Jeff G 78

It's a common swap and works without any problems, but if your oil pressure is already on the low side due to worn bearings or pump, you could possibly run into oil pressure issues. Either swap in a turbo pump or install spray bar block off plates. MSA sells them. Be sure you keep the rocker arms and lash pads with the cam as a set. Swapping cams and using the old arms will cause premature wear problems.

Thanks for all your help Bruce. The old SUs worked great when they had fuel in the bowls. :stupid: We didn't mind using race time to fix it since we finally did fix it. It's the first time in the year that we've owned the car that it has actually performed well for any length of time. I really don't understand WHY we had the problem we had, but we aren't worried about that right now. We were happy to finish the race strong.

Thanks Marty. I haven't looked at the pads, but I'd guess we might be able to get another race out of them. We really need to find more power. We are getting killed on the straights. After about 10 hours, we picked up a valve tick. We pulled the cover and found that a lash pad had come out. I had just adjusted them prior to the race, so we might have some weak springs. We might throw rings and bearings in it before the next race to freshen it up.

We just got home from GingerMan Raceway after completing a 14+ hour endurance race with our $500 BRE tribute car. The lighting was perfect, so we got some great pics at the track Friday night before the race. We completed the 14 hour race on the 36 year old original rotors and drums. We only changed the front linings to Porterfield R4-E and the rears to R4-S. We used MSA SS brake hoses and Ate fluid. We had zero brake issues the entire race and never even had to blead them. It's amazing what 10.8" solid rotors up front and drums in the back can do! Ever since we bought the POS car, we've had fuel issues. We thought we had everything sorted prior to the race, but it still ran like crap. After trying many other things, we clamped a pair of Vice Grips on the fuel return line and the car ran great for the remaining 11 hours. We didn't finish high in the standings due to the fuel troubles early, but once we got it figured out, we ran consistant laps. The last 3 hours or so were in the dark. We had to play with headlight aiming to get the corner entry points illuminated, but from then on, it was a LOT of fun. Night racing is a whole new game. We were able to run four 60W lights with the stock and very old 50 amp alternator. They were super bright even at idle. Special thinks to Ron (geezer) for supplying a distributor and to John at H4Lights.com for supplying the main lights.

Update: Bruce wins the "smartest guy in the room" prize for correctly calling the problem as a clogged pickup sock in the tank. We diagnosed the problem by swapping the two fuel hoses at the tank using the return as the supply and the supply as the return. We did an A to B and back to A test and confirmed the diagnosis. We have no way of fixing the tank, so we'll just race it using the return line as the pickup. We lose some range since the return isn't on the tank bottom, but it's better than heading into the pits every five laps with starvation issues. Here is a pic of the return pipe in the tank. You can see how the retun is up off the bottom. The supply is out of view on the far side of the baffle, so we had no way of knowing it was clogged. I did blow through it when I POR15'd the tank, but it could have been full of crud and had just enough free area to run fine for a while until the rest of the sock filled with debris, limiting flow. After the car would sit for a while, enough crud must have fallen off the sock for it to run well again for a short time. Thanks to everyone for all the help!

Thanks everybody for your quick help! I plan on borrowing Geezer's ZX dizzy to try. The big question is what does everybody think the problem is? Is the distributor a likely culprit, or am I barking up the wrong tree? I want to have as many possible fixes in my pocket as possible. I hope the dizzy solves it, but if it doesn't I want to be ready with other things to try.

Thanks Stephen, that makes me feel better. Give me a few minutes and I'll have all the info I need. Now, where is that search button???

Uhhh, you are scaring me. I need to go read up on this stuff.

That would be awesome Ron! One of my teammates lives in Windsor and usually comes every weekend to help us work on the car. If he's coming this weekend, maybe he could grab it from you on his way here. I guess I'll have to do some quick research and see how hard it is to convert to that setup.

Z train, forgive my ignorance again, but what exactly does the MSD replace? The '75 dizzy + MSD 6AL and I'm all set, or do I need other components? I know Z cars rather well, but I've never messed with distributors much.

I couldn't *feel* any shaft play, but it doesn't mean it doesn't have some. There is nothing in the rules stopping me from swapping to a GM HEI, but I just haven't done it before so I'm a bit ignorant. Could I use my spare '75 distributor for the GM swap? I always hear people talking about ZX distributors with GM HEI. I have no access to a ZX distributor unless I have one shipped from someone with a spare. I have a spare '75 dizzy and the dizzy in my '78 "good" Z. The '75 dizzy could be a permanent solution if I can make it work, but that engine last ran 17+ years ago, so ??? My '78 is in good working order with a newish pickup coil, but it can only be borrowed so I can drive that car after the race is over.

I've talked to a few more people and I might have gotten some good advice. My buddy who is a powertrain engineer at Ford listened to my tale and he's pretty sure the problem is ignition. Specifically, the distributor. He thinks that something is getting hot and I'm getting weak/no spark under load. Since the plugs look sooty after I come in from the track, he thinks that I have plenty of fuel, but a lack of spark causing the plugs to read rich. In reality, they just don't have the spark to fire. Also, since the bowls always look to be the proper level and the filters stay full, we shouldn't be experiencing the stumble when we first accelerate out of the pits. We should have gotten at least one straightaway of good running before the bowls got low. Instead, it coughed right from the very start of acceleration. Now, assuming he is correct, what are my options? I have a '74 260 in Michigan and I need to be fully repaired in 5 days before leaving for the race. Getting a 260 distributor will not be easy or cheap. I have a '75 distributor, but no transistor ignition unit from a '75. I'm not sure if they are functionally different, but the P/Ns don't match. My other option is my '78 280Z. In it, I have a perfectly working stock ignition system. I can steal the distributor and transistor ignition unit from the '78 for the 260, but what else do I need? Will my '75 tach work? I assume I'll have to make a new harness between the distributor and the TIU, but what else am I missing? I REALLY don't want to have to cut any connectors off my '78, but I will if I have to. I have a lot of money and time tied up in this race and I cannot fail now. I'd rather rewire my '78 after the race than throw all this prep time and money away if the 260 doesn't run right. Ideas?

