madmatt48

Goodafternoon fellow Z fans, I recently picked up a showroom looking 1986 300zx turbo Z31 VG30ET equiped Z. The previous owner thought the head gaskets were bad because he saw smoke coming from the exhaust pipes. I first checked the spark plugs to find mismatched spark plugs all severely fouled. Two plugs were Bosch, two were NGK and the last two were Autolites. I changed the spark plugs to new NGK heatrange 6 and it fired up however would not hold an idle, the only way it would run is my pushing the accelerator pedal and holding 2 to 3 thousand rpms to keep it running. During this time I saw a lot of black soot fluid coming out of the exhaust pipe. I found this to be gasoline and it was dumping out of the exhaust at a very disturbing rate. I suspect injectors are possibly stuck open however do not know of a home test to determine this cause for sure. Also would like to hear other experiences of this nature and what probable causes could lead to this strange fuel out of the exhaust problem. Thank you again, Matt

Hi David, I was looking around ebay today and happened to see a Ford V-8 mount set up for the 240, 260 and 280z bodystyle. see this link: http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=250730638517&viewitem=&sspagename=STRK%3AMEWAX%3AIT if the reserve price is not set too high, that could be a good deal to help your installation.

I retired from the Navy 2 years ago. Here are some pictures of the new project 240z.

Purchased my new project 1972 240z, no idea the last time it had actually started or had driven before. The last owner before me had not started, driven or even registered it for years, how many truly unknown. I am the second owner of this car, I still have yet to go to the DMV and change the original 1972 title to my name. This z still has the original 1972 dealer options paper in the original dealer folder. A gem in the rough all original except for the wheels and tires(good and bad thing). This is the first 240z I have seen with the original bright orange paint under the carpet on the floor boards and in the spare tire compartment unbelieveable potential in this restoration. The car's topcoat paint is a mixed primer and lots of wet sanding has been done so its pretty much cosmetics and a paint job and this all original 240z will be an auction block hero. Ok now for the problems: Put fresh gasoline in the tank, used an electric fuel pump to purge out all the bad gas into a gas can until it ran with fresh gas, reconnected it to the mechanical fuel pump and successfully the engine started. Warmed and ran the engine for around 30 minutes until it reached a nice steady 800 rpm idle, I then figured why not take it for a spin around my property..... Well that ended up being a mistake.... I put the car in reverse, drove backwards successfully, touched the brake, put it into first gear and the rear wheels would not move, they are locked and the brake pedal went to the floor and stayed there. There was still plenty of brake fluid in the master cylinder. I believe the brake drum cylinders actuated once and locked into position probably due to the many years it sat and did not drive or apply brakes. Any ideas on how to remove the stuck brake drums without totally damaging the rest of the connecting components? How many of you have experienced this great stroke of luck? Cheers, Matt

Several years ago, I used a Mallory unilite distributer that fits L-24 through L-28 nissan engines not recommended for the fuel injected engines. They also make dual point distributers for the early 240z through the 260z prior to going to electronic distributers in the 1975 models. There is no need to use a mallory unilite if you currently have an electronic distributer, I see you have the 1978 model so that distributer should be fine as it is. If you still would like an aftermarket, see this link for the unilite: http://malloryperformance.com/ProductDetails.aspx?modelNumber=4563901&productID=2269&majID=530&minID=0&selection=2&minselection=23

The rotary thread came to pass when it was pondered installing rotary engine into an early S30 Z body with supercharger, turbocharger, wicked 4-barrel carburator, whether blow through or draw through. Ideas begging to be explored. The engines are light with high rpm and power potential just waiting to be hybrid in a z body. Two rotor, three rotor or four rotor they're powerplants that scream in their own unique tone and challenge all that tune it to find ways to keep it all on the ground and in track.

