 Fred's 2375 Rebuild Thread |
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| friethmiller |
 Dec 31 2024, 12:12 PM
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#1
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Senior Member  Group: Members Posts: 751 Joined: 10-February 19 From: Austin, TX Member No.: 22,863 Region Association: Southwest Region 
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[A softball question for the Ninja and/or others]
This is the cam card that came with my 2357 engine, which was originally built by Rimco/Fat (long block) a few years ago. Can someone explain why with an intake/exhaust of 448, the lift was only set to 327 degrees? I'm about to rebuild my motor and a lot of focus will be directed at piston "deck clearance" and the valve train geometry that wasn't set correctly. Thanks.  |
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Replies
| technicalninja |
Jan 5 2025, 03:39 PM
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#2
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Advanced Member Group: Members Posts: 2,377 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region
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QUOTE(friethmiller @ Jan 4 2025, 08:18 PM)  (IMG:style_emoticons/default/ninja.gif) Used a digital micrometer on all piston skirts, 90 degrees from and on-level with the pins, and got 95.925 mm (3.7765748 in). Next, I zeroed the dial-bore gauge to 95.925mm on the micrometer (in vise). Tested all cylinders at the 12-6 o’clock position. Got a P to W gap of .0025in - .003in depending on the cylinder. This is for the folks reading along... Fred did something here that ALL machinist do! Beginners almost always check piston with a mic and the bore with an internal dial caliper. They then try to take the difference between two separate tools. Fred zeroed his dial bore gauge to the mic (in a vise! It always takes a vice for me too). He then used the bore gauge to check clearance. He IS using a single tool to determine his measurement! Even a cheap bottom of the line bore gauge is FREAKING ACCURATE when used in this manner. I've had to give this "use one tool for measurements" speech many. many times... Fred did that shit automatically! It's HALF the battle! (IMG:style_emoticons/default/first.gif) (IMG:style_emoticons/default/first.gif) (IMG:style_emoticons/default/first.gif) (IMG:style_emoticons/default/first.gif) The process he used and his uber accurate mic means his .0025-.003 measurements will be stupid close... I believe him and most of the time I wonder "are they measuring correctly?" Now, he did make a beginner mistake... I test the cylinders at all different angles. I don't intentionally choose one clocking. I'll watch my needle to get a feel for the circle. Taper and concentricity (roundness) are very important! If I vary more than .0005, I want to straighten that out. Power honing, on a real machine that holds the stones in a micrometer style base CAN slightly correct taper and out of round. Sprung stones or a berry hone don't correct shit! |
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Posts in this topic
friethmiller Fred's 2375 Rebuild Thread Dec 31 2024, 12:12 PM
technicalninja It's probably showing actual lift of the lobe.... Dec 31 2024, 12:31 PM
friethmiller
It's probably showing actual lift of the lobe... Dec 31 2024, 12:45 PM technicalninja looking again that whole cam card is at .050!
... Dec 31 2024, 12:50 PM friethmiller
looking again that whole cam card is at .050... Dec 31 2024, 01:09 PM technicalninja I'd have to see the cam card on it.
I'd l... Dec 31 2024, 01:38 PM technicalninja Changing cam in a T4 means "all the way down... Dec 31 2024, 02:13 PM friethmiller Ok, I've changed to name of this thread to han... Dec 31 2024, 02:50 PM technicalninja WOW!
Was that engine in the car the time you ... Dec 31 2024, 03:28 PM technicalninja Pics please!
Clean and label all of the split... Dec 31 2024, 03:39 PM friethmiller
Pics please!
Clean and label all of the spli... Dec 31 2024, 04:44 PM friethmiller Engine pics
Tear down:
... Dec 31 2024, 05:39 PM friethmiller More Pics
Camshaft:
[u]Camshaft Bearings:
... Dec 31 2024, 07:06 PM friethmiller More Pics:
Note: any perpendicular marks are from... Dec 31 2024, 07:23 PM friethmiller Crankshaft Journal Measurements:
Note: main jour... Dec 31 2024, 07:51 PM technicalninja Reality check...
I never said anything because it... Jan 1 2025, 10:28 AM friethmiller
Reality check...
