Syndicate

just wondering if it is worth the time to port & polish the stock intake instead of buyin a GDP intake. Being that Im tight on cash and already have the tools to do this myself I wonder if its worth it. For those of you familiar with what the look like inside could they be cleaned up enough to make a difference?

t-boe

Well if you have the tools and the know how I say do it. I don't know if it would help, but you could start a new trend if it does. Free mods are cool.

Syndicate

Im just wondering if its worth the time to take it off. Is there enough meat there to make any real improvements. I would do it just to see as a winter project. really I know it cant hurt but is it a total waste of time?

t-boe

Even if you see just a 50* egt reduction and that was it, it might be worth it. Depends on how much time it takes. It might help since it won't have any rough edges in there.

dbossdiesel

I'd say, why the hell not? Smooth is allways better when it comes to air flow! Let us know how it turns out!

Syndicate

looks like there is enough meat to port it out a fair bit.

t-boe

Even if you don't make it any bigger, smoothing out the airflow should help.

Syndicate

I'll try it when I get some time. Gotta finish the basement suite first. Ill post some seat of the pants dyno results when its done with some pics.

it looks to me from the pic I have off the swanker intake site that you could gain approx 1/4'' between the mounting bolts. That would open up the airway a ton not to mention all the blending you can do in there to smooth out the flow.If its good for a touch faster spool and 50* lower max egts id say its well worth it. Maybe it will help the milage a touch too.

CReed

First off are you asking about porting and polishing the stock intake horn or the actuall intake side of the cylinder head?
.
First if your refering to the intake horn your wasting your time porting it get a gdp or hellman intake horn they are great that stocker is junk and restrictive.

If you are talking about the head the intake side you have to have the intake rail machined off you can do under valves without doing this however.
Third ZZ fabrication has a alluminum intake rail replacemeth that bolts back up to the side of the head after that old castiron piece is machined off and porting is done
Forth their is not mod need to do the exhaust side.

Now i have heard off people claiming power gains but really i doubt it.
I have heard of people with dropped egts which is a given.
I have also heard from a guy that recently made 1100hp with his common rail claim that he had a ported and polished head with zz fabrication rail say that he actually lost power with it. O and buy the way he is still running stock cam and pistons. Just valve springs and head studs with lots of #2 and NX.

Just my two cents I have a friend who is great at porting and polishing heads lots of gasser experience and I think we will be working on a few of these soon.

bob4x4

The stock 3rd gen will not gain enough to make it worthwhile.The restriction is severe where the 2 outer hold down bolts are.You won't be able to repair that.What I saw was about a 5cfm gain with a completely smooth intake vs one with a normal cast finish..........not enough to see any real gain.

Bob

Syndicate

thx BOB thats what I was looking for. Someone who had actualy done it and tested the results.

abc4yew

Concerning the head...While machining the intake trough off enables you to get better access....I found a mini die grinder with 3 inch carbine and 2 inch stone tips got right in there....I took off a huge amount....making the passage more uniform in diameter to the intake holes.

While the intake horn restriction seems like alot.... measure the cross sectional area of the turbo outlet and compare....usually way bigger unless you are running a K31/A5K. I ported and polished my head on the exhaust and intake. I focused on the outer 4 cylinders as these were farthest away from the intake inlet and the exhaust outlet....but I took a chunk out of them all. The stock intake horn is not restrictive as much as it is disruptive. That said the whole intake is just as disruptive.

I ran my twins using a Super B as the top turbo....therefore the total area of the turbo outlet was about TTx4cm=12.6cmsq (I just measured it as it is sitting beside me in my office (sad, I know)...the intake horn restriction is 8cm x 4.5 cm or 36cmsq (my spare also sadly in my office) ....the intercooler pipe is TT x 3.25 x3.25=33.2cmsq. I ran the twinturbos normally up to 75psi...using the unmodified (except for 2 water, and 2 boost fittings).

To put this all in perspective the outlet of the head....the exhaust ports are 13cmsq each.....so you inject 33cmsq of cross sectional air at the inlet...explode it with an overabundance of diesel...raise the temperature from 300 to 1400 degrees...keep the same pressure (if drive pressure = intake pressure) and it is forced out of the head through 26cmsq of exhaust hole. Don't get me started on 4 partially opened valve diameters....

Sooooo, you'd make more difference painting the outside than you ever would porting the inside of the intake (actually I did lightly sand off some casting blobs...they just bugged me)....sorry for the long answer.ks

mj007

Swap the 3rd gen. (restrictive) intake horn for 2nd gen. piece

XLR8R

Removing any material from the inside of the airhorn only provides cosmetic benefits....

yes - I ground mine!