Porting & polishing intake and heads
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Porting & polishing intake and heads
I have a stock LT1 except for Corsa exhaust. Would there be any appreciable gain or benefit in horsepower/acceleration by having the intake and heads ported and polished if that was all that was done for the time being?
Or would doing so just be a big waste of time and money? Opinions please?
Or would doing so just be a big waste of time and money? Opinions please?
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Re: Porting & polishing intake and heads (BryanC)
Its worth it, even with a stock cam. But if you did a cam change, you could see huge gains.
#5
Le Mans Master
Re: Porting & polishing intake and heads (vader86)
Its worth it, even with a stock cam. But if you did a cam change, you could see huge gains.
Just make sure that you have a clear goal in mind for what you want. Spending money twice on the same thing really sucks... Porting heads will definatly give you again, and more so with a cam, so what you should do is pick a cam out NOW before you port the heads, and tell the person doing the head work the cam numbers, then they can better match the heads to the cam. Or, if you think you'll be going 383ci+ down the road, have them port the heads for a 383...you'll lose a tiny amount of power now, but the heads will just need to be freshened up when you do the rebuild. Just my opinion... :cheers:
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Re: Porting & polishing intake and heads (BryanC)
Quote:
"Definitely worth it. Although it's the easiest time to go ahead and do the cam as long as you are that far into the engine."
I don't mean to start an argument or anything, but recently I've read quite a few comments regarding the Hotcam as not being really a good idea for an automatic LT1, unless one wants to get really carried away with modifications. I've got to completely "rethink" this cam business before I go too deep into that part of the modding.
I want 3.31 gears but am told they are rarer than finding teeth in a duck's bill. I may just end up with the 3.54's, but rather than sit around and do nothing all winter, I just thought I would at least get some of the "top-end" work done now and wondered there would be any noticeable improvement to justify the expense.
I have been told, that a cam can be changed without pulling the intake. Is that true? I mean, can it be done RIGHT? I did it on my old Mopar 440, but don't know about these Chevy 350's.
I have no plans to go to anything like a 383 or 396 or the like. No long tube headers in the future either, but maybe a set of "shorties" down the road.
Karl
[Modified by MagikDraggin, 11:40 PM 2/23/2003]
"Definitely worth it. Although it's the easiest time to go ahead and do the cam as long as you are that far into the engine."
I don't mean to start an argument or anything, but recently I've read quite a few comments regarding the Hotcam as not being really a good idea for an automatic LT1, unless one wants to get really carried away with modifications. I've got to completely "rethink" this cam business before I go too deep into that part of the modding.
I want 3.31 gears but am told they are rarer than finding teeth in a duck's bill. I may just end up with the 3.54's, but rather than sit around and do nothing all winter, I just thought I would at least get some of the "top-end" work done now and wondered there would be any noticeable improvement to justify the expense.
I have been told, that a cam can be changed without pulling the intake. Is that true? I mean, can it be done RIGHT? I did it on my old Mopar 440, but don't know about these Chevy 350's.
I have no plans to go to anything like a 383 or 396 or the like. No long tube headers in the future either, but maybe a set of "shorties" down the road.
Karl
[Modified by MagikDraggin, 11:40 PM 2/23/2003]
#7
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Re: Porting & polishing intake and heads (MagikDraggin)
The key if you're going to port the heads is to port them WITHOUT opening up the port volume appreciably. If you simply clean up the casting flash and port match everything, you'll pick up a lot of top end flow as well as low end. It IS possible to hurt your low lift flow if you get carried away with the porting, which doesn't matter TOO much if you're running a higher lift cam where you're spending more time at the higher flow numbers anyway. But if you're staying with the stock cam, just go in and clean up the casting flash and gasket match.
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Re: Porting & polishing intake and heads (MagikDraggin)
Ok, I guess that's all I'm going to hear out of the "Night crew". What does the "Day crew" have to say about this?
I do not want to build a drag car. I do a lot of hwy and intown driving. I do not want to lose that driveability nor much of the fuel economy that I already have.
What I want to know is whether doing the intake/head work now is a good idea? And what else can I do at this time to compliment that work, OTHER than a radical cam, and some higher gears, which will help the car go a little quicker from stoplite to stoplite?
Anything? Or am I simply asking for the "impossible dream", of having my cake and being able to eat it too?
(It's not wrong to ask is it?) :seeya
I do not want to build a drag car. I do a lot of hwy and intown driving. I do not want to lose that driveability nor much of the fuel economy that I already have.
