Porting my heads (first time)

SuperCoupeSC91

Registered User
well as some of u knew from another post i did, my red SC, newest one i just got, the headgasket went, now i stole my exhaust from my blue car, (high flow downpipes SCP + 2.5 to 3" to 2.5 SCP also) now i'm getting a set of exhaust manifolds ported from tbird 88, now i had a set of extra heads from my bro that he gave me, so i just had them pressure tested and plained, there fine, and i just gutted one took out all the valves, now i started to port the exhaust ports on 1 head, now i want to leave the stock cam and stock valves, but have a little more power, maybe put in a 10 % pulley, i think i remember once reading that not to touch the intake ports on the heads, just port the exhaust side is this true ? i've opened the exhaust ports alot, just wondering if it would make sense to open up the intake ports as well a little or not ? also my bro told me to get some compound and put the valve in the whole and spin them (i guess a way of cleaning them) is this the correct and only way to do this ? whats that stuff called ? well i took some pics last night (below), i worked on them for a few hours already, and went threw a few dremel bits, also whats the best way to smooth out the ports so there not grooved ? machine shop ? here are some pics i got yesterday, i got new valve springs + valve seals for these heads, can i clean up the stem of the valve with a dremel wire brush or should i not touch them ? they have a little build up of black on them ? Thanks Alex L
 
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SuperCoupeSC91 said:
well as some of u knew from another post i did, my red SC, newest one i just got, the headgasket went, now i stole my exhaust from my blue car, (high flow downpipes SCP + 2.5 to 3" to 2.5 SCP also) now i'm getting a set of exhaust manifolds ported from tbird 88, now i had a set of extra heads from my bro that he gave me, so i just had them pressure tested and plained, there fine, and i just gutted one took out all the valves, now i started to port the exhaust ports on 1 head, now i want to leave the stock cam and stock valves, but have a little more power, maybe put in a 10 % pulley, i think i remember once reading that not to touch the intake ports on the heads, just port the exhaust side is this true ? i've opened the exhaust ports alot, just wondering if i'd make sense to open up the intake ports as well a little or not ? also my bro told me to get some compound and put the valve in the whole and spin them (i guess a way of cleaning them) is this the correct and only way to do this ? whats that stuff called ? well i took some pics last night (below), i worked on them for a few hours already, and went threw a few dremel bits, also whats the best way to smooth out the ports so there not grooved ? machine shop ? here are some pics i got yesterday, i got new valve springs + valve seals for these heads, can i clean up the stem of the valve with a dremel wire brush or should i not touch them ? they have a little build up of black on them ? Thanks Alex L
Well, you have it backwards. You are supposed to leave the exhaust ports alone and open up the intake side. The only time you should mess with the exhaust ports is if you are going to weld them and reshape them. You need to at least gasket match the intake side and then match the ports on your intake to the intake ports on your heads. You would be better off getting a cam with no headwork than doing headwork with no cam, although it is better to do both, obviously. If you opened up the exhaust ports at all then you have probably ruined the heads. The compound you are asking about is called lapping compound. You use it to clean up the valves and valve seats. Did you mark the valves before you tooke them out? That is always a good idea, unless you are going to have a machine shop do a valve job for you.
 
i kept the outside diameter the same on the exhaust side, i just ported the insides of them, u gotta be kidding me to say not to open the exhaust side ? why wouldnt u, it will just exhail better ? it should lower the backpressure with ported manifolds.. and yes my bro made sure i labeled each valve for each head. so i should open up the inside of the intake ports as well then ? Alex L
 
SuperCoupeSC91 said:
i kept the outside diameter the same on the exhaust side, i just ported the insides of them, u gotta be kidding me to say not to open the exhaust side ? why wouldnt u, it will just exhail better ? it should lower the backpressure with ported manifolds.. and yes my bro made sure i labeled each valve for each head. so i should open up the inside of the intake ports as well then ? Alex L
Well, you want the exhaust gasses to have a certain velocity when leaving the combustion chamber. If you just open up the exhaust it will change that characteristic. If you just smoothed out the bowls and left the port opening alone you should be OK. I though you had ported the opening as well. You can buy porting kits off of ebay that will come with sanding drums of different grits, shapes and sizes. That's what you will need to polish your ports. Definitely, at least, gasket match your intake ports on your heads though.
 
i just opened it up on the inside, the outside diameter shape is stock, now on the intake, i wanst going to largen the outside shape, i wasnt going to largen it, i was just going to open the inside after the shape is that ok ? or should i make the shape holes bigger and match the gasket ? thanks Alex L
 
what you want to do is put your intake gasket on your cylinder head. Trace around the intakes with a blue pen using the gasket as a template. Port your heads to the lines that you traced.
 
i will also have to port my intake manifold, ports as well ?? the thing also i'm trying to do is, my car is still together, when we rip it apart i have to put it back together, and hopefully the same day, so i'm trying to do what i can the most with what i have, so theres no time that my bro is waiting for me, i got another set of used manifolds from Victor at Spinningwheels-sc.com (thanks to him + Diane) and he sent them to t-bird 88, and i'm getting them back so i wont have to wait to do the manifolds. so if u say thats all i got to do is that to the head please respond asap :) then i'll do it right away, if i need to do the intake, i might have to get my bros (to the SC thats 75% back together, and give him mine when i rip mine apart) and modifiy his, thanks for the help.. Alex LaChance
 
my bro has a spare intake manifold, i put up the gasket, i see what u mean, i will port them both, the intake monifold and the heads on the intake ports , thanks for the info.. Alex L
 
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Darkside is right....you cant just port away on the exhaust side. Even if you didn't change the size of the opening....the more material you removed in that bowl area will effect flow. If you take a look at welded heads, the floor is cut low, and the bowl is actually small. This keeps the velocity up and aids in any exhaust flow.
 
here are some more pics, i didnt do the intake ports on the head yet, i just did my intake manifold, freakin takes a while, also how much more better would it be to open up my intake manifold and mill out that divider like it says at the mn12performance.com website, i'm debating if i should do it or not, just i'd have to pay a machine shop to weld it shut after, i can get it milled out at my work. any other suggestions/tips would be nice.. Thanks Alex L :)

** the pic when i was holding the gasket was a hair off, thats why u see some metal, it matches perfect, that pic makes it look off...
 
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not to get off topic, but im just wonderin what your mom thought of the new car ? and hows everything goin with it
 
hey, she likes it, we havent done anything yet, my bro has to do my head gaskets first, my cousins cav, then my moms.. so it might be maybe a month :) becuase he works and is very busy and doing stuff to his landscaping.. Alex L
 
just as i was done my intake and was finishing up my heads, i went threw the wall on the exhaust ports on my heads on 2 chambers :( , i do have the worst luck.. dammit, that sucks now. i have to get it re-welded and do more rounding off.. i'll take pics when done..felt like i had to vent sorry :D all of this better be worth it in the end..Alex L
 
i called one machine shop and the guy said he thinks they'll have to bake it first then weld it ? this true ? he wasnt to sure but said i might have to heat it up before i get it welded ? to me thats news.. Alex L
 
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