Cylinder heads: Ported vs Stock?

[derrick36]

My ported heads made a hell of a difference. I'm about to try an experimental set shortly and may be much cheaper.

I know you're someone who has tried damn near everything Elite has to offer. Do you mind explaining the differences you've experienced? Is it a matter of overall HP/TRQ, spool up times, top end power down the track, all of the above????

6k is for a whole new set with a valvetrain tho. Just getting your heads ported is right around 2k just so everyone is on the same page...

Damn, that's my bad. Thanks for correcting my error. I wasn't 100% sure how they priced the different options.

 

[White_monster]

Well heads are needed on big turbo trucks cause the turbos push way more air. I did the math and my max powers push 1953cfm's of air. Stock heads flow 160cfm each cylinder do that equals 1300cfm's, I did my math wrong earlier. So right there you have way more air in the system than can be used. The ported heads flow around 260cfm each cylinder and that equals 2080cfm's. So now your able to flow all the air from the turbos thru the heads but again the stock manifold is your bottle neck. It flows about 150cfm on the rear cylinders and about 240 on the front cylinders. A ported manifold gets rid of the restriction to the rear cylinders and makes all cylinders get equal amount of air, think it usually works out to about 240-260cfm each plenom. So if you put heads on the truck but don't do a manifold that flows the same you are not getting max potential from the heads. Hope this clarifies this issue.

 

[derrick36]

Well heads are needed on big turbo trucks cause the turbos push way more air. I did the math and my max powers push 1953cfm's of air. Stock heads flow 160cfm each cylinder do that equals 1300cfm's, I did my math wrong earlier. So right there you have way more air in the system than can be used. The ported heads flow around 260cfm each cylinder and that equals 2080cfm's. So now your able to flow all the air from the turbos thru the heads but again the stock manifold is your bottle neck. It flows about 150cfm on the rear cylinders and about 240 on the front cylinders. A ported manifold gets rid of the restriction to the rear cylinders and makes all cylinders get equal amount of air, think it usually works out to about 240-260cfm each plenom. So if you put heads on the truck but don't do a manifold that flows the same you are not getting max potential from the heads. Hope this clarifies this issue.

Goddamn.

There it is.


Thanks man.

 

[ProjecT 9]

I'm sure its about what the cylinder heads flow stock and what the current turbo's can supply. 1800cfm (if thats correct) is a lot of cfm! If all bottlenecks are taken care of before and after the heads and the stock turbo's reached a point were you didnt make more power per adding lbs of boost then you could look into ported heads. Once you add ported heads you'll loose boost b/c the heads are more efficiant (flowing more air) so then you'll have to add bigger turbo's to get the needed volume of air back.

This is what I know from dealing with forced induction applications on cars. You can only force so much air into the cylinder. Ported or not. When it comes to cost, for most applications minus all out race trucks or guys looking for bragging rights on the dyno. Ported heads dont yeild the power/dollar ratio most like to see.

You have to get rid of all the bottlenecks before/after the heads. Once the heads become the restriction then look into the porting. I know diesels are kinda different but I'm sure the same "recipe" applies. I'd assume more fuel, bigger turbo's would be more beneficial for the average guy. Cost wise.

Setup on my vette made 800 rwhp at 14lbs of boost. (supercharged application) Going to a smaller pulley made more sense to keep making power at my power level then adding a set of ported heads. Its a balacing act. You'll eventually have to add better flowing heads to keep gaining power. But then I'd need a bigger blower. Pulley=$100 bucks compared to porting my existing LS3's or new TFS heads was $1000-3500. Ported heads got me less boost, maybe a little more power compared to adding a smaller pulley and gaining more power. Power/dollar comes into play. I know you cant pulley down a turbo but you get what I'm saying.

All in all I couldnt imagine a set of correctly ported heads to be on the list for the adverage DD wanting to make good power. More of a dyno queen, race application.

Just my $.02


There's really a lot of variables is what I'm trying to say. I dont see it being worth adding ported heads to a stock turbo application. But with aftermarket turbo's...sure.

Now I'm pretty new to diesels so if someone more knowledgeable with diesels see's a discrepancy with anything I said feel free to correct me.

 

[ProjecT 9]

Well heads are needed on big turbo trucks cause the turbos push way more air. I did the math and my max powers push 1953cfm's of air. Stock heads flow 160cfm each cylinder do that equals 1300cfm's, I did my math wrong earlier. So right there you have way more air in the system than can be used. The ported heads flow around 260cfm each cylinder and that equals 2080cfm's. So now your able to flow all the air from the turbos thru the heads but again the stock manifold is your bottle neck. It flows about 150cfm on the rear cylinders and about 240 on the front cylinders. A ported manifold gets rid of the restriction to the rear cylinders and makes all cylinders get equal amount of air, think it usually works out to about 240-260cfm each plenom. So if you put heads on the truck but don't do a manifold that flows the same you are not getting max potential from the heads. Hope this clarifies this issue.

