Pyro

Slow down your towing speed would help. A 383 with a set of vortex heads would make tons of low rpm power. You need small intake ports and a long stroke to make low rpm torque. A short rod, 400 sbc would be even better for low rpm torque. Then a short duration high lift hy-roller cam would be worth 20 more ftlb over a regular hy-cam.

But why do it when 500 hp and 500 ft lb small blocks are very easy to build now-a-days. Then add a 300 shot of N20 and push the hp to 800 hp which is more hp than you could ever use in a Z. Big block are slow revers, very heavy, very wide, suck unbelievable amounts of fuel, and are better suited for heavier cars. I know because I have one of those pigs in my truck. What we really need is more LS1 installations! Forget that stoneaged BBC unless it is in a 4000 lb car with a huge gas tank.

From what I have read, 3 to 4 psi of back pressure is considered a very low restriction exhaust system for a NA engine. I don't think 0.5 psi is obtainable with a full exhaust system. Maybe 0.5 psi is obtainable if only run a very short and straight pipe from the turbo turbine is used as the exhaust. 5 psi is pretty good but I would think the lower the back pressure, the louder the exhaust.

Clifford.

That is right. 1st gear in a 700r is very low so there is a big gap between 1st and 2nd gear. I read that it was designed to get a big heavy car moving with a 3.08 diff gear and a weak engine. 200's have about the same gear ratios as a TH350 (only for the first three gears of course). I think 200's have a 2.50:1 first gear and a 700 has 3.08:1 first gear. I personally hate 700r's and would never own one again. After chewing up a few "high performance" transmissions from GER then breaking a neck off a torque converter, I switched to a GM T5 5spd and have been very happy ever since. Make sure a local trans shop does the rebuild and get a warranty! Don't mail order a trans like I did unless you like paying a lot of shipping costs and like having a lot of down time!!!

A little overkill but who cares! right? I have heard of people running 17 psi with the stock turbo without any problems and pretty good perfromance. It is not so much the amount of boost but the amount of flow that will limit the stock T3. So, try shifting no later than 5000 rpm. A friend of mine has that exact set-up and runs 14 to 15 psi of boost and his car runs strong.

If I had to do it all over again I would get one of these. http://www.jspecautosports.com/catalog_product.aspx?prod_id=37 Much cheaper. Add it all up and see what I mean.

A stock T3 turbine is not a good flow match for a T4 compressor. So you should make some more hp due to less restriction on the exhaust side. However, expect more lag, maybe 500 or 600 rpms more. I think the new turbo has the "ability" make another 100 hp, but I don't think you will get another 100 hp unless more rpms and more boost is made. A simple turbo swap will not yeild that much power. You will also need a spacer to use the bigger turbo. I think you should had modified up your old turbine and stayed with the t4 H compressor wheel. IMHO

Beware of longer spool time. If the max shift point remains the same then the usable power band will be reduced. Most Z's will only make power to 5000 or 5500 rpms with the stock cam. If max boost is moved from 2800 rpm to 3500 then power band is greatly reduced. Therefore, a bigger cam with proper valve springs would be a good addition for the bigger turbo. A bigger turbo alone will hurt the perfromance of a daily driver especially on a automatic tranmisson car. Why do you feel you need to upgrade your turbo? Have you tried turning up the boost yet???

A small block will fit with no problem no matter what the internal dimensions of the engine are. A 396 cid sb can be made using a 400 crank that has been offset ground to hold small journal 327 rods. This gives another 0.070 stroke to the 3.760 stroke of the 400 for a total of 3.830. Then bore the block 0.060 over and there is the 396.5 cid sbc. The same thing can be done to a 350 crank for a 367.5 cid engine.

My 71 240 with 350cid and N20 has run 10.7 at 135mph (6.9 at 110mph 1/8 mile) with drag slicks but stock R200 diffs and axles don't last more than 10 passes. It not fun when parts keep breaking. I feel low 12's/high 11's are about it for the stock Z rear end components if durability is an issue.

Even if all alcohol was illegal and the penalty for DUI was a death sentence. There would still be the same 2% of the population drinking to excess and driving. The "low tolerance" laws are aimed at stopping the small percentage of people who can't stop from drinking themselves blind and crashing into innocent people. It is a shame that a few bad apples are giving the rest of us "slightly drunk" drivers a bad name. But that is why most laws are made, to get those few bad apples.

Common problem but not a big deal. Just install new threads (heli-coil). Buy some at NAPA or have a machine shop do it.

Yes Michael, I have always thought the small frontal area of the 240 had a big part in reducing the total drag. Eventhrough the CD was bad, the small frontal surface reduced the load.

