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Alexander_Monday Samba Member

Joined: November 09, 2007 Posts: 382 Location: Springfield Missouri
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Posted: Sun Jul 06, 2025 9:28 am Post subject: Crank center line |
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2387 flanged crank engine which will have 12 to 15# boost.
Lathed #1 barrel to 0 deck and cut the rest to the same length.
Appears CB (or Autolinea) milled the decks off the parting line not the crank centerline.
Opinions on running it this way?
Compression isn't affected enough to worry about, but the bores are not parallel with the stroke.
I just don't know if it is off enough to make a realistic difference.
I would have to ship the case 1/2 way across the USA to get it corrected.
My equipment isn't big enough to do it right. _________________ Danth’s or Parker’s Law:
“If you have to insist that you've won an internet argument, you've probably lost badly.”
Alexander_Monday->What were the rings gapped at?
bedlamite->Almost enough.
andk5591 wrote: |
The original german engineers have attained sainthood and it is impossible to improve perfection.
Anything that anyone does to deviate from the original designs will be made to wrench on 20 year old Yugos with Harbor Freight tools in hell. |
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Brian_e  Samba Member

Joined: July 28, 2009 Posts: 3961 Location: Rapid City, South Dakota
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Posted: Sun Jul 06, 2025 11:02 am Post subject: Re: Crank center line |
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I usually figure if I am under .005” on the different deck heights, I am doing pretty good. I would probably just rock it the way it is since correcting it will be questionable and expensive.
Brian _________________ So more or less the lazier and stupider you want to be, the nicer quality parts you need to buy.
-Modok
www.type-emotorsports.com
Type E Engine Parts and Supplies
https://type-emotorsports.com/collections/engine-parts |
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Alexander_Monday Samba Member

Joined: November 09, 2007 Posts: 382 Location: Springfield Missouri
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Posted: Sun Jul 06, 2025 11:15 am Post subject: Re: Crank center line |
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Brian_e wrote: |
I usually figure if I am under .005” on the different deck heights, I am doing pretty good. I would probably just rock it the way it is since correcting it will be questionable and expensive.
Brian |
Yep probably negligible, my OCD doesn't like it, but if I got the math correct arcsin(0.0899mm /112mm) = 0.04546 degrees. _________________ Danth’s or Parker’s Law:
“If you have to insist that you've won an internet argument, you've probably lost badly.”
Alexander_Monday->What were the rings gapped at?
bedlamite->Almost enough.
andk5591 wrote: |
The original german engineers have attained sainthood and it is impossible to improve perfection.
Anything that anyone does to deviate from the original designs will be made to wrench on 20 year old Yugos with Harbor Freight tools in hell. |
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Alexander_Monday Samba Member

Joined: November 09, 2007 Posts: 382 Location: Springfield Missouri
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Posted: Sun Jul 06, 2025 11:17 am Post subject: Re: Crank center line |
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BTW, I love your engine stand adapter. _________________ Danth’s or Parker’s Law:
“If you have to insist that you've won an internet argument, you've probably lost badly.”
Alexander_Monday->What were the rings gapped at?
bedlamite->Almost enough.
andk5591 wrote: |
The original german engineers have attained sainthood and it is impossible to improve perfection.
Anything that anyone does to deviate from the original designs will be made to wrench on 20 year old Yugos with Harbor Freight tools in hell. |
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Brian_e  Samba Member

Joined: July 28, 2009 Posts: 3961 Location: Rapid City, South Dakota
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jim martin Samba Member
Joined: January 14, 2004 Posts: 337 Location: Vancouver, BC
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Posted: Sun Jul 06, 2025 10:26 pm Post subject: Re: Crank center line |
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simple .
your 0.10 compression difference .
cc your heads ,take 0.7cc out of 2 of the combustion chambers #1 and 4 .done _________________ B.C's fastest street legal vw , June 2006 Hot VW's feature car 9.81 sec at 145.26mph.
Sponsored by :
LUCAS OIL PRODUCTS http://www.lucasoil.com
KROC head porting services
Dialedinperformance.com
Airspeedparts.com topic http://airspeedparts.com/forums/index.php?topic=914.0
Last edited by jim martin on Mon Jul 07, 2025 10:13 pm; edited 1 time in total |
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modok Samba Member

