »
WOW  :-o is it me or does that thing look bigger than the motor. 
Looking good Jack  :cheers:
Stainless
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Offline RichFox

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Re: Inline-four crankshaft
« Reply #290 on: July 27, 2016, 08:56:30 AM »
How about an 18-71?

Offline Jack Gifford

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Re: Inline-four crankshaft
« Reply #291 on: July 28, 2016, 12:32:54 AM »
18-71 displacement? Rotor diameters?
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Offline Jack Gifford

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Re: Inline-four crankshaft
« Reply #292 on: July 28, 2016, 12:36:47 AM »
... does that thing look bigger than the motor...
Yeah, it does look bigger. And it is bigger- about 511 c.i. compared to the engine's 182 c.i.
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Offline RichFox

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Re: Inline-four crankshaft
« Reply #293 on: July 28, 2016, 07:23:43 AM »
18-71 displacement? Rotor diameters?
The rotors are 21in. long billet hard anodized 120 degree hi helix rotors that are 5.840" in dia. that are teflon stripped on the sides and on the tips to seal the rotors to the case and against one another. Picture with new super high tech hat.
« Last Edit: July 28, 2016, 01:42:24 PM by RichFox »

Offline Jack Gifford

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Re: Inline-four crankshaft
« Reply #294 on: July 29, 2016, 11:46:04 PM »
Ready for a ride to the Ames Performance Pontiac Nationals (Norwalk, Ohio) next week.
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Offline Jack Gifford

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Re: Inline-four crankshaft
« Reply #295 on: August 09, 2016, 11:55:51 PM »
Had an enjoyable weekend- lots of interest in my DOHC conversion.
Watched Eric Larsen's 'Boss Bird' (nostalgia fuel funny car tribute to Arnie Beswick) run the quickest/fastest quarter-mile ever with traditional Pontiac V8 power- 6.02 seconds at 232 MPH!
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Offline tauruck

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Re: Inline-four crankshaft
« Reply #296 on: August 19, 2016, 07:35:28 AM »
Jack. Was I hearing things on the live stream???. You broke a record.  :cheers: :cheers: :cheers: :cheers:

Offline Jack Gifford

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Re: Inline-four crankshaft
« Reply #297 on: August 20, 2016, 12:26:25 AM »
Say what? :?

Finished the crank scrapers. Still need to fabricate a windage screen, then the engine can be buttoned up.
Custom oil pump from Dailey Engineering is on the way- separate pressure and scavenge sections for top- and bottom-end, centrifugal air separator, and provisions to mount Hilborn fuel pump on the rear. Mounting for it behind the intake cam is done, just need to machine a short drive stub to go between the cam and pump.
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Offline fordboy628

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Re: Inline-four crankshaft
« Reply #298 on: August 20, 2016, 05:48:05 AM »
Wow Jack, Dailey engineering dry sump system,  FIRST CABIN!

BTW, everything looks fantastic!    I envy your machining skills.

 :cheers:
Fordboy
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I used to be a people person.  But people changed that relationship.

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Offline Jack Gifford

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Re: Inline-four crankshaft
« Reply #299 on: August 20, 2016, 11:21:51 PM »
Pontiac guys will notice in the above photo that the passenger side outboard row of main studs isn't where Pontiac put it. I moved them further outboard so they anchor (3/4" long HeliCoils) into the more massive area where the strengthening rib intersects each main web. Every little bit helps? :|
« Last Edit: August 20, 2016, 11:24:40 PM by Jack Gifford »
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