Thanks for the Racing Beat link. I like that holley / supercharger rotary set up in your picture, how close are you to shreading tires and dragstrips with it? A rotary supercharger set up with 14,000 + rpm potential.... Just makes me think about a large ball bearing T4 blowing through the carburator into that supercharger. Then I would have to consider the maximum boost a rotary could handle and still keep its apex seals, rotors and housings intact...What kind of side or bridge porting would have to be done to the rotary for that type of extreme boost... Supercharger boost is right off the line and stabilizes around 5,000 or so rpm, most large T4 turbines take around 5,000/6,000 rpm to reach their peak and the rotary engine can spin up to 14,000 rpm. Thats around 9,000 rpms of T4 max boost potential to play with in each gear before reaching redline. The supercharger has the boost off the line strong until around 5,000 rpm when the T4 takes over...Traction for that kind of power would have to come from some serious soft compound slicks. I wonder if that idea has been tried yet? If not, well that's the next one I will attempt when I source a cheap S30-Z, a used 13BT and a bunch of other parts.... One of the reasons I like blow through is that I do not need computers or complicated programs to change fuel settings. Just another set of jets, adjust the regulator monitor boost, egt and afr and try again. There is a Ford GT that has a mid engine supercharged V-8 that was modified by Hennessey with additional twin turbo kit feeding the supercharger and was quite powerful. http://www.hennesseyperformance.com/ItemDetail.php?Item_ID=230&cart=lAIBNXfK&DoThis=Ford+GT&ActionReq=Where The redlines for most V-8 engines are not even close to that of rotaries. What are your thoughts?

Very impressive, thanks for all your advice since we started these posts. I have been thinking of trying a rotary in an early Z body for quite some time. The ungodly rpm potential, the light weight of the rotary engine and unbelievable power they can put out with large turbochargers. There was this guy in Japan I used to race against in Yokohama in 1999. He had red FC3 with a highly modified 13b with a HKS T51 SPL BB turbine in it and his car was a monster I would get him some races and he would get me sometimes if I made a shift error of any kind. I had a T51 SPL big single turbine in my R32 GTR at the time. Its amazing how much the 1300 cc 13b rotary can do with such a small displacement and six compression strokes per engine revolution. Now the only thing I am wondering is where to find a 4 barrel intake manifold for a 13b engine that would fit american Holly, Demon or Edelbrock carburators on it for blow through applications? I have seen several successful weber down draft combos for 12A and 13B however, have not seen american carbs on the 13B yet.

I always did like 20b 3 rotor engines, 4 rotors, that would be great. How do you attach the eccentric shafts or do you fabricate a specific 4-rotor from billet?

I didn't specifically mention using the actual pictured diesel turbines in a gas engine however you could if your engine was built to handle that level of boost. Of course that set up would require specific fabrication to place the turbines and pipes not to interfere with the steering shaft of left hand drive Z cars. Give a logical reason why a sequential turbo set up like I stated wouldn't work? Provided you select the proper twin turbine size appropriate for the level of mods in your particular car. In addition to that, you could essentially mount a turbocharger anywhere you like so you could essentially have a triple or quad turbo car if you so desire and have the engine compression and quality of fuel to run that set up. Think outside the box my friend before you insult people's ideas....

You could also go the route that many diesel tuners go for twin turbo. You can use a single turbine exhaust manifold or header and hook up one GT25 then have a T3 flange connected to the downpipe of the first GT25 and hook up the second GT25 T3 flange. You also run the compressor discharge from 1st turbine to the intake of the second turbine so you only have to run one large air cleaner. They run in a series but still getting the boost and horsepower gains of twin turbo without finding a special twin turbo header or manifold. A popular B&D set up for many diesel trucks. The one in the picture is for the cummins straight-six turbo diesel engine like the one in the Dodge Ram 2500.

Now that is a nice clean solid blow through set up. I used a centerforce II clutch on my prior 1970 240z with triple weber 45 setup and worked great not too much grip to where you blow transmissions when running sticky tires but enough to hold around 300hp reliably. What EFI fuel pump are you running for your reliable set up?

Thank you for your replies. I had not planned on installing a tap on the carb hat or the larger return line, now that you mention it, I like the ideas. I will stop experimenting for now, get the EFI fuel pump and the other growing list of goodies you both mentioned and not fire it up again until I have it all installed. After all, the race track I go to is closed until next spring so what's the rush? Getting the Z running again after so much time sitting in the garage had me on a rampage to drive. Well I will exercise more patience (hard to do) get all the noted mods and hopefully have it ready to roll by next April/May when Top Gun raceway opens again. By the way, do you have a better description of the distributer plate modification that you and Tony were talking about and the best way to route the carb hat tap?

