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Redline Racer
 
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Join Date: Jan 2007
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Volume 1, page 13-20. Make sure you go backwards for loosening and loosen each a little at a time. Take the small bots out first. They aren't really critical as far as removal sequence goes.

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1987 silver 924S made it to 225k mi! Sent to the big garage in the sky

Last edited by HondaDustR; 03-06-2011 at 08:59 PM..
Old 03-06-2011, 08:57 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #81 (permalink)
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I got my water pump at Zim's Autotechnik. They're reasonably priced, have a good reputation, and sell an inexpensive bolt kit. I have over 12000 miles on my pump so far...
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Old 03-06-2011, 09:57 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #82 (permalink)
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Thanks for the advice... those Waterpump options are definitely in my budget

the block is bare now.. nothing left to remove

I found a good machine shop in Thomasville, NC. Gonna take the block to them probably next week to be hot tanked and have the cylinders relapped... thats gonna cost me less than $100 bux

But I also need to bring my pistons, rods, and crank to be worked a little... i may do that in the 2nd machine shop session, I still need to get some numbers for them and such... what exactly do they measure/balance with the crank, rods and pistons?
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Old 03-10-2011, 01:44 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #83 (permalink)
Redline Racer
 
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They should measure the crank main and rod journals for wear and taper, measure the crank for straightness, measure the rod big end bores for out of round, measure the pistons for excess wear, out of round, and taper, and the same with the cylinders. You could also have them measure the main bearing bores for alignment and roundness, but there's not really a whole lot you can do about it if it's off, since there's only one set of undersize bearings and they are the same outer diameter as std. They are not likely to be bad, though. Also have the piston pins and their bores in the piston measured, as well as the small end of the rods. All of this so you don't end up building with worn or damaged parts. Bring along a printout of the clearances and specs so they know what stuff is supposed to be. My shop did not have them on hand.

As for balancing, they will want the entire bottom end reciprocating assembly, meaning the flywheel, pressure plate, and all of the front pulleys, spacers, etc. in addition to the internals. They balance the crank by drilling into the counterweights to make it balanced all the way up and down the length of the crank. They measure oscillations at each end and remove material to balance it out. YouTube - 502 Crankshaft Balancing.wmv The V8 crank needs bob weights to compensate for the piston/rod equivalent weights, which is complicated to figure out and requires balancing the pistons and rods first. The inline 4cyl is much easier since all of the mass is evenly offset and can be balanced straightaway. Once the crank is balanced, they start bolting stuff on one at a time and balancing each part separately so the whole rotating assembly is balanced, and so that if you ever had to replace the flywheel or a drive pulley, it won't upset the balance of everything else and the replacement can be balanced by itself.

The pistons are fairly straightforward. They just weigh them all, find the lightest one, and remove metal from the squarish pads underneath on the pin bosses to match the others to the lightest one. Rods are a bit more compicated, since the whole thing travels up and down, but the big ends also revolve, so they have to be worked so they present equal masses while travelling up and down the cylinder and at the same time have the big ends balance each other out for the side to side part of the rotational motion. The rods have "balancing pads" on each end to provide extra metal to remove. YouTube - Connecting Rod Balancing


The left was the lightest and the rest were ground to match.


#3 was the lightest and #4 was the heaviest.

5 grams doesn't sound like much, but it is at 6500 rpm. Your bearings will last longer and there will be less wasted power if there is any significant out of balance, especially given how much more the 16v likes high revs.
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1987 silver 924S made it to 225k mi! Sent to the big garage in the sky
Old 03-11-2011, 09:25 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #84 (permalink)
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