Jarvo2

My paint guides only go upto '74, but you might be able to talk to PPG and give them the paint #.

It’s the lack of backpressure with the new exhaust. Stick some steel wool in the exhaust tip and the popping will most likely go away until it falls out. You’ll also loose you HP gain by limiting the free flowing of the exhaust. As many other members have Pointed out, a 40+ year old car is not going to perform like a modern car!! Sent from my iPhone using Classic Zcar Club mobile

Gotta love when they put a rocket booster in one for a stunt & jump it in The Fall Guy. http://www.imcdb.org/vehicle_487814-Datsun-240Z-S30-1970.html

Why did you remove it in the first place? Trying to give yourself more problems? Sent from my iPhone using Classic Zcar Club mobile

Buy yourself a new pertronix, the directions say to leave the tape on. Sent from my iPhone using Classic Zcar Club mobile

Depends how fancy you want to get! I just put a generic one in front of the radiator http://2.bp.blogspot.com/-T9pOrMbIbHA/VBMlDVNrisI/AAAAAAAAA5k/UCBcfak2sOE/s1600/IMG_0495.JPG Sent from my iPhone using Classic Zcar Club mobile

If you're running electronic ignition, either pertronix or a matchbox, eliminate the ballast so you get the full 12 volts at the spark plugs! The. Ballast is only in there to prevent burning out your points Sent from my iPhone using Classic Zcar Club mobile

Are those parts made of gold? Sent from my iPhone using Classic Zcar Club mobile

Would a more restrictive muffler provide better back pressure? My msa premium exhaust is very free flowing, although I get no popping with my 2.4L and original cam on my 72 Sent from my iPhone using Classic Zcar Club mobile

I was always told that you can't just let them sit & measure the 9/16". You need to blow through the float bowl hole (through the needle valve) and make the 9/16" when the valve closes.

Head & Camshaft! Even MSA says that a hot cam is for racing "Performance camshafts are intended for racetrack". A hotter cam will not idle like a street car, its designed for output at higher RPMs! http://www.thezstore.com/page/TZS/CTGY/classic12e03

I picked up some used chevy caviliar doors seals and they worked great. Sent from my iPhone using Classic Zcar Club mobile

I had a colortune and it was nice at idle but couldn't see what was happening while driving on the street. Also with modern unleaded gas it's difficult to base everything on the color of the plugs. Sent from my iPhone using Classic Zcar Club mobile

Talking about the Air/Fuel ratio that can be measured by a wideband oxygen sensor. https://smile.amazon.com/AEM-Combo-30-4110NS-Bosch-30-4110/dp/B01F46VJ4U/ref=sr_1_2?ie=UTF8&qid=1497022242&sr=8-2&keywords=wideband+o2+sensor+kit

Jalexquijano: Have you tried a water wetter in your cooling system to lower the temperature, and have you also burped the system to make sure there aren't any air pockets that are allowed to get super hot? Water Wetter example: https://www.redlineoil.com/Products.aspx?pcid=10

They're one in the same. Msa gets it from Wesco. No the factory seatbelt warning system only works with the original seat belts unless you design & build your own way to hook it up. Sent from my iPhone using Classic Zcar Club mobile

No, you need to replace the belt & the receiver with the MSA kit. I recently sold my set because the receiver flopped around & was quite a pain to use! Here are some pictures of what I installed with the MSA kit: http://jarvas240z.blogspot.com/2013/08/seatbelt-upgrade.html

This is a video of my 240z once it was tuned & running perfectly (post engine rebuild). VacGauge.MOVVacGauge.MOV

No vacuum leak, but rather a health check for the engine. You can very easily tell if you have a leaking valve, carb's out of sync, broken ring, bad timing, blown headgasket, etc. Please see below:

Several other items to check on your quest for idling without RPM dropping... How is your fuel pressure? Have you actually checked it with the engine running once its warmed up? I plumbed in a cheapo gauge and am getting A steady 2.0 GPH out of my electric pump, which is right where it should be for carburetors. Could your pump be pushing more fuel then your needle valves can support within the float bowls & making the carbs run ultra rich at idle? At cruising speed, it wouldn't be noticeable as the fuel is getting burnt at higher RPMs. How is your engine vacuum? Again, plumbed in a cheapo gauge into my balance tube & am able to confirm the health of the engine very quickly at idle and higher RPM. Reference https://smile.amazon.com/gp/product/B00GM5FPXO/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

Yes, remove it. Its the pre-heater for the airbox to be used in colder climates (look at the summer/winter flapper on the orange airbox). This is what it looks like once its off. It probably isn't doing any harm, but isn't doing any good either for your situation.

Have you ever considered getting a used head with the stock cam and having it rebuilt by a reputable local engine shop? I still think the root cause of this problem is the California Datsun / Datsun parts LLC engine and head combination that you're running. You're throwing good money at bandaids and not fixing the cause of the overheating. Sent from my iPhone using Classic Zcar Club mobile

This is one of the best ones I've seen! https://zcardepot.com/tools/carburetor-float-sync-tool-su-240z.html

Dr. Googles says "Mufflers deal with temperatures that range between 300 and 500 degrees fhreneheit. Due to the intensity of heat produced by an engine's emission system, most exhaust systems are built to handle an excess of 1,200 degrees. In addition, Gasoline exhaust gases burn in the range of 1,000 to 1,400 degrees Fahrenheit."

These spacers are available in the 4x4 world all over the place for raising (leveling) a truck out. I've heard great things about the billet spacers & am looking at a set for my xterra, although I haven't pulled the trigger yet. I would have to think that this will resolve the problem you face with the rear sitting lower in the 280z