Is porting a 2g head worth it?

[CodeMonkey]

I've been trying to decide if it's worth it to port my 2G head and I haven't been able to find any before-after dyno numbers at all....

It's obviously very expensive and I get the feeling my money would be better spent elsewhere, but I don't have enough info to make a decision. Any _facts_ anyone has on HP gains from porting the head would be appreciated.

 

[stephenz]

you could port a 2g head more than a 1g,you could actually raise the runners and plug off the injector holes and run them on the intake manifold runners.


stephen.

 

[gixrman]

Not really unless your pushing hugh amounts of air. Porting a 2g head kills the velocity of the incoming air. Gasket matching is about all you will need to do.

 

[jltcat]

you can port it and make it work better but it takes a lot of time. We did one on one of our eclipses. Have about 100 hours just in the port work. Did it as an engineering exercise.

 

[DSMJim]

Not really unless your pushing hugh amounts of air. Porting a 2g head kills the velocity of the incoming air. Gasket matching is about all you will need to do.

Yes but your talking about lowering the ports (hogging out the holes like a 1G head) which is exactly opposite to what you want to do.

What stephenz has already described is the best way to do it. A straighter line at the valves creates better flow, not a larger hole. The 1G head has a horible angled entry. Technically from a porting standpoint a head with a straighter path to the valves is a better place to start with.

 

[wishihadatalon]

So would a 2g head with all the little things like 1mm oversized valves and gasket matching be about all you would need?

 

[DSMJim]

So would a 2g head with all the little things like 1mm oversized valves and gasket matching be about all you would need?

It's gonna be all I need,yes.

 

[gSx_r1der]

It's gonna be all I need,yes.

Its going to be all you need for what ???? You gotta remember other people are reading these threads Jim to gain knowledge on what to do for their setup, this is one of the most important things on my mind right now cause i know bigger isn't always better(1g head) but i also know that the stock 2g head doesn't flow an astounding amount. So some more info on your decision or your goals and why that is enough would be awesome thanks man

 

[philly90tsi]

Just Do the 1g Swap Head and Intake Manifold. Buy a Cheap Head on Ebay and do a P&P.

 

[CodeMonkey]

Well my goals are for a street / strip car (400 whp or so).

I already got a good deal on a used 2g venom intake manifold, so I don't want to switch to a 1G head (plus I think the 2g head is better anyway).

Based on what I've heard I think the best option for me would be a simple valve job plus upgraded springs (want to set my redline to 8500), and 3g lifters (damn lifter tick). (And of course some new cams, but that's another issue).

 

[sickfast2ndgen]

if you have a dremel, you can port the head yourself. this is especially useful if all you want to do is gasket match, as you'll save yourself a lot of money.

I did a full port job on my own 2g head (matched to 1g intake manifold) with 2 or 3 of the high speed cutting bits. Look here for details. I ended up spending about an hour a port, and went about 1-3/8" deep. I've had both a 1g head and a 2g head w/1g manifold on my car, and to be honest, I cant tell the difference. I'm not making enough power.

 

[markgholland]

Choosing between a 2G head and a 1G head is dependent upon what you car is being built for... Building a street car in which you want power down low? The 2G head is for you! Are you building a strip car only that you will spend the majority of the time in the higher RPMs? Hog out a 1G head, you'll love it.

Working on the short side radi and bowls is always a good idea, not to mention it will NEVER hurt a cylinder head's performance to clean up the casting inperfections and polish it.

To whoever said they spent about an hour on each head, you're crazy! I spend about 3-5 hours on a single port, multiply that by two per cylinder and that is about 6-10 hours PER CYLINDER.

Good luck,

Mark

 

[wishihadatalon]

It's gonna be all I need,yes.

So what all is done to your head. I am really curious b/c I am getting to the next step in my setup and I am thinking about a larger turbo and some valve train stuff.

Also how would a stock 2g head flow on a stroker motor? Would it hurt it or not.

 

[gixrman]

Yes but your talking about lowering the ports (hogging out the holes like a 1G head) which is exactly opposite to what you want to do.

What stephenz has already described is the best way to do it. A straighter line at the valves creates better flow, not a larger hole. The 1G head has a horible angled entry. Technically from a porting standpoint a head with a straighter path to the valves is a better place to start with.

No I'm not, gasket matching a 2g head to a 2g intake is not hogging anything. I am totally agianst porting the 2g head to match the 1g intake if thats what your refering too.

Who the hell has done the above stated mod!!???

 

[markgholland]

Anyone who even attempts to port match a 2G head to a 1G manifold is crazy in my opinion. You would end up taking off so much material that I would be worried that you would jeopordize the strenght of the head...

~Mark

 

[DSMJim]

Lots of places take a 2g head and hog the holes out to make it like a 1g head, thats fairly common really.

The head currently on my car is stock with 101200 cams. What will be happening after race season this year is a port job to raise the runner and eliminate the injector boss and adjust my intake manifold to match. I will put the injectors into the manifold up 2" or so for better atomization and cooling effect. I'm debating on 1mm over sized valves still, so not sure there, plus standard bowl and valve/valve seat work. Standard porting on the exhaust side with more/better porting to match on my turbonetics manifold.

As I really get into it i'll decide from there exactly where I'm going but each step will be flow benched so I know if were making progress or not. It's fairly cheap around here for htat type of work so It shouldn't be much of a problem. Will have to wait until winter though because doing all that this time of year is too much waiting for me.

 

[wishihadatalon]

Lots of places take a 2g head and hog the holes out to make it like a 1g head, thats fairly common really.

