Sandy 0 Posted January 21, 2007 Hello Folks, I've got a 70mm pulley installed on my G60 at the moment. I'm thinking about changing it for a smaller one. Would it be worth going for a 68mm would it make much difference or is the 65mm one just too small (If I went for this size would I need to get a smaller V-belt). One more thing would I need to change anything else to accommodate the change in pulley size Engine spec at the moment AMD CHIP & PULLEY (70mm) PLUS STAGE 4 CONVERSION ON THE SUPERCHARGER VIBRATECH FRONT ENGINE MOUNT SWG TWIN G60 INLET K&N PANEL FILTER SUPER SPRINT CAT BYPASS PIPE JETEX STAINLESS STEEL EXHAUST WATER & METHONAL INJECTION BIG VALVE HEAD SUPER SPRINT MANIFOLD 4 TO 1 SCHRICK CAM PORTED & POLISHED THROTTLE BODY ADJUSTABLE FUEL PRESSURE REGULATOR (FUEL PRESSURE * 2) FRONT MOUNTED INTERCOOLER Thanks for any advice in advance Quote Share this post Link to post Share on other sites
_leon_ 0 Posted January 21, 2007 sandy what does your car put out at the moment? Quote Share this post Link to post Share on other sites
Sandy 0 Posted January 21, 2007 between 214bhp & 217bhp seems to vary between RR Days. But I've since installed a front mounted intercooler & SWG TWIN G60 Inlet so hopefully it will be higher next time. PS my Sig has the torque and stuff Quote Share this post Link to post Share on other sites
_leon_ 0 Posted January 21, 2007 am missing a few things off your list - but not 100 miles behind - might have given me an estimate - fitting BV head tomorrow. judging from others - you'll benefit from a 68mm pulley, but likely wont be night and day. would make belt sourcing easier perhaps? save and put an IHI on there ;) Quote Share this post Link to post Share on other sites
flusted 0 Posted January 21, 2007 if you go 65mm you will need red tops and remap,but IMO its well worth it. You should be able to fit a 68mm with no probs Quote Share this post Link to post Share on other sites
Sandy 0 Posted January 21, 2007 Cheers for the info Went for a 68mm got it for 49 euros (NEW) and a smaller V-belt to try and keep belt slippage to a minimum Quote Share this post Link to post Share on other sites
VEEDUBBED 0 Posted January 21, 2007 SNS.5 eeprom aswell,these chips are just the best, period. Just getting rid of that ridiculous Digi-lag transformes the car's caracter IMO. Buy 1 and you won't look back. Quote Share this post Link to post Share on other sites
Sandy 0 Posted January 21, 2007 I've got an amd chip in mine at the moment is the sns chip much better than that can't say my car suffer's from lag (never been in a g60 with one of these chips though) when ah hit the pedal goes. Quote Share this post Link to post Share on other sites
flusted 0 Posted January 22, 2007 sns will be better than amd Quote Share this post Link to post Share on other sites
morpheus20170 0 Posted January 22, 2007 So then, bigger valved head, CNC machined head or P&P head in my G60 with a FMIC at the same time, should I be able to afford it. How much is the difference? Quote Share this post Link to post Share on other sites
flusted 0 Posted January 22, 2007 get the best head you can afford Quote Share this post Link to post Share on other sites
morpheus20170 0 Posted January 22, 2007 But what is the best? Quote Share this post Link to post Share on other sites
Henny 0 Posted January 31, 2007 ask to see flow charts for each head you're considering buying... if they can't provide one, then do you really trust what they're going to do will make a definate difference... ? Personally, I'd go with a G-werks CNC head, or one from RacePower Motorsport down in Kent... ;) Quote Share this post Link to post Share on other sites
ProdigalSon 1 Posted August 2, 2007 Quick testimonial for the SNS (G-Werks) chip and a 68mm pulley: I just got these (and a charger rebuild) from G-Werks and even though I have to be sensible about bedding the charger in, I notice a huge difference already :D Even on part throttle and under 4k rpm (as the doctor ordered :( ) the car has way more grunt than before, the anti Digi-lag code gives amazing throttle response (no more 'ready, set, go' it's just 'go!') and any fast upchange in gears over 2k rpm produces that lovely "kettle's boiled" whistle from the dump valve :) I can only imagine what it will be like with an 'as new' charger after my 400 mile probationary period is up :shock: I am currently using the stock airbox, filter, charger, pipework, intercooler inlet, heads and exhaust, but it feels like a different car as far as engine response is concerned. I'll be taking it to a local tuner who will give me a couple of dyno runs for £30... I expect upwards of 185bhp and almost 190lbft torque 8) Great value for a couple of hundred quid! A 68mm pulley will get you the same boost as a 70mm pulley about 5% lower in the rev range and a redline increase in boost of the same percentage - in theory. Quote Share this post Link to post Share on other sites
