Changing Crankshaft Pulley

[AGM]

Now that I haved fitted the water to air intercooler, I can put in some more boost. To do this I need to up the size of the Crank Shaft pulley. Is there an easy way to do this. Anyone else had to change a Crank Pulley before?

Regards

AGM

[Q45tech]

Each engine is fine balanced with the crankshaft pulley as is the flywheel. Why belt tension is so critical. You will need to do some measuring on a crank strobe balancer to design a replacement pulley..............note the tiny weights in many pulleys.

[sijoko]

Aren't there any smaller pulleys available for the supercharger?

Changing the crank pulley would be expensive? It might be cheaper to upgrade to a larger blower if possible.

On a side note, I have been doing a little experimenting with regards to installing a turbo.

I bought an old set of exhaust headers and am modifying them to get a rough idea where I can put a turbo.

So far, I am leaning towards the spot where the air box sits.

Regards,

-sijoko

[elwesso]

sijoko......

You could relocate the battery to the trunk and put a turbo there........

[sijoko]

elwesso,

I don't want to hijack AGMs thread, so I will start another one.

-sijoko

[AGM]

The comments above are correct. It is not simply a case of putting on a different size crank pulley, without engineering one to correctly match the engine, modifying the alternator pulley, belt size ect.

I have already gone to the smallest pulley size possible on the Supercharger, so it is time to look at the crank shaft pulley, as there are more rpm's available with this supercharger. I will report back on the results.

Regards

AGM

[AGM]

I have finished the larger crank pulley and have put the car back together. I have bumped the boost up from 7 to 10 lbs. I would not reccommend going above 7 without an effective intercooler.

I am currently tuning the car on the Dyno. The Hp has remained the same, but the Tourqe has improved significantly.

Before the car was easy to tune on the Dyno. Now, it is jumping off the rollers to the point were I have had to strap it down to a four whell drive behind it. Even with the vehicle tied down it is breaking traction and walking sideways on the Dyno.

I am going to do as much tuning on the Dyno as possible and may have to finish it off on the track.

Tourque should also improve futher with the Level 10 Transmission due in three weeks, with the slight increase in stall speed to the billett aluminium torque Converter.

I will post the results as I go. Should be there soon!

Regards

AGM

[DAEDALUS]

AGM thanks so much for the update. I know we're all looking forward to seeing the final results. Good job!

[Eswift]

AGM, sounds awesome!

sorry for the ignorance, but what head unit are you running?

[QShip]

Continue to lead the way AGM!!!

[AGM]

Eswift,

I am running a Vortech V9G. It has the curved blades so that it is more efficient and quieter.

Regards

AGM

[Eswift]

very nice! wish i could hear it!

[1qckser]

AGM how is it all coming together? Hope to see some video soon. Maybe a huge magazine article as well.

[AGM]

1qckser,

Everything is coming together well, apart from one little niggle.

On throttle, the car is amazing, as it breaks traction on the rollers even with 275's, strapped down and weight in the car. The engine is strong and does not miss a beat.

What has got me though, is when I lift my foot totally off the gas pedal at 6000 rpm to let the engine fall back to idle, it coughs and splutters and sometimes stalls when it hits idle. The engine is great on the way up, but does not like it on the way down.

My engine Tuner thinks that I need heavier valve springs, as he thinks that the valves appear to be 'hanging' in the open position.

Does anyone know if the OEM valve springs are considered to be 'soft' or if they should be okay.

Also, what if the hydraulic lifters are the problem and not the valve springs.

Has anyone repalced the hydraulic lifters on a VH45DE with solid lifters.

As soon as I can get the engine to run smooth from max rpm to idle, the project is finished. No other bugs are present at the moment.

Members help on this one would be most appreciated.

Regards

AGM

[elwesso]

Your doing a supercharger project, right??

To me, it just sounds like its flooding.... Although, I think when you take your foot off the accelerator the injectors are shut off (I think, I vaguely remember hearing that somewhere).......

Cant tell you anything about the valve springs......

[1qckser]

Could be a problem with the MAF, when we turbocharge the SE-Rs you have to use a recirculating blow off valve, if not then you get the exact problem you are having, you can go to sr20deforum.com to search and find more info, so if your blow offvalve ( if you are using one) is just dumping into the atmosphere then that could be it, hopefuly this is the right track, good luck, and keep us posted. With the blow off valve dumping into the atmosphere its letting out metered air, the maf thinks the air going into the engine so the maf tells the ecu to supply a high amount of fuel ( rich) so if you are running your system this way you need to change it, once that metered air is sent back into the system you will be okay, hope I explained correctly

[AGM]

elwesso & 1qckser, thanks for the reply.

I am using three blow off valves, one between the intercooler and throttle body and the other two between the intercooler and Supercharger. The Motec M800 set up I am using does not use the MAF sensor.

My tuner says that I am losing cylinder pressure in about three cylinders, as it falls back to idle, hence the reason he thinks I have hanging valves, caused by what he thinks are weak valve springs.

Before I change the valve springs, what item are serviceable and which are adjustable in relation to ensuring the valves open and shut as per OEM specs. ie I dont want to change the valve spring when all that is need is an adjustment in the valve stem clearance.

Regards

AGM

[elwesso]

AGM-- Do you have the FSM??? If not, email me and Ill hook you up with the EM section via email.....

[DAEDALUS]

Nothing in the valvetrain is serviceable, except maybe bleeding the lash adjusters, which I don't think is necessary. Weak springs would be a first to my recollection.

