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Old 07-03-2018, 05:24 PM   #26
CRatcliff
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I will check!
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Old 07-03-2018, 05:25 PM   #27
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OK, I lied about checking - I'm still driving the car around, so I can't check that (right?)
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Old 07-03-2018, 05:31 PM   #28
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If you can't get to the flywheel to count the number of bolts check the size of the crank pulley bolt. 6 bolt cranks use a standard bolt with a 13/16" hex. 8 bolt cranks use a metric bolt with a 22mm hex.
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Old 07-03-2018, 05:48 PM   #29
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Sounds good. That will probably happen at the same time as the head comes off and cam changes, correct? Sorry, I'm new to car engines - used to motorbike engines.
So process would be:
1) Figure out what the cam I will be using
2) Depending on cam, figure out compression
3) Decide on whether to deck block or mill head, and get thinner gasket
4) While head is off, figure out if I need the M rods by measuring the size of the crank pulley bolt

Is that correct? Seeing this, the cam is gonna be the blocker at this point. Would love advice on the best way to move forward with it. Head should be done in about a month.
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Old 07-04-2018, 08:12 AM   #30
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Did 8-bolt crank had a different front pulley with holes?
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Old 07-04-2018, 01:33 PM   #31
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I don't think so. Crank pulleys interchange between all B18/B20 engines. The pulley with holes is just an updated part. It first appears in the '67-'72 140 parts catalog
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Old 07-04-2018, 01:49 PM   #32
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Thanks, was there problems with previous design?
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Old 07-04-2018, 02:18 PM   #33
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One can only assume so. The pulley was actually updated twice from 418254 to 460516 to 460783.
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Old 07-05-2018, 03:59 PM   #34
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Jumping back to previous topic - any advice on a cam to use? Not sure what the core needed is for the custom one, but I know it's been hell trying to find one.
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Old 07-05-2018, 04:31 PM   #35
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Quote:
Originally Posted by hiperfauto View Post
The F gasket is .039" compressed.

The B18 rods are notoriously weak. 6 bolt B20 rods are reinforced in the problem area and aren't a problem under 6500 rpm. 8 bolt B20 rods can be swapped for M rods if you don't think they're up to the task.

The rods on my PV's motor had weird little wear(?) marks *right* where that red arrow is pointing. Right on that spot, on both sides of the rod, little lines across the inside of the big end. As far as I can tell, the big end was flexing at that spot, perhaps just a little.



I noticed this the last time I had it apart to replace a piston with a little broken chunk on it.
Flexing big ends on rods didn't seem like a good idea, so I put it back together with another set of B21Ft pistons and a set of B20 rods.
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Old 07-05-2018, 04:32 PM   #36
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Quote:
Originally Posted by CRatcliff View Post
Jumping back to previous topic - any advice on a cam to use? Not sure what the core needed is for the custom one, but I know it's been hell trying to find one.
I've been using an Isky VV81, it is a bit weak below 3000 - 3100 rpm, but it screams past that up to as fast as I dare spin it (7K).
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Old 07-06-2018, 04:27 AM   #37
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Timo's 717 is very nice street cam. A bit oomphier than D or K, can be found from Timo's and Folkraceshop, at least.
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Old 07-06-2018, 09:16 AM   #38
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I've also used factory R and S cams in the past, they were fairly similar to the VV81. A rather 'vintage' feeling performance cam, clearly sacrificing low-end torque to make high-end HP. They both noticeably 'woke up at a certain RPM. I understand that more modern cam profiles can produce less of a tradeoff.

I was going to put a KGTriming KG18 in it once, but they said 3 - 4 months wait, so I moved on.
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Old 07-06-2018, 01:17 PM   #39
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Yeah, Timo 717 was designed around 1984, so that is quite modern for B20!
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Old 07-06-2018, 01:32 PM   #40
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Iskenderian added 3 cam profiles to their lineup of pushrod cams for Volvo a few years ago, the Z series. They are of a newer design and run tighter valve clearances (except for the super competition cam), more lift and less duration. My experience with these cams is that they provide a more tractable power band in the lower rpm range while still making very good power at the top end. They're ground on all new blanks so no core is required.

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Old 07-06-2018, 01:50 PM   #41
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Very interesting. I wonder how that higher lift would work with my KGTrimning roller rockers.
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Old 07-06-2018, 01:55 PM   #42
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Are they a higher ratio than stock? As with any high lift cam, you'd need to check V-P clearance (especially if the head has been milled) and make sure the springs aren't binding.
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Old 07-06-2018, 02:23 PM   #43
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Awesome, thank you! Yeah, those look like a much better option. Biggest thing for me is that I'm not looking to sacrifice low end power - most of what I intend to do is drive around the city, and be able to accelerate into and out of traffic comfortably. Obviously would love to be able to canyon carve as well and have it be a fun road trip car, but I don't want it to be miserable when I'm not doing those things.

I honestly don't understand cam grinds at all, so this would be something that I would take either your advice or John V's on (if John V has one that he would recommend, I'd probably go with that - he has the clearest understanding of the rest of the build!)
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Old 07-08-2018, 12:00 PM   #44
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Bump! I'm hoping to get on getting on a cam tomorrow - already a week into the month of lead time for the head, and once that's up they'll need to know what compression values we're hoping to get, and to know that we'll need to know what cam we're using.

--Colin
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Old 07-08-2018, 12:01 PM   #45
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Also need to know what rate the springs need. I know John V had said 85-90lb before, and I believe that's the unlifted rate?
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Old 07-09-2018, 06:40 PM   #46
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Bumping again!
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Old 07-09-2018, 06:55 PM   #47
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What are your plans for this engine? Is it for a daily driver? What you're going to do with it depends on which cam you choose. Also, larger displacement engines can use more cam.

Isky 625/626 springs have a seat pressure of 98 lbs @ 1.625" installed height.
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Old 07-09-2018, 07:00 PM   #48
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Not necessarily daily driver, but will be driven around the city (date car, I guess?), and road trip car. Want it to be fun to drive on PNW highways (think highway 101 North of SF style). So not something that needs to scream around to be fun, but something that is fun and quick. Engine has first over bore.

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Old 07-09-2018, 07:16 PM   #49
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What are you using for induction, carbs? If so, which ones.
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Old 07-09-2018, 07:18 PM   #50
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Carbs for sure. Trying either Weber or Mikuni. Dual 45s for the Mikunis, four 45s for the Webers.
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