View Poll Results: Will polishing the inside of an intake manifold improve performance?
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3
100.00%
No, it will reduce performance
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D17VTECPOWER threads consolidated - how a member should not behave
12-14-2018
#2252
Be careful installing a bigger throttle body! I have been going through hell with the way this transmission has been shifting for the last 3 months. It has been upshifting very early, lugging the engine, then downshifting aggressively and slipping into gear. It also has been locking and unlocking the torque converter randomly and very frequently going down the highway for no reason. The constant locking and unlocking was so annoying that I unplugged the lockup solenoid until I finally figured out the problem- 3 months ago, I installed a slightly bigger throttle body. The throttle body I chose was from a K20Z1, and it is 62MM instead of the stock 56MM. I have no clue why, but it made the transmission shift terribly. I reinstalled the stock throttle body, and the transmission shifts perfectly again. The only reason I can think of is because there will be more airflow through a bigger throttle body when open the same amount than the stock throttle body, so maybe that was confusing the PCM. Anyways, I just figured I'd let all of you know about the problems that a bigger throttle body caused me so you don't make the same mistake that I did. 
12-14-2018
#2253
Dr Krieger of Modification
Re: Be careful installing a bigger throttle body!
Ya the larger TB will make it seem like you're hammering the throttle all the time because a lot more air than originally needed is getting in per unit of throttle position.
Manual transmission are much easier to manage with larger TBs because your direct throttle position mechanically adjusts the transmission, rather than electronics, trying to select the right gear for far too much air.
ps: k series TB are for busters I'm rocking a J series 😉.
Manual transmission are much easier to manage with larger TBs because your direct throttle position mechanically adjusts the transmission, rather than electronics, trying to select the right gear for far too much air.
ps: k series TB are for busters I'm rocking a J series 😉.
12-14-2018
#2254
Re: Be careful installing a bigger throttle body!
Ya the larger TB will make it seem like you're hammering the throttle all the time because a lot more air than originally needed is getting in per unit of throttle position.
Manual transmission are much easier to manage with larger TBs because your direct throttle position mechanically adjusts the transmission, rather than electronics, trying to select the right gear for far too much air.
ps: k series TB are for busters I'm rocking a J series 😉.
Manual transmission are much easier to manage with larger TBs because your direct throttle position mechanically adjusts the transmission, rather than electronics, trying to select the right gear for far too much air.
ps: k series TB are for busters I'm rocking a J series 😉.
12-14-2018
#2255
Alternator vs. no alternator MPG test
I decided to do a test to see how much the alternator reduces gas mileage. Before I start, let's be clear: This test was done for educational purposes only. I do NOT plan to drive around with no alternator on a daily basis, and I do NOT suggest doing these kinds of tests yourself unless you are 100% sure about what you are doing and you understand all risks.
So now that we got that out of the way, let's begin. I started this test by driving for 30 minutes to ensure that everything was up to temp and stabilized. Then I filled up the tank with gas, got on the highway, drove 25 miles at 55 MPH with no accessories on. After 25 miles,I turned around and drove another 25 miles back to the gas station and filled the tank at the same pump for accuracy. The gas mileage averaged 27.6 MPG, which is very close to the 27.2 MPG average displayed by my Scangauge.
Here's where things get interesting: After I filled the gas tank, I unplugged the green 4 pin connector from the alternator to electrically shut it down. I did the same test on the same highway: 25 miles, turned around, and drove back to the gas station. I filled the gas tank, this time averaging 30.1 MPG. Very interesting.
The conclusion: I gained around 9% on my highway gas mileage just by unplugging the alternator connector. Driving with no alternator is clearly not practical since you would need a good deep cycle battery, and even then, you still won't get very far before it needs to be charged I could probably get 150 miles maximum with no accessories on with my Optima Yellowtop D34 battery. Also, even a good deep cycle battery will have its life significantly shortened by cycling it constantly, and replacing batteries frequently will cost much more than all the gas you'd save.But still a cool test IMO. It goes to show that there are definitely savings to be had by reducing electrical loads, like by converting to LED lighting like I did a few years ago. If I was running a lot of electrical accessories, I'm sure the gains would be even higher.
The next test that I will be doing is physically removing the serpentine belt so the alternator wouldn't be spinning. I don't expect to see any measurable gains since both the alternator and AC compressor spin freely when not under load, Still should be an interesting test though.. Stay tuned for the results.