Yes, the state of California is real sad when it comes to mods. Following their rules would result in what you stated above maybe a few seconds better than stock. My question is open to any legal licensed S-130 280zx in any State in the U.S. Would like to see or hear about the best 0-1/4 mile times that have ever been achieved thus far using an L-series engine.

Do any of you by chance know the fastest 0-1/4 mile drag time achieved by a 280zx/ S130 powered by an L28 series engine that can still legally wear license plates?

Have an A/F ratio gage with sensor mounted on the downpipe, Exhaust Gas temp gage with thermocouple sensor tapped just after the turbine flange where 6 meet one and boost gage that reads up to 30psi. I agree with you, a very good investment.

I have pictures in my 5 October posting. As for some video footage, I'll work it this weekend once the new higher fuel pump is installed and carb adjustments are made.

The Demon is specifically designed for blow through turbo and supercharger application. I could understand if I had a regular Holley, Carter or other make of carburator that was not intended for blow through application but this carburator is. The Demon installation instructions do not state your above comments that you must select pressure of fuel to be above that of the boost. That is why I picked this specific carburator and use a boost rising fuel pressure regulator. I receive my new fuel pump tomorrow morning and I will run this 155 gph pump with the current 72gph in tandum and that will be 227 gallons per hour of fuel potential running through the Demon 650 cfm carburator. That is a lot of fuel pump capacity with the pressure being just over 9psi. When I had the fuel starvation or pushing problem last weekend, the boost was set way down to only 6 psi. If your above description is correct, I should not have had that problem being my fuel pressure was 9 psi which is 3psi higher than my boost. Thank you for your updated information and ideas. I will know this weekend where I stand with fuel pressure whether or not I will need to order the super hoss of an EFI pump. I would like to see the distributer plate modification Tony-D was talking about which would be a good thing to have to avoid advancement under boost. Every safeguard to prevent blowing an engine is a good thing. Thanks for all the great ideas, hopefully I will have a monster runner yet.

Thanks for the advice, I was very fortunate that the lean condition from the vapor lock didn't take my engine out. I can attest some of that to the cold 9 heat range ngk iridium spark plugs and 110 octane race gas. I currently have a bosch boost sensing fpr however, it cannot do its job without a pump that puts out enough pressure for it to regulate at boost. I had originally run the factory efi pump dialed down with the regulator however, it gave out during my first start attempt a few weeks ago. If the fuel pump I have already ordered does not supply enough fuel pressure, an efi pump will the next pump ordered and installed. It can always be dialed down with the regulator and the excess sent back to the return line.

Well finally started the Demon blow through set up, did some adjustments to the floats, primary/secondary idle screws and air fuel mixture screws, holds an idle well. Did about 10 power test launches in the drive way in first gear and the rear tires that would get a slight chirp with the past fuel injection set up went up in smoke until I ran out of driveway. Figured after that, well its road test time. Got out on one of my county roads and gave it a mild launch at 1500 rpm then slammed the pedal to wide open throttle. Shifted to second gear at 7000 rpm and then the engine surged, suspected vapor lock. Stopped car, looked at the float windows and as I suspected from the engine reaction they were empty, no fuel. Back to the garage again adjusted the fuel pressure regulator to the maximum pressure setting, tried the same drive again and vapor lock a second after shifting to second gear at W.O.T. Back to the garage again, laid a bunch more burn outs in first gear to cover the driveway with multiple black streaks to celebrate that its alive after several months of planning. I ordered a much larger carburator fuel pump that will deliver what this demon needs to feed the Frankenstein. The bad news, didn't get it tuned in time for the last Top Gun drag race of the year. The good news is it runs real strong until it runs out of fuel. Another test drive following the installation of a very high volume fuel pump will be next. I love the smell of 110 octane in the morning... The intake sound the Demon makes combined with the sound of the exhaust straight from the turbo downpipe demands respect.... Looking forward to the first Top Gun drag race of next year.