Joined: October 30, 2009 Posts: 27652 Location: Colorado Springs
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Posted: Sun Jul 06, 2025 10:34 pm Post subject: Re: Crank center line |
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Close enough to work,
for what your doing.
The piston rock will be more than the cylinder tilt, and boost makes rings seat anyway.
But it is near the limit of what I'd call acceptable for a production engine(.001" per 1), and not good enough to be a blueprinted engine by my standards. (.0005" per 1)
I am sure there is a milling machine in your city, or ten,
tho making friends with whoever owns it can be hit or miss.
(I think you could figure out how to run one and set it up easy, if you are halfway to mastering a lathe)
IMO, trimming four cylinders the same is MORE harder and more time consuming than decking a case, well, assuming I make somebody else clean up the mess at least. I'm kinda tired of cleaning engine blocks. It was fun the first few thousand times, but now it's work |
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Alexander_Monday Samba Member

Joined: November 09, 2007 Posts: 382 Location: Springfield Missouri
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Posted: Mon Jul 07, 2025 5:37 am Post subject: Re: Crank center line |
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My lathe is a combo, but the mill part is far from big enough for a case.
Cutting the barrels the same isn't too difficult with the mandrels I made and a DRO.
Main thing with a hobby lathe is making sure to keep the tailpiece aligned, the head stays put once shimmed.
_________________ Danth’s or Parker’s Law:
“If you have to insist that you've won an internet argument, you've probably lost badly.”
Alexander_Monday->What were the rings gapped at?
bedlamite->Almost enough.
andk5591 wrote: |
The original german engineers have attained sainthood and it is impossible to improve perfection.
Anything that anyone does to deviate from the original designs will be made to wrench on 20 year old Yugos with Harbor Freight tools in hell. |
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rugblaster Samba Member
Joined: March 31, 2016 Posts: 1234 Location: San Angelo, Texas
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Posted: Mon Jul 07, 2025 8:45 am Post subject: Re: Crank center line |
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Look at dat shit ^^^^^^^ _________________ '69 Karmy, '69 Camper, Meyers clone, '65 drag bug, 10.78 @ 128 (sold it) '51 Dodge farm truck,
'09 MB E350 '18 MB E400, '65 Plymouth Valiant convertible and a '19 Ford F250 King Ranch (nicer, but dirty, farm truck)
VWoA factory trained line tech 75 till 90 or so
ASE Master Certification
VWoA Assoc. of Quality Technicians inductee (One of 25 in the five state southwest region)
La Confrerie des Chevaliers du Tastevin (San Angelo Chapter)
TCU ......GO FROGS!!!!!! |
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jim martin Samba Member
Joined: January 14, 2004 Posts: 337 Location: Vancouver, BC
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Posted: Tue Jul 08, 2025 8:25 am Post subject: Re: Crank center line |
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Dont take this wrong But this is important step during mock up .and a good reminder for others .
if you are using a dial indicator and getting your piston to top of its travel .use the same piston and cylinder on every case bore - does not matter what the measurement is its a number . record them all . now you have the data to make decisions before the machining begins .
again since you have trimmed the cylinders and i will assume the cylinder tops are at the same height and you are at zero deck , cc your heads and just soften 2 of the combustion chambers .
good luck _________________ B.C's fastest street legal vw , June 2006 Hot VW's feature car 9.81 sec at 145.26mph.
Sponsored by :
LUCAS OIL PRODUCTS http://www.lucasoil.com
KROC head porting services
Dialedinperformance.com
Airspeedparts.com topic http://airspeedparts.com/forums/index.php?topic=914.0 |
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Alexander_Monday Samba Member

