TimO

The cartec turbo exhaust manifold is cast iron with a provision for a wastegate on the end near the firewall....I had one on my old mikuni blow through system. Not a good design!!! Donna we now have four orders for the South Florida Performance turbo header, TimZ, Joel, you and I!!!! If anyone is interested...the header should flow about 30% more than the stock 280zxt manifold and is guaranteed for three years against cracking. Talk to Abid at 305-233-8520. He will fabricate the header for either the T3 or T4 flange, and make provisions for a wastegate flange.

TimZ I ordered my cam on Friday from Elgin. Specs: Lift at the lobe .355 in take,.338 exhaust -with a rocker arm ratio of 1.47 that's .521 and .496 respectively. Duration (net) intake 240, exhaust 236 Lobe centers @ 114. I decided to go with the L/C of 114 rather than 112 for a flatter torque curve, and 236 duration on the exhaust rather than 226 because I want to take advantage of my higher red line (than Donna's). Should get it in a few weeks... I'll call ya. TimO

Donna (LS)......you've got mail! Still on the left! TimO

I'm deciding which new cam to buy and in the process I asked John of Elgin Cams the question regarding turbo cams having more aggressive duration and lift on the intake side. His answer was essentially the same as Timz...the biggest issue it to maintain flow volocity, to maintain a little more pressure on the exhaust side, that the torque curve is adjusted (flattened, moved up or down the rpm range, peak) by duration and degree of L/C. Overlap kills a turbo engine unless you want a peaky high rpm motor that can't be driven on the street.

Donna- Can't sleep huh! With all the cam specs and confusing opinions going through your head....gee I wonder why! As you know I run the larger exhaust valves. I don't know if they make a difference in my set up or not! I don't have a baseline for comparison. I would think with some of the Nissan builders and cam grinders such a Isky emphasizing the intake side on their cam specs for turbo z motors, maybe larger exhaust valves are not the way to go... only a guess. I would spend the extra money on porting your head, focusing on smoothing out the runner walls and concentrating on blending and smoothing the pockets around the valves. Or you could buy chocolate and send it to Sacramento!! On the left TimO

Jason- Hey Jason if you are considering the TWM's by all means do it. They are a pretty much hard core high horse power injection system but when set up properly they are very streetable, extremely responsive, and low maintenance once set up. There are enough of us running TWM's to give you a solid set of basline settings such as the acceleration calibrations. I don't know that TWM'make more hp in the mid range but properly matched to the right cam in a high flowing head, they can help make a lot of torque in the upper ranges. There are a lot of advantages of individual throttlye bodies. That is why BMW is able to make so much hp from their new M3, they are using individual throttle bodies. You will hear a lot of guys complain about the TWM's being difficult to tune and are too big to be responsive...I can tell you that I don't have those problems. I haven't put my 72z on a dyno yet but it's pretty quick, somewhere on the scale of mid to low 12's. If you want to talk specifics send me an e-mail and I'll send my phone number. Regards TimO

Sam- The Mikuni's I ran were 40's so they had immulsion tubes. Not sure of the hp I was getting at 8 psi but it was pretty fast, much faster than a Mustang 3.0 for comparison. If I were you I would not spend the time and money to convert the Mikuni's to EFI by modifying them to accept fuel injectors. I would sell the Mikuni motor and build a 280zx turbo motor. The amount of hp potential is far superior, drivability is much better, and by comparison the cost can be about the same as the blow through system depending on the engine management system you choose. I'll send you my phone number and lets talk. Regards Tim

Sam- I ran a Mikuni blow through system for 8 years. They are very tricky to dial in. I haved since converted to a TWM throttle bodie/TecII system. A Mikuni blow through system generally can not run more than 10-12 lbs although I was able to run at 14 because I sealed the carbs. If you run at that level you will need to constantly watch for failure of the float bowel seats. The trick with tuning the Mikunis is to find the right immulsion tube. Jetting depends on cam, head, exhaust, etc. You need to use a Malipressi (sp?) boost sensative fuel pressure regulator with fuel return before the carbs. You also need to run an ignition system that has a boost sensative retard like the MSD system. Lots to talk about. Send me an e-mail and I will give you my phone number. Good Luck TimO By the way watch our for that guy from La, Joel, he used to be from California!!!

OK Donna I'll wade in. For those of you who don't know me my engine is very similiar to Joel in La and TimZ(when he gets his TWM's). Donna's motor will soon join us. I normally don't join in on these posts but after reading the many and varied posts about camshafts, heated exchanges, and the mine is the best way comments, I'd like to say that I'm concerned that when posts are made, the newcommers check the advise on these posts with the professionals at turbo shops, cam builders, and the major Nissan speed shops such as Sun Belt and Rabello, etc before they take as gospel, the advise of those who appear to have limited experience and may be expermenting with their unproven set ups., as we all are as hobbiests. A number of comments and posts I've read lately are not based on sound science and correct physics. I think when we give advise, especially to the new guys (and gals..sorry Donna), that we make sure and let them know that our successes, and yes our failures, are just ours individual experiences and are not to be taken as an absolute. A simple example is camshafts....comparison of camshafts is a science that must be base on an established baseline of data which is virtually impossible to generate on a forum because many factors change from one engine to another especially when you consider different heads, porting, cam timing, etc. I think its great to learn what works for each of us,and whey you think it worked, but lets be careful especially for the new poeple, to let them know the perameters in which we have successes and failures with our motors. Hope I didn't affended anyone. TimO