Anyone Upgraded Just The Drive Pulley With Sc?

[aido]

Guys, just wondered if any of you have ever just tried fitting a larger drive pulley used to rotate the pulley on the TTE supercharger - I'm talking no ECU upgrades or fuel upgrades here, just wondered what effect just that modification has?

Alos, does anyone know the size of the supercharger belt in a standard configuration as shipped from TTE? Mine was replaced a couple of months ago but is already knackered so thinking of upping the pulley size slightly in conjunction with a slightly bigger belt!

Thanks in advance

[Gord]

Guys, just wondered if any of you have ever just tried fitting a larger drive pulley used to rotate the pulley on the TTE supercharger - I'm talking no ECU upgrades or fuel upgrades here, just wondered what effect just that modification has?

Alos, does anyone know the size of the supercharger belt in a standard configuration as shipped from TTE? Mine was replaced a couple of months ago but is already knackered so thinking of upping the pulley size slightly in conjunction with a slightly bigger belt!

Thanks in advance

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Have you been talking to Steve last night he was thinking of getting some made when i had the s/c on mine to see what, if any diff it makes :D belts are not a problem as you can get allsorts of sizes from your car *****/*shop :D

[PhoneDrome]

Belt is 5PK800.

You can use contitech as they are much cheaper.

[aido]

Thanks for the info guys :)

@ Gord, yes mate, already have an uprated pulley, need to get a dyno done this week if possible and also fit a boost guage in preparation for the change to see what difference the pulley we have makes :D

[aido]

Bought a 5PK790 today as my 800 isn't tight enough even at the tightest setting!

Some generic make but will see how she performs, getting it fitted in the morning :D

As for the pulley side of things, are the comments in this thread still the current point of view:

http://www.lexusownersclub.co.uk/forum/ind...ST&f=72&t=5695&

Is there no-one out there who has ever just tested this combo, ie just the uprated pulley and SC?

Just wondering which part lowers the EGT?

Thanks in advance :)

[Dave-Ellen]

I'd agree with Mark entirely on this subject Aido.

In the crudest terms the fueling system cant cope with the increased demand (runs lean anyway as STD ).........run it at too much throttle or under load and you'll melt a piston........

Mat Wilderness did this on his mx5 turbo.........BANG

I'd tread very carefully :winky:

[aido]

Thanks mate, just wondering though which component it is that causes the EGT to be reduced?

Is it just the intercooler that causes the temperature drop? To be honest I'm still picking things up here so not sure which component out of all the bits in the upgrade causes the temp drop?

Do you have to add another fuel line or can the injectors be tinkered with?

Guess it's going to be a while before I attempt this then

[Gord]

Yes but what size of pulley are we going on about here ? how oversized is safe ?

[aido]

I don't have the pulley handy mate but think we're looking at 140mm - the standard one is 130mm and I think the Bemani one is 120mm

From the sounds of it 130 is as safe as it gets - to be honest just wanted to bang it on so we could see what boost the slightly bigger pulley produces but it doesn't sound like it's safe at all without the extra toys

I guess in theory we should see a similar sort of increase going from the 130 to the 140 as we see going from 120 to 130?

[aido]

I've been going through some old posts Gord and saw somewhere that the Bemani kit was producing 180bhp whereas the TTE is 205bhp - I am assuming the only difference was the pulley which was 10mm smaller.

I can't figure that out as if the bhp figure was directly related to the pulley size then:

130 / 120 = 1.08333333

205 / 1.08333333 = 189.23076981

The figures cannot be directly related if the 180 bhp figure is correct - I don't really understand this

If you do it the other way then:

140 / 130 = 1.07692308

205 * 1.07692308 = 220.7692314

Does anyone know if the radius of the pulley is directly proportional to the expected output, ie would that figure above be correct?

[Gord]

When Besty 1st fitted his s/c he had the small pulley on :o when he put the right one on he had lots more power :D so that must have been down to the pulley Aido, i dont see what else can change in the kit, other than the intercooler size, and i dont think the Bemani kit has a smaller intercooler than the TTE kit :D so it must be the pulley

[aido]

That's exactly what I thought mate, the only thing I can't understand is that the power loss between the TTE SC and the old version of the Bemani SC is at a different rate than the loss of size of the pulley. maybe I should so a bit more calculation to take the rolling areas into account as I guess I calculated it too simply! What i'm trying to do is work out a way of calculating expected bhp with a bigger pulley!

