MawneeC5

iTrader: (12)

I'm about to join the ranks of the DIY Head porters
I snagged a pair of 5.3 heads off ebay for $125 and have all the tools and supplies on the way to port/polish them. I've found a few really detailed walkthroughs that have given me an idea of the do and donts. I'd like to go a little farther than just removing casting remnants though. I'm planning on port matching JUST the top of the intake and exhaust runners since from what I understand the lip can reduce backflow, but I"m open to advice

I figured I'd ask you guys that have done it about your experiences with this project.

Anyone here destroy a set of heads doing this? if so what did you do wrong?

What kind of results have you guys gotten?

IS there a sure fire way to maximize midlift flow verses high lift? I've got a cam with 575 lift...so I could care less if they flow 500cfm@.600

Thanks in advance for any advice

I'd really like to have them flow tested before and after...but unfortunately the tuners and machine shops around here are premadonas that believe they crap gold and want rediculous amounts of money just to look up from thier magazine at you.

Crazy Man

iTrader: (6)

Id be intrested in the same info....

Order 66

Head porting is a science. Not for the DIY. All head porters had lots of pratice to get get a good flowing head. If you never did it before you can make the head flow worse then it was in stock form. Port matching is really not the area for gains. For the price of the new 243 stage 2 heads for a little over $800 why would any one want o do it them selves. But if you d really want to do it you need to have a flow bench handy and start slowly. Take off a little at a time and flow it. If you can get a flowed then you can really do harm to them. Good luck though.

Wnts2Go10O

iTrader: (12)

ppl like to try things themselves because the either A) enjoy it and/or B)to save money. porting is more talent than science when done by hand i say get a trash set of iron heads to practice on first. also if u can find some trash aluminum ones thtll hel u even more.

Order 66

I agree with you on just wanting to do it. But you will need a couple of heads to play with just to get it right. Thats alot of hours. Unless you have free time and enjoy it, i say go for it. Just dont be disapointed if they dont come out right.

MawneeC5

iTrader: (12)

Just to clarify a few things.

1) The heads are on the way, it IS going to happen. So the point of good or bad idea is moot. Keep in mind, I paid $125 for these heads.....at that price..they might as well be 'junk' heads. I dont really have much to lose in this situation.

2) I've done a great deal of research! There are simple porting tricks that will increase flow garanteed, removing casting lines and such... Just doing that and bolting on the higher compression heads will be an improvement over my stock heads.

3) I do machine work at my job ALL DAY, every day for the last 10 years. I can weld, grind and fabricate metal very well. So I know my way around the tools I"ll be using. I"m not some guy picking up a grinder for the first time and trying to poke some breather holes in some heads.

4) Most Improtantly I AM doing this just for the sake of a car project. I'm bored out of my mind and spending a couple of weeks spare time leaning over a set of heads for my vette will be rewarding regardless of the outcome. Even if I trash the heads...the knowledge gained will be worth the effort.

hals73rs

iTrader: (4)

Intake.......... I generally take out about .050 on each intake runner wall where it meets the intake and down into the runner. Remove the rocker bolt boss and intake swirl. Narrow the valve guide and smooth all casting flash and casting lines. Blend everything together and be conservative not to remove too much material. Since you are a machinest this next step should be easy. Take an old intake valve and have it cut down to 1.80 diameter. Open up the valve seat/bowl area until this 1.80 valve fits down inside the seat. Again blend it all together. I usually finish with 80 grit.

The exhaust is alot easier and takes a lot less time. Do the same on the valve seat/bowl area but with an old exhaust valve that has been cut to 1.40 diameter. Narrow the guide and again, remove all casting flash and casting lines. People make the mistake of opening up the exhaust port to match the header......... Don't do that. Just remove enough material as needed to remove casting lines/flashing. I usually finish with 120 grit and polish with fine scotchbrite flapper.

The combustion chamber just needs smoothed to remove any burrs and can be polished as you want.

