Lucas Grey Posted March 7, 2021 Report Share Posted March 7, 2021 Hello! I just bought a 1979 Datsun 210 last week and know little to nothing about the car itself. I have a few friends who have owned them in the past, and when I mentioned that I was struggling to pass 50-55mph on the highway they were very confused. I was told that my car should be going significantly faster than it is right now. I am running 13 inch wheels but that should not have that much of an impact on its speed. I have a 4 door with a four speed manual and the 1.4L A14. I've done very little to the car other than fix the timing. I have fully stock internals. I'm guessing that it could be a bunch of small issues and I am planning on starting by re-building the carb. I also think its important to know that I have ruled out the idea that the gearing has been changed as I have very little torque throughout my entire rev range. If anyone has any suggestions or has experienced the same let me know! Quote Link to comment
datzenmike Posted March 7, 2021 Report Share Posted March 7, 2021 Tire diameter is more important than rim diameter. Depending on the rubber you select you can run 14" or 15" rims and they are the same height as the stock 13" tire. There's just more rim and less tire wrapped around it. Replace the fuel filter. Only a few bucks and if it doesn't help it's due to be changed every 3 years anyway. Engine off, hold the throttle full open and push the secondary vacuum diaphragm linkage open to make sure it isn't stuck. Engine off hold full throttle and look down the primary barrel with a flashlight to see if the throttle plate is vertical and fully open. If not adjust the throttle cable slackness. Are you sure about the timing? You have the correct advance on the scale? You could try advancing it several degrees at a time to see if it improves. I would guess 8 to 12 degrees on an A series engine? 1 Quote Link to comment
Lucas Grey Posted March 7, 2021 Author Report Share Posted March 7, 2021 Im not sure the exact degree that the timing was changed to. I don't have the device so I took it to my mechanics shop. I am pretty sure there might be an air leak in the carb but nothing is stuck and everything is opening up fully. I will try the fuel filter and see what it does. I'm also guessing it could just be compression due to a leak that I might have. Quote Link to comment
Lucas Grey Posted March 7, 2021 Author Report Share Posted March 7, 2021 18 minutes ago, datzenmike said: Tire diameter is more important than rim diameter. Depending on the rubber you select you can run 14" or 15" rims and they are the same height as the stock 13" tire. There's just more rim and less tire wrapped around it. Replace the fuel filter. Only a few bucks and if it doesn't help it's due to be changed every 3 years anyway. Engine off, hold the throttle full open and push the secondary vacuum diaphragm linkage open to make sure it isn't stuck. Engine off hold full throttle and look down the primary barrel with a flashlight to see if the throttle plate is vertical and fully open. If not adjust the throttle cable slackness. Are you sure about the timing? You have the correct advance on the scale? You could try advancing it several degrees at a time to see if it improves. I would guess 8 to 12 degrees on an A series engine? Im not sure the exact degree that the timing was changed to. I don't have the device so I took it to my mechanics shop. I am pretty sure there might be an air leak in the carb but nothing is stuck and everything is opening up fully. I will try the fuel filter and see what it does. I'm also guessing it could just be compression due to a leak that I might have. The engine is seems to be running pretty rich so I think that reinforces that possibility. Quote Link to comment
datzenmike Posted March 7, 2021 Report Share Posted March 7, 2021 When warmed up take the top off the air filter and look at the choke plate. It should be vertical and fully open. If the choke hasn't opened this would also limit top speed and performance. Running excessively rich would blacken the spark plugs and you might see black smoke out the tail pipe. Quote Link to comment
Ranman72 Posted March 8, 2021 Report Share Posted March 8, 2021 it is also possible the catalectic converter is plugged just another possible option 1 Quote Link to comment
KELMO Posted March 8, 2021 Report Share Posted March 8, 2021 It is also possible that because it is an "A" motor, it just won't go any faster (sarcasm font). I know this because I have a few. Have you checked compression? What do the spark plugs look like? Quote Link to comment
datzenmike Posted March 8, 2021 Report Share Posted March 8, 2021 I had a B-210 and it would easily do 75-80. 55-60 isn't right. Clapped out is also a possibility. LUCAS GRAY... 1/ When you are getting up to speed does the car surge ahead then drop back, like stepping on and off the gas??? 2/ Does the car use a lot of oil? Does it smoke when driving? 3/ Is it an automatic? Quote Link to comment
