No tachometer in my car - want to know the rev

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Sep 27, 2006
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I have 1997 Corolla CE around 120k miles (4a-fe 1.6L ; 3-speed auto transmission). My car doesn’t have tachometer. My daily commute about 20 mile one-way, including 10 miles on highway which every body drives about 70-80mph (speed limit is 75). I always drive around 70-75 mph to follow the traffic (I can’t push to pass 75mph anyway) but wondering whether I push it too hard on the engine because it has only 3 speed auto without overdrive. I always turn the air condition off the help it. So my questions are: 1) Anyone know how much the engine rev on this 1.6 4A-FE engine? And what is the rev limit? 2) Would it helps if I use 10w-30 dino or synthetic oil instead of 5w-30 (manufacturing recommend) in the summer? I lived in Tennessee which around 100’ in summer and around 30’ in winter. Thanks.
 

tlmprnpg

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Just to correct on my first qeustion. I want to know the rev when I drive around 70-75 mph. thanks
 
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If this helps at all, I had a '92 Corolla with a 5-speed and at around 70 mph the engine was spinning around 3000 rpm. I don't know how that would translate to your 3 speed auto without an O/D. My daughter has a '96 Prizm with the same 1.6 and she also has a 3 speed auto without O/D. It seems to my ears that her engine is spinning much faster that my old Corolla did.
 
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Regardless of what you are turning, that engine will happily do it all day long. I think my redline was something like 5600 RPM and you are not getting even close to that. Give it gas and some decent oil and you've got NOTHING to worry about!
 
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You can probably find a decent little tach for around $30, so now you have a project! It must be revving quite high though, since the 5-speed is rated for 35mpg highway while the auto is 29mpg. I'm sure that little engine doesn't mind the sustained revs though.
 
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being that most manual overdrives are about .8 to 1 id say 3600-3900 at 70 ish for a non overdrive automatic using standard tires etc
 

tlmprnpg

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Thanks for reply. Any one have suggestion about my second question for engine oil.
 
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Asking for oil recommendations will get you never ending answers...everyone has their own ideas. In my Corolla, I used Mobil 1 10W-30 in the winter and Mobil 1 10W-30 in the summer but would substitute one quart of Mobil 1 15W-50 just to thicken things up a bit. I live in Texas and that little engine was hard work'n with the A/C on.
 

tlmprnpg

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I used the link that lindermant posted above to calculate it. -mph = 70 -tire size diameter = 22.74 (based on 185/60R14) -Differentail gear ratio = 3.421 (based on corolla 1999 VE model 3-speed per corolland.com) -transmission gear ratio = 1:1 - the calculator show = 3538 rpms for 75 mph rpms= 3791 for 80 mph rpms= 4043 Does these figures seem reasonable?
 
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Quote:
Asking for oil recommendations will get you never ending answers...everyone has their own ideas.
Exactly why I didn't bother commenting on that! But I will anyway now. I don't think it really matters whether you use 5W-30 or 10W-30 provided both are suitable for your coldest weather. They have to pass the same non-winter tests anyway.
 

tlmprnpg

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This knowledge let me know that it's ok for me to continue driving around 70-75mph. I tried to keep the rev under 4000. Thanks for every reply.
 
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I agree with rpn453, get a cheap tach. Then you will know for sure exactly what kind of rpm's your turning. Dosen't need to be new either. See if you can find a good used one on febay.
 
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Consider a Scangauge, it'll pull diagnostic codes if your check engine light ever comes on, and function as a tach you can plug in in 15 seconds. Google it for more info.
 
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Quote:
Consider a Scangauge, it'll pull diagnostic codes if your check engine light ever comes on, and function as a tach you can plug in in 15 seconds. Google it for more info.
How accurate is the Scangauge when it comes to MPG's?
 
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