Intake porting question

[t3intercooled]

I had my motor rebuilt prior to last summer, I have aout 10-15 thousand miles on the new rebuild. Now I am thinking of taking off the manifold and getting it ported by the guy that does them on this board. I was curious should I do it now and take the intake off, get it ported, and put all new seals or should I wait and do it if I do another rebuild? Would it be worth it to unbolt the whole top half of the motor to get it ported or not?

 

[VadersV6]

I had my motor rebuilt prior to last summer, I have aout 10-15 thousand miles on the new rebuild. Now I am thinking of taking off the manifold and getting it ported by the guy that does them on this board. I was curious should I do it now and take the intake off, get it ported, and put all new seals or should I wait and do it if I do another rebuild? Would it be worth it to unbolt the whole top half of the motor to get it ported or not?

On a motor pushing 18psi or so, you'll see about a 2psi drop, meaning the restriction has been reduced. That alone will be worth about 30hp. Port the heads as well, and between a ported intake and a GOOD port job, you can see as much as a 7-8psi drop. Thats a major reduction in flow restriction, and when you crank the boost back up to where it was before, you'll have 80hp or more of a gain, and no added knock tendency. But this is only if the people know what they're doing. I have a ported intake, but my heads really arent ported. When I had the intake off, it looked like they just did a pocket port, and a crappy job at that. I was never sure about how well my intake gasket was sealing. When I ported the intake and swapped out the gasket with a 1 piece fel pro pan style gasket, I couldnt believe how much better it ran. And the gain in power was significant. The stock intake manifold ports are so small its ridiculous. Much smaller than the ports on stock heads. You can make some decent gains now, and then later if you port your heads, the heads will work that much better since you dont have an intake with straw sized ports choking the flow off.

 

[t3intercooled]

On a motor pushing 18psi or so, you'll see about a 2psi drop, meaning the restriction has been reduced. That alone will be worth about 30hp. Port the heads as well, and between a ported intake and a GOOD port job, you can see as much as a 7-8psi drop. Thats a major reduction in flow restriction, and when you crank the boost back up to where it was before, you'll have 80hp or more of a gain, and no added knock tendency. But this is only if the people know what they're doing. I have a ported intake, but my heads really arent ported. When I had the intake off, it looked like they just did a pocket port, and a crappy job at that. I was never sure about how well my intake gasket was sealing. When I ported the intake and swapped out the gasket with a 1 piece fel pro pan style gasket, I couldnt believe how much better it ran. And the gain in power was significant. The stock intake manifold ports are so small its ridiculous. Much smaller than the ports on stock heads. You can make some decent gains now, and then later if you port your heads, the heads will work that much better since you dont have an intake with straw sized ports choking the flow off.

My heads were done by a VERY reputible shop here are the flow numbers:

THE NUMBERS LISTED ARE WITH LIFT FROM .100 TO .600
INTAKE
50 106 147 155 158 159 Stock
61 121 166 180 185 186 Street/Strip Port

EXHAUST
45 83 103 109 111 112 Stock
55 112 145 176 181 182 Street/Strip Port

With these numbers do you think it will be worth it VadersV6

 

[Danster]

Who ports the intake on this board?

Dannyo

 

[t3intercooled]

Who ports the intake on this board?

Dannyo

VadersV6

 

[VadersV6]

Ive seen some pretty terrible porting jobs done by "reputable" people on the TR boards. They're heads I wouldnt put on grandma's buick let alone my car. I hope you arent one of the victims. Your flow numbers are good but in my opinion should be better if they were actually ported. Hopefully they didnt just hand you a generic flow sheet that they hand everyone. Ive seen so many crooks out there charging big bucks for crap work, and somehow through good bull****ting skills, manage to maintain their good reputation while continuing to provide crap work. And seeing a flow result for each runner would be nice, since the runners could vary as much as 30% on a bad job. What work was done exactly? Any porting of the runner or pocket? Any valve back cuts or special valve job?
Regardless, if you have ported heads, a stock intake is a huge bottleneck. You may still be able to crank the boost up and run a good time, but the turbo will work alot harder and heat the air up alot more than it would if a ported intake were matched to the heads. Always think of the intake and the heads as 1 integrated unit. The runner doesnt start at the intake mating surface. It starts at the plenum. If it starts off big, then tapers small then hits a huge expansion then gets compressed again as it goes through the valve throat, then expands again into the cylinder, the coefficient of discharge is all wacked and is hurting what potential the ported heads can provide....if the heads were done right that is. If they werent done right, then a ported intake and any other speed part wont work as it could.

