I've been bitten by the stroker bug.
#211
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Last edited by Bigfoot928; 05-24-2020 at 03:26 PM.
#212
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#213
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Last edited by Bigfoot928; 05-24-2020 at 03:27 PM.
#214
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I've never seen welding on the face of a 928 head cause warping of the cam journals. They are pretty sizable heads. I'd look very close at the cam caps. I took one 928 engine apart that the cam caps were not in the numbered locations. I tried putting them back and had the same issue. I was glad I noted which numbers were swapped.
#215
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To preserve the factory bore alignment it is critical that the caps go back in the same place where they were originally bored. You mentioned a missing sleeve on #8, those are the dowels that locate the caps and are critical.
A different sleeve may not be quite the same. I would check it carefully, make sure it is not bent or distorted in any way.
Also two of the caps in your picture above don't appear to be numbered-- #1 and #3. Are you sure they are in the right place? (Yes, those are not the ones that are binding, but maybe things got mixed up in the past).
Do you have a set of Porsche cams that you can try on this head?
If you can get your hands on a good mic I would measure those as well as the Web cams, and see where you are at, journal-wise. (1-2" micrometer, not a caliper). Your machinist can easily do that for you.
Suggestion: Take tomorrow off and enjoy the holiday!
#216
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What's a holiday?
So, I did some more testing. While the exhaust cam is the the 87 head and no caps are in place I placed a 30mm wrench on it, held it at 45 degrees. It will drop as soon as I reduce the effort hold it up. Place the same cam in the 89 head and the wrench remains in place and does not move once I remove my hand.
So, I did some more testing. While the exhaust cam is the the 87 head and no caps are in place I placed a 30mm wrench on it, held it at 45 degrees. It will drop as soon as I reduce the effort hold it up. Place the same cam in the 89 head and the wrench remains in place and does not move once I remove my hand.
#217
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Off comes head and then off to Allied to be line bored. They have a 28mm cutter.
I need to keep a list of everything I've done wrong - quite a list.
I need to keep a list of everything I've done wrong - quite a list.
#218
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Last edited by Bigfoot928; 05-24-2020 at 03:27 PM.
#219
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#221
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That is what we will know shortly. When I pull the head and place the cams back in the head we'll know more. This is uncharted territory for me.
Allied is to go to machine shop in the Southeast. Among the bunch of other mistakes I have made was not providing cams and caps to Allied. So, this is on me.
My other stroker adventures were different. Both of the engines were built by shops that built drag racing engines. The first was a '65 VW I had stroked to 1874cc(?) built by a VW drag racing shop on Long Island. Had dual solexes and all kinds of suspension changes to eliminate wheel hop. Monstrous wheels and tires. That was the Thunderbug. The bug would beat Kawasaki 750s and even my friend's 914-6 off the line. Toyed with a couple good ole boys in a Nova along I95 in CT. Speedo stops at 90 and it was beyond pegged. According the guys in the Nova we we doing in excess of 110. The second adventure was 1977 HD Cafe Racer. Ran into a fellow that built drag racing motorcycles in B'ham. Saw the Cafe Racer without heads leaning against the wall in his shop. Asked if it was for sale and he said yes. He asked if I wanted it stock or stroked. I chose stroked. That motorcycle was a rocket - pure and simple. No kick start so George had to regear the starter. Ran on racing fuel. Ruined me for all other motorcycles I owned. I miss them both something awful.
Allied is to go to machine shop in the Southeast. Among the bunch of other mistakes I have made was not providing cams and caps to Allied. So, this is on me.
My other stroker adventures were different. Both of the engines were built by shops that built drag racing engines. The first was a '65 VW I had stroked to 1874cc(?) built by a VW drag racing shop on Long Island. Had dual solexes and all kinds of suspension changes to eliminate wheel hop. Monstrous wheels and tires. That was the Thunderbug. The bug would beat Kawasaki 750s and even my friend's 914-6 off the line. Toyed with a couple good ole boys in a Nova along I95 in CT. Speedo stops at 90 and it was beyond pegged. According the guys in the Nova we we doing in excess of 110. The second adventure was 1977 HD Cafe Racer. Ran into a fellow that built drag racing motorcycles in B'ham. Saw the Cafe Racer without heads leaning against the wall in his shop. Asked if it was for sale and he said yes. He asked if I wanted it stock or stroked. I chose stroked. That motorcycle was a rocket - pure and simple. No kick start so George had to regear the starter. Ran on racing fuel. Ruined me for all other motorcycles I owned. I miss them both something awful.
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Donald Smith (11-30-2022)
#222
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Head is at Allied. $125 to line bore - I assume that is per journal. I'll have it back next Friday.
#223
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Allied called. Head is ready to be picked up. Line bored $138.00 all in.
One of the journals was a different size then the others. My guess it's the #8 journal. Make no sense to me. I'll probe them tomorrow when I pick it up.
One of the journals was a different size then the others. My guess it's the #8 journal. Make no sense to me. I'll probe them tomorrow when I pick it up.
#224
Drifting
Wow. I hope that was the issue. Good luck Kevin.
#225
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As it turns out one of the journals was larger than the others. They broke down the head and cleaned all the oil galleries, etc.
Heads are at my shop. Exhaust cam turns by hand. Intake not so much but it difficult to grab an end like the exhaust cam.. They've plasti-gauged by Allied, but my shop wants their inhouse cam expert (His name is Merlin) to look at them.
Hopefully, we'll back to making forward progress this weekend.
Heads are at my shop. Exhaust cam turns by hand. Intake not so much but it difficult to grab an end like the exhaust cam.. They've plasti-gauged by Allied, but my shop wants their inhouse cam expert (His name is Merlin) to look at them.
Hopefully, we'll back to making forward progress this weekend.