I never said anything because i... Jan 1 2025, 11:06 AM technicalninja Are the pistons true flat tops with no valve depre... Jan 1 2025, 11:08 AM friethmiller
Are the pistons true flat tops with no valve depr... Jan 1 2025, 11:19 AM technicalninja I MAY have a close machine shop.
Replacing everyt... Jan 1 2025, 11:28 AM friethmiller Web Cam has a 494 grind with a 1” base circle me... Jan 1 2025, 02:08 PM technicalninja Those might not be JE pistons!
I have 2 new s... Jan 1 2025, 02:24 PM technicalninja Looked at that cam. That wouldn't be my first ... Jan 1 2025, 02:47 PM friethmiller Interesting, I'll take a look here in a bit. ... Jan 1 2025, 03:25 PM technicalninja Flat top 96mm 82 stroke. 593.53 CC swept volume. T... Jan 1 2025, 03:42 PM technicalninja Those ARE Keith Black "silverlines".
Tha... Jan 1 2025, 04:03 PM friethmiller
Those ARE Keith Black "silverlines".
Th... Jan 1 2025, 05:56 PM technicalninja I noticed it almost looks like those have a solid ... Jan 1 2025, 04:14 PM Jack Standz Just some thoughts and first impressions.
Thos... Jan 1 2025, 04:56 PM friethmiller
Just some thoughts and first impressions.
Tho... Jan 1 2025, 06:08 PM Jack Standz Since you're rebuilding the motor, let me sup... Jan 1 2025, 05:20 PM friethmiller 9.7:1 Compression Ratio. Damn! That is hot... Jan 1 2025, 06:20 PM technicalninja Intake and exhaust are fine, should support deep i... Jan 1 2025, 07:25 PM technicalninja The pinning is not a big deal.
Needs to be done o... Jan 1 2025, 07:33 PM friethmiller Going to cc the heads first. I measured the ID of... Jan 2 2025, 08:56 AM technicalninja The above looks good.
Easier to see the bubbles i... Jan 2 2025, 09:23 AM technicalninja These might help.
https://www.amazon.com/ABN-Cyli... Jan 2 2025, 09:26 AM friethmiller
These might help.
https://www.amazon.com/ABN-Cyl... Jan 2 2025, 09:44 AM Jack Standz If/when you get around to ceracoating things, as t... Jan 2 2025, 09:29 AM friethmiller
If/when you get around to ceracoating things, as ... Jan 2 2025, 09:46 AM technicalninja
If/when you get around to ceracoating things, as... Jan 2 2025, 09:55 AM VaccaRabite I've got some opinions here.
Remember that ... Jan 2 2025, 10:09 AM friethmiller
I've got some opinions here.
...
Zach
Z... Jan 2 2025, 11:21 AM technicalninja
I've got some opinions here.
Remember that... Jan 2 2025, 01:49 PM cgnj Falcor75 2270 made 158 to the wheels with 10:1, 86... Jan 2 2025, 02:24 PM friethmiller
Falcor75 2270 made 158 to the wheels with 10:1, 8... Jan 2 2025, 03:16 PM friethmiller Ok, Cylinder test via antifreeze titration says 60... Jan 2 2025, 03:22 PM friethmiller @technicalninja - Initial look at deck height her... Jan 2 2025, 09:14 PM friethmiller BTW. I’ll put the head stud back and tighten it... Jan 2 2025, 09:57 PM technicalninja Normal quench, .040"thick,96mm bore is 7.2 cc... Jan 2 2025, 10:10 PM friethmiller
Did FAT supply those pistons?
Yes, crank, cam, ... Jan 2 2025, 10:19 PM technicalninja I don't remember what gauges you had...
Minim... Jan 2 2025, 10:32 PM Jack Standz VaccaRabite made several good points about the CR.... Jan 3 2025, 12:17 AM friethmiller Thanks guys! My head is starting to spin here... Jan 3 2025, 08:56 AM technicalninja I'd go option 1.
JE does offer coatings done ... Jan 3 2025, 09:17 AM technicalninja I'd want the cam and its stuff to map out valv... Jan 3 2025, 09:32 AM friethmiller
Did you verify total stroke?
Need to compare CD... Jan 3 2025, 09:56 AM technicalninja Yep, how far down +/- deck height.
