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Discussion Starter · #1 ·
Ok, delving into the heads more...

3 angle or 5 angle grind on the valves? P&P first, or should i have some material shaved. and lots of other stuff that i don't really understand, so if you would be so kind as to fill in the LARGE knowledge gap in my head, i would appreciate it. Here goes what they are doing... and cost is 1900.00 usd.. so also is it worth it?

POCKET PORT
Includes Complete Visual Inspection
Cylinder Head Deburred
Deshrouded Polished Combustion Chambers
Radiused Blend Seats
Check All Surfaces for Straightness
Hand-Lapped Vacuum-Tested Valve Seats
New Valve Seals Extra
Combustion Chambers C.C.'d
Bowl Port & Polish (behind valve seat)
Gasket Match Port & Polish (Intake & Exhaust)

VALVE TRAIN COMPONENTS
Dual Springs
Single Springs
Standard Size Stainless Steal Heat Treated Nitrite Coated Valves
Oversized Valves
Titanium Retainers
Valve Keepers
Spring Seats
Valve Guides

STAGE VI
Pocket Port Plus...
Cylinder Head Blueprinted
Detailed Matched Intake Manifold Fully Ported to Head
Match Port Exhaust Manifolds
Port Faces Lapped Flat (Studs removed and reinstalled)
Decks Milled Lapped (At any amount with no additional charge)
Radiused Cut Seats

and would this help at all in my application? again thanks...

Strip
 

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ok, not sure what you have done already to your tC. but unless you are going with some wild aftermarket cams, you don't really need all that done. also, unless you are FI or completely Built NA with some high compression, you don't really need that done. i would say on a bone stock motor, 2-5 hp increase. you'll notice it in the top end, it may even hurt your performance on a stock motor. with FI you might see 10hp but i doubt it. it'll help you hit boost quicker tho and let you flow more cfm's.

hope that helps you.
 

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Sure is a lot of dough for a quick clean up job and some new valves, springs and retainers that will only allow you to hit the conservative rev limiter quicker. Also unshrouding the valves if needed wil result in a loss of compression (read efficiency).
 

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Discussion Starter · #4 ·
Well, it's a spare head i got, and was gonna see about doing some deck work also. I'd like to push the compression up if i can. Someday, when somebody learns how to change the rev limit, i would like to destroke it a little, maybe sleeve it and bore it a few overbore sizes to make up for the shorter stroke, and then push up the red line.. 7.5k sounds good, but i'd even take 7 as a happy compromise. I had read somewhere, that the valve springs on the 2az are soft, and would/could run into problems when higher rpms are encountered. Also, i think lance would agree, but the air moving through the current head is gonna be anything but smooth. Swirl should be induced in chamber, not enroute. I can't see a smooth boundry layer staying attached with all the burrs in the intake ports.

With aa destroked, but bored cyl. i think the problem may become a volume/speed problem. The total intake time is reduced but the volume remains the same.

If i get this done, i may be able to send lance a few valves/ equipment so he can get it on a flowbench.

So whats better, 3 angle or 5. or is it such a minimal thing that i need not worry?

As a reminder, i dont want FI, i think there is nothin nicer than a high strung NA engine turnin the wheels. I've blown up motors with turbos before, a saab and an airplane. Wasn't supposed to be able to destroy either. Saab didn't like a 4th>2nd downshift, and airplane just wasn't happy at all.
 

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Discussion Starter · #5 ·
Idea's?? the cycle is pullin hard for the money also... sucks having to split it
 

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Originally posted by josurr+Jan 6 2006, 01:00 PM-->QUOTE (josurr @ Jan 6 2006, 01:00 PM)
<!--QuoteBegin-uberingram
@Jan 6 2006, 11:57 AM
Talk to Nick at http://www.nrgyheads.com/
i dont know if hell do the port job... he swore never to work on a scion again after he installed my sway bars... hes still pissed off at you btw... [/b]
That's not Scion's fault. That's yours and Hotchkis' fault.
 

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POCKET PORT - This is a Chevrolet shop if they are talking about pockets, four valve engine ports don't have a classic "pocket" or "bowl", they have a roof, floor, and divider or some guys say a long side and short side
Includes Complete Visual Inspection - yes
Cylinder Head Deburred - maybe, but not a bad thing, mostly for cast iron heads, usually unnecessary with aluminum
Deshrouded Polished Combustion Chambers - There is usually only a tiny amount of shrouding in a four valve per cylinder head, this is pretty pointless.
Radiused Blend Seats - This is a mixture of terms and confusing - Blending the seats is what they mean, the are not radiusing the seats themselves.
Check All Surfaces for Straightness - essential
Hand-Lapped Vacuum-Tested Valve Seats - the worst thing you can do to valve seats and a guaranteed power loss - NEVER lap seats or valves.
New Valve Seals Extra - should be included in the price
Combustion Chambers C.C.'d - a good thing to do, but only if they are adjusting them to within 0.1cc
Bowl Port & Polish (behind valve seat) - four valve ports generally do not have what is described as a bowl because the roof doesn't take a bowl shape - polishing should never be done to an intake, and changing the dimensions - porting - should not be attempted without flow data to confirm the changes are beneficial
Gasket Match Port & Polish (Intake & Exhaust) - another confusing term that has popped up recently - what is going to be matched? The port to the gasket (bad idea) or the gasket to the port?

VALVE TRAIN COMPONENTS
Dual Springs - waste of money for this engine
Single Springs - WTF? Single springs are stock.
Standard Size Stainless Steal Heat Treated Nitrite Coated Valves - waste of money for this engine
Oversized Valves - waste of money for this engine in street use
Titanium Retainers - bad idea for any street engine
Valve Keepers - WTF? Do they mean replacing them with exotic materials? BAD idea for street.
Spring Seats - WTF? Do they mean shimming the spring seat to set the spring compressed length?
Valve Guides - this engine is too new to need new guides

STAGE VI
Pocket Port Plus...
Cylinder Head Blueprinted - without a clear description of exactly what will be done, this statement is meaningless
Detailed Matched Intake Manifold Fully Ported to Head - truly a good thing
Match Port Exhaust Manifolds - truly a good thing
Port Faces Lapped Flat (Studs removed and reinstalled) - not as good a thing as it sounds for the vast majority of applications
Decks Milled Lapped (At any amount with no additional charge) - not as good a thing as it sounds for the vast majority of applications
Radiused Cut Seats - not as good a thing as it sounds for the vast majority of appications, potentially detrimental on the intake side, should be tested on a flowbench to validate.

It's also not generally a good idea to send your head to a specialist in one type of heads expecting the same results. If there is a shop specializing in 2AZ heads, they will likely get better results than a generalist or someone specializing in something else. That said, anyone who claims they can make significantly more power without doing a valve job is not a good source. The cut on the valves and seats means more to a good port job than anything else you do. Anyone suggesting that you can remove the valves from your head and install them on their piece and make significant gains is FOS. There is a LOT to cutting valves and seats, and there is a lot you can do with OEM valves to make them perform like best of breed aftermarket with just a die grinder, drill press, valve facing machine, and about 8 minutes per valve.
 

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Ironhead
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Former '05er
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It's not worth $400 without valves. I can get one from a junkyard for less with valves and springs. That head and cams is worth the same $225 I paid for mine.
 
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