lol. have you read anything in his build thread......if you know turbos 6262 should ring a bell. he wanted to run that with a stock motor lol........ thats all i will say

and to the second point....theres a reason companies like ferrea and supertech are around. the stock components arent the worse but when you get into some serious boost an upgraded valvetrain is always needed. hell if i someone used stock valves on my camaro and i found out it would be the builders ass when the motor blows up.

 

The LNF is brand new, how do you know they love a 5 angle, 1mm larger, valve job??

Sorry, but i don't know if I'm going to take your word for it.

 

Not to mention, Inconel is much better than sodium filled steel valves.

K thx bai.

Brand new 3 years ago. Close, but not quite brand new. Believe it or not, there have been people building these motors since before they were even released (GASP! GMPP).

Umm, because I know of a couple builds the shop I work for, and a few other LNF builers (GMPP being one of them) that have 5 angle, 1mm larger valve jobs. The heads are our biggest restriction. A port and polish only goes so far, when you are looking to make over about 400whp, you have to do everything to make the head flow more, and it really relieves the stress on the head, and relieves the restriction of our head.

No, I don't have the actual dyno proof, but yes, I have seen it before, and the prrof is in the pudding brotha!

 

the shop where i work on my car is almost finished up with their lnf head project. this is where mkriebs is talking about aswell. from what ive seen so far it proves your point wrong. when they get on the board as a vendor you'll see the results.

 

The way I look at it, if we can pick up 30whp on a decent hand port and polish, the next trouble spot we will have is the valves. Anytime you add volume, you will gain power. Sure, we might not see big gains on the stock turbo, with the larger valves, but we aren't talking anemic little K04's in this thread, we're talking about the big boys now. Anything over stock will benefit from the improved airflow.

 

No offense matt because i like you, but i'm not taking the word from a single shop out of the blue that has yet to actually produce a long term daily driven LNF, and can prove side by side with evidence that what they're doing is the end all be all.

As far as i'm concerned there are only about 2 people that can say with certainty what makes an LSJ tick, and they're still learning.

Volume does not always equal power. If i am proven wrong so be it, i just don't like when someone says, this single upgrade is the golden ticket.

and 3 years is incredibly new.

 

idk which matt that was directed twords lol. but if he then no worries man. understand your attesting a point and thats all good. thats how things improve and get better by everyone testing eachothers knowledge. ill have the proof soon enough. im saving up some extra cash to do the head. its not cheap otherwise your proof would be layed out in front of you. they have been in the lnf scene for quite a bit just not on the cobalt hhr platform. mostly solstice and sky. cobalt parts are in the works on my car so you'll see shortly when they become a vendor.

 

Confused what you're referring to.

Stock LNF valves are sodium filled inconel. (ftw)

 

I wasn't aware we were talking about daily driven motors here? Last time I checked, a sleeved, forged lower end motor with a complete head job wasn't necessarily considered a daily driver, but more of a race motor. Either way, Werks has been in the LNF game since day 1 with the GXP Solstice. Thats just as long as anyone else with the exception of GMPP.

That said, GMPP was the first to build the LNF to substantial power levels, and has the most R&D in the motor, thus I will use them as a main example. They have proven the head jobs make a difference. If you want, look up a guy on the Solstice forums, and ask him. He is using a GMPP build motor in his Solstice. Its still for a rather 'mild' build, and I am not sure of the specs on it. I say 'mild' build, in comparison to what his turbo choice is, and what Cardelino's turbo choice is.

I am not entirely certain how you think more volume doesn't make more power. I somewhat can see the point in a poor port/polish job that disrupts laminar airflow. And I understand that you want to keep the flow of the head efficient, while maintaining good velocity. BUT, you also have to understand we aren't talking about your stock turbo, or TVS blown motors here. We are talking about turbos that push 70-80lbs/min, and support 700-800hp to the ground. We need to make these cars eat as much air as possible. The velocity will be there, and the air will be there, guaranteed.

I would not be so bold to make a statement that a +1mm valve job would make a difference on a stock turbo car. The stock turbo wouldn't have the breath to push the air with enough velocity, and it would be a hindrance to performance.

Yeah, there isn't a whole lot of proof that the valve jobs make a substantial difference, but the proof is there. The biggest proof I have is GMPP. Plus, beyond that are the numbers I have seen from not only plain old port/polish jobs, but also minor, and major valve jobs. And then, lastly, the logic behind it all. Obviously as airflow increases, the need for more volume increases.

Its just like the analogy of boost, using straws. You can't suck the same amount of fluid through a small straw, in the same amount of time, with the same amount of pressure, as you can a larger straw. That said, you can suck the same amount of fluid through a larger straw, at a lesser pressure than a smaller straw. Boost, believe it or not, is NOT our friend in building a motor, boost is restriction that happens between the discharge of the turbo, and the combustion chamber. This includes the head, charge pipes, intercooler, etc... When we are looking at an engine thats built to support 800whp, we need a damn efficient head, thats not going to hinder our flow.

Like i said before, this is ONLY for the turbos I know Cardelino is considering, which is the ONLY reason I asked it in here. It would be a plain waste of money for me to go out, on my stock turbo and do all this, and I would likely lose a crap ton of power up top. Hope this makes sense, and was somewhat educational.

Will, I know you know your stuff, and its cool that you're questioning, because we all learn that way, but sometimes, its best to take someone's word when they have the experience. But, take the proof I have attempted to provide, as you may, and there will be alot more proof hitting the market in the next year.

Also, I will say this, the LNF market has been rather slow. We are finally figuring out what makes these motors go boom, and we are finally getting people to build their motors. There is literally less Sol/Sky guys building their motor, than I have fingers on one hand, and the majority of them are building the motor for reliability's sake. The engine is rather far from new. the majority of the components were engineered alongside the LSJ, and the LE5. The technology from both are present in the LNF, except that the LNF gets a **** blocking DI system, that ruins your day when you wanna make gobs of power. Besides that, all principles of a normal motor still stand.

