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Undersize crankshaft pulley experience

13K views 32 replies 14 participants last post by  Cuore_Sportivo_155  
#1 ·
Hi. I just wanted to share that today I did the belt job on my TS and at this time I finally installed the undersize crankshaft pulley that was lying in my toolbox for the last two years. I got it from Singapore, it’s this one:

156 lighten crank

The pulley is visibly smaller and lighter from the original. I used shorter aux belt to keep the tension. Original belt was 6PK1842 and I used 6PK1815 so about 27mm shorter. It fitted nicely.

I did about 120 km today. The difference can be felt; however don’t expect any wow effect. Car seems pore responsive in low revs; it is easier to get it moving from standstill in first gear and it revs nicer and smoother. Above 5k rpm you can also feel the engine is “flying” any even happier to rev. At blipping the throttle at downshifts the revs react much faster.
Power steering wasn’t affected at all; at least I can’t feel it. A/C is working fine, maybe, just maybe it is not that cool when you stand in traffic jam and the car is mostly at idle. However during driving with the revs above idle no change. Today it was 31 degrees and AC power was enough for me.

In general it’s a nice mod and I am happy with it. When you change the cambelt and auxbelt the installation is just part of the job at no extra cost or work.
 
#7 ·
I am not sure. I think only problem in theory might be the idle. Because the pulley makes the accessories turn a little slower. So at 1000 rpm they turn as at 800 rpm with normal pulley, at 3k, they turn as by 2600 with normal pulley (numbers are examples, not calculation....)

So every time the engine is above idle, everything turns in the rev range as with normal pulley. I guess if I don’t idle the car for extremely long time with all electrics on, it will be fine. The manufacturer claims only extreme audio installations might be a problem. As I can’t feel a difference on PS and AC, I doubt alternator is not working well enough.
 
#8 ·
i have one of these, and have had it installed for almost 2 years now.

no issues of any kind to report relating to the pulley, or battery power etc.

to check all is well, put all electrics on, let the car idle, and check the battery voltage using alfadiag.

mine is a selespeed, and this relies heavily on full battery power.

i have used this car on a cold night, with lights, heater on full, stereo with amp&sub, no issues.

will be fine!
 
#10 ·
I think you would lighten and balance the crankshaft with the pulley installed? Or perhaps there is no need to? Speak to the engineering firm doing the lightening, they will be able to advise best.
 
#11 ·
I'm posting bike crank up to them this week and I'll ask them when they phone me (giving the all clear to do the work after inspecting journals etc). It's bound to be friggin dear since it costs £300 to remove the balancing gear and balance/ polish a 4 cyl crankshaft.
 
#12 ·
We make this pulleys without problems, it's simple lathe job, Singapure pulleys weights 850-880 grams, i go even further and lighten mine to 650gr, and 20k no problems.
By far in my opinion is the cheapest mod any TS can get.
Sadly V6 pulley have balance weight on it, and its very expensive to produce.
PS - light pulley is not recommended is you has above 400W stereo.
 
#13 ·
Hi,

I bought one of these pulleys (from Singapore) but it won’t fit the early 2.0 TS GTVs, mine is 96, the pulley is wider on the early ones and the belts have one more Vee 7 i think, newer ones have 6 i think.
Can you make pulleys for the older ones?
 
#23 ·
Hello,from here the Finland. Still all has worked well in the pulley after the exchange? Has come to any problems which would be good to mention. I thought also put the part into place when I get enough information and assurances the matter.

How do these parts can be ordered? Tell me all the possible places of purchase.
 
#24 ·
13k kms later, and all is fine. No signs of anythign unusual. Maybe but just maybe the A/C is not so strong at iddle when the car stands in traffic jam and is 30+ degrees outside, but its completely fine when driving.

I ordered it directly by email from Hotwheels singapore (link in my first post), but they delivered just to my friend in Hong Kong and he broght it to me when he visited Europe. But I am sure they post to Europe as well.
 
#27 ·
Yes, you can expect all of that and car is reving a little easier, but the difference is not dramatic and after few miles you get used to it so you dont realize it anymore. I had no negative effect in the last 1,5 years / 15k miles, price of the mod is not too high so why not. I would go for it again.
Only negative thing is that with every aux belt change you need to think about ordering different than original belt of the right (shorter) length.
 
#28 · (Edited)
At least 30k with my 156, and 10k with my Fiat Coupe 20VT and no problems.
We make for the Coupe even smaller pulley and it still can do it's job nicely....
 
#32 ·
1.9 - there will be more vibrations than new and original dual mass pulley. BTW the guy who ordered it had exact same thoughts as you.....trust me, will be disappointed......