junkie 0 Posted August 2, 2007 Not saying the SNS chip doesnt work as your describing but surely the increase in instant pull is more down to the 68mm pulley as it is producing more boost low down and the charger is producing the boost better been a new build. Quote Share this post Link to post Share on other sites
ProdigalSon 1 Posted August 2, 2007 It's definitely a combined effect and hard to discount the smaller pulley, but with the stock chip, even if you floored it from 3k rpm (ie. sufficient boost) there was a slight hesitation - as if it was taking a deep breath - there's no such pause at all with the SNS chip, even on part throttle and at lower revs (1500+) :D The smaller pulley just enhances the final outcome, not necessarily the speed of its onset! :evil: 8) It'd be interesting to feel/see the throttle response of the SNS chip with a stock pulley - I defo think that you'd notice it being more responsive. Anyone else with the SNS chip have the same experience? Quote Share this post Link to post Share on other sites
ProdigalSon 1 Posted August 2, 2007 PS. junkie - what chip do you have with your turbo? Have no idea what's available for those 1.8T setups :( :oops: Quote Share this post Link to post Share on other sites
junkie 0 Posted August 2, 2007 It was originally run on the standard G60 management with a Jabbasport custom chip, but now its on Haltech stand alone. You saying mine has a 1.8T/20T? Its a converted G60 to turbo, still G60 engine but with the IHIvf22 conversion 1900. Agreed would be good to see a standard charger with the sns but to get a real world comparison it would need to be on the same charger as in not rebuilt yet. Quote Share this post Link to post Share on other sites
boost monkey 0 Posted August 3, 2007 lol Junkie, excuse my bro. He is new to the way of engine conversions etc! if power / torque generation of each pulley is linearly proportional to it's diameter, we should be able to calculate what torque each pulley would give in any application, there will be an equation for it. It's science :lol: Quote Share this post Link to post Share on other sites
dirtytorque 0 Posted August 3, 2007 It will only be linear though over a certain rpm band though?! As I understand the smaller pulley just moves the power further down the rev range. However the point where the charger reaches its boost limitation will also move down the rev range,no ??!? Quote Share this post Link to post Share on other sites
ProdigalSon 1 Posted February 2, 2008 It was originally run on the standard G60 management with a Jabbasport custom chip, but now its on Haltech stand alone. You saying mine has a 1.8T/20T? Its a converted G60 to turbo, still G60 engine but with the IHIvf22 conversion 1900. Agreed would be good to see a standard charger with the sns but to get a real world comparison it would need to be on the same charger as in not rebuilt yet. Just reading back over this... Someone recently mentioned to me the possibility of having a 'twin-charged' G60 with a low pressure turbo added on, is that basically what you have junkie? Or did you remove the charger in favour of the turbo? Quote Share this post Link to post Share on other sites
junkie 0 Posted February 3, 2008 No i dumped the G-lader for the BBM/Lysholm then dumped that in favour of the IHI VF22 turbo and its running 1.5bar so hardly the low pressure turbo you suggest. If you want a twin charged set up then ideally you want a supercharger to take care of the low down torque and instant grunt with a large turbo that can be a little laggy to take care of the top end grunt, there is about 3-4 different ways you can do it though and im not fully clued up on it but 1 term used is compound charging. Quote Share this post Link to post Share on other sites
boost monkey 0 Posted February 5, 2008 ^^ true story. I still say home-engineered clutched supercharger ftw 8) Quote Share this post Link to post Share on other sites