Re: 3.9L cylinder head work

From: msnbcnnbcbs@hotmail.com
Date: Sun Apr 01 2007 - 18:10:32 EDT


Hi Bernd,

I keep getting into an argument with the friend of mine, hes telling me I
cannot produce any power with the stock camshaft. He is telling me I need to
rev the engine to 6k (or more) to get any decent power out of it.

My issue is if the cam needs to come out, things start getting prohibitively
expensive. between a new cam, a valvetrain that can handle 55000+ rpms, and the
custom tune, along with all the items i described below, i may be looking at
close to $5,000. My budget was around $3,000. He is telling my upgrades are a
waste of time without a cam swap. Besides, this truck is a daily driver and I
didnt want to do anything too radical.

My idea was to put as much power out using the stock cam as I could. I've seen
stock V6 heads, and they dont look to good. I happen to be near a shop here in
south florida (mesa balancing) that has done some head work for 3.9's in the
past. I was hoping to get a 2nd set of heads, have them worked on, get the 1.7
rockers on, a new set of headers, the superchips tuner (3715, ive used it
before and I got some good butt-dyno feelings from it), new injectors, and
possibly have the intake manifold worked on.

heres the link again:

http://www.hughesengines.com/partDetail.asp?partID=10697&eTypeID=10

if that doesnt work, the part number is HER0814AL-V6. Someone on the list
reccomended this cam. He used it on his V6 build-up, cant remember who it was
though....

In article <46102144.1080205@dodgetrucks.org>, bernd@dodgetrucks.org ("Bernd D.
Ratsch") writes:
>
>
> I don't have any hard numbers from a before and after, but I have
> extensive head work on my 3.9L and it made a world of difference with
> the cam selection. For the stock cam though, there is no need for
> polishing work unless you plan on running either a supercharger or
> alcohol/nitro. You actually want some "tumbling" in the intake
> portion. On the exhaust side...go ahead and polish them if you want.
> Best place to actually polish the heads is in the combustion chamber -
> it control detonation (removes hot spots from high/low casting flash
> spots).
>
> The 1.7's will work really well with the stock cam but don't plan on
> revving the engine past 4800rpm - the stock cam falls flat at about
> 4600rpm...even with the 1.7's.
>
> The stock PCM will be able to compensate for mild cam/head changes...to
> a point. Don't go overboard though with the cam/head porting work
> though - you will need to put it on a dyno to get the PCM tuning done
> right. These generic "custom flashes" are more of a headache than
> they're worth - yes, I deal with those as well at the
> dealership...nothing but problems until we get them on a Dyno and use
> either an AEM or ROE controller to fix their screwups.
>
> I tried to look at the cam link you wrote...but it isn't coming up for me.
>
> - Bernd
>
>
>
> msnbcnnbcbs@hotmail.com wrote:
> > anyone have any numbers on the gains for a port/polish on the heads on a
3.9L,
> > with a stock redline?
> >
> > I'm asking because Im getting my parts list together and would like to
avoid
> > yanking the cam out and having to have the computer reprogrammed. Or can
the
> > computer adjust so long as the cam profile isnt too radical? Im trying to
avoid
> > downtim as the truck is a daily driver and I need to give it some ballz so
I
> > can race it at the track without running 17's and looking stupid :)
> >
> > fyi, its something like this:
> >
> > 2nd new/rebuilt set of heads with port/polish (gonna grab em from ebay and
have
> > them taken to a shop near me that does headwork)
> >
> > 1.7 Rockers (the harland set from summitracing)
> >
> > new set of "long-tube" headers (stock ones will most like not come
off/break)
> >
> > new 19lb/hr injectors (have them, need to install them)
> >
> > new doubler-roller timing chain (have, need to install)
> >
> > superchips tuner 3715 (used to have this, its in the mail)
> >
> > not touching the cam because of computer issues (unless it can adjust)
> > specifically, this one
> > http://www.hughesengines.com/partDetail.asp?partID=10697&eTypeID=10, as I
cant
> > afford the downtime.
> >
> >
> >
> > thanks.
> >
> >
> >
> >
>
>



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