Carburetor Central

I am the proud new owner of a 1970 240Z HLS3003137 but am not the most mechanical person yet (but working on it). The car does not run too good yet and I think one issue is the carb tuning. I have 2 questions: 1) I changed spark plugs and the old ones were covered in black soot. When I start the car soot shoots out the tailpipe and you can barely detect that the exhaust is a bit black. Is this simply a too-rich fuel/air mixture or are there other possible issues? 2) I plan to get an airflow meter and tune the carbs. Before I do that I need to set the proper idle speed. My question is on the default position of the choke because that seems to be influencing my idle speed a…

I have been driving my Z a bit with a wide band 02 installed. Generally speaking, the car is rich at idle and lean everywhere else. If I am not mistaken, the needles I have are the stock N-27. I cannot confirm because they have not markings. After reading the following post, I got to thinking... If I have the needle station measurements, and I can record my AFRs for each of the general categories of start, idling, pick up, cruising, and top speed, then might I be able to calculate the station measurements of the needle that my engine wants?

hey guys. so i'm starting to get the ball going and start working on my 5/74 260z before actual rain starts. got some bumps. the whole fuel system is off and is gonna go back on after the front suspension is on and the tank gets cleaned. everything looks stock. it doesn't seem to make sense to me to use the same hoses after carb work. the hoses still look good but 40 years seems like a long time running. and a new mech fuel pump wouldn't hurt. so it got me thinking about a clean fuel system, or as clean as i can. so two things on the front. how do i clean the hard lines? the wrapped ones and the rails along the side that go to the rear. just straight flushing? the other i…

My 240Z ran when I got it, but poorly. I took the carbs off and cleaned them by removing the suction chamber, piston and float assembly and spraying with carb cleaner and soaking small pieces in Berrymans. And wiping and scrubbing with a toothbrush well. I checked the adjustment on the floats and they were fine. I left the other adjustments as they were. Now the car won't start. When you crank it with the starter the car will rev-up but when you let go of the key the car immediately dies. I thought that if the car ran with dirty carbs, just cleaning them would at the very least help a little. Any thoughts why it won't start? Thanks, Steve

Cleaned up the gas tank and removed the evaporation tank Removed evaporation tank cleaned up the Gas tank and put it back together. I used a tank restore kit from Hirstauto: http://www.hirschauto.com/prodinfo.asp?number=ARK-01 . The outside of the take is painted with Hirsch Miracle paint: http://www.hirschauto.com/prodinfo.asp?number=MIR-QUART Cleaned, sanded, etched, rinsed and dried a bunch of times. I found 1 hour with a heat gun set on low stuck in the gas inlet dried it well. Followed all the instruction on the gas tank kit, except: I cleaned the tank with Muriatic acid first to remove the rust (there wasn’t much rust but I fixed it anyway). Use all appropriate…

hey, does anyone know how you are supposed to clean the reusable k and n air filters? thanks for your help, brian

Hey guys, My Z's PO converted her back to the original SU's after the owner before him had put on dual Webers with Cannons and K&N filters. So I inherited those carbs, runners, and filters and it's all pretty much in pieces. I'd like to clean them up and reassemble them. My question is what should I use to clean them? I've heard the chemicals can be pretty expensive. Any ideas?

Hello I am going to replace all my fuel lines and possibly my fuel rail. I used to have clear tubing on my old 510 that worked great and wanted the same on my new Z. I am going to use 1/4" from the main hard line and was told that the tubing is fuel rated PCV but I can not find any and did not want to just use water rated PCV. Does anyone know where to get 1/4" clear not yellow fuel safe tubing? Also what ID/OD is the SU jet tubing since I want to replace that as well as add a float level tube. Thanks.

Making sure this is alright due to using parts from a 71 and a 72. I have a E36 intake manifold (believe this was from a 71), no water jacket going to carb. Then I have the 72 insulators with the water jackets. Going into the 72 SUs with water jackets. Ok, now for the air box side of the SU's, I have the 2 air ports at the top which I believe feed the damper. But my air box only has the one opening for the air port. Does this all seem compatible? I am currently not running the water line thru the intake, so I do not suppose there is an issue with the insulator but wondering if I should be using the earlier insulator with no holes. And for the air box onl…

away from heat easy access to carb tops

I have a Clifford intake and a holley 650 carb and it's running rich, do i need a smaller carb for the intake?