where do the you guys get your heads ported? im looking for a place in the midwest that does a good job and can flow bench the ports. anybody know of a good place?
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head porting?
- Thread starter bowtiebuba
- Start date
Most don't. It is a street head, not a race head, but the factory 7M will make plenty of power stock.
If you are trying to get as much as you can, then have it.
Read Defiant 7M's thread. He is naturally aspirated, so he is doing internal mods.
If you are trying to get as much as you can, then have it.
Read Defiant 7M's thread. He is naturally aspirated, so he is doing internal mods.
Malloynx put down 543 with the stock head and manifolds. How much higher are you wanting to go on the street?
true but since most people tear down and rebuild the whole engine why not have it done it only adds a few hundred dollars and a good flowing head and intake manifold makes making power easier, I am going to have it done when I rebuild my engine, if you build it solid and flows well you can make more power for less in boost or mods. Theres a machine shop in nashville I've heard good things from antman on here about and his buddy ken, they are outta jackson TN and they took the stuff to nashville for machining. Theres some places in Illinois and missouri to, you'll have to do some searching but let me know how it works as I plan to do it.
Nick M said:
im going for 700 rite now and more in the future my short block is built for it i gota have a head up to the task.
you are doing this build part by part i assume? dont know how old you are or you backround so i want make false acusations but i do hope you relize 700hp is ALOT of power to handle i would deffently recommend that a car with that much hp be track only or driven on the street on a rare occation its not easy to drive a car with that much hp around the city in traffic and the like.bowtiebuba said:
whenmunkysfly said:
Have you ever driven 700 to the wheels? In a car as heavy as ours it is definately streetable.
As far as a place to send the head to be ported in the midwest, call up SP or some shop near you and ask where they sublet their machine work. I would just send it to SP and have them take care of it, if you arent going to do it yourself.
Adjuster
Supramania Contributor
I did mine, it was not that hard, but I'm pretty mechanically minded.
Larger valves are a must. (Mine are 1mm over size compared to stock.)
There have been a few who have used 2JZ valves which are 1.5mm OS, but are .05mm longer than stock, so they have to be cut down to work right. (There is a line of thought to have your cams re-ground to a smaller base circle and use the extra left over to increase lift and duration, but I have not yet seen it done.)
Whatever you do, replace your valve springs. Comp Cams sells "Inner Valve Springs for a Big Block Chevy" that are a tight fit in the 7MGTE head. (They work great, have higher seat and installed pressure, and better coil bind so you can run higher lift cams in the future if you want with no problems there.) Best part is these springs are like 70.00 for 24 of them.
I spent most of my time porting out the exhaust side. You want to leave a 1mm lip between the gasket size, and the port size. This is an anti reversion dam, and really helps on the log manifolds to keep your tourqe numbers high. (I did mine with 1mm lips, and Dr. Jonez removed his, and the tourqe numbers were better on my car, but his top end flow numbers are better, so everything is a trade off.)
If your going to run a tubular manifold, and it's built right, I'm not sure you need the lip so much.
I built my motor with a log type manifold in mind, but now that I'm changing over to the tube one, I've found just playing with compressed air, that the Ebay tubular one actually creates a pretty good venturi effect, and it draws air down the other tubes when you blow air into the tubes next to it... This scavange effect would make the tourqe numbers better at low to medium RPM, and since the runners are larger than stock allow for optimum top end power as well.
One tip is to use an old valve, or valves to protect your head when porting the chambers. You want so very carefully smooth all sharp edges, and remove the material with sharp edges around where they cut the valve seats. (Blending the bowl is what I've heard it called.)
This lets the gas flow around your valves smoothly, and less turbulence here pays off later. (However, some tumble and turbulence can be a good thing on the intake side at low speeds, it mixes your air/fuel better.)
Larger valves are a must. (Mine are 1mm over size compared to stock.)