Used the hooker header version model 2100. They fit nicely and have 3/8" thick flanages. This is the model recommended by JRT V8 conversion manual. I would also get them coated becuase they rust and look ugly very quickly.

Make sure the distributor is advancing correctly. And make sure the vacuum advance is connected and working! My Z gets terrible mileage without the vacuum advance connected. Did you change oil weights? Thick oil can reduce mileage by a 1 or 2 mpg's.

It is all about sound pulses. The duals sound like two big 4 cylinder engines running side by side. A choppy sound, especially with a big cam. With single exhaust (yes, 2 pipes into 1), the sound pulses cancel each other out inside the pipe and it makes a deep mellow sound. Plus it greatly reduces resonance. Yes, sounds are hard to describe. But my V8 Z sounds like a loud Ford Mustang now. The single exhaust V8 sounds like a very very mean import engine. In fact, my car with the single exhaust recieved glowing complements from a local nascar engine builder after a few 7000 rpm drive by's. Now people just look for a Mustang when I drive by. IMHO, the V8 already removes a lot of the Z import flavor. And the Ford V8 sounding exhaust totally kills the Z import experience and makes me think I just should buy a muscle car and sell the Z. I'm running a similar set up as you are. 425 hp plus 175 hp N20 and my car is running 10.7's at 135 mph using a T5 and a R200 3.90 diff.

I bent over backwards tring to install "true duals" in my Z. In my first dual job, I cut out 5 gallon worth of stock fuel tank (on the passenger side) and relocated the filler to make room for a muffler. That worked very well but the tank was only 11 gallons. Then after a few years of that, I cut everything out and installed a 10 gallon fuel cell up in the car (about 1/2 way) and build a new floor board to cover the cell. That gave a lot of room for mufflers and fuel pumps. However, I found out quickly that I didn't like the sound of duals on a Z. It sounds like any other V8 car and doesn't match the Z style. I miss my single exhaust with the V8! If I had to do all over again, I would just run a nice mandrel bent 3" single pipe out the back and a very smooth 2.5" Y-pipe before that. I was running mid 12's with a single 2.5" exhaust without any problems.

Put in a cam with 245 degrees of duration at 0.050 and 3800 rpms will not seem so high.

I guess it all depends how many lawyers you have in your state. hahah However, I think the chances would be pretty low to have an insurance agent look under your hood after a fender bender. Get the minimum insurance and drive carefull. I guess if you crash bad enough to throw the engine out on the street it could case problems. Face it. You are 17. It will be very hard and very expensive to get insurance if you tell them everything. Those insurance companies think a stock Z is fast! HAHAHAH. I guess they didn't see Full Throttle with the two 240s. You know, the fastest Z made. hahaha. So, you are already in a high risk catagory with just a stock Z. But in the end, it is up to you. Well, I need to go. I have some guns that I need to bury out in the back yard just in case G-men try to take me in.

I just give them the VID numbers and act stupid. Remember, it is always better to ask for forgiveness than for permission. 17 years old is going to be expensive. Maybe you should buy an old 4 door maxima with a V8 conversion.

Sure it is possible. But it depends on your bank account, free time, mechanic and fabrication skills, garage space and tools, complexity of the engine and drivetrain, and your knowledge of engine swaps. A simple, old school, 350 swap with auto transmisson following the JTR conversion manual is the easiest and cheapest to do. Especially if you order an install kit that comes with the mounts, crossmember, and drive shaft. LS1's swaps can get complicated because of EFI and ECU. Do the math. It is most likely cheaper to buy one already done and sell your car.

I'm using the stock T5 slave clyinder with a 7/8" wilwood master clyinder. I have used this setup for almost ten years without any problems. I'm using a heavy clutch so I had to run a support bracket from the firewall to the inner fender to reduce firewall flex. FYI, I had to cut the lower lip off my lakewood bell housing to gain ground and exhaust clearance.

Have you even see one of those nossels that attaches to a water hose that will suck a soap solution out of a can? When the main flow suddenly hits an area where the volume quickely gets bigger, it creats a slight suction at the edges of the flow, even if the flow is under pressure. Exhaust existing the combustion chamber will also help suck in the intake charge (scavaging). However, it doesn't happen all the time. Just at certain rpms.

I saw the show and it made the 240z look bad. They added parts that made the cars slower! Big cams with no gears and no compression is a big drag strip NO NO. If they were on a budget, they could have recieved free advice from this forum and gotten much cheaper parts from pick-n-pull that would actually do something. They should have installed an early style 5 speed, R200's with 3.90 gears, and L28 short block with flat tops. And leave the SU's on please!