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Has anyone heard anything about the possibility of after market cams? maybe even a regrind on our existing? anyone do any int/exh porting?
 

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You could have the stock cams reground, but that's about it. If you plan on doing any porting the exhaust side is what needs the most work on the 3.5, the ports are tiny.
 

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how much could re-grind and porting the exhaust side (and manifold to match) get you? in theory,...
 

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how much could re-grind and porting the exhaust side (and manifold to match) get you? in theory,...
Nobody has done it yet that I know of, so there's no telling. Every engine is different.
 

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improving the exhaust system (headers/port heads) on any motor will always make more power than any intake side change without tuning. so porting your exhaust ports will gain some power if portd properly.
 

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the exhaust ports on the 2.8/3.5 are small...there's a good 1/4" all the way around that could be removed...
:yeahthat:

I think from the measurements that RCSBcolo and I took of the 3.5 and 3.7 exhaust ports they're around 30% larger on the 3.7.
 

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I don't think anyone can really say for sure whether or not the 3.7 head will work on the 3.5. Honestly it'd be a waste of money IMO. The 3.7's are only going to get easier to find. I can go pick one up from a junkyard an hour from here for $1250 pretty much anytime.
 

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I know HANDGUNNER and Brewer are close to doing some Head work on the 3.5's...as soon as they find the tools it takes to remove the head.
 

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Still would be a nice 'upgrade' though. The larger valves and ports should help wake up the 3.5. Couple hundred invested compared to 1k+.
 

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Good luck getting a 3.7 head for a couple hundred. Just the bare head from GM is like $1100, and good luck finding one used for cheap. Even used 3.5 heads are few and far between.
 

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I know HANDGUNNER and Brewer are close to doing some Head work on the 3.5's...as soon as they find the tools it takes to remove the head.
Ya know my dealership told me there was a "special tool" for completing the head job on my truck... was a little weary about that but I guess this proves it. Seems expensive/rare if a DEALERSHIP only has 1 between all of their techs... and people who know my dealership will know they are LARGE.
 

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Yup. A good friend of mine is a Master Tech at a Chevy dealer up here. He was explaining it to me and what it does, although I still don't quite understand it because Motor work is mostly all greek to me!:lol:

There's actally 2 tools needed to do the job the easiest/fastest way.:econo:
 

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Yup. A good friend of mine is a Master Tech at a Chevy dealer up here. He was explaining it to me and what it does, although I still don't quite understand it because Motor work is mostly all greek to me!:lol:

There's actally 2 tools needed to do the job the easiest/fastest way.:econo:
Did he say it could be done without either present? I mean theres gotta be a way for someone to do this crap themselves should the need/want present itself.
 

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I think you need at least one, but the other one is pretty much a MUST have. From what I understand, the 1st one has to do with the cams and holding them in place or something. And the 2nd one has to do with a "tensioner" and holding it out of the way. If that doesn't get done, or it springs back in place, you have to drop the oil pan to fix it.

That's pretty much what I got out of our conversation about it but like I said, it's all a foreign language to me so I tried to relay it here as best as I could. LOL
 

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I think you need at least one, but the other one is pretty much a MUST have. From what I understand, the 1st one has to do with the cams and holding them in place or something. And the 2nd one has to do with a "tensioner" and holding it out of the way. If that doesn't get done, or it springs back in place, you have to drop the oil pan to fix it.

That's pretty much what I got out of our conversation about it but like I said, it's all a foreign language to me so I tried to relay it here as best as I could. LOL
Yeah I feel ya man... theres some complicated SHIT in there. :lol:
 

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Yeah I feel ya man... theres some complicated SHIT in there. :lol:
agreed. Just reading this thread confused me! I havent seen anyone on the other forum that has mentioned doing any head work so I'd assume it hasnt been done yet.:mc:
 

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The 2 special tools are a tool that keeps the timing chain tensioner from releasing and a tool that aligns the camshafts. You don't have to have them to pull the head, but without them you do have to remove the oil pan to pull the head to access the timing chain tensioner. You can use a straight edge to align the camshafts, that's really no big deal.
 

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Well, the tool that keeps the tensioner from releasing is a wedge with a handle that threads in. You're supposed to wedge it in to keep the tensioner from releasing and then remove the handle while you're working on the truck. It's not just for keeping the chain in place. If the tensioner releases you have to pull the timing cover to reset it, and to pull the timing cover you have to pull the oil pan.

It's kind of stupid the way they designed it. The only reason the oil pan has to come off is because the oil pump is in the timing cover and the pickup tube bolts to it, there's no way to access the bolt that holds it in without dropping the pan.
 

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I had my stock head "2.8" polished and had a machine shop regrind a OEM cam I picked up from the dealer. I tell you what,I only have the polish,reground cam and a Flomaster exhaust and it scoots! lol Not bad for a 4 cyl. Not to mention at around 3800 RPMs it's like hitting a "small" shot of nitrous.....? lol But it works.
 
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