240Z Turbo

The 3 fuel pumps probably run to it.

I have been working on a GT replacement for the stock rb26 turbos. What option would you prefer if you could swap in some gt cartridges? GT 28RS Disco potato GT 2871R

Yea Mike, don't be a dipstick! Sorry, I couldn't resist the opportunity:)

Not a problem to rebuild. Another option is the new bb cartridge from Garrett and it allows us to use the standard, non GT, wheels. Also, if the compressor wheel is damaged it may also be a good time to upgrade. Several options to choose from.

Thagard has 1 "g" I see you made a slight mod to the front of the pan. Did your mounts move the engine too far forward or was this used in a different car? The pan design was mocked using Wong's cnc mounts. It looks like without the mod it would have been close. I am glad to see it has worked out for you. BTW, I sent you an e-mail the other day. Also, I would like to discuss a GT replacement for the stock turbochargers with you. It will save a lot of money over the HKS route. Nice work!

When I get a chance to sit down I will post the theory as it has been explained to me. It has been shown and proven to provide gains. Pic below is of early 80's Chevy steel head chamber. Similar chamber design, same concept. By no means am I knocking your work. I always complain and emphasis the lack of attention that is paid to the combustion chamber. While I am not an expert, I am smart enough to pay someone with the knowledge to make the appropriate modifications. I think that attention to detail puts you in the 5% of folks that do it right. Keep up the good work. BTW, that attention to detail is why so many Jap L28's are making big power and so very few US L28's are doing so. It is conceivable that gains in the 15%-20% can be realized from the combustion chamber side of the head.

This one is new, but perhaps you are correct.

If the head is worth more than the car I don't think you will get much business. BTW, from the looks of the paint job in the engine compartment, I would choose the car! It should be noted that this topic has been covered and detailed pics of similar combustion chamber mods have been shown. While most don't touch the combustion chamber, which is key to flow and combustion efficiency, I doubt showing a pic of your work will make much difference. There are additional pics that have been posted besides the one below. Nice work none the less. With all that work I would have thought you would angle the spark plug towards the exhaust valve. Just another trick I have seen pictures of.

JUST FYI on a good deal http://www.ka-t.org/forums/viewtopic.php?t=9050&sid=b0274df896adf2b27ad2680e47d590e3

working on Garrett GT upgrade for stock turbo's. Will use stock turbine/comporessor housing that have been machined for upgrade.

Tim, Contact http://www.spdexhaust.com http://www.burnsstainless.com Ask them a price for a slip joint or double slip joint. I want to say they were in the $20 range for both pieces. On the corvette I just used a single slip and it had no issues. BTW, each header used a slip between cylinders 1-2 and cylinders 2-3.

Nice turbo buddy, looks like the one I have. You can constrain while allowing for movement. Make sense? Use the heim joints to isolate vibration and provide additional support. The joints allow for expansion in certain directions. I braced to the flange and to the bottom of the block. It really added a lot of rigidity to the setup. I would just reweld the header and move on. Expansion bellows are not the only option. Slip joints are very cheap and provide the same expansion relief you seek. I used this same concept on the twinturbo ZR1 header. Pics below. Whoops, will dig up uncensored pic and send via e-mail.

Endyne has said my head is finished, but I have yet to see the actual flow sheets. However, upon a visit I did get to see several port configuration tested on my spare head. Final flow numbers on the intake ports are said to be 311cfm, which is about 5cfm greater than the full race 2JZ head, but ~80cfm less than the Honda 4banger heads developed in their shop. Head specs as follows: HKS 280 10.25 cams Fidanza cam gears Ferrea springs/retainers/seat locators 1mm oversized inconel exhaust valves 1mm oversized SS intake valves Endyne Port Job Endyne combustion chamber mods I will post official flow sheets and pics when they are received.

I have to change my opinion now that I have 2 Tial BOV's for my new project. Therefore, if you are not running 2 BOV's then you are doing something wrong. I am sorry Joel, your turbos are now going to explode.

You know what they say...if you go to the junk yard you get junk.

I would probably opt not to use the same 16G turbo's that I used. Was a bit laggy for the average guy. I don't know what you can expect for $300/turbo as you get what you pay for. I can sell you new Garrett units sized for your pleasure.

Here is an initial dyno graph from the twinturbo setup before the fuel was leaned out. This was 28psi and no nitrous. Car was running balls rich, but pulled well to 7K RPM even though it was only street tuned. I later leaned out the fuel based on the dyno graph, but never had the opportunity to dyno the car again. With the AFR set correctly the power should continue to climb to redline. 28psi and no nitrous felt much faster than 17psi and the 125shot which netted me consistent 133-134mph in the 1/4. Based on calculations this said the car was putting down ~490hp@wheels, which would be consistent with tuning changes. I thought the car would probably make ~480-490hp@wheels without nitrous. This was also pusing through an automatic.

remove all the spark plugs so you are not working against the cylinder pressure. Place your finger over the #1 spark plug hole. Have someone turn the motor with socket wrench. On the exhaust stroke as the piston comes up you will not feel any pressure, but on the compression stroke as the piston comes up it will be pushing air past your finger. As far as finding precisely TDC, it doesn't make much difference if you are just changing the head gasket. Just mark the chain and cam gear.

:)Not with fabrication:)

The first place to start is the spark plug holes. Use the dremel to remove all of the thread within the spark plug holes and then work your way to the valve guides with the valves removed. Once this is done use the attachment to write your name onto the deck surface. The Dremel is a powerful tool for working on a cylinder head.

Remember, pressure is created by the resistance to flow. Answer to your question, you are limited to what you can shove in front of the early z so I don't think you will find something that is too big. It may be overkill, but not too big. The downside is the ability to flow air to the radiator to keep the car cool. I have put several large coolers on Z cars and here are some pics. 28"x8"x3" 20"x7"x5.5" 24"x12"x4.5"(Joel's Car)

4 is correct. The silver striped is the ACR as you can tell by the rims. Dynoed at the 550hp@wheels range. The red viper is twin turbocharged and made 900+hp/1100+ft-lbs@wheels. Currently building a 500+CI motor for it with better heads and cams. I will be retuning that car some time in the near future using the AEM. I did some tuning on another twin turbo Viper using the AEM some months back to see if we could tweak some more power from it. We actually hit 170mph in that car and it was still pulling. I hate to say it, but I tapped out. I had visions of my being killed and missing my children. Although it is not visible, there is also a Lingenfelter stage 2.5 TT vette making ~650hp.

That looks very nice. Just out of curiosity how will the TB's we situated?

air flows better through round tubing instead of rectangular. However, we did increase cross sectional area with this piping. Pressure is affected by turns within the piping, but it is most likely neglible. Calculations smalculations, there just isn't any room!