DIY Head Porting, polishing, valve setting..

Part 1
I was quoted MYR800 for all the above..i knew that it can be DIYed n since i got another 4agze lying around i ges its worth a try

1st step was to gather the necessities

tools of the trade

rotomatic rechargeable rotary tool set - MYR40.00
10piece mounted stone - MYR4.80
Flap wheels - MYR1.80 x 3
Wire brush, brush - MYR2.00/piece
G-Clamp - MYR14.00
Safety goggle - MYR1.80 (safety is always a priority right..)

so MYR70.00 investment for now all items can purchased at 100% superstore and your local hardware

the specific steps that i followed can be found here http://www.pirate4x4.com/tech/billavista/PDFs/Head%20Porting%20DIY%20by%20Standard%20Abrasives.pdf

since i dont have a proper flowbench or any means to measure flow before and after this process i wont try to do more than clearing the casting mark, smoothen the edge especially in the area below the valve seat..

this is the head i'll be trying to work on..its from 4agze bigport as u can see it has already been cleaned n 3 valve already been opened


the shims are cleaned and numbered so valve setting can be reduced at assembly later


intake side


big port..u can see the casting mark which need to be smoothen..i cant wait


exhaust side


according to toyota mr2 servis manual we need SST (Special Service Tools) worth MYR1xx.xx to disassemble the valve assembly..but with some creativity 8inch G-clamp and a slotted half inch tubing will do




tada!!! got the retainer, valve spring, valve seal, valve spring seat and valve out..

the valve sets are also numbered so every piece will go back to where it from later in assembly part..note that the valve spring have specific upper n lower part differentiated by 1st n 2nd coil distance..the upper/retainer part 1st n 2nd coil are closer than other coils..this act as a harmonic balancer to reduce vibration n floating at high rpms

note how ugly this head was..black and yellowish carbon deposit near the valve seat..


i know the DIY head p n p guide said to do the intake 1st but i just cant wait to try the diamond cutting tools and da#n this things can cut!! 4age uses aluminum head which is very easy to cut AND OVERcut..u have to be very gentle with these otherwise be ready to look for a new head


cleaning the seats using wire brush


i manage to almost finish a valve before the battery is dead..i think i can hear horses fleeing oredi the casting mark under the seat (left) almost vanish compared to the unwork valve (right)


to be continued again tonight, part 2, port matching

hehehehehehe... yg pro sja blh buat oo.. tlmpau port sampai nipis overheat, salah port terpaksa beli head baru...

ui...dimana ko buat?speedgarage indak jadi??patut pun ko mau apit G.....ok..continue ya...ajak la

rotomatic rechargeable rotary tool set - MYR40.00
mana ko dapat?

bod_supersperm wrote:rotomatic rechargeable rotary tool set - MYR40.00
mana ko dapat?

mau murah pg kedai 100% semua ada... x pecaya turun pg sna... chain lock RM60.00 ja ka hari 2 sya beli..

ya aku bli d 100%..best owh tu barang..pro pun mula2 buduh juga ba hehehe

Part 2
Port Matching

Port matching is a process to match the size of the gasket, intake plenum and port inlet at their contact point to eliminate ridges and bumps along the intake line and promote flow..

Gasket mock up on the head


'G' in the 4age indicates that this powerhouse utilize a performance head. From the mock up we can see only little to none material needs to be removed near the port intake..other heads may need more material to removed. Permanent marker ink is used to show where to be removed


Here we can see the injector inlet port and some casting marks which will have to be smoothen up


degreasing n decarboning..(is that even a word?)


it may look like a waste of time..but every horses counts right? really satisfied with this diamond cutting tools!! a steal for its price..


using flap wheels to do the finishing..


by then my camera battery was empty n i am to tired to continue..tonight session was cut short coz being very busy wit other things huhu will update again later..

Hi guy...when will u cont ur works man? i heard u wanna go to KL..when aa??
nice jobs bro..next time i wnt my engine repired by u...i mean, u'll teach me how its happen..which 1 must be 1st and the last..hehe..i am newbie..

going to kl tis weekend..dunno when to continue work very3 bz lately huhuhu guess this thread will have a rest for a while..u can learn how to do this here DIY Head P&P

thats why i ask u send me the head... i ask my friend to finish it...

KaRaBaU GiLA wrote:thats why i ask u send me the head... i ask my friend to finish it...

no money man =( got new project needs lotsof $$$$$ kaching!!!

yes la kan. its hard jg...