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Old 07-31-2020, 10:16 PM   #1
Marvelous3
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Default A big valve 8valve is better than a 16valve head for 99% of tbricks

Change my mind.
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Old 07-31-2020, 10:32 PM   #2
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No, you are correct. Especially if you port the crap out of it and gasket match.
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Old 08-01-2020, 05:14 AM   #3
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Stainless steel exh valves are great!
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Old 08-01-2020, 06:44 AM   #4
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My 531 is under construction. Only minor finishing on intake side and 38 exhaust valves. Good for 400 hp says the headmaster. Said also if using around 12 mm valve lift, 44 mm intake valves are fine.
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Old 08-01-2020, 06:55 AM   #5
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Originally Posted by 2turbotoys View Post
No, you are correct. Especially if you port the crap out of it and gasket match.
Why would you ruin the flow by gasket matching?
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Old 08-01-2020, 06:57 AM   #6
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Quote:
Originally Posted by Marvelous3 View Post
Change my mind.
You are correct. I see a lot of abandoned 16v swaps. Had they stuck with 8v that would more than meet the power goals there is a good chance the build could have been completed
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Old 08-01-2020, 10:52 AM   #7
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Wrong. A cylinder head with better flow characteristics is ALWAYS better. If you had said "A big valve 8valve is better than a 16valve head for 99% of TbrickERS", then I'd be forced to agree.

It's like saying you didn't want to date the super-hot, super-nice chick because she was too high maintenance. Maybe it was just maintenance you couldn't do.
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Old 08-01-2020, 07:47 PM   #8
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Hmmm isnt a bigger valve, ported 8v still cheaper than a 16v swap?
NA set up 16v all day, way more power under the curve.
Turbo Meh splitting hairs at that point. 16v make more but at what expense?

Now if the 8v was casted with a decent port shape, combustion shape, this would all change....
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Old 08-01-2020, 08:03 PM   #9
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Why would you ruin the flow by gasket matching?
Lol
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Old 08-01-2020, 08:26 PM   #10
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Wrong.

It's like saying you didn't want to date the super-hot, super-nice chick because she was too high maintenance.
Yes but she is known to often be a tease where the fat bird is know to always put out
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Old 08-01-2020, 08:58 PM   #11
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I kinda wish I could make my valves smaller or add some sort of fins/grooves to them

So for me yeah I think 8V > big 8V > 16V
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Old 08-01-2020, 09:12 PM   #12
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Why would you ruin the flow by gasket matching?
Does gasket matching mean making sure the intake and exhaust gaskets have the same internal diameter of the valves?
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Old 08-01-2020, 09:14 PM   #13
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I think a well ported stock valve head would work for 95% of tbrickers.
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Old 08-02-2020, 02:06 AM   #14
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spend the money on a real turbocharger instead
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Old 08-02-2020, 02:38 AM   #15
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Certainly more than adequate for me, I also prefer the 8v sound. Call me a weirdo. IDK I'm not smart enough to argue the details. 16v does have its own inexplicable cool factor.
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Old 08-02-2020, 04:31 AM   #16
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A 16v can use shorter duration cams so will have better mid range power and still match a 8v top end power, that’s the advantage I think of a 16v engine over a 8v.
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Old 08-02-2020, 05:25 AM   #17
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Does gasket matching mean making sure the intake and exhaust gaskets have the same internal diameter of the valves?
No gasket matching is grinding the ports out so they are the same size as the gaskets. All it does is slow the gas speeds. The throat is not where there is any restriction in the head but around the valve stem is where the work is needed
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Old 08-02-2020, 05:27 AM   #18
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A 16v can use shorter duration cams so will have better mid range power and still match a 8v top end power, thatís the advantage I think of a 16v engine over a 8v.
Yes that is the advantage but you do loose torque and engine braking with a 16v. David Vizard has come up with the polyquad head that increases swirl and tumble to improve torque. Never see it done with a Volvo head and how much gain you get is a ?????
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Old 08-02-2020, 08:13 AM   #19
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Yes but she is known to often be a tease where the fat bird is know to always put out
Well played, sir.
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Old 08-02-2020, 10:09 AM   #20
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Originally Posted by shoestring View Post
Wrong. A cylinder head with better flow characteristics is ALWAYS better. If you had said "A big valve 8valve is better than a 16valve head for 99% of TbrickERS", then I'd be forced to agree.

It's like saying you didn't want to date the super-hot, super-nice chick because she was too high maintenance. Maybe it was just maintenance you couldn't do.
Right. You wine and dine her. Treat her nice. Then take her home to find out the tits are fake and that big bush isnít the Brazilian that was advertised.
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Old 08-02-2020, 02:10 PM   #21
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Damn! You guys gettin' nasty...
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Old 08-02-2020, 02:50 PM   #22
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Actually turns out to has a huge big c*ck
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Old 08-02-2020, 04:53 PM   #23
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Well, I've been running a flowed 405 with stock valves for a long time. It revs easily to 7k or more if you wanted to and runs better from off idle to redline than when I ran the engine with a stock head.

I think the 405 with flow work or any stock 8v head with work would easily satisfy most power goals for a fun street car while keeping it 8v simple.
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Old 08-02-2020, 06:23 PM   #24
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Are we talking pure performance or driveability as well?

At the same power level, wouldn't a 16v have better street manners than an 8v?
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Old 08-02-2020, 06:52 PM   #25
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Are we talking pure performance or driveability as well?

At the same power level, wouldn't a 16v have better street manners than an 8v?
yeah pretty much. the issue is not so much one of head choice but relative tuning ability. it is not limited to 16v cars either lol.

a better way might be to say "you'll have best results when you do not exceed your abilities as a mechanic", but then if you never try new things you'll never learn anything either.
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