There have been a few who have used 2JZ valves which are 1.5mm OS, but are .05mm longer than stock, so they have to be cut down to work right. (There is a line of thought to have your cams re-ground to a smaller base circle and use the extra left over to increase lift and duration, but I have not yet seen it done.)
Whatever you do, replace your valve springs. Comp Cams sells "Inner Valve Springs for a Big Block Chevy" that are a tight fit in the 7MGTE head. (They work great, have higher seat and installed pressure, and better coil bind so you can run higher lift cams in the future if you want with no problems there.) Best part is these springs are like 70.00 for 24 of them.
I spent most of my time porting out the exhaust side. You want to leave a 1mm lip between the gasket size, and the port size. This is an anti reversion dam, and really helps on the log manifolds to keep your tourqe numbers high. (I did mine with 1mm lips, and Dr. Jonez removed his, and the tourqe numbers were better on my car, but his top end flow numbers are better, so everything is a trade off.)
If your going to run a tubular manifold, and it's built right, I'm not sure you need the lip so much.
I built my motor with a log type manifold in mind, but now that I'm changing over to the tube one, I've found just playing with compressed air, that the Ebay tubular one actually creates a pretty good venturi effect, and it draws air down the other tubes when you blow air into the tubes next to it... This scavange effect would make the tourqe numbers better at low to medium RPM, and since the runners are larger than stock allow for optimum top end power as well.
One tip is to use an old valve, or valves to protect your head when porting the chambers.
You want so very carefully smooth all sharp edges, and remove the material with sharp edges around where they cut the valve seats. (Blending the bowl is what I've heard it called.)This lets the gas flow around your valves smoothly, and less turbulence here pays off later. (However, some tumble and turbulence can be a good thing on the intake side at low speeds, it mixes your air/fuel better.)
whenmunkysfly said:
yes i know thats alot of power to drive arould on the street but i plan to detune the car for pump gas and run it arould at about 300 horse on very low boost, just cus speeding is bad... but anyway im building the motor for high horse and have the turbo kit and aem ems, it is part by part it the olny way i can afford it, my back round with supras is olny about a year old but i know cars, so im not scared of a high horse 7m
Adjuster said:I did mine, it was not that hard, but I'm pretty mechanically minded.
Larger valves are a must. (Mine are 1mm over size compared to stock.)
There have been a few who have used 2JZ valves which are 1.5mm OS, but are .05mm longer than stock, so they have to be cut down to work right. (There is a line of thought to have your cams re-ground to a smaller base circle and use the extra left over to increase lift and duration, but I have not yet seen it done.)
Whatever you do, replace your valve springs. Comp Cams sells "Inner Valve Springs for a Big Block Chevy" that are a tight fit in the 7MGTE head. (They work great, have higher seat and installed pressure, and better coil bind so you can run higher lift cams in the future if you want with no problems there.) Best part is these springs are like 70.00 for 24 of them.
I spent most of my time porting out the exhaust side. You want to leave a 1mm lip between the gasket size, and the port size. This is an anti reversion dam, and really helps on the log manifolds to keep your tourqe numbers high. (I did mine with 1mm lips, and Dr. Jonez removed his, and the tourqe numbers were better on my car, but his top end flow numbers are better, so everything is a trade off.)
If your going to run a tubular manifold, and it's built right, I'm not sure you need the lip so much.
I built my motor with a log type manifold in mind, but now that I'm changing over to the tube one, I've found just playing with compressed air, that the Ebay tubular one actually creates a pretty good venturi effect, and it draws air down the other tubes when you blow air into the tubes next to it... This scavange effect would make the tourqe numbers better at low to medium RPM, and since the runners are larger than stock allow for optimum top end power as well.
One tip is to use an old valve, or valves to protect your head when porting the chambers.
This lets the gas flow around your valves smoothly, and less turbulence here pays off later. (However, some tumble and turbulence can be a good thing on the intake side at low speeds, it mixes your air/fuel better.)
very intresting porting tips i might end up porting it then sending to be finished but as for 2jz valves i want to try those what do you have to do to get them to work? mill the stem then re cut the grove i asume? how much has to be ground also are they heaver than our valves?
