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Gents

are there any supercharger owners out there who feel the need for a small pulley ? as I'm looking at getting some made up but need to get to an MOQ of 10 off at least
if you're not aware of this mod it adds abotu 0.1bar of more boost and the tune will usually accomodate it with no modification and you can even use the same belt typically about 15-20bhp more
 

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A highly recommended modification, judging by those who have one fitted. I have purchased one already, and now need to get it fitted before the summer properly arrives.
 

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I'll have one if you need someone to make up the numbers, still thinking long term :)

Is there any information on whether the kit is compatible with the GR86 with possible modifications? (I know airbox is different but would the rest fit)
 

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Correct - but given that it's a FA24 there might be a chance that the head mounting points are the same.
isn't the GR86 the new model thats not out yet ?
As @Kodename47 says its the same series of engine (FA) but 2.4L Ascent engine in NA form. The assumption is that the stroke remains 86mm and bore increases to compensate with the same block. Then the head mounting points will remain the same. Still too many unknowns to say for sure.

@[email protected] Also I think all the magical calculations that you had done to work out the safe torque/power limits might still be the same i.e. the rods are the same and the weak point in this new old gal :). So bolting the SC will quickly take its power to above safe thresholds, even with regular pulley..

On the smaller pulley for existing users point, will it not take away the safety margin and put the rods/engine at risk?
How much boost does the regular pulley make?
Also will need supporting mods like aftermarket Fuel Pump and Clutch as they are at their limits, i believe?

@Steeps Still too early to say yes chief!
 

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Looking forward to some more comments on the smaller pulley issue. My limited understanding was that it does take you up to the "safety limit" but not beyond. In my own case, it was not to drive on the limit for any length of time eg on track without further modifications, but a few blasts of full throttle at a time would be okay. After that, at my age of 68+, my driving skills/reactions would be exceeded anyway.

Not very scientific thoughts, but I am sure more detail will come from further discussion. If I am correct, I believe Rich196 has the smaller pulley and he does track days, so his opinion will be useful.
 

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you have it correct
when developing the kit I had the use of cylinder pressure measurement so this gave a real-time measurement of how much stress the rod and piston was under and the stock pulley was arrived at to give a healthy 10% safety margin from where the theoretical limit of the rod is
the smaller pulley bumps up the cylinder pressure to just below this limit but not beyond
to my knowledge those whom are running the smaller pulley have had no issues to date
 

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Hi guys .. i mounted and drove the SC kit from 7 month now. i may have a small issues .. is it normal than i have to refill the water of the IC time to time? From january is it happened 3/4 times already.

The cap of the water tank have a small hole and i think the water evaporate after i left the car under the sun for a lot of time. I live in italy and sometime we have more than 36° in the shade.

i think is not a leakage problem because i can drive 3000km with the same water level and then leave the car 4 days under the sun driving 80km and the level drops a lot.

Do you have the same problem? how have you fix it?

Thanks
Giulio
 

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Hi guys .. i mounted and drove the SC kit from 7 month now. i may have a small issues .. is it normal than i have to refill the water of the IC time to time? From january is it happened 3/4 times already.

The cap of the water tank have a small hole and i think the water evaporate after i left the car under the sun for a lot of time. I live in italy and sometime we have more than 36° in the shade.

i think is not a leakage problem because i can drive 3000km with the same water level and then leave the car 4 days under the sun driving 80km and the level drops a lot.

Do you have the same problem? how have you fix it?

Thanks
Giulio
Hi Giulio,
If you read the Cosworth instructions , they do say that the intercooler tank is non sealed, so there will be evaporative losses. So what you see is expected and if i remember correct, they say check every 1000 miles.

What is odd is that you mention when you leave it in the sun , it evaporates. Its worth waiting for answers to see if others have this situation but we hardly see temperatures you see on any regular basis!

Funnily i even have small evaporative losses in the main coolant tank - From full to empty of the expansion bottle in about 15K miles..
 

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uomini

ci sono proprietari di compressori là fuori che sentono il bisogno di una piccola puleggia? dato che sto cercando di truccarmi, ma ho bisogno di ottenere almeno un MOQ di 10 di sconto
se non sei a conoscenza di questa mod, aggiunge circa 0,1 bar di spinta in più e la melodia di solito lo accoglie senza modifiche e puoi persino usare la stessa cintura in genere circa 15-20 CV in più
[/CITAZIONE]
Ciao
Vi scrivo dall'Italia e da qualche mese ho installato uno degli ultimi kit Cosworth stage 2.
Sono davvero contento del risultato ma ora sento il bisogno di avere un po' più di potenza dalla mia fa20.
Ho iniziato a cercare una piccola puleggia ma non si trovano da nessuna parte.
Potreste aiutarmi a trovarne uno?

In ogni caso, grazie comunque per l'ottimo lavoro svolto e per il supporto che date ai clienti Cosworth.
 

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Hello Nico

if I have translated your post correctly you are looking for the smaller SC pulley to give more boost / power ?

sorry to say that I don't think there are any in stock, I asked on here some months ago if anyone wanted one to get up to the minimum order quantity of 10 off but there were no takers

might be worth contacting Fensport about it
 

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Discussion Starter · #1,254 ·
If you took a sample of a few rods from 100 batches of rods and measured the strength, you'll probably see a distribution of rod strength. Probably a normal distribution where you have a mean strength and a standard deviation for the maths nerds. My understand is that cintered rods have a high standard deviation from batch to batch meaning the strength is all over the place and its a bit of a lottery. This is why some lucky people have been able to run 350hp+ and others have had rods go at much less.

The design of the SC kit also will play a part in cylinder pressures. Bigger blowers have higher losses so draw more power from the engine for example, but go too small and the SC drops out of its efficiency zone because you have to spin it faster.

The guys at cosworth couldn't really tolerate even one broken engine so they made damn well sure the probability of one breaking at the cylinder pressures required for 280hp was very very low indeed.

The smaller pulley simply removes a bit of that safety meaning you have a bit higher probability of a rod going.

Ive been running mine for quite a few years though I dont drive it that much....
 

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Speaking of pulleys, has anyone played with the size of the accessory and crank pulleys? I’ve already got the smaller nose pulley and wouldn’t mind a bit more power.

I’m aware this would send it over the respective margins so would get this done at the same time as the rods etc
 
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