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Discussion Starter #1
Is there any such thing as an idiot-proof performance build for a B20F?

Something along the lines of a range of target HP bands and the associated list of parts and machining required, etc?

I'm probably going to pull mine to do a proper restoration of my 73 ES and rebuild it while it's out. This will be my first engine rebuild and my goal will be to boost the HP moderately (??130-150??), maintain stock FI, and have a stable and reliable engine.

I'm looking for a kit-type approach along the lines of
-Disassemble your engine
-Tell your machinist to do a, b, and c
-Buy these parts, and
-Follow the green book to reassemble your engine.

Fantasy world?
 

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Discussion Starter #5
You will not be the first or the last to put $10,000 into a B20 rebuild.

George Dill
Well THAT ain't gonna happen! I won't be putting $10K into the entire build. So far I'm $165 into it (used battery, 10 feet of yet-to-be-used FI hose, and a trade of some parts to Volvoracer in partial payment for 2 full rear quarter skins.

Probably best that I don't start a spreadsheet though. I hear that's very bad for morale and marriages.
 

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The big trick is getting the head to flow much better than it does, and head porting is as much an art as it is a science. It's counter-intuitive, and much of what you'd expect to work actually makes it flow worse. On my heads, we're welding up the exhaust ports and then carving them out very differently from how Volvo had them. The ports end up smaller overall, but they flow much, much better than stock. Short of doing that, they can be improved a fair amount, but it has to be done by a guy with the equipemtn and experience to do it. It doesn't have to be a Volvo specialist for basic port work.

The second step is to have the block milled down to bring the pistons closer to the head. This increases combustion efficiency -- the engine needs less ignition advance, and you can run higher compression without pinging.

There are no magic parts that go in or on an engine that do much of anything good. If you want to keep the stock injection, keep the stock cam -- it's tuned to that. There are no headers that beat the stock manifold and head pipes at anywhere near the stock cam duration.
 

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Discussion Starter #8
Have you confirmed that the B20 is in rebuildable condition?

George Dill
Not yet.

Hope to free it up in the coming weeks. Going to apply PB and let it sit for a while and then try rocking it with the car in gear.

If that doesn't work I'll probably pull the head, look around, and take some pictures.
 

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Discussion Starter #9
The big trick is getting the head to flow much better than it does, and head porting is as much an art as it is a science. It's counter-intuitive, and much of what you'd expect to work actually makes it flow worse. On my heads, we're welding up the exhaust ports and then carving them out very differently from how Volvo had them. The ports end up smaller overall, but they flow much, much better than stock. Short of doing that, they can be improved a fair amount, but it has to be done by a guy with the equipemtn and experience to do it. It doesn't have to be a Volvo specialist for basic port work.

The second step is to have the block milled down to bring the pistons closer to the head. This increases combustion efficiency -- the engine needs less ignition advance, and you can run higher compression without pinging.

There are no magic parts that go in or on an engine that do much of anything good. If you want to keep the stock injection, keep the stock cam -- it's tuned to that. There are no headers that beat the stock manifold and head pipes at anywhere near the stock cam duration.
Thanks Phil! Do you offer the ported heads as individual items?
 

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Can't, sorry. At least not for now. All the heads I can get done are committed to engine builds I'm doing for customers, and I have a backlog. It's mostly the heads that cause the backlog...
 

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Discussion Starter #11
Can't, sorry. At least not for now. All the heads I can get done are committed to engine builds I'm doing for customers, and I have a backlog. It's mostly the heads that cause the backlog...
Understand. Well, I'm over a year away from facing decisions on the engine anyway. I've got your site bookmarked (thanks to George for passing the link to me) and have been salivating at the various engine offerings.
 

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Philosophical rant:
"Is there any such thing as an idiot-proof performance build for a B20F?"
As our friends at IPD and also Phil Singher has so often told us, "NO!"
You cannot make anything truly foolproof because fools are so cunning.
In the Navy to build anything truly foolproof it must be at least sea level ocean depth in all three dimensions so that even if the swabs do manage to get it overboard it will still be visible where it went in. That in itself is a tough one. In the Army, if it can be blown in place, there may not be enough evidence that it ever existed. In the Air Force things get lost, boxes get jettisonned to lighhten cargo aircraft but what comes out comes down and may yet be incriminating. I knew a guy getting out of the army that had some stuff in his returning {customs approved} hold baggage or household goods and the inspectors started reading the papers and examining the stuff and it wasn't long before they came to see him.

Further, we know Jesus came not to judge but that we might have LIFE and have it abundantly. But the authorities recognized that too much abundance and too much freedom was about to upset their official applecart insofar as their ability to manipullate the population through their incredibly complex regulations (sound familiar?) so they got one of His guys to finger Him. We don't know what was in his mind - Maybe he wanted Jesus to reveal Himsel as God. But at least at that moment He didn't, at least not the way Judas planned, so Judas saw the error of his way and tried to return the money. When they refused to take it (since it was "blood money"
He threw it on the floor, 30 shekels, the price of a slave, and it was used to buy a cemetery for the indigent.

This has turned into a downer and was not meant to be so,having happened on the eve of the most glorious Christian holiday. But it does show that in spite of careful planning, not givinng full consideration to ALL parameters can certainly leave you with a different outcome than you expected.

Please direct all negative comments to me offlist. And regardless of how it may appear to you, I love you ALL!
 
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