Ranger's Dec09 motor rebuild thread (lol)

#181

keep at it scott… i need to work on my motor refresh soon… less than 8 weeks to the first event.

#182

Did a drip test of Chuck’s head. This is where you invert it and pour something into the combustion chambers like gas, alcohol or acetone. The measure of a good valve jobs is, as I understand it, 3 drips/min past closed valves.

Chuck’s head got 0 drips/min. 0. That beats the crap out the last couple of heads I destroyed. Boys and girls, send your heads to Chuck.

Now, if I can just avoid hurting this nice new head.

#183

Congrats on getting good head, Ranger! I’ve gotmy fingers crossed that the install goes well.

Is the tight seal a function of the valve grind, strong springs, shimmed springs, or something else?

What’s the street price for Chuck’s head refresh?

#184

Tight seal is a function of the valve grind…it should seal with 5# springs.

Prices vary but figure about $550 plus shipping and repair parts. That includes blue printing the cam. If you need rocker shafts, that is extra, etc.

Note…it takes me about 4 weeks to turn a head around…plan accordingly. Chuck

#185

Chuck -

It takes me about 4 weeks to unpack and repack for a track weekend, so your turnaround time seems fine by me. :laugh:

As you know, I don’t know much about engines but I have learned a ton through Ranger’s trials and tribulations.

What makes for such a good seal of the valve? Is it a function of the angles and machining being that much more precise than the typical production line engine?

#186

The one scare yesterday was with the oil pump drive shaft. It flipped out of my fingers as I was under the car installing the oil pump. Laying on the mechanic’s creeper, I looked around but didn’t see it. I then scooted the creeper back about a foot so I could see more realestate. I think that one of the creeper wheels hit the drive shaft when I scooted it back. The driveshaft has two little plastic washers on it. One of them was crunched.

I jumped on E30tech to ask what the plastic washers did and if I could go without one. Then I went hunting thru my somewhat organized and monthly swelling attic spare parts depot, and found an old oil pump drive shaft. To my wife’s confusion I came barreling out of the attic, put the oil pump drive shaft in front of her nose and exclaimed “THANK GOD!”

Later the lads at E30tech.com would inform me that those plastic washers are no big deal.

It turns out that ARP reusable rod bolts are available. $200 from VAC. If I’d a known that earlier I’d a bought them.

#187

Steve D wrote:

A good seal initially will be the result of precision in grinding the valves and seats. How long that “perfect” seal will last has a lot to do with how precisely the guides are done.

#188

Steve D wrote:

:huh:

#189

jlevie wrote:

[quote]
A good seal initially will be the result of precision in grinding the valves and seats. How long that “perfect” seal will last has a lot to do with how precisely the guides are done.[/quote]

I read some interesting stuff at www.BobIsTheOilGuy.com last month re. Marvel Mystery Oil. MMO is an oil AND gas additive that dates back to WW2. The BITOG guys didn’t think much of using it as an oil additive, but were generally favorable towards using MMO as a gas additive.

The reasoning went like this…Apparently modern gasolines are more “dry” then they used to be. I interpret this as having fewer long chain molecules, acheived by better refining controls. The better controls do a good job at removing the molecules that are outside of the designed length for the refined product.

The up-side of better refining control is that you get more “pure” gas. But the downside is that gas has fewer lubricating properties. Long carbon chains molecules lubricate, short carbon chains make good solvents.

Which leads me, finally, to my point…Gas having lubricating properties is apparently important for valve and and valve seat life.

I don’t know any of this first hand, it’s just what I read. Steve Foushee is the gas-man so he may have some interesting thoughts to add.

#190

jlevie wrote:

[quote]Steve D wrote:

A good seal initially will be the result of precision in grinding the valves and seats. How long that “perfect” seal will last has a lot to do with how precisely the guides are done.[/quote]

Seal is nice but isn’t the key to power the mixture, which is more a function of the valve ‘shape’?

#191

IndyJim wrote:

Absolutely. Optimizing the shape of the seats and valves (within the rules) improves mass flow through the engine and thus makes more power. A three angle valve grind is typically use for this purpose.

#192

Power is strictly a product of air flow. After that, everything you do is to optimize the mixture and timing to utilize the air flow. Chuck

#193

jlevie wrote:

Just a reminder for the RacerX’s out there:
9.3.1.2.6. No engine component may be modified in any manner not specifically permitted or authorized by the Factory Service Manual, , or Factory Technical Bulletins.
9.3.1.2.7. Overhaul procedures which in any way may increase performance beyond factory specifications that are not specifically authorized by these regulations are prohibited, (e.g. porting/polishing, etc).

#194

double post…

#195

Gasman wrote:

[quote]Ranger wrote:

[quote]the up-side of better refining control is that you get more “pure” gas. But the downside is that gas has fewer lubricating properties. Long carbon chains molecules lubricate, short carbon chains make good solvents.

Which leads me, finally, to my point…Gas having lubricating properties is apparently important for valve and and valve seat life.

I don’t know any of this first hand, it’s just what I read. Steve Foushee is the gas-man so he may have some interesting thoughts to add.[/quote]

Scott, While I appreciate the vote of confidence, I’m not a chemist, my job is marketing and transportation. Lead was removed as the lubricating agent in gasoline. Logically, I can’t see how vaporized gasoline will lubricate valve stems or why it should for that matter. Diesel fuel on the other hand is a bit different. Lubricity to a diesel engine is much more important and why engine manufacturer’s have had so many problems overcoming the problems with ultra low sulfur diesel. It was the sulfur that provided the lubrication.

It should be noted that adding additives to gasoline is currently a violation of the 2010 rules.[/quote]

#196

[quote]Gasman wrote:While I appreciate the vote of confidence, I’m not a chemist, my job is marketing and transportation. Lead was removed as the lubricating agent in gasoline. Logically, I can’t see how vaporized gasoline will lubricate valve stems or why it should for that matter.

It should be noted that adding additives to gasoline is currently a violation of the 2010 rules.[/quote]

Ok, you’re not a chemist, but you’re still the only person I know that has any insights on the gas industry.

I wasn’t attempting to suggest that we add stuff to our SpecE30 fuel, I know the rules. I just thought that it was an interesting tie in to the issue of valve and valve seat longevity. I added some Marvel Mystery Oil to my DD and tow vehicle.

#197

Ranger , did you pick up some literature from 1974?? whats up Rip van Ranger??

#198

bdigel wrote:

I’m pretty dismissive re. magic elixers, but the boys of bitog really know their stuff. And if they seem agreeable to a product and go into detail on explanations, I’m hesitant to contradict them without reading a good contrary arguement.

I put the head on tonight and fastened the head bolts down to 22ftlbs. I figure that ought to be enough to do compression and leakdown tests, while not compressing the headgasket and making it unre-usable if I find there’s a reason to remove the head again. The tbelt is also on.

The headbolts and the mating surfaces were cleaned with utmost care. One of the holes was sticky so I’m really glad I did a test thread of all the headbolts. I was going to chase the threads in all of the bolt holes but the tap started biting firmly into a hole that threaded perfectly well. That made me nervous so I backed off on that idea.

Tomorrow night it’s compression and leakdown tests. If the tests go poorly I’ll have to tighten the bolts down a bit more.

Thursday I head out to Colorado to spend 4days skiing with the Reverend Al.

#199

Ranger, you do not use a tap to clean threads…you use a thread chaser-major difference.

A note to all. I have been unable to access a factory BMW shop manual and for that reason I have used the Bentley for years with great success. The heads I am doing are not touched in any way in the ports. The original factory finish is evident in all ports flange to valve. I do, however insure the concentricity of the valve guide and the valve and use an industry standard valve grind. All clearances are for racing, not the street, for longevity. Chuck

#200

cwbaader wrote:

[quote]Ranger, you do not use a tap to clean threads…you use a thread chaser-major difference.
[/quote]

Understood. That’s what I as thinking when I decided “hmm, maybe this tap is a bad idea”.

A set of metric thread chasers would be nice. I’ll look around for some.

Later edit. Cheaper then I thought. http://www.amazon.com/Mstc-RC7-Rethreading-Chasers/dp/B000AEX8DW/ref=sr_1_8?ie=UTF8&s=hi&qid=1263999976&sr=8-8