[Chally]

AGM, I think 1qckser is on the right track. My cousin supercharged his V6 pajero, & he has idling problem & he had to make up a special vacuum switching device to let the computer know when it was at idle. It seems as if there is still too much air flow in the manifold AFTER the throttle butterfly, & even after a settling down period, he still finds it difficult to idle unless the idle contraption is working.Send us some pics & readouts from the dyno, sounds awesome!

[AGM]

Elwesso - Pardon my ignorance, but what is a FSM? If it is the 'Full Service Manual' , the answer is yes. What is an EM section.... Is it 'Electronic Manual' I have probably embarrased myself by these questions, but I would rather learn than remain ignorant. My email adress is [email protected]

Daedalus- I assume that the valve springs are fine naturally aspirated, but with 170kp boost, any valve hang, however slight may be causing my cylinder pressure drop.

A lot of boosted cars put in heavier valve springs as one of the first things they do. Is it because of valve hang? This is a new area for me.

Chally - If I am not using the MAF anymore, would there be any benefit in feeding the air from the blow of valve back into the system, rather than the atmosphere. I need to speak to my engine tuner about what inputs the M800 is using to see if losing the boost to the atmosphere is tricking the ECU.

I am a bit stumped at the moment!

Regards

AGM

[Chally]

AGM, You are probably right if you aren't using the MAF system.The Pajero has a MAP sensor setup, so I presume your computer has some sort of manifold pressure reading. With the supercharger, once you close the throttle at full song, it is still pumping all the way, even on deceleration. This may cause an unusual disturbance at closed throttle.

I'm just speculating here, but maybe it's pumping air through the idle control valve, leaning the mixture too much for a short period, so to help with that, maybe a throttle damper, like the old MAzda 323's had, may let the throttle close slower & let things settle easier.

I'm sure you'll find what's going on.

[Q451990]

... what is a FSM? If it is the 'Full Service Manual' , the answer is yes. What is an EM section.... Is it 'Electronic Manual'

FSM - Factory Service ManualEM - is the Engine Mechanical section of the manual you have.

It takes a while to get used to the abbreviations everyone uses. I remember the old thread about "What is WOT"(Wide open throttle)on the Yahoo board.

Heath

[Mayhem_J30]

Chally,Even when off throttle and the SC is still plumbing wouldn't the BOV's take care of the extra air problem?What would concern me is the loss of pressure in 3 cylinders. I would guess possible floating valves too. Increased spring rates on the valve springs would seem like something to take a stab at.

[elwesso]

You might want the Engine Mechanical section of the Factory Service Manual..... Also, if your having computer related issuues, youll want the EF/EC section......

Email me..... [email protected]

[Chally]

Quote »Even when off throttle and the SC is still plumbing wouldn't the BOV's take care of the extra air problem? What would concern me is the loss of pressure in 3 cylinders. I would guess possible floating valves too. [/quote]Mayhem, you'd think it should, but we can't say for sure, and if the valves are being held open from air pressure, there must be air getting in somewhere still...

I'd love to be there & have some meters on it.

AGM, do you have vacuum/pressure gauges hooked up both sides of the throttle? If so, give us the readings, it may help us to be a bit more accurate.Thanks

[AGM]

I will be meeting with my engine tuner next week to address this issue. I think the inputs being used on the Motec M800 are the Throttle position, engine speed and manifold pressure. The first thing I will be doing is seeing which side of the throttle body the manifold pressure sensor is.

All of the comments on the pressure difference on either side of the butterfly confusing the ECU make sense to me, as I would have expected that if I have hanging valves, surley it would result in backfiring on accelertation, not just pressure loss on decelertation. What has got me really confused is why I am losing cylinder pressure in only three cylinders on deceleration only.

I will be investigating the suggested ideas before I start changing the valve springs, only to find it is something else far simpler.

I previously set up pressure guages on both sides of the intercooler, but following the suggestion from Chally, I plan to look at what is happening on either side of the the throttle body as well.

Is there any downside to fitting heavier valve springs?

Thanks to all for the comments, it is much appreciated. I look forward to getting to the bottom of this one and finishing the car.

Pics and Dyno sheets will follow shortly, just got to get this part sorted out first.

Regards

AGM

[Chally]

Down side to heavier springs can be Cam lobe wear & Valve wear, as in pulling them through the head, & valve seat damage.

[Mayhem_J30]

AGM, what are the measured manifold pressures under decel?

Is it possible, even with your multi-BOV setup that boost is surging faster than the BOV's can relieve? I've seen that happen on turbo apps.

It would be really cool if it could be datalogged. Some exhaust gas temps, knock, timing.

[Chally]

AGM, done some investigations about your problems.

If you are using a Blow Through Positive displacement S/C, like I think you are, it will be very hard to get the engine to have a good idle after acceleration, unless you keep the idle up to about 1500rpm.My cousin tried for ages to get around the same problems you are having, & he eventually changed to a Suck through Positive displacement (after the throttle body) & fixed most of his problems including stuck open Throttles & the overheating of throttle & body.

You say you have 3 Blow off valves, now you may have the correct ones, but you need the ones from Capa in Adelaide (I think) which dump the air completely at closed throttle allowing the manifold to have normal vacuum. Because the S/C is still pumping under deceleration, there will be a build up of air pressure, when it's supposed to be a vacuum, confusing the computer completely, thus causing the engine to stall.

If you are using normal Turbo style ones, there will still be a lingering pressure in the manifold, as turbo ones blow off at a certain pressure. You NEED the capa ones that leave NO residual pressures in the manifold at closed throttle.

Hope this helps.

Chally