Thank you! 
DIY LS1 Head Porting at home can Help
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Better yet, use a shop vac and make a air wand, that's a small piece of thread attached to a straight piece of wire like welding rod or coat hanger. With the vacuum on up against the port, use the wand with the thread to find the "violent" areas vs the dead or slower areas where the thread doesn't go horizonal but lays down some. If you don't have access to a flow bench. It's not difficult make more flow but you can create problems for yourself if you take too much out of an area.
Thats a great suggestion.
I actually plan to find a spare head and then do each of the four port sets with a different port job or shaping. Then have them all flowed to see what made what kind of difference. Then once I find what it is that I am looking for, copy it to future jobs. Right now all I'm basically doing on my heads is removing the rocker stud lump and the swirl ramp and then blending everything smooth. (like that nasty limp on one side of the vavle seat). I've heard some people have reached 290 cfm @.600 with a home port job.
I actually plan to find a spare head and then do each of the four port sets with a different port job or shaping. Then have them all flowed to see what made what kind of difference. Then once I find what it is that I am looking for, copy it to future jobs. Right now all I'm basically doing on my heads is removing the rocker stud lump and the swirl ramp and then blending everything smooth. (like that nasty limp on one side of the vavle seat). I've heard some people have reached 290 cfm @.600 with a home port job.
Ohh, like the yarn and tape thing to help see your aero? Thats a good idea, I was also thinking you could use a shop vac anda small siphon tube at the intake entrance with some dyed water to see seperation and pooling or whatever... We will see, hoefully this summer its not m
y dd
y dd
hahaha you talking about by the injector at the top of the intake port?
You know I dont think that was cast into these 241's I'm currently doing. You know I've always wondered why people say that 241's were better than 853's, but the show the same flow numbers. Now that I'm porting a pair I see why. The back(or top) of the valve seat is beveled/angled into the port, the combustion chamber cast is very very smooth and the Christmas ornament is not cast into the port. These 241's are slightly better in stock form than 853's.
You know I dont think that was cast into these 241's I'm currently doing. You know I've always wondered why people say that 241's were better than 853's, but the show the same flow numbers. Now that I'm porting a pair I see why. The back(or top) of the valve seat is beveled/angled into the port, the combustion chamber cast is very very smooth and the Christmas ornament is not cast into the port. These 241's are slightly better in stock form than 853's.
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During my research, I read that it may be a good idea to leave that swirl ramp on forced induction cars to help the mix. Anybody have any feedback on that? I need to find out what any of the newer supercharged engines ports look like. If they're swirl rampless then I guess its not really very beneficial.
Everything I have read by true head porters is the ramp only promotes swirl and tumbe, to help fuel economy and mixture... any performance app would completely remove it. Race heads dont have ramps.
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Yea, when I started this and noticed every aftermarket head had removed that ramp and then even LS3 heads didnt come with it, I knew it didnt need to be there.
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Well, I finally got the truck on the dyno yesterday for the "After" dyno. After the home ported heads and a tune on my 5.3 with LS6 cam through a 4L80E.
There are a couple variables of course (always are). For one the weather was the complete opposite as it was the first time. A lot cooler. Around 55 instead of the 100+. Another is that this was with the tune adjustment. We dont know how lean it was on the first run before the heads.
Either way, the truck put down respectable numbers with a baby LS6 cam and the 80e trans. It had an increase of 47rwhp and 55 ft lb of torque. Bringing it to 329 rwhp and 334 ft lb of torque.
No longer running lean. Cool part is that this is exactly where I guestimated it to be.
Now I just need to hold back this itch for a larger cam and focus on my Turbo 92 Camaro build. I do think I could greatly benefit from a stall on this 80e though.
There are a couple variables of course (always are). For one the weather was the complete opposite as it was the first time. A lot cooler. Around 55 instead of the 100+. Another is that this was with the tune adjustment. We dont know how lean it was on the first run before the heads.
Either way, the truck put down respectable numbers with a baby LS6 cam and the 80e trans. It had an increase of 47rwhp and 55 ft lb of torque. Bringing it to 329 rwhp and 334 ft lb of torque.
No longer running lean. Cool part is that this is exactly where I guestimated it to be.
Now I just need to hold back this itch for a larger cam and focus on my Turbo 92 Camaro build. I do think I could greatly benefit from a stall on this 80e though.
Thats respectable numbre for a 5.3 through an auto with a ls6 cam. Remember that the bore is a little smaller so the rewards might not show through the same as a 5.7 or 6.0 most are using.
Fun stuff, thanks.
I have ported SB and BB Chev heads with guidance from a pro in the past.
Also ported a few Olds Quad 4 valve heads...those thing flow! I had them measured. In fact, they flowed 280 intake and 210 exh at .400 lift!
I took the easy way out and bought AFR's for my LS1, But I have the stock 853 in the garage. I should play with them some day.
Ron
I have ported SB and BB Chev heads with guidance from a pro in the past.
Also ported a few Olds Quad 4 valve heads...those thing flow! I had them measured. In fact, they flowed 280 intake and 210 exh at .400 lift!
I took the easy way out and bought AFR's for my LS1, But I have the stock 853 in the garage. I should play with them some day.
Ron
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Also, thank you for making that point. Too often would people frown and expect to see nothing but top numbers. small cam, small engine and a hp robbing 80e.
Last edited by AGearHead4Life; Feb 3, 2013 at 08:38 PM.