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Super Moderator
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Discussion Starter #1
Gents,

I find myself at an impasse. I've got most of what I need to build a 10:1 3.4L bottom end but at the moment I've got a stock head with a BC valvetrain kit and some Blitz (yes, Blitz) 264* cams for it. It'll be topped off with my Veilside intake manifold and utilize a modified RPS exhaust manifold.

I plan on revving to ~8400rpm or so to stay within the limits of a PHR oil pump. In a perfect world, I'll find myself the HKS T51R BB SPL turbo that I covet and I'll aim for ~1000whp, otherwise it'll likely be a GTX4294R or GTX4202R and I'll make a bit more power.

At this level I know cylinder head porting can make a significant improvement. But there's a lot of awesome names with various porting/cylinder head programs, and I'm at an impasse on deciding who's porting program to go with, whether or not +1mm valves would be worthwhile, etc - or whether I should bother porting it at all.

So anyone that can weigh in with before & after results of porting or an overall cylinder head program with a ~1000whp 3.4L with a similar intake manifold and rev range would be greatly appreciated!
 

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Super Moderator
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Jeff,

I have what you have (VeilSide, 3.4L, etc.), but no before and after data to share. My head work was done when I had a built 3L but, when I went 3.4L, along with bigger turbos, we lost the opportunity for back to back comparisons. My recommendation is velocity-biased head work, with stock sized valves, or no real port work at all, but for some minor clean-up. I know this is not what you want, but it's all I got, bud.

Ken.
 

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Time for change
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You cannot get around resonance tuning, enlarging the port CAN make more power and change where the peak VE is.
But there is a problem. Part of the magic of the Supra making the power it does with it's flow numbers has to do with it's throat convergence. It continues to fill the cylinder very well even after the piston has starting compressing. Most modern cylinder heads do this, the Supra just does it particularly well.
I've seen some FSAE papers and home grown sport bikers actually filling their intake ports, specifically to cause the nozzle effect. It caused flow numbers to drop, but power went up across the powerband. They suspected it had to do with continued cylinder filling longer, even as cylinder pressure was increasing.

So porting on the 2J may not do what we want it to do if we don't have the right combination of cams and intake manifold setup.

However, typically to increase REVS (and make power-not having it fall off) we should consider porting.
 

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Boost Junkie
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I did a lot of research when I did my most recent build and came to the conclusion that unless you are shooting for 1200+whp, it is a waste of $$$ that is better spent elsewhere.

Steve K.
 

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Well, power doesn't exactly mean RPM. It depends on what you want to do. If you want to improve VE without upping boost, then you'll need to port especially when increasing the displacement because you're going to be reaching intake mach stall numbers faster (which is very RPM dependent).
But if you want power, you can make 1000 whp before 8000 rpm for sure. You can just keep upping boost if one wishes without porting. I think that's what 1A1 is saying.

It's up to you, and what you want to do.
 

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^^Yup. Made 1115 whp at 7,200 rpm and 37 psi on C16 back in 2004. At the time, no one, to my knowledge had made more power with less boost (have HKS 272 cams) with a street car. A car built identical to mine, except HKS 280 cams, did 1101 whp at 34 psi (C16), still one of the lowest boost levels for the power made by cars on gas.

Ken.
 

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I'm glad someone started a thread like this! Who are the main porters for 2J heads anyway? So far I've seen the following:

- Headgames
- ODC Works
- CNCPort.com
- TheOldOne.com
- Twinz Turbo

I know Titan, RealStreet, IP, SP, etc all have their own head porters but I'm not sure who they're using.
 

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Super Moderator
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Discussion Starter #9
I'm glad someone started a thread like this! Who are the main porters for 2J heads anyway? So far I've seen the following:

- Headgames
- ODC Works
- CNCPort.com
- TheOldOne.com
- Twinz Turbo

I know Titan, RealStreet, IP, SP, etc all have their own head porters but I'm not sure who they're using.
On Twins Turbo, they offer a 'Golf Ball' surfacing option for the intake ports that adds $300 to the cost. The idea seems kick ass in theory... but how does it do in practice? Anyone get that port job yet?
 

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Super Moderator
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I'm glad someone started a thread like this! Who are the main porters for 2J heads anyway? So far I've seen the following:

- Headgames
- ODC Works
- CNCPort.com
- TheOldOne.com
- Twinz Turbo

I know Titan, RealStreet, IP, SP, etc all have their own head porters but I'm not sure who they're using.
[email protected] has done the work on my cars, as well as virtually every Supra built by SP Engineering back in the day. Evasive Motorports also is a frequent user of PortFlow's services.

