[Zigg L1]

I know this has been brought up before. But pulley suggestions. I am doing a lower pulley would yall suggest a 9.06 or 9.45. Looking for a good reliable upgrade

[JonDaddy82]

The 9.1 pulley size is a great middle of the road upgrade. Not too big, not too small.

[SJFGTO]

The 9.1 is the way to go on the stock blower.

[Zigg L1]

I was thinking the same with the 9.1 I want to keep my car reliable and not over spin the blower too much. SJFGTO I see you have the 18% lower pulley too. Isn't the 18% 9.46? Vengeance Racing suggests the larger of the two. I plan on buying that from them with a remote tune after I install this winter

[SJFGTO]

Originally Posted by Zigg L1

I was thinking the same with the 9.1 I want to keep my car reliable and not over spin the blower too much. SJFGTO I see you have the 18% lower pulley too. Isn't the 18% 9.46? Vengeance Racing suggests the larger of the two. I plan on buying that from them with a remote tune after I install this winter

It is a 9.17 inch diameter.

[Zigg L1]

That is what I wanted the first time vengeance Racing was pushing the larger pulley. I will ask them for the 9.17 thanks fellas

[PROMETHEUS]

What kind of HP increase are we talking with the 9.1. I was looking at doing something to add some HP, without taxing the cooling system.

Did big upgrades on the C7 Corvette and regretted it! Could never keep it on the track any longer than 10-15 minutes w/o it going into limp mode.

[Zigg L1]

I don't track my car just because there is nothing really close to me. I just want to add some more HP but not get heat soaked too much. And keep it reliable. From what I've heard around here and other sites that anything over 18% overdrive would require cooling and fuel upgrades to optimize. Obviously adding cooling upgrades would help anyone.

[Markoz28]

I have the 9.1 lower and That’s as far as I would spin this SC. For track use it might produce too much heat without upgrading some cooling items. Maybe consider a smaller pulley.

I think the 9.1 is considered a 15% on the 6th gen and an 18% on the 5th gens

[Zigg L1]

Unfortunately vengeance Racing only carries the DSX pulleys and they only have 9.06in 13% or 9.46in18%. VS lingenfelter with the 9.17in I doubt it will make that much of a difference between .11in

[Markoz28]

Originally Posted by Zigg L1

Unfortunately vengeance Racing only carries the DSX pulleys and they only have 9.06in 13% or 9.46in18%. VS lingenfelter with the 9.17in I doubt it will make that much of a difference between .11in

Yea in that case I would go with the 9.06 for sure. It’ll make some power. I’m guessing about 30 whp.

[Can'tHave2MuchHP]

Vengeance carries Lingenfelter pulley rings/ATI Balancers in addition to DSX and the really nice Innovators West one piece billet lower pulley/balancers (Might be Z06 only). Pick whatever size you want, they will do it. https://vengeanceracing.net/2017-cam...balancers.html

As said above, 9.17 is the way to go. 9.17 is considered 15% on the LT4. It was 18% on the LSA. Anything past 9.17 will require Meth at a minimum. Truth be told, even 15% is going to get really warm depending on the climate and your usage. I would have a few small cooling things done like thermal reduction plates, t-stat, and also get the blower ported by Kong/Jokerz/Fasterproms etc. while you're at it.

That said, Vengeance has built dozens and dozens of bolt on LT4s so they have plenty of experience. Dave and Ron have always taken good care of me and people I know.

[Zigg L1]

Dave from Vengeance Racing has still recommend 9.45in
just got off the phone with him. I did mention not wanting to work the blower too hard. The 9.45 was still his recommend pulley. He said if it were his he would do the 9.45in. They don't carry the lingenfelter pulley anymore it would be the DSX either 9.06 or 9.45. That's my options. I did also get a thermostat and already have cooler plugs.

[Can'tHave2MuchHP]

Originally Posted by Zigg L1

Dave from Vengeance Racing has still recommend 9.45in
just got off the phone with him. I did mention not wanting to work the blower too hard. The 9.45 was still his recommend pulley. He said if it were his he would do the 9.45in. They don't carry the lingenfelter pulley anymore it would be the DSX either 9.06 or 9.45. That's my options. I did also get a thermostat and already have cooler plugs.

Hmm, that's interesting. I talked with Dave about doing a bolt on C7 Z06 a year ago, he was in the 15% or 18% boat. Meanwhile all the feedback on Corvette Forum was recommending sticking with a 5%-10% pulley unless I was adding Meth. Dave was adamant that up to 18% was fine on pump only. The tuners I spoke with were adamant that an 18% would pull all sorts of timing after the first hit. My guess is somewhere in the middle lies the truth but who knows without trying it back to back.