Questions and comments are welcome as always! :smile:
So now that we got that out of the way, let's begin. I started this test by driving for 30 minutes to ensure that everything was up to temp and stabilized. Then I filled up the tank with gas, got on the highway, drove 25 miles at 55 MPH with no accessories on. After 25 miles,I turned around and drove another 25 miles back to the gas station and filled the tank at the same pump for accuracy. The gas mileage averaged 27.6 MPG, which is very close to the 27.2 MPG average displayed by my Scangauge.
Here's where things get interesting: After I filled the gas tank, I unplugged the green 4 pin connector from the alternator to electrically shut it down. I did the same test on the same highway: 25 miles, turned around, and drove back to the gas station. I filled the gas tank, this time averaging 30.1 MPG. Very interesting.
The conclusion: I gained around 9% on my highway gas mileage just by unplugging the alternator connector. Driving with no alternator is clearly not practical since you would need a good deep cycle battery, and even then, you still won't get very far before it needs to be charged I could probably get 150 miles maximum with no accessories on with my Optima Yellowtop D34 battery. Also, even a good deep cycle battery will have its life significantly shortened by cycling it constantly, and replacing batteries frequently will cost much more than all the gas you'd save.But still a cool test IMO. It goes to show that there are definitely savings to be had by reducing electrical loads, like by converting to LED lighting like I did a few years ago. If I was running a lot of electrical accessories, I'm sure the gains would be even higher.
The next test that I will be doing is physically removing the serpentine belt so the alternator wouldn't be spinning. I don't expect to see any measurable gains since both the alternator and AC compressor spin freely when not under load, Still should be an interesting test though.. Stay tuned for the results.
Questions and comments are welcome as always! :smile:
12-14-2018
#2256
Re: Torque converter question
Here is what is confusing me: If the torque converter is only, for example, 90% efficient when not locked, if you put 100 HP into it, you only get 90 HP out. The rest of the energy is wasted and turned into heat. If it's locked, it's 100% efficient, so you'd get 100 HP out, Wouldn't 100 HP to the wheels accelerate a car quicker than 90 HP to the wheels?
12-14-2018
#2257
Dr Krieger of Modification
Re: Alternator vs. no alternator MPG test
...you should have removed the belt because with the belt installed you are still burning fuel turning the mass of the belt, the alternator pulley and alternator internals.
I don't think honda alternators have clutches like ac compressors, but I could be wrong.
I don't think honda alternators have clutches like ac compressors, but I could be wrong.
12-14-2018
#2258
Re: Alternator vs. no alternator MPG test
Great point. The alternator does not have a clutch, so it spins constantly. However, the majority of the drag that the alternator causes is caused by the magnetic resistance from generating electricity. That's why turning on electrical loads drops the idle. The alternator spins freely when it's under no load. Therefore, unplugging it gets rid of the majority of the drag. If you want to see for yourself, unplug the alternator or pull the fuse with the engine running. The idle will jump up from reduced drag. I do plan to take the belt off and repeat the test when I have time, but I don't expect much difference in highway MPG. Since the test was done on the highway, the mass of the alternator internals, pulley, and belt would make very little difference since it would be at a constant speed. So the only losses from having the belt on would be from the friction of the bearings in the alternator and the belt flexing, which would probably be very small. However, if I had a way to accurately test city MPG, there could be a difference since the alternator would need to be spun up every time the car accelerated, and the alternator spins at several times higher RPM than the engine since the alternator pulley is small compared to the crank pulley.
12-14-2018
#2259
PITA Admin
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Re: Alternator vs. no alternator MPG test
I do NOT plan to drive around with no alternator on a daily basis, and I do NOT suggest doing these kinds of tests yourself unless you are 100% sure about what you are doing and you understand all risks...
...I could probably get 150 miles maximum with no accessories
...I could probably get 150 miles maximum with no accessories
12-14-2018
#2260
Re: Alternator vs. no alternator MPG test
True. I meant under ideal conditions with no accessories on, this car can go a maximum of around 150 miles total. And the last 10 or so miles or so isn't pretty to say the least. I also don't plan to run the battery down too far during testing because deep discharges take a lot of life out of batteries, even deep cycle batteries like mine.
12-14-2018
#2262
12-14-2018
#2263
If you think a good mechanic is expensive, try hiring a bad one
Re: Torque converter question
Here is what is confusing me: If the torque converter is only, for example, 90% efficient when not locked, if you put 100 HP into it, you only get 90 HP out. The rest of the energy is wasted and turned into heat. If it's locked, it's 100% efficient, so you'd get 100 HP out, Wouldn't 100 HP to the wheels accelerate a car quicker than 90 HP to the wheels?