There were, at one time, two top notch companies in Cali that did serious work on the 2JZ-GTE, but I cannot recall their names. Very old school OGs, like Bryce Danna, and a couple of other Texas heavy hitters, used those companies when Bryce's 887 whp dyno blast was at the top of Supra horsepower lists for longer than almost any other street car owner.

Ken.
 

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Premium Member
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229 Posts
Pocket port, stock valves, Kelford 202-D cams, Behives and be done with it..... I don't even think you need shimless at those rpm's (although some will argue that). K.I.S.S.
 

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OT here but I think that BC valvetrain will hold you back and cause float and those cams might hold you back from your 8400rpm.
I'm not gonna school you cause your an OG member but with the 3.4 you don't need to rev that high and if you want to your gonna need bigger than a 76mm to keep the power up there at 8400.
 

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On Twins Turbo, they offer a 'Golf Ball' surfacing option for the intake ports that adds $300 to the cost. The idea seems kick ass in theory... but how does it do in practice? Anyone get that port job yet?
A local high end machine shop called RavenWorks did some testing on intake port dimpling on a Dodge/Hemi motor. Their results were minimal power gains over a standard port job, but they did see noticable efficiency gains in fuel delivery. They were achieving the same AFR's with much less fuel. Keep in mind this was on a different engine and at the 350-400hp range, so take it however you want to take it. Interesting none-the-less.

They actually did dimple to a 2JZ head as well for an out of state customer. I got to see it while I was dynoing there and it sure looked cool. I don't know who the customer was unfortunately. Sadly RavenWorks closed it's doors close to a year ago. But if you ever wanted info straight from the guy who did the design, machining, and the testing I can give you his name and you can find him pretty easily on Facebook. Very smart and easy to talk to if you wanted to pick his brain on the subject.

http://www.ravenworksllc.com/page.cfm/newsletter.html
 

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I am as old-school as anyone, but I would replace those cams with a more modern design like GSC.

For my car, the S1's crushed the HKS 264's in every category - spool-up, mid-range torque, they just hit hard. My only complaint with them is the exhaust emissions (can't idle with window down), and the gas mileage (12-14 with an auto). The A/F reads perfect in the 14's, so it must be unburned fuel.

Al
 

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OP, if you roll with the T51R SPL BB, you won't have to rev to 8k+. That turbo peaks before hand (my normal JB did). PM me if you're interested in buying bnib one. I had a line on one earlier this year and can pass the contact info along to you.

I never did back to back testing but information shared on this board over the years it is pretty much definitive that over sized valves will not be beneficial to you with regards to your power goals.
 

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I wanna go fast!
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Not to say it's impossible but revving on a stroker is somewhat problematic because of the extreme rod angles. Not to say you can't do it, just an obstacle. Personally I don't like strokers at all for exactly that reason.

With regard to the dimple porting, what is the benefit on forced induction? I can totally see how the turbulence would make a difference on an NA engine but when you add forced induction to the equation I just don't see it. Then I would actually think it would have the opposite effect. Anyone with real knowledge on this who can set me straight?
 

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Toyota Hybrid Tech
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To op. when i built my motor i have in my car now, i thought about porting it but decided not to. i did go with +1mm valve and 272 cams stock compression. i hit 1077whp and mid 800tq. some other cars in my area laid less power with higher compression with totally reworked big dollar heads. in my opinion porting/polishing is over rated in some circumstances. it can hurt the flow if not done properly and cause less turbulence which will hurt fuel vaporization. unless its a total race motor that will see nothing but track use and trying to break records you can spend the money some were else like fully blueprinting the motor etc.

my 2 cents.

edit: forgot to mention my car is e85 stock comp and the other cars are e85 high comp.

nick
 

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hks is the best get the full kit
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Engine is an air pump.

1in pipe work with 3 bar pump, but it does not work for 10 bar pump because it will generate heat, also other issue and boom.
2jz head flow more than 1jz head and the difference between two engine is .5l. you are going for +.4l and do you think that the flow will be enough.
look for a well qualified porter and tell him to show and prove.

on other hand if you do a port job, you may lose torque in low rev range. Also if the port job is not perfect you may lose power and torque across all rev range as insanearmer have mentioned. Some people swear by 1.5jz because it produce more torque due to a smaller port= higher velocity. But the smaller port will generate heat for a higher capacity engine. The colder the air get in cylinder= more power.

Energy is conservative, by doing a port job you will gain something and you will lose something. So choose what you wanna gain and what you wanna lose.
 
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