Joined: November 09, 2007 Posts: 382 Location: Springfield Missouri
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Posted: Tue Jul 08, 2025 11:25 am Post subject: Re: Crank center line |
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I checked the barrel lengths to be sure they were the same and that the head mating surfaces were even before I cut them down.
I checked the head mating surfaces for even again after cutting them down.
I used a test indicator for TDC which has more precision than my dial indicators, although a dial indicator would have been ok.
I checked CB H beam rod length, main & pin diameter and eccentricity with and without bearings and end & total weight and pin fit after CB balanced them.
The Wiseco pistons are all consistent on pin compression height, although I did have to balance them.
I picked the best rod bearings (all but 3 of 16 measured consistent at 0.06220" 90 degree from parting line) from a full set of King CR 803XPN SBC small journal bearings and cut those down to width using mandrels I 3D printed since the Mahle bearings I got were inconsistent and undersized.
I have a spreadsheet of measurements starting with case main diameters 90 degree and 15 degree to parting line with and without bearings, crank mains & rods diameter, ring gaps, etc etc etc, I even put the crank in the lathe and checked runout.
I built my own cam doctor and profiled all the lobes, unfortunately that was before I decided to go to 2387 and am waiting on Jones Cams to grind another custom cam so will profile it and do all the other measurements.
I could go on, but point is that this time I am striving to build this one the best that I can.
(BTW, if someone decides to use Mike Jones for a custom cam, be aware it is a very long wait and his communication is lacking at best) _________________ Danth’s or Parker’s Law:
“If you have to insist that you've won an internet argument, you've probably lost badly.”
Alexander_Monday->What were the rings gapped at?
bedlamite->Almost enough.
andk5591 wrote: |
The original german engineers have attained sainthood and it is impossible to improve perfection.
Anything that anyone does to deviate from the original designs will be made to wrench on 20 year old Yugos with Harbor Freight tools in hell. |
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Brian_e  Samba Member

Joined: July 28, 2009 Posts: 3961 Location: Rapid City, South Dakota
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Posted: Tue Jul 08, 2025 1:03 pm Post subject: Re: Crank center line |
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Alexander_Monday wrote: |
BTW, if someone decides to use Mike Jones for a custom cam, be aware it is a very long wait and his communication is lacking at best |
This is good to know. Thanks for passing it along, and let us know how it ends up.
Brian _________________ So more or less the lazier and stupider you want to be, the nicer quality parts you need to buy.
-Modok
www.type-emotorsports.com
Type E Engine Parts and Supplies
https://type-emotorsports.com/collections/engine-parts |
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Alexander_Monday Samba Member

Joined: November 09, 2007 Posts: 382 Location: Springfield Missouri
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Posted: Tue Jul 08, 2025 2:23 pm Post subject: Re: Crank center line |
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The profiles of the first cam he sent me look pretty good.
More aggressive opening ramps than the FK profiles but rounder nose and less aggressive closing ramp to set the valves back down at about the same rate as the FK profiles do. _________________ Danth’s or Parker’s Law:
“If you have to insist that you've won an internet argument, you've probably lost badly.”
Alexander_Monday->What were the rings gapped at?
bedlamite->Almost enough.
andk5591 wrote: |
The original german engineers have attained sainthood and it is impossible to improve perfection.
Anything that anyone does to deviate from the original designs will be made to wrench on 20 year old Yugos with Harbor Freight tools in hell. |
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jim martin Samba Member
Joined: January 14, 2004 Posts: 337 Location: Vancouver, BC
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Posted: Tue Jul 08, 2025 3:37 pm Post subject: Re: Crank center line |
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- sorry i live in a world of diagnose, find fault and repair . and hopefully assisting you in your question of centerline /deck height error cause and correction
I apologize i misread your info , 2 PISTONS ARE POSITIVE .0035" ABOVE THE CYLINDER as per your reading of +0.0035"
will have to assume at some point you missed something , which is ok and still its correctable . choices are now.
- re machine case to correct centerline then replace and cut 4 new cylinders. ( most expensive )
- cut 2 pistons and rebalance ( free just your labor )
or shim all cylinder and soften 2 chambers , i have made shims down to .003" , simple and you can as well looks like you are capable ( cheap and simple )
will go with first statement .
'''I checked the barrel lengths to be sure they were the same and that the head mating surfaces were even before I cut them down. ""
-- ok ill stop here i will assume at this point not all 4 positions were checked for piston deck height, only 1 .
because at this point the difference of positive + .0035 " would of been discovered and cylinder trimming would not of been the next step _________________ B.C's fastest street legal vw , June 2006 Hot VW's feature car 9.81 sec at 145.26mph.
Sponsored by :
LUCAS OIL PRODUCTS http://www.lucasoil.com
KROC head porting services
Dialedinperformance.com
Airspeedparts.com topic http://airspeedparts.com/forums/index.php?topic=914.0 |
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Alexander_Monday Samba Member

