madkaw

My son wants to stay for nationals - which is next week. I don't have that kind of vacation left. I'm aware of Zcon which is killing me. One week sooner would have been perfection

But I haven't seen one Z yet:( I thought this was where they were hiding! It is freaking hot out here. No wonder you CA boys are adamit about getting AC. Freeways are crazy as well as the drivers - I think I will stay in indiana , but definitely liking the visit. My boy is swimming Jr. Nationals in Irvine. Oh - we also had our first run in with the CHIPS! Boys jumped in the car after the meet and we went a block and the CHIP pulled us over for no seat belts in the back. Welcome to CA

No updates except frustration! On vacation in Irvine CA right now-so stepping away and also waiting for parts from Todd. I need to do more carb swapping- as far as position- to verify my issues.

You have to have a car that idles well to have AC. Doesn't sound like your engine as is will support an AC system.

It's an accomplishment for sure to make the pressurized Mikuni's work. I think the programmable ignition is mandatory to keep this builds from blowing up. I thought about pressurizing mine for a while, but since I am having issues with just NA, I think I will stick to FI for turbocharging:) It definitely looks impressive under the hood Kenny

I actually did swap carbs. I thought I found something when my #4 cylinder issue followed to the #2 after swapping the front two. Then after trying to verify with some more runs #2 looked great. That's what is making this so frustrating. When I think I have found something I can't seem to verify it. I am not totally counting out carbs and I need to get with Todd. I don't like what I am seeing inside the head chambers in 3&4 though.

So I pulled off the carbs and put compressed air to everything. Didn't see anything in these carbs that is causing my issues. Put them back on and ran the car around the block and still bad. Tested the fuel pump and she flowed good. Linkage was adjusted up and it runs the same. The issue I get is from cylinder to cylinder on the same carb-not a linkage issue. I checked the butterflies and they are in sync-measured with a feeler gauge. I pulled the intake hoping to find a bad intake gasket, but it looks great. Now it's decision time-pull the head or not. Compression is good on 3&4 with a compression tester. Really need to do a leak down, but don't think I have a compressor that will put out enough pressure. I need to check into this. Visually, 3&4 intake side of head look worse then all the others. The inside of the intake runners(inside relative to each other) have a bunch of crap on them. i will try and get a pic, but it looks like oil that is coming from the guide. That's just a wild guess.

Well after running the engine again and seeing #4 draw much less air then it's next door neighbor#3, I decided to rip them all off and pull the intake too. Of course the intake gasket was fine, which I thought it would be. The car didn't run it had vacuum leaks, but I'm getting desperate. I did check the butterflies on 3&4 and they matched up beautifully. Now I stare at my engine thinking what;s next. Not much in the way of evidence to justify pulling the head, but I think my carbs are okay. I did notice looking down in the intake runners of 3&4 that there was a lot of soot? on the inner walls of both cylinders. When I say inner, I mean in respect of each other. No other cylinders look like that. Kenny, I fought transition with these carbs and thought I won with the bleed pipe mods. I don't think those mods have anything to do with my issues now. I would try and go as big as possible on my pilots if I were you. I don't understand why my motor/cam wants such big pilots, but it works well. I think it is mostly the Schneider grind, but I've run 70's on my motor. I run 67.5's now and it's just a L24!! The bigger pilots might help you bridge the transition gap better, then maybe drop your main air's. I have smaller main airs if you need any. I bought all the way down to 160's to fight the transition issue. I'll never use them.

It seemed that a fatter idle made for easier start ups for me, but if you can get away leaner-go for it. Don't forget Mitchell, he is boosted. Want to keep things on the rich side.

The short answer -No:( I messed the carbs all day. After seeing #2 looking fouled I decided I needed to tear them all down and put some compressed air to things. In the process I didn't see anything that I could attribute to any of my problems. There was the slightest bit of sediment in the bottom of the carbs. I put everything back together and and got it running. It's still not right, but once again I can put my finger on it. When I went to synchronise the carbs #4 was hardly drawing air compared to #3. It was off by quite a bit. The engine didn't idle to terrible, but not like it used to. I finally just said WTF, I'll drive it and see how it feels. Well it still not right, hell it even back fired once getting on it. Seems to be lacking power . The AFR's didn't jive with the known jet settings and they seemed a bit erratic. I pulled the plugs afterwards and none were fouled and they didn't look too bad . Not sure what I'm going to do next. I will probably drive it again tomorrow weather permitting. Getting really discouraged and pissed with the whole matter. This seems to be dragging on to the point that i don't remember how I got here. This car used to run fantastic.