 

Shape is more important than volume. Volume could be added to a port and it can hurt the flow. All of our porting development is measured on a flow bench, because it is the flow that is the most important factor. On the turbo and supercharged engine porting the exhaust is way more important that porting the inlet. On the inlet side you have the brute force of the turbo or supercharger pushing the air in but on the exhaust you have to rely on the ability of the port and exhaust to flow. If you can't get the air out efficiently you will be limited on how much air you can get in.

mkriebs is correct in that when you have a polished port that you have maximized flow the next restriction is the valve openings. The quick way to help this is with higher lift. if you have not run out of lift, then adding 1mm bigger diameter valves is a lot of work to get the same results you could get by increasing the lift. This works for both inlet and exhaust.

 

I'm 100% with ls1fbody. And btw mrkriebs - the stock valves are sodium filled inconel valves.

The further you deviate from a stock motor, the more likely something is going to go wrong. And for what? Is the OP really going to slap on a 66 lb/min turbo (GT35 sized)? If it's GT30 or under, there are unjustified costs. This is for someone that is apparently putting this all on credit, since he said before that he couldn't afford to rebuild the motor, and was going to sell the car with a busted motor. He's not gonna shell out for a big turbo setup.

And good god, I still can't believe he's being advised to do all of this, yet there may have been valve to piston contact, and the stock valves are going to get re-used.

 

I realized this the second after I wrote that, just too lazy to edit out my post.

You really need to read before you speak. the motor the OP is working on will be the R&D engine for treadstone. The owner of that motor is speaking of putting on a big turbo, anywhere from a PTE5557, to a PTE6262. The 5557 is a GT35 framed, 55mm turbo, with enough flow to support 535hp, the 6262 is a GT42 framed (i believe) 62mm turbo with enough flow to support around 700hp.

 

You guys suck. I went and bought a 35mm socket this morning, had to hammer it on the nuts. I gotta remember not to listen to people on the internet. It's a 36mm socket needed.

 

there is more to this blowing through the straw, for instance, whats on the other side of the straw. Bigger valves only mean that there is less area around the valve inside the bore. a stock size that is un shrouded will flow better than one that is oversized and isn't.

 

C'mon, port/bowl shape doesn't matter at all. Just put bigger valves in it and increase port volume. That's all you need to port heads and make 40 more hp.


@ this thread.

 

just hog them ports out, they will flow like some 11 degree big chiefs

 

After reading this entire thread I get to this part.. made my day ..

 

Yeah, I was pissed. I borrowed a 36mm yesterday, but it was too short (regular socket, not an axle one). Listened to these idiots, so I went out this morning and got the wrong damn socket... One day i'll learn.

 

Hmm, I swear a 35mm worked on my car, thanks for calling me an idiot, really makes me feel good. Maybe do your own ******* research than taking the advice of people on the internet. Maybe your the idiot? Gimme a break dude.

 

Calm down.

Like I said, my fault for listening to people on here. I know better.

 

Now... to quote Mr Bill Duncan, the engineer in charge of these engines, just a few posts up from yours:
"mkriebs is correct in that when you have a polished port that you have maximized flow the next restriction is the valve openings. The quick way to help this is with higher lift. if you have not run out of lift, then adding 1mm bigger diameter valves is a lot of work to get the same results you could get by increasing the lift. This works for both inlet and exhaust. "

Now, am I saying that you would leave the stock port size and shape? No. You guys are ridiculous. I am sure you have both built LNFs that make 600+ hp, that have fully built heads, right? Gimme a break, and quit being douche bag know it alls about everything.

Essentially, since we can't run cams, the next step would be the valves. So, good luck on your stock valves, that are likely bent.

 

dude you get way too defensive about everything. get the sand out of your vagina

 

In all seriousness man you can't get mad at them you didn't do your due diligence, like the saying want it done right do it yourself.

 

Yep, definitely have sand in my Vagina. Its ridiculous talking to people on this site, because you can never make a point. Guess it all depends on the engine's owners end goals. By the way it looks (his turbo selection), he has some very lofty goals, that I don't see happening without a very built head. Thats all I was saying, and then i get criticized for saying that?

Card's turbo selection, seems to point that he is shooting north of 500whp, and the fact he is sleeving the motor, and building everything now, leads me to believe he might have even higher goals down the road. To get to even 500, he is going to need, at a minimum, a pretty damn good port and polish. To get over 600 (which, he may not be wanting, maybe I should have clarified and asked exactly what his goals are), he is going to need a set of yet non existent cams, or a valve job. So, there are his options, and since no one wants to make cams for the LNF, I would say the valve job is his only choice.

 

I was being sarcastic.

Your best bet is to ignore me. You take the internet way to seriously. I don't.

I'm not mad at anyone, i'm pissed because I knew it was 36mm, but people on here said it's a 35, so I figured, they own the car, they should know what the **** they are talking about. Again, I was mistaken. I looked at it and realized it was 36mm. These guys swear that they've taken them off and it's a 35. Nut measures about 35.4mm. you tell me.

Like I said, my fault. I made it work anyway, it's done. I'll go get another axle socket before i re-install, just adds to my collection anyway.

Take it up with him. Why are you arguing with me? I'm doing what he asked me to, found more severe damage that originally guessed, so I gave him options and this is what he chose. Honestly not my problem one way or the other, I want to help him out as best I can, but if he doesn't have the money to spend, it's not really an option. I'd love to do a fully built LNF for someone, but realistically, there aren't many people in this market, driving a $20,000 economy car, that will spend $10,000 on a motor built the right way. That's just life.