Can i port and polish my heads and upper and lower intake and put them on a relatively stock engine?

I have headers, cold air intake, slp air temp module, tb bypass and underdrive pulleys...just so you can get an idea when i say "relatively stock"

 

yes you can, however you wont see much more power unless you add a more agressive cam.

however you will deffinetly have an improvement in gas mialage

 

You can do it.
You will get more responce through out your rpm range, not a hole lot more power, but better gas milage.
I did my, cylinder heads.

 

It will help more with a 3.4 due to the lack of air that the motor moves with stock heads.That's why they have a "dead spot" from 35 to 45mph.But yeah, heads will definately help.They will help even more when you get a cam in there!

 

see what im worried about is my 93,000 miles on the engine. My dad is telling me that if i do that the bottom end of the motor wont be able to handle it. He said he did the same thing on his 68 impala when he was a kid and a week later the bottom end gave out. Anyone have any similar problems?

 

that was just a concidence with your dad's motor. (or he had his foot in it a lot more) if you just port the heads it wont cause any harm to the rotating assembly. if you were to have the heads milled then there could be some complications with a higher compression ratio, but unless you do something crazy(10:1)(that would be crazy in my mind with a stock cam)it wont hurt much

 

Guys are turboing high mile 3.4's and there holding up great.
P&P on a stock engine will only give you about 10hp at most.

 

yea he said something around the area of the compression being low on my engine b/c of the miles and that porting and polishing it would highten the compression where the engine wouldnt be able to handle it. Then again with tech the way it is today a 68 engine is prob diff compared to todays engines so... iight well thanks guys for the answers, much appreciated

 

porting the heads will not alter the compression ratio one bit, if you were to polish the bowls of the heads then you would actually lower the compression ratio a hair

 

iight thanks. O and by the way im looking at ur sig and all the stuff uve done..Have you ever ran yours at the track and if so, what did it run?

 

yeah i ran at the track a year and a half ago... that was only when i had a few of the mods (i think the pulley, CAI and catback) , it was really hot and humid (like 90* and 80-90% humid)but it squeaked out a 15.935 (and the motor was pretty freaking hot since i drove it an hour to the track)

but i havnt ran it since any of the other stuff has gone in because all summer i worked nights and weekends, hopefully that wont be the case this summer

 

thats a good amount of time to shave off from just those mods. I heard our cars run 16.7-16.9 stock. Nice job

 

thank ya