 

[t3intercooled]

Ive seen some pretty terrible porting jobs done by "reputable" people on the TR boards. They're heads I wouldnt put on grandma's buick let alone my car. I hope you arent one of the victims. Your flow numbers are good but in my opinion should be better if they were actually ported. Hopefully they didnt just hand you a generic flow sheet that they hand everyone. Ive seen so many crooks out there charging big bucks for crap work, and somehow through good bull****ting skills, manage to maintain their good reputation while continuing to provide crap work. And seeing a flow result for each runner would be nice, since the runners could vary as much as 30% on a bad job. What work was done exactly? Any porting of the runner or pocket? Any valve back cuts or special valve job?
Regardless, if you have ported heads, a stock intake is a huge bottleneck. You may still be able to crank the boost up and run a good time, but the turbo will work alot harder and heat the air up alot more than it would if a ported intake were matched to the heads. Always think of the intake and the heads as 1 integrated unit. The runner doesnt start at the intake mating surface. It starts at the plenum. If it starts off big, then tapers small then hits a huge expansion then gets compressed again as it goes through the valve throat, then expands again into the cylinder, the coefficient of discharge is all wacked and is hurting what potential the ported heads can provide....if the heads were done right that is. If they werent done right, then a ported intake and any other speed part wont work as it could.

When you do them do you need the heads too or just the intake?

 

[turbofabricator]

Just porting the intake manifold is really not worth the hassle. Do them at the same time as your heads.

 

[VadersV6]

Just porting the intake manifold is really not worth the hassle. Do them at the same time as your heads.

Well it is worth the hassle, given the ports are small enough that porting the intake is worth 2-3 tenths and a 2psi drop with stock heads. Regardless, his heads are already ported. Guess you didnt see that part.
As far as needing the heads- I dont need the heads but it is nice to have the old gasket, so I can see the outline of the ports on your heads and match the intake to it. Whatever you do, dont wipe the gaskets so clean that the outline disappears.
I'm considering machining up some fixtures and writing some code to CNC the ports in the future, (Been a cnc programmer for 10 years and ported my first set of heads 20 years ago) but I need a donor intake to do it. Not as in, an intake I can trash, but an intake to map out the ports, and CNC port. But it wouldnt be ported through the entire length of the runners, since its not only not necessary, given the heavy taper of the runners, but I also would need a 5 axis CNC to do more complex 3 dimensional curves. I have 3 axis NC's. But the next intake I do, I would have to have for a month or so, so I can get the code right for future intakes. The taper of the runners is so steep that simply opening up the last couple inches can improve flow dramatically, and naturally a CNC ported intake would be accurate and balanced, runner to runner.

 

[t3intercooled]

Well it is worth the hassle, given the ports are small enough that porting the intake is worth 2-3 tenths and a 2psi drop with stock heads. Regardless, his heads are already ported. Guess you didnt see that part.
As far as needing the heads- I dont need the heads but it is nice to have the old gasket, so I can see the outline of the ports on your heads and match the intake to it. Whatever you do, dont wipe the gaskets so clean that the outline disappears.
I'm considering machining up some fixtures and writing some code to CNC the ports in the future, (Been a cnc programmer for 10 years and ported my first set of heads 20 years ago) but I need a donor intake to do it. Not as in, an intake I can trash, but an intake to map out the ports, and CNC port. But it wouldnt be ported through the entire length of the runners, since its not only not necessary, given the heavy taper of the runners, but I also would need a 5 axis CNC to do more complex 3 dimensional curves. I have 3 axis NC's. But the next intake I do, I would have to have for a month or so, so I can get the code right for future intakes. The taper of the runners is so steep that simply opening up the last couple inches can improve flow dramatically, and naturally a CNC ported intake would be accurate and balanced, runner to runner.

When you say the old gasket, you mean the old intake valley pan gasket correct?

 

[VadersV6]

If its a 1 piece gasket, then yes. Whatever comes off your car. It leaves a witness mark that becomes the template for the new port.

 

[t3intercooled]

Sounds good, would it be good to maybe trace the markings with a permanent marker so it doesn't get wiped off, I and if I sent it to you now, I should be able to get it by april 1st is that right? Also here do I send it?

 

[t3intercooled]

And you charge 175 shipped is that right? Do ou need that right away or when your ready to ship

 

[VadersV6]

And you charge 175 shipped is that right? Do ou need that right away or when your ready to ship

Ive decided, given the huge response via PM's, that Im not going to do any hand porting. I simply dont have that much time to do it all by hand. Im going to develop some CNC routines and fixtures and do all future intakes in my Fadal. Given the heavy taper, as I mentioned earlier, you only have to go in a couple inches to get a dramatic improvement in flow. This porting will consist of CNC porting all the runner exits, about 2 inches in, polishing out any problem casting flash and core shift, blending the first section of the runners into the CNC'd areas and doing a general cleanup and deburr. It'll be $200 plus shipping costs. Just another 25 bucks for CNC'd ports instead of hand work which can be inconsistent.
Ive got a guy sending me an intake, who is going to give me enough time to develop the fixtures and programming, and get it all dialed in. If others are willing to wait a couple months at most, I can take the intakes now if desired.
If there are others interested, please PM instead of posting here. Dont want to upset the powers that be