porting the head

ok i know on gas cars it does make a difference. the porting king of montreal tells me i can get a good 20-30 whp from porting it. now i dont know if i can believe this. what do people with experiance think??? im not sure where im going with this car yet but its starting to have a alot of milage on it. so might consider a rebuild

he wants 1000$ for cleaning and porting. what do u guys think

BlakGolf said:

ok i know on gas cars it does make a difference. the porting king of montreal tells me i can get a good 20-30 whp from porting it. now i dont know if i can believe this. what do people with experiance think??? im not sure where im going with this car yet but its starting to have a alot of milage on it. so might consider a rebuild

he wants 1000$ for cleaning and porting. what do u guys think

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20-30whp?
Well,compared to a nearly completely clogged intake maybe

Just clean and rebuild the head,gasket matching and removing some unneccesary casting might be ok though.

Make sure the valvestem tip height is correct,so the hydro lifters are working as they are supposed to

well the thing is if a random person had told me 20-30 i wouldnt have believed him at all. but tom is one of the big names in head porting. he has many nhra race cars under his belt. and has been doing this for quite some time. its very rare for him to make fake clames. he even told me not to even waste my time with gasket matching since its only 4% of a heads flow.

head porting is a art, i wouldnt let anyone touch my car except him. maybe i could work out a deal with him. i dont know yet

I sure would like to see the flow numbers before and after a $1000 porting job.

That 1000 seems a tad hight... My head is ported by 68corvette and I'm sure he can give us some before and after numbers. But to gain 30 hp you would need to be pretty overfueled darn and you cant get that much through R520s to get that much out of head porting...

how much did u gain from porting? im ganna try to work out something with tom.

20-30 hp will not happen ON ITS OWN. The extra air flow might let you increase fuel delivery to match and *that* will find some power. There's something to be found, no question, the stock ports are just rough cast, the priority was on emissions (swirl) while being cheap to make. Whether there is that much to be found, is a darn good question that I sure don't know the answer to.

You will gain nothing from porting (alone)
The ONLY way to add HP in a diesel is to add fuel. If your buddy works on mostly gassers, the same principles do not apply. For example, he will probably take one look at the swirl nub and want to remove it as an "unneccesary flow restriction". This will LOSE you HP.
For example, you can gage the HP in a gasser simply by measuring the mass air flow. Increase the mass air, and you increase power in a gasser. It is very simple. Maybe this guy is assuming the same holds true for a diesel. It does not.
That said, if you increase the air flow, with all other things equal, you improve the engine's *ability to support* adding more fuel and therefore power (fuel is power in a diesel) with lower EGT and smoke. BUT YOU NEED TO ADD THE FUEL, either through bigger injectors or different tuning or both. This is not the same as when a gasser's injectors run out of flow capability to support increased airflow, because diesels do not require a fixed air/fuel ratio.

Another way to think of this: Gassers throttle air, Diesels throttle fuel.

yah tom mostly does hondas and vw and muscle cars. the thing is noone in town has really pushed the limits. anyways i think im ganna forget about it and just clean up the head and put it back togheter and call it a day. i can get bigger pistons for that price plus machining anyways.

i dont wanna dish out 1000$ only to find out that he ****ed up the head instead of making it better

Good plan ... If someone with gasser-think removes the swirl-generating part of the casting as "too much restriction", thus resulting in no swirl, the engine will make smoke rather than power ...

For $1000 you could replace your VNT15 with a 17, and have money left over for injectors. Add $300 for programming and you'll gain WAY more than 30hp.

thats not the point of this thread i knew that already. im either getting a gt 20 or vnt 20 not sure yet

I would say go with a vnt2056v or vnt2260v with r520's and 11mm pump....if you go with the later turbo i'd also do a 130pd bottom end.

I saw no actualy HP gains; although my car isn't exactly an ideal test bed. My head was extensively ported by the local guru and cost about the same as your suggestiong. The biggest change I did see was going from heavy black smoke at WOT to a gray/brown haze. I used to be able to bury the car behind me in bad assed black smoke but now there's hardly anything. Porting chertainly changed the air flow.

I suspect your friend may not be your friend when it comes to a porting job. Sure it'll cl;ean up some smoke and it clearly improved the flow of the head on the flow bench, but 20-30 HP is bull. Take a look on my gallery if you want to see what the porting job can look like. It's already been recommended that you could put you money elsewhere and do better.

I could say the same about my ecu against an A4 A5 ecu being less tunable...but get someone who knows what there doing with it and it will produce as much if not more power than so called newer ecu units...everything being equal (mods etc).

