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-   -   should i polish my heads (https://www.racingjunk.com/forums/showthread.php?t=19554)

olds48 01-18-2008 03:58 PM

should i polish my heads
 
I have a 496 BBC with a set of Canfields.I port matched them to a Felpro 1275 intake gasket,plus the standard bowl blending blahblahblah.....Thing is I only slightly smoothed them out,since I was running the car on the street mostly.Now it spends 80% of its time at the track.Is it worth the troble to go back and put a real smooth polish in the heads?I'm running brackets,so I don't need every ounce of power available,plus I only rev the motor to 7000 MAX.No need to ring out a bracket motor.Would it help consistency any?

altune 01-18-2008 06:27 PM

Polish the exhaust only
intake should be slightly rough
polished combustion area is ok.

olds48 01-18-2008 11:26 PM

Really?Whats the reason for that?

cepx111 01-18-2008 11:27 PM

Anything you can smooth out in the heads and intake will help flow and will build upper rpm HP which I'm not sure is something you'd tap into that much if your only reving to 7 grand, also I agree with what the other reply stated you dont want a super smooth intake port, you want it some what rough to help keep the air / fuel mixture atomized before going into the clyinder rather than having it bead up in the port.
Now, as far as making the car any more consistent?
I don't think you will notice any change there.
The biggest thing I've found that makes a car consistent in bracket racing is by doing the SAMETHING EVERYTIME!
I.E. Same burnout, staging in "EXACTLY" the same spot everytime ( very important ), stalling up the motor exactly the same rpm each time,having the engine at exactly the same tempature each round( harder to do late in the rounds ) keeping up with the air pressure on the rear slicks and not changing it in eliminations much if any from what you dialed your car in time trials, a properly tuned engine and properly jetted carb are also important factors.
( CARB TUNING NOTE )
I like to go on the lean side a bit on my carb (we race nights) so the car doest pick up much when it cools down at night. A rich mixture will drive you crazy trying to dial in right cause the car keeps picking up numbers every round as the cooler more dense air makes more power.
Sorry for the book just trying to help.


Goodluck,
><Charles

olds48 01-18-2008 11:30 PM

The more "books" the better.I've been to the track alot,but never actually raced yet.Any info at all is a great help to me

olds48 01-21-2008 09:47 AM

Is there any advantage to port matching my exhaust ports?I built a set of fenderwell headers for my car,and am sure they will be on there for years to come.

us7race 01-21-2008 10:13 AM

Everything like that helps power when done properly..
I have heard people say your crazy not too..basically free HP..

curtisreed 01-21-2008 11:46 AM

Hey Olds48,

Go over here and do some searching for your questions. You would be amazed at some of the knowledge that is on this forum.

http://speedtalk.com/forum/index.php

Curtis

olds48 01-21-2008 01:41 PM

Thanks doorracer,I'll check it out.BTW my names Eric.Easier than stretching up for those number keys

poncholvr 01-29-2008 04:47 AM


Originally Posted by olds48
Really?Whats the reason for that?

i 2nd this question
the faster in- the faster out--- it needs to flow-
try a set of screen style gaskets (reed style)
they will help separate the fuel into air better- instead of using the rough intake,
if fuel doesn't atomize you might as well just (dump) gas in it
thus - fuel injection was born


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