Well put, a lot less wordy then mine. haha

 

[6.0dirtworker]

How much is that giant manifold from elites page in diesel power?

 

[Erikclaw]

How much is that giant manifold from elites page in diesel power?

I am pretty sure you will need a custom turbo application to run it. Stock location doesn't work.

 

[derrick36]

I was under the impression that Elite did not fab that intake, but that it was done elsewhere and used in the build up...

It doesn't really matter though. It appears to be an awesome piece regardless of where it came from.

 

[Jhaddox]

I was under the impression that Elite did not fab that intake, but that it was done elsewhere and used in the build up...

It doesn't really matter though. It appears to be an awesome piece regardless of where it came from.

It's a zz fab that he will only make for elite, so you have to buy it from elite but it's not their product

 

[White_monster]

That manifold from zz fab is great and all but it's not the only way to achieve good flow thru the manifold. Elite recently came out with a new ported manifold and GOGO Diesel has had a ported manifold for awhile now. Both options are pretty much identical and offer the same flow increases. It's your choice who you buy from that's all.

 

[Mavericktkw]

so would a ported manifold with stock heads be worth it? how much cfm do the stock and modified stock turbos move(tow powers/industrial/river city diesel work stock)?

 

[White_monster]

Yes. Manifold is good. No idea what those turbos flow thou.

 

[bigrpowr]

I know you're someone who has tried damn near everything Elite has to offer. Do you mind explaining the differences you've experienced? Is it a matter of overall HP/TRQ, spool up times, top end power down the track, all of the above????




Damn, that's my bad. Thanks for correcting my error. I wasn't 100% sure how they priced the different options.

i cant really say but to make 680 damn near smoke free with a pump and nozzles, and have a truck that drove so cool (egt) .... with great spoolup , i know those heads were working very well. ask anyone who rode in that truck. i will be doing cylinder heads again soon, just trying something a little different this time.

 

[Cobra 19 & 54]

i cant really say but to make 680 damn near smoke free with a pump and nozzles, and have a truck that drove so cool (egt) .... with great spoolup , i know those heads were working very well. ask anyone who rode in that truck. i will be doing cylinder heads again soon, just trying something a little different this time.

You're doing those new cnc cut aluminum ones right? With or without H2O jackets?

 

[forcefed6.4ford]

The ported heads flow around 260cfm each cylinder and that equals 2080cfm's. So now your able to flow all the air from the turbos thru the heads but again the stock manifold is your bottle neck. It flows about 150cfm on the rear cylinders and about 240 on the front cylinders. A ported manifold gets rid of the restriction to the rear cylinders and makes all cylinders get equal amount of air, think it usually works out to about 240-260cfm each plenom. So if you put heads on the truck but don't do a manifold that flows the same you are not getting max potential from the heads. Hope this clarifies this issue.

I wonder if this has something to do with the rear pistons giving out when you see them crack. Unbalanced flow

 

[Cobra 19 & 54]

I wonder if this has something to do with the rear pistons giving out when you see them crack. Unbalanced flow

Do you mean higher in cylinder temps due to more fuel and less air?

 

[forcefed6.4ford]

Possible heat soaking due to less flow. EGTS are an average. I bet they spike pretty good on the back cylinders and stay hot longer due to the restriction. I didnt realize the manifolds were that imbalanced.

 

[Cobra 19 & 54]

Makes sense, I've seen dragsters with individual Pyrometers on each cylinder. I wonder if anyone's done this to one of ours yet?

 

[White_monster]

I wonder if this has something to do with the rear pistons giving out when you see them crack. Unbalanced flow

I'd say it does man. There cylinders are getting huge amounts of fuel and way less air on stock turbos. Even modified turbos have this issue. If you've ever looked inside the stock manifold you'd understand the restrictions.

 

[White_monster]

I wonder if this has something to do with the rear pistons giving out when you see them crack. Unbalanced flow

i cant really say but to make 680 damn near smoke free with a pump and nozzles, and have a truck that drove so cool (egt) .... with great spoolup , i know those heads were working very well. ask anyone who rode in that truck. i will be doing cylinder heads again soon, just trying something a little different this time.

Well the heads do help yes but what brought the egt's down? Well the stock turbos are beyond there thermal efficiency range. What does that mean? Well it means the turbos are not able to produce more boost efficiently. At a certain point the turbos only heat the air up and yes you get more boost but the airs so hot you can't use it affectively. So with stepping up to bigger turbos the compressor map changes and allows for a greater volume of air to move thru the turbo for the same boost pressure as was used on the stock turbos but the air temp after the turbo is at a useable temp. So now with upgraded turbos your moving more air into the engine and are able to inject more fuel than stock cause you have the extra air needed to clean it up. Spool up has to do with the exhaust side of things. Sure you need the exhaust ports of the head if you open the intake side up but ultimately the exhaust housing of the turbo is the reason for a spool up. If you set your gate really loose spool is affected greatly. This subject has an insane amount of variables and information for us to cover.