Well finally started the Demon blow through set up, did some adjustments to the floats, primary/secondary idle screws and air fuel mixture screws, holds an idle well. Did about 10 power test launches in the drive way in first gear and the rear tires that would get a slight chirp with the past fuel injection set up went up in smoke until I ran out of driveway. Figured after that, well its road test time. Got out on one of my county roads and gave it a mild launch at 1500 rpm then slammed the pedal to wide open throttle. Shifted to second gear at 7000 rpm and then the engine surged, suspected vapor lock. Stopped car, looked at the float windows and as I suspected from the engine reaction they were empty, no fuel. Back to the garage again adjusted the fuel pressure regulator to the maximum pressure setting, tried the same drive again and vapor lock a second after shifting to second gear at W.O.T. Back to the garage again, laid a bunch more burn outs in first gear to cover the driveway with multiple black streaks to celebrate that its alive after several months of planning. I ordered a much larger carburator fuel pump that will deliver what this demon needs to feed the Frankenstein. The bad news, didn't get it tuned in time for the last Top Gun drag race of the year. The good news is it runs real strong until it runs out of fuel. Another test drive to follow installation of the higher volume fuel pump.

Ended up getting a new blow through carb hat single 4 inch entry instead of the two smaller entries since I am just doing turbo for now and I can always hook up the two entry carb hat if I decide to add a supercharger to the mix later. For now, I hooked up the EGT, A/F sensors, downpipe, all the intake and exhaust bolts, boost lines, hoses and blow off valve. Need to fabricate the throttle linkage to where it will actuate the carburator throttle on the side since its different from where the fuel injection throttle lever is on the front. May either use a Mr. Gasket throttle cable kit or make a large throttle lever that will reach the carburator from the stock linkage if it does actuate the carburator throttle to wide open throttle from the shorter throw of the stock linkage. Also will have to cut the hood to clear the large carb, its spacer and the very large carb hat which will stick out of the hood and give it that shaker hood moving kind of action when revving the engine. Then put all the accessories and cooling system back on the engine and get ready for a test fire with 110 octane vx race gas. Well have to wait until another weekend opportunity to progress further on this project.

From your description of the problem, it sounds to me that your internal wastegate could be stuck in the closed position which causes the turbine to put out its maximum pressure and spin to its maximum rpm limited to how much exhaust pressure is driving it. Normally the limit to the internal wastegate for boost pressure depends on the spring inside it, once the boost is high enough it compresses the spring inside the internal wastegate actuator and the arm actuates opening the turbine exhaust bypass valve releasing excess exhaust that is not needed to maintain the amount of boost that the spring inside the internal wastegate is rated at. One way to isolate the cause of the stuck internal wastegate is to disconnect the internal wastegate rod from the wastegate actuator and move the back and forth to verify the wastegate arm opens and closes the wastegate valve freely. If it is stuck and does not move back and forth (open and closed) It could be either stuck or seized due to something lodged in there, excessive rust or heat stress corrosion from sitting a long time (the valve is iron and so is the turbine housing so it could rust together) If that is the case and it is stuck, it may require that the downpipe be removed and the bolts holding the turbine discharge pipe to allow inspection of the rear part of the turbine and the small wastegate valve right next to it. You may get lucky enough to spray some break free or liquid wrench on the iron wastegate lever arm and wastegate valve assembly(let it soak a while) to get it to actuate freely again, if not, replace the wastegate valve assembly. It is bolted to the end of the turbine itself by I believe 5 or six bolts. If the wastegate arm moves freely open and closed/back and forth: Another problem is that the wastegate actuator boost pressure line is blocked or not connected to an adequate boost source to allow the actuator to open and move the rod open or closed. Or the internal wastegate arm actuator has an internal leak and even if boost pressure enters it, it leaks before it builds enough pressure to compress the spring to move the wastegate actuating lever arm. If that is the case, it needs to be replaced with a new one. HKS and some other manufacturers make great replacement internal wastegate actuators if that is indeed the problem. Hope this helps isolate the excessive boost out of control problem.

5-speed conversion done, installed better and lighter seats. Finally have all the parts and mocked them up on the engine and they fit with some modifications to the TO4e internal wastegate bracket mounting. Looking forward to a test fire, tune, drive, tune, drive, tune until the bugs are worked out of the Demon blow through carb turbo set up. Looking to do a test run at Top Gun raceway in Fallon to see what she will do on October 17th if all goes well....