Pully query for g60 owners

[GsixT 0]

65 vs 68

1: How much more soon would one have to have a charger rebuild running a 65mm pully over a 68mm one? How much extra torque and bhp can one expect swapping a 68 for a 65? Not sure why everyone doesnt just run 65 if it gives higher boost - must be durability?

 

2: What benefit does a toothed belt kit actually give (other than sound!) ? Will it give extra power and torque at all? Are they just to cure belt slip and provide better boost higher up in the rpms?

 

3: What should one redline a g60 at with each size pullys on and can one put a rev limiter for safety on at where one needs to shift by on say a 65 or radically small pully?

 

8)

[RACK 0]

Probably take about 5000miles off of the rebuild time with a 65mm just to be safe.

Not sure about power figures though.

 

Yeah, The tooth kit eradicates belt slippage, which causes boost loss at the top end of the rev range, thus keeping the boost on. Not sure what other benefits are?

 

I don't usually take mine past 6000 with a 68mm on, not sure what people recomend with a 65mm.

Not too sure about a safety limiter either, I know the standard rev limiter on a g60 if a touch violent, and doesnt do the engine much good, due to it backing off that much.

 

Hopefully I haven't made my self look too daft with these answer, but if I'm wrong someone will put the right stuff down.

 

Cheers

[GazzaG60 0]

i run a 65mm.

 

ive heard of issues like seal wear due to heat, rebuild times etc but i am yet to have a serious problem with the 65mm. the charger is due a rebuild but its done 30k since the last on so.

 

response on the 65mm is good even from very low revs. a lighter flywheel with the 65mm should have the car up and away very well indeed from 1500rpm or so. the 8v needs boost at 8:1 to make it fly the more the better with the right tuning.

 

i change gear around the 5800rpm mark as the head is runnnig out of puff by then.

[GsixT 0]

Gazzag60 you have been running your charger with a 65 for 35,000? Or you mean your charger has not been rebuilt for 35,000 and you added the 65mm more recently?

[Henny 0]

The toothed belt conversion also boosts low down torque as well as pick up as the belt has no way to slip at all as you boot it, so gives you instant boost and response... 8)

 

It's WELL worth doing... ;) 8)

[pellzzr 0]

How much for the toothed belt conversion :?:

[Henny 0]

IIRC, they're around the £350 mark depending on which supplier/manufacturer you get it from...

[GazzaG60 0]

but if your belt doesn't slip then what benefits are there?

 

in answer to your question GsixT ive done around 15k on the 65mm. over the last few weeks its started to smoke a little when on boost so i expect a seal is gone. its done around 40k since its last build. its still making 15psi now so...

 

i like extracting power from the low revs as the engine aint no good at high revs anyway. sometiems its amazing how much that extra low down helps when taking on faster cars esp turbos.

[Henny 0]

Unless your belt and pulleys are toothed you WILL get belt slip, you just may not notice it until you get a toothed conversion on there! ;)

 

Even a standard car will get belt slip on the alternator as you turn on something BIG like the main beam or heated rear screen... it takes a few moments for the alternator to catch back up with the engine speed, and this is exactly the same with a supercharger when you drop it down a gear, or suddenly boot the throttle which is when you most want the instant-ness of the supercharger...

[potatonet 0]

I have a 65 on mine and I think I am only pulling 13 psi right now, needs a rebuild and has lots of oil in tubes. probably could dump the intercooler, but the g60 still overheats on me, dunno what it is, lovely airpockets. maybe its my head.... oh well. the 65 is nice to have gives you the ability to have a total of 3.25 more PSI than a 68 with the necessary mods, RSR, porting, tubes,..... rebuild.

[stevemac 0]

potatonet, - your cooling system should not develop any air pockets, unless your coolant level is dangerously low. Drain the cooling system & re-fill it with a mixture of G12+ & water, through the top hose. Detach the top hose from your radiator & fill the system from there. If you then develop "air pockets", I suggest you have the system pressure tested.

 

G12+ is the ONLY antifreeze that you should be using. As well as stopping internal engine corrosion, it also raises the coolant boiling point.

 

I suspect that your car may have used the wrong coolant at some time in the past, hence the sludge that you now have.

[potatonet 0]

yeah the system drains because of a leak somewhere possibly headgasket I dont know yet. that would be the reason for me getting the system pressure tested which is what I hopefully intend to do. anyone know how much a pressure test costs??? if not that ok just wondering, thanks stevemac

[16VG60 0]

The main advantage of tooothed belt drive is the guaranteed loss of belt slip, but furthermore it will also allow the belt tension to be reduced, creating less pressure upon the bearings in the alternator and waterpump therein giving longer life to these components and reduced frictional losses to bhp. Henny, who has penned a valid response to this subject himself, uses a set of my toothed pulleys and will soon anounce the bhp of his new engine install, which will have significantly benefitted from having toothed belt drive. As to cost, i offer sets of toothed belt pulleys with either 68mm or 72mm charger pulleys for £340 plus P&P. With regards to the crank toothed pulley, my system will accomodate the power steering V belt pulley directly without the need for modification to the oe inertia damper. This allows the install to be much easier avoiding further machining costs and indeed also allows oe components to be preserved and re-installed should the need arise.

[andycowuk 0]

I was all for the tooth belt system until I read this last night and it got me thinking..... the reason for the belt slip on the oe system is that it takes time to get momentum into the items being driven - primaraly the charger, if by putting a tooth belt system in place, I am eradicating slip, I am also erradicating the time taken for things to get up to speed, now this sounds good....... but at the same time raises a very big question in my head.......... What part of the charger bears the brunt of this increased force acting on it? and wont it lead to failure faster than would otherwise be experienced??

[GazzaG60 0]

i think id have to see a dyno with and without the toothed.

 

Henny has had his engine built and the charger and a FMIC and other bits and bobs too.

 

lets PROVE the gain rather than CLAIM them.

[16VG60 0]

I have been running toothed belt drive for 3 years now on the same charger coupled to both 8V and 16V G60 engines without any problems or negative aspects to the health of my charger. I know we all go looking for the "catch" these days but there isn't one with this system. The benefits are as i described previously. I have never bothered with getting a before and after dyno plot with regards to toothed belt system. The reason for this being that the facts are plain to see. The serpentine belt does allow slippage, extra tension is applied with the serpentine belt. These facts are addressed with toothed belt drive.

[scottgroovez 0]

Does the serpentine belt tensioner need to be modified seeing as one of the benefits of the toothed belt system is reduced belt tension?

[Henny 0]

nope, I'm running a normal tensioner at the moment. What you do is to replace the 2 plastic idler wheels on the tensioner arm with cambelt tensioners, this allows you to adjust the tension on the belt by turning these (as you'd tension up a cambelt!) as well as making sure that the belt runs true due to the cambelt tensioners having a lip at each side.... 8)

 

I am going to replace the normal tensioner with a fixed, adjustable length rod though as it just looks neater and will allow me to work on things that little bit easier due to not having to fight with the spring in the normal tensioner... 8)

[W3RKD 0]

very valid points here but i feel i need to add a small thread addressing the tension of the new toothed belt...

if still retaining the oe tensioner strut how can it relive tension from the components its running as this tensioner is designed to move and adjust to keep same tension on these components at all times wether ribbed or toothed belt is being used.. i feel the kits warrant the new rose joint solid strut we designed to make this kit work to its full capabilatys it is a good mod maybe not to bring more power but to harmonise and get the most of what mods you have allready done to your engine.

just my opinion.. :lol: :lol:

[beavis 0]

In relation to all those who have enquired about the toothed belt systems over the last few weeks.Details below....

 

http://www.pitstopdevelopments.com/forum/viewtopic.php?t=684

 

cheers