Need some in insight on building a head.

For future im undecided if im going TVS or Turbo. This will be the reason why no Cams are added as I dont know yet.

Got a REAL nice promotion at work, going to have an extra 1800 a month after bills to play with. I plan on paying off my streetbike which I still owe on, and also doing this little project.

Few questions and any help or insight on people who have had the head built in their car is greatly appreciated.

Heres my potential head build.

Port and Polish. - I know the exhaust ports need to be opened up. Is there benefit to porting the rest of the head? Or is it un needed? and WHY

ARP headstuds

Headgasket - ive read oem unit is fine. This true?

Valves - +1mm worth it or not? and again WHY

Neutral Balance shafts - Not head related but while the car is down I was thinking of these to free up a few HP and quicker revs due to not have to spin counter balancing shafts. I know gains will be minimal. Worth it? and again WHY

78lb springs - good insurance

Anything I missed or should consider looking at? I thought about adjustable cam gears but not sure if anyone makes them anymore and would these be worth it? and again WHY?

Thank you for anyone and everyones help.

 

I've seen a 30 percent increase from a slighlty ported head and near 40 with a more aggressive. I've played with the intake and saw no real gains. I can't really comment on the 1mm os, but I've had the opportunity and never taken it.

Stock hg is what I prefer due to reliability and ease to find.

78's are a great idea especially with future plans for cams

as for balance shafts I've been in a car with a delete and vibes were there but I could deal with them, rev time is amazing and I plan on this next time I have it apart

 

Thanks. I like how you answered with personal experience, that's exactly what I'm looking for

 

Head porting, depends on how far you want to go. If you're only going to get a mild port, I really dont see much gain coming from porting the intake, especially if you stay with the blower. If you want to go more extreme I would certainly get both sides ported. Though a good head porter is going to ask you, if its going to be blown or turbo and if its a street/strip, pure strip, street/auto-x, or road race port (most porters wont ask the last 2, though some consider there to be a difference in how you would port it). Another thing to keep in mind is that he may want to know your cam specs as well, or if you dont have the cams yet, you will want to get the flow bench numbers from him so that whoever makes your cam can design it with what your ports are doing in mind.

ARP studs for sure. They should have been studs from the factory, might as well fix their mistake.

I would leave the valve choice to your porter. He is going to know what will work best with the porting he is doing, or should.

Balance shafts, just get rid of them. Cheaper, less rotating mass, same vibes. If you really want to go out you'll get the GMPP balance shaft delete kit that completely removes those sprockets from the chain path.

 

Those have to be pressed in correct?

 

Yeah the balance shaft deletes do. And by pressed I mean tapped in with a mallet and a wooden dowel.

 

A cam is more selected after the flow bench numbers. not the other way around. I ask mods/and future plans, before I do a head for someone. However on cam selection with our little pool of choices it's not much of a subject.

I answer on personal experience because most of my lsj friends run my ported head so feedback is close

 

Ill probably run stock cams with adjustable cams gears

 

That;s only going to move your powerband, I suggest cams zzp has it covered

 

Hmmmm. Powell suggested stock with cams gears.

 

Maybe in a stock head. But you can get the head ported to flow much better than stock at higher lift that the stock cams just dont achieve.

 

powell was referring to built head. i believe when we were talking about it i was suggesting it with a tvs setup.

 

Thats odd. Based on the flow bench results I've seen, race ported heads would basically require a cam with a 0.500 peak lift and fairly long duration (like 260 ish or even 270 depending on some stuff). And do most of your powerband placement by adjusting overlap with adjustable gears.

 

21

 

Dammit not always. If you are building a drag queen or a highway troll yes. But if you are building an auto-x monster you want the blower.

 

That's what they ended up using in the Time Attack SS/SC man.

They started out with GMR cams, and ended up swaping the stockers back in with adjustable cam gears.

John knows what he is talking about.

 

^this.

Ill have to check ced. I think they still offer adjustable cam gears.

 

Yep, they still offer them.

I looked into them to help complete my GMR setup, but Area told me they are a bitch to setup. I may change my mind down the line though, and pick up a set.

 

They are hard to setup with gmr cams or in general?

 

In general.

 

I would think so, considering you have to pull the valve cover to adjust them and you should be adjusting them on the dyno. It could take you all day to get them dialed in. And all day on a dyno round these parts is in the 1000 to 1500 dollar area.

Depending on how they adjust you may be able to get away with making a sacrificial valve cover that has holes drilled in it so you can get to the adjustments and rubber trap door seals. so you just stick the tool through the rubber flaps without needing to pull the VC.

 

Wait toll u see my valve cover .... never seen it done yet

 

turbo 30r pump gas done.

 

haha, keeping tabs?

 

they had to use the adj cam gears on the gmr cams so it would make sense that they would swap them onto a set of stock cams and zero them out you will not gain any performance what so ever with adj cam gears on stock cams