The head currently on my car is stock with 101200 cams. What will be happening after race season this year is a port job to raise the runner and eliminate the injector boss and adjust my intake manifold to match. I will put the injectors into the manifold up 2" or so for better atomization and cooling effect. I'm debating on 1mm over sized valves still, so not sure there, plus standard bowl and valve/valve seat work. Standard porting on the exhaust side with more/better porting to match on my turbonetics manifold.

As I really get into it i'll decide from there exactly where I'm going but each step will be flow benched so I know if were making progress or not. It's fairly cheap around here for htat type of work so It shouldn't be much of a problem. Will have to wait until winter though because doing all that this time of year is too much waiting for me.

So all the stuff you are trying is experimental? Good luck

 

[gixrman]

Lots of places take a 2g head and hog the holes out to make it like a 1g head, thats fairly common really.

The head currently on my car is stock with 101200 cams. What will be happening after race season this year is a port job to raise the runner and eliminate the injector boss and adjust my intake manifold to match. I will put the injectors into the manifold up 2" or so for better atomization and cooling effect. I'm debating on 1mm over sized valves still, so not sure there, plus standard bowl and valve/valve seat work. Standard porting on the exhaust side with more/better porting to match on my turbonetics manifold.

As I really get into it i'll decide from there exactly where I'm going but each step will be flow benched so I know if were making progress or not. It's fairly cheap around here for htat type of work so It shouldn't be much of a problem. Will have to wait until winter though because doing all that this time of year is too much waiting for me.

I respect you and all and take your posts that you know WTF your talking about jim but how benificial do you think that will be on a forced induction motor. I know its very efficent on 4v motorcycle engines and when chevy went to the 18 degree ports on there SBC but there N/A. Do you have any sites or info on this? I'd like to follow you on this.

 

[timawdtsi]

I just had a 2.3 Stroker built by Magnus. In the process of the building the motor, I had taken the head to be cleaned and such. Discovered thing's that needed to be taken care of. At that point I mentioned that I may as well ditch the 2G head and start over and purchase a brand new 1G head rather than rebuild the 2g.
At that point he directed me to rebuild the 2G head because it flow's better than the 1G and also mentioned that they use a 2G head on 9 sec drag car.

 

[DSMJim]

So all the stuff you are trying is experimental? Good luck

I respect you and all and take your posts that you know WTF your talking about jim but how benificial do you think that will be on a forced induction motor. I know its very efficent on 4v motorcycle engines and when chevy went to the 18 degree ports on there SBC but there N/A. Do you have any sites or info on this? I'd like to follow you on this.

Well, nothing is experimental when you have a flow bench. You can do something and see how it starts to work. Head porting is as old as sliced bread, so nothing is really experimental, its more that what I'm doing is a bit different from the norm. THe fundimentals underwhich I am doing my head are age old head porting design thoery's, I'm just applying them to a 2G head in much the same way as an old chevy small block head, not applying them the same as a 1g head with it's large intake port.

Here's the thing. I will be able to make mid to low 11 second passes (not on my current turbo tho ..) on my car with the stock head, so porting isn't something I'm doing for speed because my car will go as fast as I want. I am doing more for the point that I want to see really what I can get from a 2G head and see if I can stick it to all the nay-sayers who say it can't be done.

Incase you havn't noticed I do not take the normal modding path most take. I started off by taking off all the BS mitsu stuff and replacing it all right from the get-go, manifold o2 housing etc.. I run a standard T3 flanged turbo, no mitsu hybrid shit for me. etc.. I did this 3 years ago when the FP-Green was the baddest turbo ever, so I had a regular 50trim from Turbonetics with a T3 flange. Everybody thought I was stupid for not keeping the 2g manifold as though it's the best ever. I don't like it and won't use it, period. Well the 1g head falls under the same catagory for me. I have a 6 bolt bottom end rebuild with forged shit. I don't want to use a 1g head because a 2g head is easier for the purposes of the swap. I also am not going to let the 2g head stop me from making lots of power. I'm gonna port it and make it flow better and make lots of HP.. People see the small intake ports and think it doesn't flow as much, and thats bullshit and I'm out to prove it.

 

[nanokpsi]

I just had a 2.3 Stroker built by Magnus. In the process of the building the motor, I had taken the head to be cleaned and such. Discovered thing's that needed to be taken care of. At that point I mentioned that I may as well ditch the 2G head and start over and purchase a brand new 1G head rather than rebuild the 2g.
At that point he directed me to rebuild the 2G head because it flow's better than the 1G and also mentioned that they use a 2G head on 9 sec drag car.

The 2g head only makes more power tyhan the 1g head with the aforementioned raised runner. I assure you his head isn't your run of the mill rebuilt/cleaned up 2g head.

 

[sickfast2ndgen]

I am totally agianst porting the 2g head to match the 1g intake if thats what your refering too.

Who the hell has done the above stated mod!!???

i have that mod.... and it's worked well for about 20k miles. those of you who are afraid of hitting the water jackets dont have much to fear. and yes, i really only did spend about an hour on each port. they aren't a professional job, and don't pretend to be. no mirror fininsh or anything, but they dont look like garbage either. works well enough for my DD. just my .02

 

[gixrman]

i have that mod.... and it's worked well for about 20k miles. those of you who are afraid of hitting the water jackets dont have much to fear. and yes, i really only did spend about an hour on each port. they aren't a professional job, and don't pretend to be. no mirror fininsh or anything, but they dont look like garbage either. works well enough for my DD. just my .02

I was referring to Jim's idea, sorry for the confusion.