Dial caliper w... Jan 3 2025, 10:14 AM technicalninja At this "level" of engine I'd expect... Jan 3 2025, 10:23 AM friethmiller
At this "level" of engine I'd expec... Jan 3 2025, 10:32 AM friethmiller Ok :ninja: , I used the two shims under the #1 jug... Jan 3 2025, 11:02 AM friethmiller Ok, my 1.7L rocker arms do NOT have elephant feet.... Jan 3 2025, 11:26 AM technicalninja https://aapistons.com/collections/porsche-p...ston... Jan 3 2025, 11:45 AM friethmiller
https://aapistons.com/collections/porsche-p...sto... Jan 3 2025, 12:05 PM cgnj @[url=http://www.914world.com/bbs2/index.php?showu... Jan 3 2025, 12:59 PM friethmiller
[b]@[url=http://www.914world.com/bbs2/index.php?s... Jan 3 2025, 01:19 PM densible1 I had EMS http://www.europeanmotorworks.com do the... Jan 3 2025, 01:31 PM technicalninja Check with Eric @ Automotive Machine.
https://www... Jan 3 2025, 02:48 PM technicalninja And, if I could, I'd pattern the cam I chose o... Jan 3 2025, 02:56 PM friethmiller Thanks Rick,
I'll take my case and crank (+ ... Jan 3 2025, 03:17 PM burton73 @ friethmiller
I just spent a bit of time with Ma... Jan 3 2025, 03:30 PM densible1 @[url=http://www.914world.com/bbs2/index.php?showu... Jan 3 2025, 04:09 PM friethmiller
@[url=http://www.914world.com/bbs2/index.php?show... Jan 4 2025, 07:40 AM burton73
[quote name='densible1' post='3184740' date='Jan ... Jan 4 2025, 02:07 PM Montreal914 I am very far from being an expert but I did a lot... Jan 3 2025, 04:09 PM friethmiller
I am very far from being an expert but I did a lo... Jan 3 2025, 11:11 PM technicalninja That RAT engine used those same KBs and a big cam.... Jan 3 2025, 05:58 PM cgnj @Montreal914 [b]@[url=http://www.914world.com/bb... Jan 3 2025, 06:55 PM friethmiller
I have 3 cases that I'm going to drop off soo... Jan 4 2025, 05:51 AM technicalninja It would be useful to have the shim measurements.
... Jan 3 2025, 09:10 PM friethmiller
It would be useful to have the shim measurements.... Jan 3 2025, 10:25 PM Montreal914 2270 = 78.4 x 96mm
2258 = 78 x 96mm
78.4 cranks w... Jan 4 2025, 09:16 AM cgnj Since we are all spending your money, oil spray gr... Jan 4 2025, 11:19 AM friethmiller
Since we are all spending your money, oil spray g... Jan 6 2025, 01:59 PM technicalninja
[quote name='technicalninja' post='3184830' date=... Jan 4 2025, 11:32 AM technicalninja I would LOVE to know why the pics don't post o... Jan 4 2025, 02:55 PM Superhawk996 100mm
Jan 4 2025, 03:37 PM technicalninja At this level of build I would be hunting thermal ... Jan 4 2025, 03:45 PM technicalninja Thanks SH!
Look at how thick the walls are. T... Jan 4 2025, 04:01 PM technicalninja Need P-W clearance. If they "sized for forged... Jan 4 2025, 04:24 PM friethmiller Just got back in from welding on the front cross p... Jan 4 2025, 04:42 PM technicalninja and yet another thought...
I slipped a set of sto... Jan 4 2025, 05:05 PM friethmiller :ninja: Used a digital micrometer on all piston sk... Jan 4 2025, 08:18 PM technicalninja You need to be halfway down the skirt, below the p... Jan 4 2025, 08:32 PM friethmiller
You need to be halfway down the skirt, below the ... Jan 4 2025, 09:13 PM technicalninja That range is GREAT!
It almost looks like a .... Jan 5 2025, 12:04 AM technicalninja You have accurate tools.
You measured close to .... Jan 5 2025, 12:25 AM friethmiller
You have accurate tools.
You measured close to ... Jan 5 2025, 10:20 AM technicalninja It's both the sight and the feel in tenths...
... Jan 5 2025, 01:43 PM |
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