Vapor lock questions for the hotter climate guys

[siteunseen]

7 hours ago, jalexquijano said:

Is there any posible way of keeping the rpm stable at 900? The car is not stalling but this sudden rpm fluctuation feels unconfortable when driving and getting stuck in traffic jams.

[psdenno]

23 minutes ago, jalexquijano said:

Please let me know when you come so i can show you my car and maybe a trip to the new set of Panama Canal Locks!

Thank you for your generous and hospitable offer.  Are you near Colon or on the Pacific side?

Dennis

[jalexquijano]

On ‎12‎/‎20‎/‎2016 at 0:26 PM, psdenno said:

22 hours ago, psdenno said:

Thank you for your generous and hospitable offer.  Are you near Colon or on the Pacific side?

Dennis

Pacific. Panama City. I would like you to see my car and let me know your thoughts on how to get rid of this 900 to 500 sudden and random rpm drop when the engine is at idle during extended time.

 

22 hours ago, psdenno said:

Thank you for your generous and hospitable offer.  Are you near Colon or on the Pacific side?

Dennis

utting it in a pan of water along with a cooking thermometer and heating it to see if it opens at the proper temperature.

As for Datsuns in Panama, I'm surprised there weren't a few Zs brought in by US military members stationed there or Americans working for the Canal company during the 1970s.  It's been a few years since I was there but plan to visit again in April.  Interesting that the local Nissan dealer won't supply parts for a Datsun.  My local deal never sold Datsuns, but is happy to provide parts for my Z if they are still available in the supply system.

Good luck with the ongoing project.

Dennis

Please let me know when you come so i can show you my car and maybe a trip to the new set of Panama Canal Locks!

[jalexquijano]

On ‎12‎/‎20‎/‎2016 at 10:43 AM, Mark Maras said:

 Need a few more puzzle pieces. When the idle drops to 500, and assuming you instinctively hit the throttle to compensate, is there any stumble or hesitation? Also assuming that you revved the engine to compensate and let it fall back to an idle, did the idle return to 900, even temporarily or did the idle go back to 500?

it does not fall back to 500 rpm. It keeps the rpm range from 800 to 900 rpm. My car does not have the original 240z cam. it has a Schneider 274F cam to compensate the overboring of the cylinders. i did noticed that if i open the Hood and leave the car in idle at the parking lot the idle becomes smoother. Anyway of getting the rest of the heat out from the car to help during traffic jams?

[Mark Maras]

 When you pop the hood, how long does it take for the idle to smooth out and is the temp gauge dropping as the idle improves? Did you bypass the stock fuel rail on the engine with a flexible fuel line yet?

 Assuming the plugs now look somewhat normal in color (tan-ish, tell us if they're not), What radiator and fan combo are you running? Specifically, the number of rows in the rad and if you're using a clutch fan, does it have much resistance in the clutch? On my first Z I found that a larger capacity rad (3 row) and a flex fan stopped my overheating problems on those blistering hot (100`+) days sitting on I-205 during rush? hour. Before that fix however, I found that shutting off the engine even briefly instead of idling would delay the overheating quite a bit longer (it always started with a click of the key) and on a few occasions I turned the heater and fan on high to help drop the engine temp. Not much fun in a Z with a black interior, no louvers and 100`+ heat but anything to save the engine, which it did.

 

[Zed Head]

21 hours ago, jalexquijano said:

It keeps the rpm range from 800 to 900 rpm. 

What is the rate of this fluctuation?  In other words, how long does it take to go from 800 to 900 and back to 800.  How much time from 800 to 800?  One second, two seconds, less than a second?

[jalexquijano]

On ‎12‎/‎27‎/‎2016 at 6:30 PM, Zed Head said:

What is the rate of this fluctuation?  In other words, how long does it take to go from 800 to 900 and back to 800.  How much time from 800 to 800?  One second, two seconds, less than a second?

let me check! Im still with the original metal fuel rail. Trying  to keep the vintage look!

[Patcon]

If you are stubbornly going to try to keep the "vintage look" then get use to fluctuating idle rpm's

[siteunseen]

And get rid of that shiny aluminum radiator. 

[sweatybetty]

2 hours ago, siteunseen said:

And get rid of that shiny aluminum radiator. 

[jalexquijano]

20 hours ago, Patcon said:

If you are stubbornly going to try to keep the "vintage look" then get use to fluctuating idle rpm's

do you think that thermal cloth i wrapped around the metal fuel rail is doing anything to lower the gasoline temperature? Should i remove it? it looks silly and if aint helping with the fuel percolation i might as well remove it.  

[Patcon]

3 hours ago, jalexquijano said:

do you think that thermal cloth i wrapped around the metal fuel rail is doing anything to lower the gasoline temperature? Should i remove it? it looks silly and if aint helping with the fuel percolation i might as well remove it

JeffG told you how to bypass the metal fuel rail a long time back. He is a Ford engineer and races cars, maybe you should take his advice...