We are running the stock fuel rail with return that has the small orifice in the outlet to regulate pressure. We plan to add a pressure plumbed to a gage mounted on the hood.

Yes, we are running NGK BR-6ES-11, I think. I'm going from memory. They are the normal Z plugs everybody runs.

I am out of spit and I only have a few days to figure out and fix the problem with my 260Z LeMons car or I will have a very long, frustrating race next weekend. I'm asking for thoughts you have. The biggest issue we have is that it's a track-only car and we cannot prove out anything we try until we are in the race next weekend. Here's the story: Car setup: '74 260Z with 3 screw SUs on a 260 intake and stock exhaust manifold Fuel tank was cleaned and POR15 treated and has two fuel filters that stay clean Engine has good compression SUs were cleaned/rebuilt and SM needles installed. Floats set to spec and they synched at idle and 1500 RPM Pistons drop at same rate and needles move smoothly up and down in choke seats New mechanical fuel pump - electric pump removed New fuel hoses and vent lines All hard lines flushed and checked for blockages Stock magnetic pickup distributor with working vac and mechanical advance Extra heat shielding between exhaust and intake and fuel rail well insulated Performance coil running at full 12+V (no ballast resistor) No EGR or water lines to intake manifolds New MSA radiator with gutted thermostat The sympoms: Car starts immediately and idles perfect as low as 700 rpm Free revs smoothly to 5k+ rpm Runs great on roadcourses for 10-20 minutes with zero issues After 10-20 minutes (depending on air temp), car begins to stumble at 4k rpm. Within a few turns, the car hits a brick wall at 4k and will not rev higher Backfires through exhaust 2-3 times on decel after a stumble Runs worse and worse and within a few turns, car will not accelerate at all Continues to free-rev to 5k+ without missing Sometimes after car cools for 30 minutes or more, it will run well again for 10-20 minutes and other times, it continues to have issue Car always free-revs fine and always restarts immediately and idles smoothly What we've tried: Checked fuel inlets at carbs, checked/replaced filters, floats, etc Symptoms did not change with/without SM needles Plugs are all the same and rather black after a stumble incident Replaced Transistor Ignition Unit immediately following stumble Removed gas cap to rule out tank vent issue Ran car without hood to aid airflow to fuel lines in case of vapor lock Replaced coil, spark plugs, plug wires Our thoughts: We are fairly certain the problem is heat related as is is worse when ambient temp is higher and only happens after car gets fully up to temp We *think* the problem is fuel related since it's only under load. If ignition, would the car free rev OK? We think the problem is in fuel delivery and not in the carbs since the plugs all look alike Our next steps: Install an electric fuel pump in addition to mechanical pump Add fuel pressure gage so we can monitor pressure Recheck mechanical advance in distributor Like I said earlier, the car free-revs fine and it only happens under load, so we have no way of knowing if a fix works or not until we are on a track for 10-20 minutes. Our next opportunity will be DURING our race next weekend. We plan on trying anything and everything we can do in one week, so I'm open to suggestions!

I run 195/60R14 Falken RT-615 tires on my LeMons 260Z and they fit and look great. The rims are 6" wide and the car is lowered about two inches. If anything, they would look better on wider rims. They might look really small on a stock height Z.

Really? I didn't know that. I asked here once before if it was and I was told NO. At least now I know that I can buy the MSA exhaust and it will bolt up to my AZC header.

Arizona Z Car makes a good 6:1 as well. Nice thick flanges and well designed. Mine is a bit close to the TC rod bushing heat shield, but that is probably fairly typical of 6:1 headers.

I assume the smell is rather uh... strong? Been there, done that.

When I was searching for shank style lugnuts, EVERY parts store had the M12x1.5, but very few had the M12x1.25. Call around to good mom & pop wheel shops and you should find what you need. I think they even had them at Autozone and other chain parts stores.

Very cool Ron! Your Z looks fantastic on the track.

Shade133, there are a ton of Z guys and gals in Phoenix. Go to http://www.desertzassociation.com/ and ask for help. They are a great bunch. I was in Phoenix once on business and dropped them a post on their forum asking when they meet. Within a few hours, they scheduled a meet for the night I was in town and close to 20 Zs showed up! It was the middle of the week too if I remember correctly. I haven't seen a total of 20 S30s in Michigan since I moved here 16 years ago.

I have one car with each and they both have their places. The FI is great if everything is in perfect working order - same as the twin SUs. At least with the carbs, you can call Bruce Palmer and order a set of beautiful rebuilt SUs that will run great for years. With EFI, you will have to diagnose each component and connection yourself and might get frustrated trying to get it all working properly. Either will work fine if they are working properly and both suck if not.

If the car isn't rusty (which a CA car shouldn't be), the tank drops rather easily. Rusty cars are harder due to the long strap bolts which tend to be a pain. The hoses WILL be hard and tough to get off so you need to try very hard to salvage them unless you plan on replacing them. Once the tank is down, the cleaning and sealing process is a pain in the butt, but it can be done and does work. I have done two tanks with POR-15 and both came out great. To do it right, it takes about a week once the tank is down and costs about $80 if you do it yourself. If you go this route, you MUST follow the directions exactly and even go a step further if needed to preclean before starting the POR treatment.