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2005 gmc envoy_sle_xuv
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Everyone needs to search up on his threads. He dropped his compression and ported out the head and with the cams showed a 70+ hp gain with that work done. The engine is also created vacuum from the throttle body so thats even more gain with a larger one!. Also moreso now with our engines because we probably won't drop our compression to go turbo. And then theres another 25-30 hp in the exhaust setup after you do the cams or was that with the cams? I don't remember...

The power from this will be all you will ever need to satisfy you power wise(and sound wise)

Of course you would need to take in the transmission into acct. I read somewhere it is rated for 350tqs. so someone would have to see if it can hold up to the power these cams bring us!
 

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Discussion Starter · #8 · (Edited)
two questions how much and what is the HP/Torque gains that i would get from this?
I'll try and answer your question and try to extrapolate based on my engine

When you try and improve power, you are actually improving the ability for the engine to move more air.

So (these improvements are estimates, once the first stock compression engine is done we will have hard numbers)

If you add headers and a free flow exhaust 15-25 Hp estimate. This reduces the back pressure and allow the engine to exhaust better.

Then the valve timing is the next limiting factor - this is improved by adding lift and duration on the camshafts.

With the cams done you should expect 20-40 HP on top of the exhaust gain so your up 35-65 HP - 35 for the early head and 65 for the late head.

Of course both mods will need a full fuel tune to optimize the set up.

To improve on these numbers the head needs work especially the early head.
With the exhaust port done add 20 (for the late head), 40 ( for the early head) HP after a full tune.

To give hard numbers on a stock compression engine is hard. I have not dyno'ed a stock engine then dropped the compression and tested again. Some folks say 2-10% power lost per point of compression drop. I don't have the hard answer though. At a median value 6% I dropped the compression 2 points so this is 12% lost == 35HP on a '06 engine.

My dyno testing was done using a stock exhaust manifold so with a tuned header it would have been more.

Also my cams are set up with 0 overlap - this is not idea for a naturally aspirated engine - normally you have 15-30* overlap as it really help power.

By tuning the cam overlap (using the VVT tables :) ) to match the header there is really good power to be had. Because we have dual cams we have a BIG advantage on ease of cam tuning.

To close, the guys that are racing these engines are making 100HP/cylinder - I made close to 60HP/cylinder with a really poor set up for a naturally aspirated engine.
Stock compression, bigger throttle body, headers, and cam overlap I'd add an easy 60 HP more.

These power gains are there all the time - not just when you hit boost or spray it. Right through the power band.

Think of leaving that mustang in your dust --- all with a 6 in a row to go.....
 

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Re- 4l60E

Keep in mind GM derates the torque limit so the transmission will last 150,000 miles. A Shift kit and billet 2 and 4 servo pistons will help a LOT. The band takes a lot of brunt and anything you can do to increase the clamping force will help the bands live longer.


Everyone needs to search up on his threads. He dropped his compression and ported out the head and with the cams showed a 70+ hp gain with that work done. The engine is also created vacuum from the throttle body so thats even more gain with a larger one!. Also moreso now with our engines because we probably won't drop our compression to go turbo. And then theres another 25-30 hp in the exhaust setup after you do the cams or was that with the cams? I don't remember...

The power from this will be all you will ever need to satisfy you power wise(and sound wise)

Of course you would need to take in the transmission into acct. I read somewhere it is rated for 350tqs. so someone would have to see if it can hold up to the power these cams bring us!
 

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2007 chevy trailblazer_ls
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under 2 weeks to go and 4 people....
Wrong timing or I would consider it. Missed a lot of work the past 2 months with surgery and all. In the spring we'll see if this a future mod.
 

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2009 gmc envoy_slt
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Come on guys, I know there are plenty of folks out there that are always wanting more power... really good way to get it right here. If this goes by, who's to say when itll happen again?
 

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Come on guys, I know there are plenty of folks out there that are always wanting more power... really good way to get it right here. If this goes by, who's to say when itll happen again?
:iagree:
 

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Discussion Starter · #17 · (Edited)
You certainly could - but its a lot more work to do the conversion that install the cams.


5.3 conversion would need
  • exhaust
  • engine mounts
  • transmission
  • wring harness swap
  • PCM swap
  • BCM swap/reprogram
  • plus a lot of details
 

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Discussion Starter · #18 · (Edited)
Come on guys, I know there are plenty of folks out there that are always wanting more power... really good way to get it right here. If this goes by, who's to say when itll happen again?
Unlikely that I'll spend money on this again if this group buy doesn't go. It's not free to set a group buy up on TV.


The thing that drives the price on this is the CNC programming and setup costs. This is reflected in the cost for 10 and 20. If 30 people got on-board the cost would drop even more as the setup/programming charges get spread around more.

$400 will buy (at least locally) 1 custom wheel and tire........ I know this is only part of the cost but its the enabler to get cams ground when you have more cash. If in the end you decided not to get them ground they are a salable item.
 

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2009 gmc envoy_slt
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74 Posts
Bump...

Unlikely that I'll spend money on this again if this group buy doesn't go. It's not free to set a group buy up on TV.
Hope that this doesnt pass by, just ended up getting lucky with the time that this came up for me.

If in the end you decided not to get them ground they are a salable item.
Just thought I would add some emphasis.
 

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2009 gmc envoy_slt
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74 Posts
Hey guys, whats keeping people from jumping on this? Is it the price, or the timing, or what? From all the complaining that Ive heard from people I was surprised that I didnt see a full list just a few days after the group buy was put up.

More of a bump than anything else, lol. What can I say, I want some new cams!:thumbsup:
 
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