The most difficult job of porting is to be consistent and having patience. Doing the above you should have a head capable of 285 intake and 225 exhaust with excellent low-mid lift flow. Getting a good VJ is also a must. Good luck.

Bo White

iTrader: (59)

Look under my screen name and check my other posts. I have went over this in pretty good detail so its there to be had. I will search as well and put links in this thread.

Bo White

iTrader: (59)

This will do at the moment...still searchin:
www.ls1tech.com/forums/showthread.php?t=316041
www.ls1tech.com/forums/showthread.php?t=414121

2xLS1

iTrader: (25)

Are you aware that 5.3 heads have smaller intake valve than your stock LS1 heads. 1.89" vs 2.00". Everyone using 5.3 heads puts bigger valves in them.

hals73rs

iTrader: (4)

Good catch..... I didn't notice that. You would definetly want to use LS1 intake valves. Be sure to unshroud the valves too.

MawneeC5

iTrader: (12)

Thank you Hal and Bo, Great info !!

MawneeC5

iTrader: (12)

Yea, I had already planned on swapping over the valves from my LS1 takeoffs, that will allow me to use the valves that come on the 5.3s for all the dirty work

GuitsBoy

iTrader: (4)

Dont listen to the nay sayers. I am currently porting my own heads, and so far im pretty happy with the results. Theres a good ammount of info on the boards, unfortunately with the search broken, its hard to find. Ill post a few links ive got saved:

https://ls1tech.com/forums/showthrea...Y+ported+heads
https://ls1tech.com/forums/showthrea...Y+ported+heads
https://ls1tech.com/forums/showthrea...Y+ported+heads
https://ls1tech.com/forums/showthrea...Y+ported+heads

Heres my first time out (still in progress)
http://www.ihearyou.com/~tony/camaro...ds/page_01.htm
http://www.ihearyou.com/~tony/camaro...ds/page_02.htm

MawneeC5

iTrader: (12)

Thanks for the links
I saw your thread a couple of days back, nice work on those heads

With all this great info you guys have given me..I"m itching to get started! The heads are to arrive today, but most of my supplies wont be here until next week

GuitsBoy

iTrader: (4)

I highly suggest looking at mcmaster carr for supplies. Inexpensive, plus real quick shipping. Id also suggest an air grinder, although id like to try the electric grinder with an external speed control like HF sells.

MawneeC5

iTrader: (12)

I'd prefer to use air, but I have to hold off on a good compressor until my new house is finished. I"ll be using an electric dremel style tool with adjustable speed. Though I think I may wire up my own voltage controller for a little more control

GuitsBoy

iTrader: (4)

1/8 or 1/4 collets? If youre trying this out with a regular 1/8" sized dremel, youre in for an awful lot of work. I think either rotozip or craftsman has a 1/4 electric tool with a flex shaft that would probably do well. The dremel, while it can be used in certain areas, is simply too anemic to do any of the serious hogging out.

MawneeC5

iTrader: (12)

1/4 collet Infact I had bought an actual dremel(1/8) and returned it for just that reason I grabbed a Nikota with a flex shaft off ebay for $20 shipped.

http://cgi.ebay.com/ws/eBayISAPI.dll...MEWN%3AIT&rd=1


**BTW what kind of guitar do you play ? I have an ESP limited reverse myself

xfactor_pitbulls

iTrader: (16)

FYI for the DIY, dont expect to have near the results you see on the message boards. You can do some cleanup and make things alittle better, but can also ruin a set fairly easily. There is so much to do with valve and seat angles that you cant just know. I have blown through and cut up heads, just to learn the limits of what can and cant be done, spent over $1K on flow bench time, and am just now getting to the point that I can compete with most of the CNC head companies on here. The only reason I am where I am, we have a very knowledgable guy locally that has taken me under his wing. Otherwise I would still be stuck in the mediocre range. Just food for thought. Its something to do as a hobby, but you have to invest tons of time and money if you EVER plan to get good at it.

Brandon