Jesse C. Posted March 8, 2021 Report Share Posted March 8, 2021 One way to make it faster..... 1 1 Quote Link to comment
Lucas Grey Posted March 8, 2021 Author Report Share Posted March 8, 2021 19 hours ago, Ranman72 said: it is also possible the catalectic converter is plugged just another possible option its supposed to have a cat but unfortunately for me the guy who sold it to me did a full straight pipe so I don't think that would be the issue. Actually... could that effect it in some way if he only did that and kept the smog equipment thats under the hood? Quote Link to comment
datzenmike Posted March 8, 2021 Report Share Posted March 8, 2021 No not nearly enough to affect the running. 9 hours ago, datzenmike said: I had a B-210 and it would easily do 75-80. 55-60 isn't right. Clapped out is also a possibility. LUCAS GRAY... 1/ When you are getting up to speed does the car surge ahead then drop back, like stepping on and off the gas??? 2/ Does the car use a lot of oil? Does it smoke when driving? 3/ Is it an automatic? Quote Link to comment
Lucas Grey Posted March 8, 2021 Author Report Share Posted March 8, 2021 9 hours ago, datzenmike said: I had a B-210 and it would easily do 75-80. 55-60 isn't right. Clapped out is also a possibility. LUCAS GRAY... 1/ When you are getting up to speed does the car surge ahead then drop back, like stepping on and off the gas??? 2/ Does the car use a lot of oil? Does it smoke when driving? 3/ Is it an automatic? It's a very interesting feeling while driving. Once I got the timing fixed I got a little more power and a quicker response time on the throttle. It does not drop back at all and I have no low end or high end torque. There is no smoke at all when I drive and even when I cold start the car. The engine and trans oil need to be changed along with the coolant and the car is a 4 speed manual. Quote Link to comment
Lucas Grey Posted March 8, 2021 Author Report Share Posted March 8, 2021 12 hours ago, KELMO said: It is also possible that because it is an "A" motor, it just won't go any faster (sarcasm font). I know this because I have a few. Have you checked compression? What do the spark plugs look like? I have yet to check compression and the spark plugs are a little dirty even though they were recently replaced. It definitely smells like it is running very rich. Quote Link to comment
datzenmike Posted March 9, 2021 Report Share Posted March 9, 2021 On 3/7/2021 at 7:28 AM, datzenmike said: When warmed up take the top off the air filter and look at the choke plate. It should be vertical and fully open. If the choke hasn't opened this would also limit top speed and performance. Running excessively rich would blacken the spark plugs and you might see black smoke out the tail pipe. Do the above. If the choke is on, even part on, it will run excessively rich and lack power. Choke plate closed.... bad. Choke plate fully open.... good! Without a tail pipe it will be hard to see what's coming out the exhaust. Quote Link to comment
Ranman72 Posted March 9, 2021 Report Share Posted March 9, 2021 depending on where he straight piped it does it still have the 02 sensor if that was not there or not hooked up it could confuse the computer Quote Link to comment
datzenmike Posted March 9, 2021 Report Share Posted March 9, 2021 The 210 just has a carburetor. The air fuel mixture is only adjustable by changing the jets in it. EFI can be adjusted electronically with the use of an O2 sensor for feedback. 1 Quote Link to comment
Lucas Grey Posted March 11, 2021 Author Report Share Posted March 11, 2021 On 3/8/2021 at 4:01 PM, datzenmike said: Do the above. If the choke is on, even part on, it will run excessively rich and lack power. Choke plate closed.... bad. Choke plate fully open.... good! Without a tail pipe it will be hard to see what's coming out the exhaust. Due to rain I haven't been able to check it out personally but when I took it to my shop they said there was no issues with the choke or throttle. Im going to pull carb and radiator out and send them to get cleaned and I will keep you guys posted on the results! Quote Link to comment
datzenmike Posted May 19, 2021 Report Share Posted May 19, 2021 Loss of spark to one cylinder would cut power by at least 25%. This should be easy enough to test for. Look at the spark plugs, they are a window into what is going on in the combustion chamber. Plugs, wires, cap and rotor must be in good condition so that the spark 'sees' the plug gap as the only path to ground. Loss of compression is also easy enough to test for. Adding a few teaspoonfuls of engine oil for a repeat 'wet' compression test that produces a significant increase in pressure would indicate the rings are worn. Negligible increase would indicate worn and badly sealing valves. Naturally the valve lash should be set first. Ignition timing too advanced but more importantly too retarded, will also drop power markedly. Again easy enough to check and adjust. Secondary on the carburetor not opening. 1 Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.