With these cars - value is in the eye of the beholder. Now if you were dropping a v8 in a Ferrari- then you might worry about values

Wow- hope it's worth the wait! It seemed forever to get my engine done locally, but in comparison I guess it want too bad. But my head was serviceable ! Just grabbed another e-88 for spare too!!

So a little history please. Was it running fine before? Might just start looking at the basics and going from there. Check for tightness of all fasteners , return springs , linkages.

Seems okay and working right are two different things. If he worked on Datsuns he knows that these dizzys screw up --a lot!! Simple test to accomplish - pull vacuum hose, plug, drive:)

You might be on to something with wanting to check the dizzy. Those years are prone to issues regarding the vacuum advance. You might try disconnecting the vacuum portion of the advance and try driving it . The plastic parts of those dizzys break and cause the vacuum advance to malfunction . Check what scale you are on with your ohm meter. You were probably reading 2.7 ohms

I don't know if I would say that about going back to 70's technology. FAST is no joke engine management and there is probably a lot of support available on that general systems. The FAST system would be worth making work. Any wiring for the chassis for a 73 should be a pretty simple task.

Definitely not your ole carb tune stuff. I guess if it runs good it would make a nice platform to finish up . It's always a bit of a gamble on a performance modded car like that. You have no FSM to fall back on. If you have a strong mechanical background and don't mind chasing wires, you might be alright. Since the price seems based on a performance upgraded Z - it would have to run and drive good for that money .

Don't forget that having the crank in a certain position allows for more clearance when wedging pan between the crossmember .

Find the download for the FSM for the car and get your ohm meter out and start checking everything . CHT comes to mind for your issues.

Your mention of solder was noted and it has been on my mind. I know my bleed pipe alterations are still in tack, but wonder if loose solder from previous attempts have made their way somewhere not good. I tried to be careful but might have gotten sloppy and not cleaned up properly and now have solder blocking a passage. I'm not too far from breaking the carbs all down anyway. Cursory inspection shows clean as a whistle

Jim, I appreciate all the input-truly. Not sure that isn't one of those deals that I have made worse by trying to fix the wrong thing with an adjustment here or there. I will eliminate the possibility of a faulty fuel pump when I get back to town . I will do volume test there. I also need to make sure any linkage issues are resolved. This has just been a total kick in the balls for this summer. Too many nickle and dime issues already and this just takes all the fun out of my hobby. Thought I would be at the dyno by now and pushing forward on my custom FI project. Hopefully walking away will reset my attitude. I about have to take a week off since the family is going to CA for a week.

Magna flow turbo . Go as big as you can fit. I'd run a second resonator and run all 2.5 or 3" pipe

Don't forget your springs. I bet you have custom springs for that cam.

Not conclusive or thoroughly investigated , but though it is a problem I don't think it's my overall issue. I only had a little while to play after discovering this, but it wasn't the night and day difference I expected. The jury is still out. These carbs did/have run beautifully with te response of a sport bike when blipping the throttle. I would never consider cable option as well as throttle feels and works. Another thing I noticed and don't want to read too much into is the amount of condensation dripping from my exhaust. It hasn't been that humid here but I have been doing a lot of idling. The drips don't seem to ever stop. Looks like water only.

I've watched my fuel pressure gauge when i can(in the engine compartment),but that might not tell me if I have a flow problem.Nice thing about the MS is I can turn my pump on without running the car. So I will measure that next to make sure I am getting adequate flow. It makes me think pump when I watched the AFR's slowly bobble to the lean side. I did discover that my rod linkages needed work. I was just flipping the throttle while leaning over the fender and noticed the levers not at the same exact moment. In fact one of the ball socket ends is worn which allows for movement without throtlle action.