Need more Torque~

[wkthyk]

Hi everyone,what modifications do you guys think are good to increase torque at low rev for T2?

[kartracer]

a bigger dump pipe and exhaust will give good torque increases. although at low revs im not sure. you will get less turbo lag, but the gains from bigger exhaust might be more noticable higher in the rev range.

a boost increase will give u more torque aswell. if low revs is your concern maybe look at an electronic boost controller (like bigelboe's?) this will reduce turbo lag and get u onto boost faster.

hope this helps

[trustpower]

more stroke = more torque

that could be a worthwhile project!

other than that, theres not a lot you can do with such a small capacity not to mention turbo'd engine.

[James]

Oh god no dont stroke a city engine, its a bloody tractor engine already  :o.

But yeah, get yourself some form of boost controller it makes a HUGE difference to low down pull, also a dump will let you build boost quite a bit earlier.

My boost controller holds the wastegate shut until it reaches about 8 psi (adjustable) and it does that in any gear by about 2500. All gears bar 1st are in the boost by 2000 rpm.

But be prepared for a lot of wheelspin, If I go from a standstill with no boost controller I just got, might squeak the wheels a bit in 1st. If I go from a standstill with my boot controller I spin it up all the way to the redline in 1st and then some in second, and thats on reasonably sticky 205/50's so if you have 185's be prepared for some 3rd gear fun ;D

PS trustpower: There is a whole lot more you can do to increase low down torque especially because it is a turbo engine and because of its very very long stroke already. Some other mods that could increase low down torque would be:

Shave the head for more compression, huge difference
New intake manifold with velocity stacks
Equal length exhaust manifold
CO2 injection in the turbo  :P
Better air cleaner assembly.
Modify cylinder head and piston crown shape to promote faster combustion and more quench
Improve short side radius in head, as well as cleaning up all the casting dags especially in exhaust to keep velocity up.
PUT A SHORTER FINAL DRIVE IN IT, citys are beggin for this
Get teflon coated pistons with total seal gapless piston rings, or either of the above.
Better fuel so you can run a bit more advance possibly

And thats about all I can think of off the top of my head ;D

[wkthyk]

Thanks a lot bigelboe with plenty of ideas. Boost controller is up my mind too, I think I will get the HKS EVC and install it next time when I go to dyno and re-tune the car. I was told that the car gets a 2.5" dump pipe already, but I can't really feel the car boost up quicker... may be I still put a factory airbox there with old dusty air filter

Originally I want to mod my Pod filter from S13 into City, but I can't find a suitable "cool" place to put the filter as the car get air conditioner. Do you have any good suggestion to put the filter?

Moreover I think there is a little plastic duct from top of engine cover to airbox (the return route for heated engine oil gas), should I just dump that pipe to ground (environmentally unfriendly) or pass through an oil catch tank?

And here is a final question... about the spark plug. What kind of spark plug is using in T2? standard ISO or JIS spark plugs? I want to put Iridium plugs but just lazy to pull on plug out from engine and measure... ;D

[kartracer]

According to the honda city infobase use NGK BR6EB-L-11, personally I wouldnt go with Iridium I think its a waste of money.

We are putting our Pod filter where the battery was, and moving the battery into the boot. We have a hole in our front bumper where the drivers side fog light was, and were putting some ducting straight up from there to around the Pod to get cold air, no cold air box required.

There are some good pictures in the gallery of how people have installed pod filters, check that out.

[wkthyk]

But when I put the Iridium plugs into my skyline, the changes are significant. the rev comes up a lot quicker, and the torque comes stronger.

[James]

That was probably because it needed new sparkplugs in the first place.

I have a mate with a turbo rover that swears by iridium, I dunno tho, why don't you buy them and try them out and tell us if they are any better.

Just go to a place with plugs and say I need the iridium equivalent of BR6EBL-ll's.

Yeah with your cold air intake, most people remove the AC compressor and run a pod filter there, possibly with some ducting from the bumper  to scoop some nice cold air.

Factory air-box prolly is strangling it a little bit, I have a 4" pipe running from my pod to the turbo :p

[turbocab]

my original plan was to use the duct that the stock intercooler uses with a fiberglass bit going from there to where the battery used to live with a pod filter,but ime going to stick with the unifilter panel that is in the standard airbox at the moment to avoid defects from those nasty police
my new t2 runs cold air to the stock airbox from the back of the left fog light thru the guard and in thru the hole where the airbox's oval duct sits against

[James]

Colza recommends a new turbo, he said it made a huge difference, even tho his turbo didnt have much shaft play to begin with.

[wkthyk]

my T2 got Td04-B11 turbo with external wastegate already~ it was bought from Glenn and quite a lot of mods already on it... such as 2.5" dump pipe and exhaust, HKS Fcon, etc. However just feeling something wrong that the car with relatively low torque, even worse than my NA City... I assume there is something wrong with tuning. I think I need time to fix them out.

Tonight I just shifted the set of earthwire to the T2 from the skyline, and also I found a high energy ignition amplifier on this little T2 so I connected it back to the coil. These two things seems giving me back quite a bit of torque, also the hunting of rev is gone too. I really need time to trace back all the wires in the engine bay and find out what they are... so many unconnected wires.

[James]

Yeah you wont get any pull low down with a big turbo like that on, the reason your NA city feels torquier is because it is, the only reason the turbo city is torquey as farked low down down is because it has a tiny turbo that starts to spool at 1000rpm.

Now the NA city has a compression ratio of 10:1 so to equal that with the city turbo you need to be running like a little under 0.5bar of boost so watch your boost guage in your turbo city, you prolly only get to that level of boost upwards of 2500rpm.

Try and find out whether your car has had the compression boosted, that will give you some more torque.

[kartracer]

yeah the td-04 sounds like the reason you dont have much torque low down, unless your compression has been raised, you have 7.6:1 (which is pretty low) untill whenever the turbo starts to boost.

how do u find the td-04 once it is higher in the revs? what sort of boost do you run with it?

[mequetrefe]

put high performance camshafts, but when you do that, make sure to change the cam pulleys, put bigger valves which means the valve holes must be worked on.  Man why don't you just put a CNG fuel system and you will fly all the time.

[wkthyk]

ya the TD04  is possibly the reason. I can feel the torque is coming out after 4000rpm... and the boost just quickly to about 1.1 to 1.2 bar at about 5000rpm. I tried that the car doesn't overboost until 1.4 bar at 5500rpm (the boost controller is detached and haven't got a new one yet).
The car goes quite good and a bit of spin after 4000rpm, but just only 0 - 3500 rpm... the car goes like snail. Now I connected the high energy ignition coil amplifier, seems better because the car revs faster... but still slow at low rev. The car is even slower than an Echo until the torque comes, but cars beside me just gone far away already... so I need torque at the low rev to improve the drivebility when hanging around in CBD.