jgkurz

I decided on a .82. I am hoping the better designed housing, plumbing, turbo, and exhaust minimize the additional turbo lag...

My dyno chart with the .63 drops off into the abyss after 6000 RPMs. I was never sure what the reason was.

Interesting. I would have thought it would have been the other way around with the .63 being better for daily street driving.

Thanks for the response! I'm hesitant to go to the .82 for the same reason you mentioned. I don't want that.....wait for it..... experience. The new turbo is a GTX3576R so far more efficient than old turbo. This plus having more displacement might spool acceptably with a .82 also with the benefit of more peak HP. It's a tough decision..

Hi All, It's been a while since I've posted. I am going to get my Z back on the road but before I do I am going to upgrade the turbo. I currently run a .63 T3 turbine housing on my 3.0L L6 that got me to 455rwhp and 462rwtq. This was likely with a fair amount of back pressure but with decent spool. I prefer some boost before 3000 rpm. I'd really like some feedback from those of you running a .82 A/R turbine housing. Thank you! -John

How'd this turn out? I also have a 77z and will follow your lead if all is well. -John

Thanks DK but I found a valve cover for sale locally. I appreciate the reply.

Thanks for the reply but I'm looking for a valve cover that is cleaned up and ready for install.

I'm looking for a polished L6 turbo valve cover. Must be the 81-83 L28ET type and be a mirror finish. Does anyone know where I can buy one or who can perform this service?

Just curious, why wouldn't you want 16"? I am able to get 245-45-16 on HRE 505's under my stock rear fenders. 17's would work but tire size would be much smaller. Finding used 505's will be difficult. HRE will make them new for you but you'll be close to 1500.00/wheel to have them built. I know because I called a while back.

I saw this in my local mall today for $234.00. Pretty cool looking but I but decided to pass. Might be fun gift for a son or daughter who has a parent with a Z. 240Z RC Car

Cannonball89, you are a man after my own heart. Here's my setup. I can't say enough good things about how much of an improvement I got from going to the divorced wastegate setup vs the internal gate. Here's a bit more info on my car. http://www.fstrnu.net/ Everything is pretty much the same except I'm in the middle of swapping in a GT35R.

Thanks guys. My Dad worked for Ford for 40yrs in Michigan and just retired so he has never been too excited about my affinity for the Datsun Z. I might compromise and put a boosted stoker 351W in my Z someday and start making some serious HP.

Video from the rear http://www.youtube.com/watch?v=DtLzP0GgzMs

I flew to Michigan to spend some time with family last week and to attend Ford Fest 2011 at Milan Dragstrip. The day of the event on Saturday was a bust due to weather but Sunday was great and near sea level altitude density. My dad ran a personal best of 9.18 at 146mph on all engine. Not bad for a car without wheel tubs on 10.5" slicks and full interior. The engine is an aluminum 427 side-oiler stroked to 502ci with a single Holley Dominator 4barrel. On a 9.20 dial he ran a 9.22 and lost to a guy that ran exactly his dial-in. Oh well. Still had a ton of fun. Enjoy the video. http://www.youtube.com/watch?v=WNsTaoyIzyc

I just saw the movie "Senna" then came home and watch the Top Gear tribute. It was moving to say the least. In addition to his obvious skill, I was struck by Senna's humility and desire for perfection. I also learned that Patrick Head, technical director for Williams racing, was officially blamed by the Italian courts for Aryton Senna's death 13 yrs after the accident. He was never charged due to the statute of limitations. Apparently the steering failure was caused by "badly designed and badly executed modifications". Unless there is outright negligence, I find it odd that a F1 senior engineer could be blamed at all let alone 13yrs later. The politics of F1 are significant to say the least. Another interesting note, according to the movie there have been no deaths in F1 since the changes implemented after Senna's death. Maybe God had a purpose for this gifted driver. I'd like to think Aryton Senna would have seen it that way.

I first learned about compound charging when this car came onto the hot rod scene.

That's how I expected it to spin. My GT35R is relatively dry of oil which may have an effect. I wonder if oil pressure would make a difference?

Ugggg. Oh well. I guess I'll wait to see what the expert says. On another note, I took apart my current turbo and measured both inducers and exducers. Looks like I have a 50 trim compressor and a T350 stage V 10-blade turbine wheel. I use a heavily modified version of the Nissan .63 turbine housing that has been machined to fit the T350 wheel. On the dyno I made 455rwhp. That equates to 536 crank HP if 15% driveline loss is calculated. This matches my 1/4 miles times as well so it seems accurate. I am surprised the 50 trim compressor made the power it did. Cool. Since I need to use my Nissan turbine housing so I don't have to re-invent my DP and external wastegate setup I am going to have the GT35R turbine wheel changed to a T350 wheel. My research suggests the T350 wheel may actually work better than the GT35R turbine wheel. Regardless, they are nearly identical in specs.

Thanks guys.The journal turbo is broke in with probably 10K miles. Now the part I left out. The ball bearing setup is used, not a lot of miles but used nonetheless. It was a friends who upgraded to the new GTX35R. I would think that would be broke in enough to spin more freely than my journal setup. I'll probably have it checked out professionally to be sure.

HI Everyone, I just purchased a Garrett GT35R ball bearing turbo for my L28ET setup. My current turbo is a T3/4 hybrid that has surpassed my expectations but I knew could never be as efficient as a modern ball bearing turbo. The GT35R is visually larger than the T3/4 which was expected but one thing I was surprised about was how freely the wheel spins. For some odd reason I thought the ball bearing turbo would spin more freely than the journal bearing in my T3/4. It does not. The GT35R spins with about the same resistance as the T3/4. I'm confident my GT35R is a the real deal (not a knock off) but I was surprised is did not really spin more freely. For those of you with ball bearing setups, is this normal? I'm wondering if I should send it in to be checked out. -John

That's some serious detonation... Did you go to a Cometic gasket. I hear they are excellent. As a side note, I use a Nissan head gasket with an O ringed block. So far no issues with boost up to 26psi. knock knock knock

Excellent write-up Paul. I learned some stuff and validated info I thought I knew. I have experienced the above engine characteristics first hand with my turbo L28 and and early N42 intake. Peak torque is exceptional since the ports are so small but big HP (500HP+) requires extreme boost or a BIG turbo as compared to a better breathing engine. A more free flowing intake and head would easily make more power with my same turbo. Unfortunately I think I'd have to sacrifice peak torque due to the velocity reduction caused by bigger ports. A benefit would be a flatter torque curve which would make power delivery a dream compared to what I deal with today. Wait for it......wait for it......BAM!!!! On the other hand, making peak power at 6K or below (due to small ports) is MUCH easier on the L28 with it's long crank vs. folks who spin 7K and above. I've never broke a crank or damper yet.

Thanks JT! I run Mobil1 10w30 for everyday use and Mobil15w50 for track days. Guess I better add a zinc additive so my cam stays in good shape...

Jt, what zinc level would be normal to avoid premature wear?