I've raced against a chipped Seat Leon 160hp and made him feel silly plus other cars which are known to be faster.........why do you think this is possible!!....imo its all the little mods which some don't think do much but collectively they do.......i would back it against any 1.9L tdi or 2.0L tdi running on diesel and 95% of tdi's who don't just use it.

i thought the pd 130 bottem rods didnt fit the my block. im preatty sure ill get the oversized pistons tho. the car is starting to get old. im gettting a fresh paint on the front end as soon as its out of the impound (**** the police btw) and i got some nice kw v1 for it to. might aswell keep it a few more years.

Sootman said:

I saw no actualy HP gains; although my car isn't exactly an ideal test bed. My head was extensively ported by the local guru and cost about the same as your suggestiong. The biggest change I did see was going from heavy black smoke at WOT to a gray/brown haze. I used to be able to bury the car behind me in bad assed black smoke but now there's hardly anything. Porting chertainly changed the air flow.

I suspect your friend may not be your friend when it comes to a porting job. Sure it'll cl;ean up some smoke and it clearly improved the flow of the head on the flow bench, but 20-30 HP is bull. Take a look on my gallery if you want to see what the porting job can look like. It's already been recommended that you could put you money elsewhere and do better.

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i told him the same thing, hes probably thinking of gas cars. cuz we can easaly get that kind of gains by porting a honda or vw gasser head

BlakGolf said:

i thought the pd 130 bottem rods didnt fit the my block. im preatty sure ill get the oversized pistons tho. the car is starting to get old. im gettting a fresh paint on the front end as soon as its out of the impound (**** the police btw) and i got some nice kw v1 for it to. might aswell keep it a few more years.

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The whole bottom end!...not just the rods.

even the crank?????? its preatty imposible to find a pd 130 block here btw. so if u have a parts list with part # it would be apreciated

Pm StingRay......he'll ship you what you want/need......(yes) just change over the pd 130's crank sprocket with ve job done......and you may as well use apr/race-ware head studs.........where have you been don't you read these threads/posts!!

to be quite honest i didnt think i was ganna do all this with this car. i was planning to get a g35 coupe this summer. but things turned out a other way. i didnt really pay attention to all that stuff, since i thought it was totaly useless for my car. i think im ganna try to get some aftermarket rods and pistons instead. if i can get 10 people involved we can get some really solid manley rods that will be able to take all the beating u trow at them.

KERMA said:

You will gain nothing from porting (alone)
The ONLY way to add HP in a diesel is to add fuel. If your buddy works on mostly gassers, the same principles do not apply. For example, he will probably take one look at the swirl nub and want to remove it as an "unneccesary flow restriction". This will LOSE you HP.
fuel.

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Can i see a pic of the swirl nub?

There are deffinate gains to be had from porting but like everyone else already said you need to tune it/add more fuel to truly take advantage of the extra flow. Some of the swirl lip can be removed, not quite all of it though, that'll hurt the bottom end, top end you don't really need it at all. Your buddy is right about gasket matching, for the most part you will only see a 2-6% gain, but it varies manufacturer to manufacturer, depending on casting quality etc.

And NO, simply increasing mass flow on gasser is not how you make power porting, velocity is of extreme importance in a gas cylinder head, this is the most common mistake in porting-going to big/increasing mass flow=killing velocity= loss in power.

$1000 in my opinion is high. I've ported a few TDI heads with good results. But if that $1000 is for porting alone and NO rebuilding or assembly reassembly than its pretty high. In comparison I port tdi heads for $500, this is the porting only, no rebuilding or assembly/dissassembly.

tom always takes everything apart to port and puts it all back togheter. i think his website is tkrace.com or something

I still think that a bit high, but if he cleans the head and blasts it helps, dissasembling the head takes about 30 minutes to 1 hour. Same for reassembly.

Gasser is all about volumetric efficiency.

KERMA said:

Gasser is all about volumetric efficiency.

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? All internal combustion engines are all about volumetric effeciency.

onlyn8v said:

Can i see a pic of the swirl nub?

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Can i see a pic of the swirl nub?

I thought the swirl nub is on the top of the piston.. is it not? If not where is it located?

Maybe this is a dumb question but I have to ask.. why do diesels inlet air need to swirl?

I dont think its dumb... The inlet air shouldnt need to swirled because the mixture of fuel and air takes place WITHIN the combustion chamber. Not before like a traditional gas engine. If thats the case in a forced induction engine - to me its air in... air out. Professionals chime in here?