Torque is what does the work
You could have *hypothetical engines*
100 hp with 50 ft/lb torque,
-vs.-
100 hp with 200 ft/lb torque....
Which has more power?
12-15-2018
#2266
Re: Alternator vs. no alternator MPG test
Very true. The car felt lighter and like it could roll more freely when cruising on flat ground. But I don't know if acceleration was noticeably better since I was going very easy on the throttle to maximize mileage for both tests though.
12-15-2018
#2267
If you think a good mechanic is expensive, try hiring a bad one
12-15-2018
#2268
PITA Admin
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Rep Power: 338 Re: Torque converter question
I bought an auto car recently because i had a hip replacement and still need to replace another. otherwise i would still be driving my manual trans cars.
12-15-2018
#2269
Re: Torque converter question
I think both would have the same acceleration at peak power.. The one with more torque would likely have a more usable powerband, but horsepower is a measurement of how quickly work can be done, so 100 HP is 100 HP. If I have a 10 foot long breaker bar, I could probably produce 1000 ft lbs of torque, but at a very low power. Even though I would have more torque, I couldn't accelerate the car anywhere near as quickly as the engine could, even though it makes much less torque than I could.
https://www.corvetteforum.com/forums...er-lockup.html Post 3 says "We've done a few locked/unlocked. We did a BBC with a 700R4, and a pretty high stall converter (about 3800). It gained 33 hp at the wheels locked. And it gained throughout the rpm range."
My thought is since if you dyno a car with the TCC unlocked, it will make less power at the wheels than with the TCC locked. Doesn't less power getting to the wheels mean less acceleration? Not trying to argue here since you know a lot more about this than I do and I'm sure you're right, I just want to understand this.
https://www.corvetteforum.com/forums...er-lockup.html Post 3 says "We've done a few locked/unlocked. We did a BBC with a 700R4, and a pretty high stall converter (about 3800). It gained 33 hp at the wheels locked. And it gained throughout the rpm range."
My thought is since if you dyno a car with the TCC unlocked, it will make less power at the wheels than with the TCC locked. Doesn't less power getting to the wheels mean less acceleration? Not trying to argue here since you know a lot more about this than I do and I'm sure you're right, I just want to understand this.
12-15-2018
#2274
If you think a good mechanic is expensive, try hiring a bad one
Re: Torque converter question
UNDERSTEER - is when you hit the wall with the front wing;
OVERSTEER - is when you hit the wall with the back wing;
HORSEPOWER - is how fast you hit the wall;
TORQUE - is how far you can take the wall.
Torque gets the car moving off the line. Horsepower makes it go fast.
Maybe you should step into the wayback machine
Understand what the torque converter (fluid coupling) ALLOWED first,
Note its many deficiencies
Note the many improvements to the torque converter design over the decades
A driver could stick the trans in high freekin gear and never need to shift. The car might not accelerate quick, but it was convenient.
Improvements to increase torque multiplication within the converter was greatly needed just to get the car off the line quickly.
As more gear ratios were added to fully automatic transmissions, the need for torque converter torque multiplication has kinda decreased, since wider gear ratios have kinda become more common.
On the old 2 and 3 speed trans, torque multiplication of the converter was greatly needed just to get the car off the line quickly. It allowed use of lower numeric gear ratios and still provided decent acceleration performance.
(remember, there were always physical limitations to designs due to SIZE)
Now we have far more gears and wider numeric ratio spreads are available that fit into ever smaller packages, more torque multiplication can be done inside the trans.
Now that we have 4, 5, 6, 9, and ........freekin 10 speed automatic transmissions (currently in use on some Hondas), the torque converter clutch is sometimes fully locked up as early as first gear.
Check out
Dyna Flow,
Hydramatic,
Found this, thought it was kinda cool: torque converter plus clutch plus 3 speed manual transmission
https://www.allpar.com/mopar/fluidrive.html
OVERSTEER - is when you hit the wall with the back wing;
HORSEPOWER - is how fast you hit the wall;
TORQUE - is how far you can take the wall.
Torque gets the car moving off the line. Horsepower makes it go fast.
Maybe you should step into the wayback machine
Understand what the torque converter (fluid coupling) ALLOWED first,
Note its many deficiencies
Note the many improvements to the torque converter design over the decades
A driver could stick the trans in high freekin gear and never need to shift. The car might not accelerate quick, but it was convenient.
Improvements to increase torque multiplication within the converter was greatly needed just to get the car off the line quickly.
