Estimated HP from stage 2 with 2.8
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Joined: 03-20-05
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From: Rutherford, NJ
Estimated HP from stage 2 with 2.8
I don't think anyone saw my post in the Intense kit vs. the Stage 2 kit thread. So i'm going to make my own thread about it.
Alright I've been thinking. GM says the chip reflash gives it what 31hp? Now people have been getting 15 hp from a 3" pulley. So stage 2 should really give you around 251 hp going by just the stage reflash and with a 3 inch pulley dyno. Now if you were to use very simple math, every size smaller pulley would give you 5 hp. 3.35 is tock so 3.25 would give you 5 more 3.15 would give you 10 more hp etc. Using this math, with a 2.8" pulley, you should recieve at least 25 more hp. (jmc or whoever ran the 2.6 pulley recieved 43whp and still needed a better tune so that 25 is probably conservative). 25+31+205=261hp. Using this simple equation, the GM stage 2 kit should have 261hp with the 2.8 inch pulley. (or 2.85 w.e)
Remember now, these are just estimated numbers. But do you guys think that i'm pretty close or i have something going on here? Or am i just an idiot and don't know what i'm talking about?
Alright I've been thinking. GM says the chip reflash gives it what 31hp? Now people have been getting 15 hp from a 3" pulley. So stage 2 should really give you around 251 hp going by just the stage reflash and with a 3 inch pulley dyno. Now if you were to use very simple math, every size smaller pulley would give you 5 hp. 3.35 is tock so 3.25 would give you 5 more 3.15 would give you 10 more hp etc. Using this math, with a 2.8" pulley, you should recieve at least 25 more hp. (jmc or whoever ran the 2.6 pulley recieved 43whp and still needed a better tune so that 25 is probably conservative). 25+31+205=261hp. Using this simple equation, the GM stage 2 kit should have 261hp with the 2.8 inch pulley. (or 2.85 w.e)
Remember now, these are just estimated numbers. But do you guys think that i'm pretty close or i have something going on here? Or am i just an idiot and don't know what i'm talking about?
Thread Starter
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From: Rutherford, NJ
That's the thing, I have not one clue. I'm hoping it's to the wheels though. I'm just going by what they say such as the stock 205 hp even though most dyno more. They said 31 so i'm just going by that.
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From: Phx, AZ
it's GM ... while I have no proof of parts ratings I can safely say that GM has a history for under rating their vehicles and parts far under what they can actually do in some cases and many of us are driving that and other under rated products as we post
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From: Delaware
Originally Posted by AlphaJaguar5
Based on Eaton's charts and my excellent MAC1101 math skills I reached a verdict of every psi on our motor with an m62 gen 5 supercharer (the one we have).
1psi = 8.6hp
1psi = 8.6hp
haha J/K. Welcome Mang.
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From: Indianapolis
PLEASE keep this in mind, AS SOON AS you put that 2.8 on your car you just VOIDED the warranty you all claim is so important with the stage 2 GM kit. The stage 2 kit is not a 2.8, it's a 3.1 
Just a little reminder
Just a little reminder
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From: Rutherford, NJ
The moment I bought this car, I knew I wouldn't have the warranty. Besides, If I really need it, I have that magnuson or w/e act that I can read over and possibly get them with.
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Originally Posted by memphisr24
The moment I bought this car, I knew I wouldn't have the warranty. Besides, If I really need it, I have that magnuson or w/e act that I can read over and possibly get them with.
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From: Indianapolis
Originally Posted by sneaky
it's not voiding the warranty if they don't find out 
Besides, you'll wear out your SC bolt holes r&r'ing that pulley everytime you go to the dealer
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Originally Posted by FAST06SS
I take offense to that! Are you saying us technicians are idiots??
Besides, you'll wear out your SC bolt holes r&r'ing that pulley everytime you go to the dealer
Besides, you'll wear out your SC bolt holes r&r'ing that pulley everytime you go to the dealer
just repaint the bolts and buff the whole a little bit.
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From: Lexington, KY
Call me crazy, but my guess for power with stage 1 plus 2.8" pulley is 295 hp at the crank, and roughly 265 whp. I think the increased redline will allow the car to get a little more power than most expect, and GM has always underrated this car. Regardless of what the max hp turns out to be, torque and mid range power will be amazing.
^^ That is one thing I am worried about. The computer is going to be programed to work with the boost from a 3.1" pulley, not a 2.8. If your wanting to install a 2.8" pulley your going to still need a piggyback setup to be able to tune it perfectly.
