ZPI Racing Stage 1 Head Package for the Scion tC
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ZPI Racing Stage 1 Head Package for the Scion tC
Zero Point Industries a leader in the Subaru arena has now taken what they have learned at building Subaru and applied it to the tC. With many new products to come from Zero Point and the ZPI Racing product line in the next few months.
This is their Stage 1 head package currently offered for the tC. The stock head was found to be very restrictive the Stage 1 head flows 38% better on our flow bench than the stock head. This is with retaining stock valves you can expect an even more significant gain as Stage 2 and 3 become available later in the spring.
click the link to read the rest of the article;
http://www.tctunerz.com/article-zone...-scion-tc.html
This is their Stage 1 head package currently offered for the tC. The stock head was found to be very restrictive the Stage 1 head flows 38% better on our flow bench than the stock head. This is with retaining stock valves you can expect an even more significant gain as Stage 2 and 3 become available later in the spring.
click the link to read the rest of the article;
http://www.tctunerz.com/article-zone...-scion-tc.html
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"The intake and exhaust are port matched the whole head is ported and polished the valves are reworked to our confidential specs. The greatest thing about this mod is that the dealership will never know if you have to take it in for a warranty issue. "
Im not really familiar with these terms, if you could explain, or link me to a page that could explain port matching, and ported/polished heads, that would be great. Also, how could it be that the dealership wouldn't know this has been done. If a machanic has seen hundreds of these engines(b/c it is the same engine shared with the camry), dont you think he'll pick up these changes that have been done?
Im not really familiar with these terms, if you could explain, or link me to a page that could explain port matching, and ported/polished heads, that would be great. Also, how could it be that the dealership wouldn't know this has been done. If a machanic has seen hundreds of these engines(b/c it is the same engine shared with the camry), dont you think he'll pick up these changes that have been done?
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Wow 30 HP for stage 1 wonder how much Stage 2 or 3 will have? even if stage three is only 50hp its probably not gonna be more than 1200 which is a lot cheaper than the S/C but having both oooh the possibilities only if I could afford both 
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Originally Posted by tckurt
Wow 30 HP for stage 1 wonder how much Stage 2 or 3 will have? even if stage three is only 50hp its probably not gonna be more than 1200 which is a lot cheaper than the S/C but having both oooh the possibilities only if I could afford both
Who knows though, but either way, I have thought of the tC needed much better top end, and this mod should help. We shall see once the dyno's are released.
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Originally Posted by niguels
I want to see a dyno too. How does Torque and HP do behave across the powerband compared to the stock unit?
Factual data will be appreciated
Factual data will be appreciated
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Originally Posted by Joe@Dezod
You will have to get some fuel adjustments made to compensate for the added airflow. Headers that are port matched to the exhaust ports on the head will also be ideal in getting out as much air as possible, with minimal turbulance.
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Originally Posted by kutsuju_dj
you will be the first one to blow up your engine 
na for real though..... if your running nos and considering this, you should seriously consider having it profesionally done........
na for real though..... if your running nos and considering this, you should seriously consider having it profesionally done........
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From: Kaska, PA
Originally Posted by jrv2000
"The intake and exhaust are port matched the whole head is ported and polished the valves are reworked to our confidential specs. The greatest thing about this mod is that the dealership will never know if you have to take it in for a warranty issue. "
Im not really familiar with these terms, if you could explain, or link me to a page that could explain port matching, and ported/polished heads, that would be great. Also, how could it be that the dealership wouldn't know this has been done. If a machanic has seen hundreds of these engines(b/c it is the same engine shared with the camry), dont you think he'll pick up these changes that have been done?
Im not really familiar with these terms, if you could explain, or link me to a page that could explain port matching, and ported/polished heads, that would be great. Also, how could it be that the dealership wouldn't know this has been done. If a machanic has seen hundreds of these engines(b/c it is the same engine shared with the camry), dont you think he'll pick up these changes that have been done?
Exhaust Port matching means removing extra material from the cylinder head were the exhaust manifold bolts to the head. Intake Port matching means removing extra material from the cylinder head were the intake manifold bolts to the head. Normally material at these openings would be removed to allow a smoother entrance of air and exhaust gasses in and out of the head.
Porting & polishing is a continuing of portmatching to the head from the opening of the port to the valve the entire port is ground smooth and polished (look at the picture) that allows even more free flow of gasses.
Clyinder head work is for a machinist that really knows what he's doing. Hours and hours of R&D to find the right balance of how much Air the engine can consume and how fast it can get the air out.
A dyno sheet will help show how the modifications will help or hurt the performance of your engine.
Modifications are designed for a specific RPM range. If this machine work is for High RPM it will more than likely hurt low RPM torque and horsepower driveability and fuel economy. Before considering any engine mod you have to be honest with yourself is that the engine RPM that I normally run my motor at.
For me I'd like to find some mods that would help out below the 4500 RPM most of my driving is just cruising back and forth to work.
finding 30 or 40 horse at 7000 RPM might just turn my 33MPG slug into a 20MPG slower slug.
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If you take it into the dealer with and engine problem and they have to open it up to see what happened to cause your engine problem the mechanic WILL know that that is not a stock head. Warranty VOID.
BTW I metioned 33MPG in previous post I was thinking of my XB. My Wife's TC is getting 29 but you understand my point.
Vince
BTW I metioned 33MPG in previous post I was thinking of my XB. My Wife's TC is getting 29 but you understand my point.
Vince
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Originally Posted by Hippy
Originally Posted by jrv2000
"The intake and exhaust are port matched the whole head is ported and polished the valves are reworked to our confidential specs. The greatest thing about this mod is that the dealership will never know if you have to take it in for a warranty issue. "
Im not really familiar with these terms, if you could explain, or link me to a page that could explain port matching, and ported/polished heads, that would be great. Also, how could it be that the dealership wouldn't know this has been done. If a machanic has seen hundreds of these engines(b/c it is the same engine shared with the camry), dont you think he'll pick up these changes that have been done?
Im not really familiar with these terms, if you could explain, or link me to a page that could explain port matching, and ported/polished heads, that would be great. Also, how could it be that the dealership wouldn't know this has been done. If a machanic has seen hundreds of these engines(b/c it is the same engine shared with the camry), dont you think he'll pick up these changes that have been done?
During the manufacturing process of the clylinder head casting rough surfaces exist thoughout the heads. The head is machined so that valve guides and valves seat correctly.
Exhaust Port matching means removing extra material from the cylinder head were the exhaust manifold bolts to the head. Intake Port matching means removing extra material from the cylinder head were the intake manifold bolts to the head. Normally material at these openings would be removed to allow a smoother entrance of air and exhaust gasses in and out of the head.
Porting & polishing is a continuing of portmatching to the head from the opening of the port to the valve the entire port is ground smooth and polished (look at the picture) that allows even more free flow of gasses.
Clyinder head work is for a machinist that really knows what he's doing. Hours and hours of R&D to find the right balance of how much Air the engine can consume and how fast it can get the air out.
A dyno sheet will help show how the modifications will help or hurt the performance of your engine.
Modifications are designed for a specific RPM range. If this machine work is for High RPM it will more than likely hurt low RPM torque and horsepower driveability and fuel economy. Before considering any engine mod you have to be honest with yourself is that the engine RPM that I normally run my motor at.
For me I'd like to find some mods that would help out below the 4500 RPM most of my driving is just cruising back and forth to work.
finding 30 or 40 horse at 7000 RPM might just turn my 33MPG slug into a 20MPG slower slug.