As more gear ratios were added to fully automatic transmissions, the need for torque converter torque multiplication has kinda decreased, since wider gear ratios have kinda become more common.
On the old 2 and 3 speed trans, torque multiplication of the converter was greatly needed just to get the car off the line quickly. It allowed use of lower numeric gear ratios and still provided decent acceleration performance.
(remember, there were always physical limitations to designs due to SIZE)
Now we have far more gears and wider numeric ratio spreads are available that fit into ever smaller packages, more torque multiplication can be done inside the trans.
Now that we have 4, 5, 6, 9, and ........freekin 10 speed automatic transmissions (currently in use on some Hondas), the torque converter clutch is sometimes fully locked up as early as first gear.
Check out
Dyna Flow,
Hydramatic,
Found this, thought it was kinda cool: torque converter plus clutch plus 3 speed manual transmission
https://www.allpar.com/mopar/fluidrive.html
12-15-2018
#2276
Re: Torque converter question
UNDERSTEER - is when you hit the wall with the front wing;
OVERSTEER - is when you hit the wall with the back wing;
HORSEPOWER - is how fast you hit the wall;
TORQUE - is how far you can take the wall.
Torque gets the car moving off the line. Horsepower makes it go fast.
Maybe you should step into the wayback machine
Understand what the torque converter (fluid coupling) ALLOWED first,
Note its many deficiencies
Note the many improvements to the torque converter design over the decades
A driver could stick the trans in high freekin gear and never need to shift. The car might not accelerate quick, but it was convenient.
Improvements to increase torque multiplication within the converter was greatly needed just to get the car off the line quickly.
As more gear ratios were added to fully automatic transmissions, the need for torque converter torque multiplication has kinda decreased, since wider gear ratios have kinda become more common.
On the old 2 and 3 speed trans, torque multiplication of the converter was greatly needed just to get the car off the line quickly. It allowed use of lower numeric gear ratios and still provided decent acceleration performance.
(remember, there were always physical limitations to designs due to SIZE)
Now we have far more gears and wider numeric ratio spreads are available that fit into ever smaller packages, more torque multiplication can be done inside the trans.
Now that we have 4, 5, 6, 9, and ........freekin 10 speed automatic transmissions (currently in use on some Hondas), the torque converter clutch is sometimes fully locked up as early as first gear.
Check out
Dyna Flow,
Hydramatic,
Found this, thought it was kinda cool: torque converter plus clutch plus 3 speed manual transmission
https://www.allpar.com/mopar/fluidrive.html
OVERSTEER - is when you hit the wall with the back wing;
HORSEPOWER - is how fast you hit the wall;
TORQUE - is how far you can take the wall.
Torque gets the car moving off the line. Horsepower makes it go fast.
Maybe you should step into the wayback machine
Understand what the torque converter (fluid coupling) ALLOWED first,
Note its many deficiencies
Note the many improvements to the torque converter design over the decades
A driver could stick the trans in high freekin gear and never need to shift. The car might not accelerate quick, but it was convenient.
Improvements to increase torque multiplication within the converter was greatly needed just to get the car off the line quickly.
As more gear ratios were added to fully automatic transmissions, the need for torque converter torque multiplication has kinda decreased, since wider gear ratios have kinda become more common.
On the old 2 and 3 speed trans, torque multiplication of the converter was greatly needed just to get the car off the line quickly. It allowed use of lower numeric gear ratios and still provided decent acceleration performance.
(remember, there were always physical limitations to designs due to SIZE)
Now we have far more gears and wider numeric ratio spreads are available that fit into ever smaller packages, more torque multiplication can be done inside the trans.
Now that we have 4, 5, 6, 9, and ........freekin 10 speed automatic transmissions (currently in use on some Hondas), the torque converter clutch is sometimes fully locked up as early as first gear.
Check out
Dyna Flow,
Hydramatic,
Found this, thought it was kinda cool: torque converter plus clutch plus 3 speed manual transmission
https://www.allpar.com/mopar/fluidrive.html
12-15-2018
#2278
If you think a good mechanic is expensive, try hiring a bad one
Re: Torque converter question
The engine RPM dropped from around 6000 to about 5500, but the car started accelerating faster.
12-15-2018
#2279
Re: Torque converter question
I think it actually did start accelerating faster. But it's possible that I just think it's accelerating faster since in my mind, that's what should happen. I'll take a video and upload it. Maybe I'll time 50-70 in second gear locked vs unlocked too. That should be interesting.
12-15-2018
#2280
If you think a good mechanic is expensive, try hiring a bad one
Re: Torque converter question
6000 to about 5500