[aido]

Now I'm completely lost

No point taking into account the circumference of the pulleys (diameter x pi) as I still work out with the same multiplier, ie 1.08333333 as both values are multiplied by the same amount...

Does anyone know how to calculate this stuff, ie why dropping to a 120mm pulley instead of a 130mm pulley drops to 180bhp from 205bhp instead of 189bhp which seems more likely?

[TheDon]

not sure on the calculations realy, maybe comission a few sets of pullys to be made upping the diameter by +5mm each, then stck the car on a dyno etc...

on another note, it would be cool to have a way of changing the diameter of the pully whilst driving, so at higher speeds you have more hp for overtaking, and less at low speeds for more control. something similar to a scooter drive, with the weights that push further out the faster it spins.

[aido]

There's an idea for you Chris :D

I was thinking of sticking the bigger pulley on my car and getting it dyno'd to see exactly what difference it made, might even still do it quick just as a quick idea, just don't like the idea if it will blow up on the dyno :o

Maybe nitrous being shot into the manifold would do the trick

[TheDon]

well, i could always pop over to the cnc shop near me and see how mucho it would be for a couple of one offs?

just +5mm at a time (135mm - 145mm)

cant see em being cheap though

[Gord]

Now I'm completely lost

No point taking into account the circumference of the pulleys (diameter x pi) as I still work out with the same multiplier, ie 1.08333333 as both values are multiplied by the same amount...

Does anyone know how to calculate this stuff, ie why dropping to a 120mm pulley instead of a 130mm pulley drops to 180bhp from 205bhp instead of 189bhp which seems more likely?

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Aido the pulley you left with Steve, he is going to take it to a mate of his to get some made just a bit bigger mate :winky:

[TheDon]

thats cool, would have needed to take mine off, even better if someone else is doing it

[aido]

Aido the pulley you left with Steve, he is going to take it to a mate of his to get some made just a bit bigger mate  :winky:

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Cool mate :D

We have a slightly bigger one somewhere already but don't know what size it is?

Does anyone know if the standard ECU could handle bigger injectors or is that piggyback territory?

[Dave-Ellen]

Aido the pulley you left with Steve, he is going to take it to a mate of his to get some made just a bit bigger mate  :winky:

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Cool mate :D

We have a slightly bigger one somewhere already but don't know what size it is?

Does anyone know if the standard ECU could handle bigger injectors or is that piggyback territory?

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You cant get into the OEM ECU (I'm told TTE did but its ) so its off to Messrs DASTEK,HKS,Greddy etc

[PhoneDrome]

Bought a 5PK790 today...

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It won't fit! I have the same problem and also tried the 790. You won't get it over the pulleys even if you build the tensioner apart. And if you do it with force you won't get the belt off again.

The only solution was to buy the contiTech 5PK800 which is slightly thinker then the belt delivered by TTE. With contiTech you should be able to get it tighten enough.

[tdiplc]

Guys, just wondered if any of you have ever just tried fitting a larger drive pulley used to rotate the pulley on the TTE supercharger - I'm talking no ECU upgrades or fuel upgrades here, just wondered what effect just that modification has?

Alos, does anyone know the size of the supercharger belt in a standard configuration as shipped from TTE? Mine was replaced a couple of months ago but is already knackered so thinking of upping the pulley size slightly in conjunction with a slightly bigger belt!

Thanks in advance

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Not a good idea Adie. There is only just about enough fuel for the standard pulley. Even a decent exhaust manifold makes the engine run too lean.

[Tron20]

Sorry a bit off topic I know, just didn't think it was worth posting a new thread. You got your car back today aido? saw it round the back of our lexus dealer when i took mine in to be checked over and get some parts ordered. Looking like a nice motor, love the wheels, exhausts are a little big for my liking, but still was impressive to see a nicely modified IS200. Does the supercharger make much difference to the performance of the engine?

Thought I knew who's car it was the minute i saw it

Paul

[Gord]

Thought I knew who's car it was the minute i saw it

Was that coz of all the blow-up animals in the back

[Rob]

i think u can get a 790 belt on, just totally remove the tensioner, but the belt on then install the tensioner, even with the standard belt if the tensioner is on it doesnt go on too easily, with the tensioner off it just slides on.