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Port and Polish


topless94style

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So my dad wants me to get the Oring fixed on my car. He said hell pay for it on the credit card and i can pay him back. I know they have to remove a head and the intake. If i get them to remove the other head and exhaust manifolds does anyone think theyll let me take them all in to get ported and polished? along with a 5 angle valve job. Also does anyone know what the port and stuff would cost? Also, What would be my new hp/tq numbers.

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As far as having the shop mechanic remove the other cylinder head and exhaust manifold for you, sure they'll do it. But you have to pay extra labour for them to do it for you.

 

If you take your cylinder heads to get it ported and polished, it'll obviously gain some horsepower but it'll cost you because that's an expensive modification.

 

Just remember that not all cylinder porting and polishing work is equal, no two shops do the same quality of work. It all boils down to experience. This is the stuff you do not want to go cheap on.

You may find a bargain but just be sure you know what you're paying for.

 

You can gain anywhere from 10HP to 25HP easily, depending on the quality of the work. I can't tell you exact figures and I definitely can't tell you at what RPM you're new-found power will be. The only actual way to find out is have the work done then have your engine or your vehicle itself dyno tested. That too is expensive, so it's up to you whether or not you want to find out exactly how much power you gained. Just remember that you can gain significant amounts of power. I've read of a GTP owner having his DOHC multi-valve cylinder heads ported on his 3.4L Twin Cam and he dyno tested his car. His gains were roughly 40HP and 30lb-ft of torque at the wheels! That's quite a bit, almost to the point of being unbelievable. However, just remember there's more surface area in a DOHC multi-valve motor so you probably wouldn't gain that much on your OHV engine.

 

Let us know how it turns out.

 

So my dad wants me to get the Oring fixed on my car. He said hell pay for it on the credit card and i can pay him back. I know they have to remove a head and the intake. If i get them to remove the other head and exhaust manifolds does anyone think theyll let me take them all in to get ported and polished? along with a 5 angle valve job. Also does anyone know what the port and stuff would cost? Also, What would be my new hp/tq numbers.
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I know it will be expensive. I am going down to the napa machine shop today to check out prices and then ill probably go to competition engines and see what they can do. The reason why i would go to napa is because i know the guy down their and he does good work. I have brought in parts before to have him work on them and so have friends have mine. Hopefully, hell be easy on prices because he usually gives a high quote and when you go to pay for it its an unbelievably good deal. I took my head in off my old truck to get two broken bolts taken out he said it would be $40 per bolt and when i went in he charged me $30 total. That same type of thing has happened to two of my friends who have use him. Ill come back with some prices.

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Napa wont port anything but he will do a valve job for $350-400. Now i know how to do a valve job i just dont have the equipment i might have to go back to high school and see if theyll let me do it there. Porting i have no idea how so im gonna have to search around for that.

 

He also said that the valve job would see the most power gains than porting and polishing would. He said that if i ran a little bit bigger cam with the valve job i would see good gains. But ive never heard of bigger cams for a V6 engine.

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But ive never heard of bigger cams for a V6 engine.

 

 

Bigger cams are available for the 2.8, 3.1, 3100, 3400, 3800, and 4.3. However, they are not available, as far as I know, for the 3.4, besides the fact that the 3.4 has 4 of them and that gets quite expensive.

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Well i got a friend that knows how to do the porting, he graduated from a local tech college as a mechanic and i know how to do the valve job but this is only on the head as far as i know. I got a quote from a engine rebuild shop that said it would be $200 per head to port polish and i think a valve job.

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200 bucks is way too cheap for head work on a DOHC. Also, you want a shop that has done the DOHC before or at least understands your goals. You can't just say "port it" and get what you want. I have done a few sets of DOHC heads and can tell you that you can kill your low end by doing one thing wrong. The high end kicks ass that way but in an auto, you will hate it. Another way will give you awesome low end and still better high end (but not as much as the other way).

 

The machine shop here does a 5 angle valve job on the DOHC for less than 150.

 

The 3.4 cams can be reground, but I dont know what specs (i am having a set done for someone else's engine).

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The guy seemed to know what he was talkin about as he mentioned that i would have to bring in the cam assembly so they can continue to get it all tuned and working together. I think that was just the porting and not he valve job. Did i mention napa would do it for $350? I called another shop and they said about $275 total. More help on this is hiley appreciated so anyone and everyone help me out so i dont mess anything up.

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If i get all this work done to my car along with performance exhaust and a K&N drop in, am i gonna blow my tranny? What about my rod bearings will they hold up? What would it take to put in a Getrag 282 in my car. I know ill need to do the conversion but would i have to get the ecm from the car it came out of?

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I don't agree with that. You don't see shops offering "Horsepower Increasing Valve Jobs" and shit like that. But you do see shops offering "Cylinder Head Performance Porting" and such. Not to say you can' t gain power from a valve job, but a valve job simply can't increase the airflow like a good cylinder head porting and polishing job can.

 

He also said that the valve job would see the most power gains than porting and polishing would. He said that if i ran a little bit bigger cam with the valve job i would see good gains. But ive never heard of bigger cams for a V6 engine.

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I would love to see a "cam'd" 3.4L Twin Cam. I can only imagine what type of power it would make. :)

 

I never knew there were aftermarket camshafts for the 2.8 MPFI, 3.1 MPFI, or 3400 SFI. I know there are cams available for the 3100 SFI and the 3800 Series II and L67 though. Where can I find these cams?

 

But ive never heard of bigger cams for a V6 engine.

 

 

Bigger cams are available for the 2.8, 3.1, 3100, 3400, 3800, and 4.3. However, they are not available, as far as I know, for the 3.4, besides the fact that the 3.4 has 4 of them and that gets quite expensive.

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There are no cams for the 3100 or 3400, they are regrinds. There may be some in the future but not now. The flat tappet 60V6 pushrods have a ton of choices.

 

If a shop told you that, run away. I wouldn't let them touch my heads if they told me a valve job does more than port work.

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Guest TurboSedan
I wouldn't let them touch my heads if they told me a valve job does more than port work.

 

 

hashaha i just found that last sentence funny....almost perverse sounding. nevermind i must be high hehehe

joshua

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Yea im not gonna let that guy do shit to my heads. Since i know how to do a valve job im gonna see if i can get back into high school in the fall and do it there since they have the equip. Sometimes though, those napa guys are full of shit. They have tried to fill me full of bs and buy all this expensive shit i dont need. I dont know why i keep going back prolly cuz its the closest parts store.

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Well i got a friend that knows how to do the porting, he graduated from a local tech college as a mechanic and i know how to do the valve job but this is only on the head as far as i know. I got a quote from a engine rebuild shop that said it would be $200 per head to port polish and i think a valve job.

 

valve jobs are the EASIEST part of internal engine modding, you just need the right grinding tools

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Heh heh! In a way it sort of does sound perverse.

 

Seriously though, a valve job can never produce as much power as a port and polish job. I've seen port and polish jobs bring out up to 46HP and 38lb-ft on an LT-1 by itself with no other mods. You will never be able to get that type of power by a valve job by itself. Even if you upgrade to larger valves, you still won't gain that kind of power. That's either complete ignorance, stupidity or inexperience. Don't get me wrong, I'm not trying to trash talk your sources, but internal engine work is something you take to a real professional. You don't want to have some goofball work on your heads and ruin your engine, all at the same time you get ripped off.

 

I wouldn't let them touch my heads if they told me a valve job does more than port work.

 

 

hashaha i just found that last sentence funny....almost perverse sounding. nevermind i must be high hehehe

joshua

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Yea thats why i am gettin a set of heads from the junkyard. Im and gonna get them boiled shaved and checked for cracks then i am gonna do the valve job myself. Porting i am still looking for a good place. Then if it works out on those heads i can just swap them on the motor.

 

I cant find a place that will port and polish my intake/exhaust manifolds though. Maybe i havent looked hard enough.

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I do that kind of work (intake, heads). Exhaust really isn't worth porting for the cost/hp gains.

 

Don't have the heads put in the caustic solution. its the first thing that came to mind when you said boiled. That stuff will eat your heads.

 

I have a spare set of heads here as well, fyi.

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UNLESS your running boost where evacuation is very important!!

Spend the coin and do the port and polish, but engine is not flowing enough to warrent a 5 angle, 3 angle would suffice.

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What are you talking about with that first sentence?

 

A 5 angle is better because it is a smoother transition. That means less turbulence. A valve job isn't necessarily for quantity of flow (though it does effect it), but rather quality of flow. With boost, you can just hog things out for the most part, which would kill your velocity at low RPMs on an NA or even a turbo with lag.

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Sorry, about exhaust porting. once the heads off the cost should be insignificant if not nonexistant,porting is porting it's all about flow, so if you can get it in faster you have to get it out faster. The best cure for lag is to improve the exhaust side, but improving the exhaust without touching the intake will kill your torque levels. Vegeta is right about the valve job on Na ( I'm so used to my GN :oops: )

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ok so i'm really new at this...

 

what's the difference between a five-angle and a three-angle valve job, and what would you guys expect the cost to be for a quality port/polish intake and/or exhaust job?

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First a 5 angle job has more angles allows for a better seal and better flow for more power. Second does anyone know any good sites to read up on porting and polishing? Im curious and doing it myself not just to the heads but to the intake.

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It wont create a better seal. THere is 1 angle that does the sealing, and it is the 45 degree angle.

 

Well, if the 60v6 site wasn't messed up I could link you to something for the heads. I think I had something on the intakes as well, but I have more I needed to add anyway.

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