What I want to know is whether doing the intake/head work now is a good idea? And what else can I do at this time to compliment that work, OTHER than a radical cam, and some higher gears, which will help the car go a little quicker from stoplite to stoplite?
Anything? Or am I simply asking for the "impossible dream", of having my cake and being able to eat it too?
(It's not wrong to ask is it?) :seeya
#9
Burning Brakes
Re: Porting & polishing intake and heads (MagikDraggin)
Keep your driveabilty and gas mileage,but add 150 horsepower.
One word.............NITROUS!!! :party:
One word.............NITROUS!!! :party:
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Re: Porting & polishing intake and heads (MagikDraggin)
For a nice power increase without touching the cam do a pocket port, clean up head and intake flashing, smooth intake and exhaust passages and add 1.6:1 ProMagnum RRs.
This will allow your stock cam to better use the increased air flow from the intake & heads work.
If you like a more agressive exhaust note do a hi-flow cat-back for a little more gain.
Then tune fuel flow at WOT with an AFPR and you'll have a very streetable Vette with nice boost in power.
This will allow your stock cam to better use the increased air flow from the intake & heads work.
If you like a more agressive exhaust note do a hi-flow cat-back for a little more gain.
Then tune fuel flow at WOT with an AFPR and you'll have a very streetable Vette with nice boost in power.
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Re: Porting & polishing intake and heads (65Z01)
Thank you so much for your reponse 65Z01. It is mucho appreciated!
You mentioned the addition of 1.6 rocker arms. Will these cause a need to have the computor reprogrammed for any reason? And as I boldly display my overall ignorance of these things, what exactly does AFPR mean?
Thanks again.
Karl
You mentioned the addition of 1.6 rocker arms. Will these cause a need to have the computor reprogrammed for any reason? And as I boldly display my overall ignorance of these things, what exactly does AFPR mean?
Thanks again.
Karl
#12
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Re: Porting & polishing intake and heads (MagikDraggin)
Magik : With 1.6 roller rockers you do not need to reprogram your PCM. AFPR stands for Adjustable Fuel Pressure Regulator. I hear it helps a lot when you set it correctly ( especially on modified motors ). Good luck!
Michael
Michael
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Re: Porting & polishing intake and heads (MagikDraggin)
I have been told, that a cam can be changed without pulling the intake. Is that true? I mean, can it be done RIGHT? I did it on my old Mopar 440, but don't know about these Chevy 350
[Modified by MagikDraggin, 11:40 PM 2/23/2003]
[Modified by MagikDraggin, 11:40 PM 2/23/2003]
#14
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Re: Porting & polishing intake and heads (flyersfan1088)
As far as I know the cam can't be changed with intake on unless you have pop-up lifters. I could be wrong, though
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Re: Porting & polishing intake and heads (MagikDraggin)
I just remembered this thread from 15 months ago, has some good info regarding the original question:
http://forums.corvetteforum.com/zerothread?id=185508
http://forums.corvetteforum.com/zerothread?id=185508
#16
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Re: Porting & polishing intake and heads (Vince Ivanc)
Removing the intake is a fairly straight forward task and isn't difficult. Doing a cam or head swap is best left to the experienced or pro. There is a lot involved in doing a cam swap with the engine still installed.
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Re: Porting & polishing intake and heads (MagikDraggin)
VINCE: a 22hp gain on only doing the heads/intake....unreal! On my old Mopar 440, the lifters could be removed after pulling the pushrods w/o removing the intake.
GOODY: I am already thoroughly intimidated by looking under the hood of my '96. I will definitely leave any camwork (or any other topend work) on my Corvette to the pros. I'm just not that "gutzy" with these "newer" cars, even if the mechanics is essentially the same.
FLYERSFAN1088: Pop-up lifters? Not familiar with that term. Thanks for the comeback, though.
BLACK96CORVETTE: Thanks for the info on the AFPR. I would never have guessed those phonets.
I appreciate all those who responded. Now I have a pretty good idea of where I'm heading with the first of these mods. Glad you all took the time.
Karl
GOODY: I am already thoroughly intimidated by looking under the hood of my '96. I will definitely leave any camwork (or any other topend work) on my Corvette to the pros. I'm just not that "gutzy" with these "newer" cars, even if the mechanics is essentially the same.
FLYERSFAN1088: Pop-up lifters? Not familiar with that term. Thanks for the comeback, though.
BLACK96CORVETTE: Thanks for the info on the AFPR. I would never have guessed those phonets.
I appreciate all those who responded. Now I have a pretty good idea of where I'm heading with the first of these mods. Glad you all took the time.
Karl