Ported Head Results

Goinbyyabig

Goinbyyabig

Free Thinker, Innovator
Joined
Apr 12, 2009
Messages
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I thought I'd share my findings after installing a sidedraft intake from ZZ Fab along with my (non professional) porting job and bowl work. With no other parts or tuning changes, my boost is down substansially; I could previously make 50 PSI with little effort, letting off to save the stock gasket and bolt combo. Now, 40-42 lbs is all I can make, holding it wide open as far as I can. The other good news is the EGT's used to climb into the 1400's really easy, and I would lift to make sure it would live, now I can't get to 1200 if I try; very close, but not quite. Also, the truck used to smoke at WOT and now it clears up completely, must be time for more fuel:rockwoot:

Anyways, in my humble opinion, this is a very worthwhile mod, certainly not cheap, I did everything but machine work and the valve job myself, and still have almost 2500 invested, not counting the second head I bought to continue driving the truck while the head was completed. But does it make a difference? Hell yeah!!! Can't wait to get that 4508r installed now, then the killer bee.

Just for the record, the truck is an 06, Smarty Revo, 90 hp. wicked tips,ported ATS 2nd gen. manifold, Garret GT3782/88r hybrid, Arson 3 DIY kit, dual walbro 392's, boost pressure referenced Aeromotive regulator,and a few other little things. I have the GT4508r and the cam, just looking to do one thing at a time so I know what mods made the biggest difference. Thoughts?
 
Sounds like it helped alot.. Did you notice any increase in spool up? Pics of the port job would nice to see..
 
Great info! Are you going to run the 4508r with the 3788 in a twin configuration, or as a single?

--Eric
 
The GT4508r will be the primary in a set of twins; I absolutely can't wait!! The porting was done in several installments of time, I would guess an honest 12 to 15 hours of hand porting, plus valve job, etc. I just followed the advice offered by greg at ZZ Fabrication, seems I did allright.

As far as spool up time, I don't notice any difference either way, but it spools really fast still, from right off idle, just like before the head work. Several people said the bottom end would suffer, and spool up would be slower, if so, I can't tell at all. I also went to a .020" thicker head gasket, if anyone's interested.
 
What all did you have done at this point? I've been wanting to do head work, but I wanted to save up and do O-rings, P&P, and bigger valves all at once.
 
less than $500 in parts. Aaron Darbee on here machined the pieces for me and i welded the tube myself. luckily you can see the welds. I also lost 5 psi of boost easily. $1300 in head work.
 

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I agree with the head port job. A local guy hooked me up with mine and it was the 1st diesel he had done. I hit the dyno about a month after installation and made 405/932 with many stock parts. (See my signature) If you have the head off I believe it’s worth the time and money.
 
I went a different route

I went with Extrude Hone. Yes they can EH almost anything w/ measured results. I got 17%-19% increase with a differential of 2% cylinder to cylinder with their process. I feel like it was a good investment to increase my flow substanially. With this process you need in install NEW valve seats following the process. That is NOT expensive however. I also had my intake horn and exh manifold done too at the same time.

Talk about slick,... it feels like teflon with oil on it,... slick!

Just my $.02 but I got concerned when I hear guys get on the forums and talk about hogging out this and that on these heads. I achieved match cylinder flow with this process and I have measurable results from a Superflo Flo Bench.

Would I do it again,.. you betcha!
 
Just wondering. when you port your head you have less boost..Does that mean you don't have to worry about studs as soon?
 
if your going as far to port the head, and have it off the truck for that long you shouldnt have think about that.
 
When people say "you need head studs above 50 lbs. of boost" the reality is the cylinder pressure is going up also. This is what the head gasket is sealing, not boost, but it's much easier to discuss as "boost levels". Actually, boost is just restriction of airflow into an engine, and can be effected by many things, head design, cam profile, exhaust restriction, compression ratio, etc. The answer I would give is if you have the head off for porting or other performance related work, it should get studs, period. If it was off for a repair, and no mods were ever anticipated, then leave the stockers in there. If money is the main motivation, put in the 400 dollar ARP's, not the 625's. Also, it's a lot of work to do it twice, so choose carefully, adding time to clean the oil out of the cooling system, and multiple oil changes to clean out the crankcase from a blown gasket also have their costs. It's up to you!
 
Ok.. I was asking from the stand point of..if the boost isn't as high I wouldn't think the cylinder pressure would be as high therefor not need them as bad as you would with more boost
 
R.C.inc. said:
Just wondering. when you port your head you have less boost..Does that mean you don't have to worry about studs as soon?
Click to expand...

I'm thinking - more air in - more are out .
There is going to be more air in the cylinder , more cylinder pressure
doug
 
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