Adjuster said:I did mine, it was not that hard, but I'm pretty mechanically minded.
Larger valves are a must. (Mine are 1mm over size compared to stock.)
There have been a few who have used 2JZ valves which are 1.5mm OS, but are .05mm longer than stock, so they have to be cut down to work right. (There is a line of thought to have your cams re-ground to a smaller base circle and use the extra left over to increase lift and duration, but I have not yet seen it done.)
Whatever you do, replace your valve springs. Comp Cams sells "Inner Valve Springs for a Big Block Chevy" that are a tight fit in the 7MGTE head. (They work great, have higher seat and installed pressure, and better coil bind so you can run higher lift cams in the future if you want with no problems there.) Best part is these springs are like 70.00 for 24 of them.
I spent most of my time porting out the exhaust side. You want to leave a 1mm lip between the gasket size, and the port size. This is an anti reversion dam, and really helps on the log manifolds to keep your tourqe numbers high. (I did mine with 1mm lips, and Dr. Jonez removed his, and the tourqe numbers were better on my car, but his top end flow numbers are better, so everything is a trade off.)
If your going to run a tubular manifold, and it's built right, I'm not sure you need the lip so much.
I built my motor with a log type manifold in mind, but now that I'm changing over to the tube one, I've found just playing with compressed air, that the Ebay tubular one actually creates a pretty good venturi effect, and it draws air down the other tubes when you blow air into the tubes next to it... This scavange effect would make the tourqe numbers better at low to medium RPM, and since the runners are larger than stock allow for optimum top end power as well.
One tip is to use an old valve, or valves to protect your head when porting the chambers.
This lets the gas flow around your valves smoothly, and less turbulence here pays off later. (However, some tumble and turbulence can be a good thing on the intake side at low speeds, it mixes your air/fuel better.)
I had Richard at ted components test the comp valve springs.
I have a pic of the results, but basically the stock spring and the comp one's binded the same, or the comp binded faster can't recall. The comp spring was just longer, that's why he said the seat pressure was much higher, iirc it was 55lbs. Some dual valve springs are not even that high.
He said it might wear out the cam faster overtime. For a replacement though, he said it was stil an improvement over the stockers.
i am still debating about doing my head i just wounder if i cna tune it proper after words
ps going to use 2j vavles they go for like 27 a pop here but then i looked online an cartec i think makes stock size vavles and there cheeper then oem and mabye better ?????
and goig to use the chevy springs as well and re use the stock retianers my buddy is saying use tie ones but really i don't think there needed that bad
in less some one say's other
and ajuster nice idea on the cam thing if that dude bc cower get the stuff doen i am so buying a set
ps going to use 2j vavles they go for like 27 a pop here but then i looked online an cartec i think makes stock size vavles and there cheeper then oem and mabye better ?????
and goig to use the chevy springs as well and re use the stock retianers my buddy is saying use tie ones but really i don't think there needed that bad
in less some one say's other
and ajuster nice idea on the cam thing if that dude bc cower get the stuff doen i am so buying a set
spoolint78 said:
i posted that along time ago on sf got flamed to hell cause i said it whoudl were out the cam caps faster
but really long whoudl ti take to were ou the cam cap and cam lopbes that what i am woundering this time i want t try em out thou cause some peoepl ahve bena runing them for a long time
i know he had the stock exhaust mani ported... don't know about anything else thoughNick M said:
i see that makes since...lol i love turbos. as far as IJ im not saying it cant be done just not the best thing for the average person. yea i didnt think about the weaght ether that is a good point? my point was that someone who has never handled that power to weaght ratio is gonna have trouble with controling the car. unless they build the engine part by part then they will learn slowly as the car slowly gains hp or not so slowly for thouse with more money lol.bowtiebuba said: