whipple plus thump rrr

[b00stedgt]

I am using a thump rrr tensioner with a stock sized 76mm billet pulley on my whipple with a 3.5" pulley. Do you guys who have a whipple ho and aftermarket tensioner use the 76mm or 90mm?

 

[AndrewNagle]

I am using a thump rrr tensioner with a stock sized 76mm billet pulley on my whipple with a 3.5" pulley. Do you guys who have a whipple ho and aftermarket tensioner use the 76mm or 90mm?

On my 2007 I was running this pulley setup based on recommendation from Mike Malicoat at Whipple

Blower pulley 3.500
Belt Tensioner 90mm
Passenger side idler 90mm
Drivers side idler 100mm

And I had Thumprrr Pulleys on the tensioner and idlers

Andrew

 

[b00stedgt]

I will chalk that up as a $50 mistake lol

 

[Vapour Trails]

76mm

 

[b00stedgt]

no problems with too much slack in the belt? I am just trying to get anything that might be an issue out of the way before I get on the dyno

 

[Vapour Trails]

no problems with too much slack in the belt?

Absolutely not. You can run supercharger pulley sizes of 2.875" to 4.000", which is a much bigger change than 76 to 90mm on the tensioner. Anyway, the size of the pulley on the tensioner would be more an issue of belt wrap. Tension is controlled by the spring inside the ThumpRRR and the position of the sliding idler.

 

[jmn444]

I don't know... 76 vs 90 is pretty significant and it seems logical to me that the larger pulley would be pushing that tensioner down further which for most springs creates more resistance/pressure. I dont necessarily think it'd be a huge problem, but I ran all 90's with the 3.50 pulley and then ran the driver side 100 when I went to 3.25. I have a copy of Mike at whipples email saying to run the 90/90/100 from Andrew, kinda hard to discount info like that coming straight from whipple!