Joined: November 09, 2007 Posts: 382 Location: Springfield Missouri
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Posted: Tue Jul 08, 2025 5:20 pm Post subject: Re: Crank center line |
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Yes, I made an assumption that they (CB or Autolinea) would have machined the decks off the crank centerline not the case parting line. _________________ Danth’s or Parker’s Law:
“If you have to insist that you've won an internet argument, you've probably lost badly.”
Alexander_Monday->What were the rings gapped at?
bedlamite->Almost enough.
andk5591 wrote: |
The original german engineers have attained sainthood and it is impossible to improve perfection.
Anything that anyone does to deviate from the original designs will be made to wrench on 20 year old Yugos with Harbor Freight tools in hell. |
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RWK Samba Member
Joined: June 24, 2009 Posts: 1609 Location: S.W. MI
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Posted: Wed Jul 09, 2025 5:44 am Post subject: Re: Crank center line |
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This was an aftermarket case, about .004 taper of crank centerline to case split.
Checked it on a surface plate, I shimmed case to get decks parallel to crank.
If you have an indicator stand and test indicator and a power tool table like a table saw, or other flat surface, you can check other parts as well, pics show comparison only just to make sure all are the same, pin heights can be checked this way also, quick and easy.
_________________ 73 Type 181
63 Type 113
63 Type 261- 428 071
62 Type 241-378 025 178 530 |
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Alexander_Monday Samba Member

Joined: November 09, 2007 Posts: 382 Location: Springfield Missouri
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Posted: Sat Jul 12, 2025 1:52 pm Post subject: Re: Crank center line |
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jim martin wrote: |
cut 2 pistons and rebalance ( free just your labor ) |
Done, now all are 0.000" and 386.2g (+- my inexpensive tools tolerances) _________________ Danth’s or Parker’s Law:
“If you have to insist that you've won an internet argument, you've probably lost badly.”
Alexander_Monday->What were the rings gapped at?
bedlamite->Almost enough.
andk5591 wrote: |
The original german engineers have attained sainthood and it is impossible to improve perfection.
Anything that anyone does to deviate from the original designs will be made to wrench on 20 year old Yugos with Harbor Freight tools in hell. |
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jim martin Samba Member
Joined: January 14, 2004 Posts: 337 Location: Vancouver, BC
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Posted: Sat Jul 12, 2025 3:02 pm Post subject: Re: Crank center line |
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Great ! Nice job .
Check that off the list _________________ B.C's fastest street legal vw , June 2006 Hot VW's feature car 9.81 sec at 145.26mph.
Sponsored by :
LUCAS OIL PRODUCTS http://www.lucasoil.com
KROC head porting services
Dialedinperformance.com
Airspeedparts.com topic http://airspeedparts.com/forums/index.php?topic=914.0 |
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