Jump to content

Turbo Lq9


Recommended Posts

So I have a Sts turbo on a basically stock lq9 with dynatech headers at the moment. it runs on 6psi, but leans out pretty fast. But know I wont some more power. So I am going to put the boost up at around 12 PSI with a fast intake (102mm). but I am wondering what should I run for the fuel system and what brand and size of injector. Also I am going to put a cam in so i was going to do roller rockers so i have to take the heads off. So I was going to port and polish the heads or should I just get some performance heads and if so should I stick with cathedral port or goto rectangular ports? also what is a good head to run? Also does anyone make a head stud kit for the LQ9. Know well I got the heads off I was thinking It would be a good idea to lower the compression so is there any kind of spacers for the heads or should I just throw some low Compression pistons in. Also If I blow this engine up I would like to be able to change my heads, Intake, Cam, Fuel over to a 406 or 408

 

 

OR

 

Should I just pull the engine out And do it right know and build a 406/408 or something else. My goals are to get low 12 or even hit 11 second.... Eventaully. I want to keep the budget around 10 ish, because I am buying a house in the spring. I will do most of the work myself other then the machining.

 

I am also putting a built 4l80e in right know that is built for over a 1000 hp and I am planning on running a 3200-3400 Cicle D torque converter

 

This is my first High Performance build So any advice, experiences or info is great. The truck is by no means a Daily driver and only sees roads for about 1000 km - 1500 km since we dont have many nice days up here. Thanks for all your help

Edited by GonzoSS (see edit history)
Link to comment
Share on other sites

I started with a sts setup because I had to pass a emission test up in ak. I had nothing but problems with the sts oil pump. As soon as the I/m was pulled up here I built a front mount setup out of my sts setup. It was a lot easier to deal with. My two cents about the sts. I ran one for three years.

Low 12's is pretty easy with forced induction. I know you can do it on the stock bottom end. They are way stronger than everyone thinks. I built my motor because I burned it down three times before I realized that my waste gate was freezing in the cold temperatures up in Alaska. I thought it was my tune.

I think fuel will be your most important part of your build, other than your tune. I built mine with low compression, thinking I would turn it up more. Zippy told me I should be turning mine up around 20psi. I don't think I would drop it down so low if I could do it again. I have yet to go past 13psi because I'm out of fuel. Get a good tuner, talk to them about how much boost you want. Then ask them about what injectors they have tuned before. I went with fuelinjectionconnection injectors. They gave me the injector data sheets so that didn't really matter.

I think you can get your goals on a stock motor, stock 317 heads(with new valve springs), and a good fuel system don't forget a good matched turbo for your goal.

If money is no object, you could go a lot faster. Lol

I've left a lot out. But you can only type so much on a iPhone. Lol

 

-edit for stupid spelling and using tapatalk.

Edited by Aksss (see edit history)
Link to comment
Share on other sites

Well there is so many things you could do. I myself have been through 3 different 6.0 do to cracked pistons. I feel that most of my engine failures were do to my tune. I think these motors in stock form can take 13-14lbs of boost with a good tune. if you can afford it I'd just do a forged bottom end and be done. only reason I say that is because it seems like we always want more power after we have hit our first goal. I started out wanting to run 13.5s and I told myself I'd be happy. then 13.5s weren't enough then I wanted 12.5s. I got 12.5s now I want more. But your limited to how much power that stock bottomed can take. I wish I would have just built a stout bottom end when I broke my first motor.

 

with boost I wouldn't go much more than a .030 bore on your lq9. Im not say the block can't be bored more. I just like a little bit more meat on my cylinder walls. if you go with a 4.030 bore you can either do a 370 or a 408 they both use the same bore to make a 408 its just the stroke.

 

Are you planning on running the STS for along time or are you planning on switching to a front mount. I have heard a lot of issues with the rear mount turbo kits, all mostly to do with oiling issues. but I have a buddy who also ran one for a few years with know issues. he sold the truck and its still running around just fine from what I know,

Link to comment
Share on other sites

I will probably keep the STS kit, for know anyways as I have not had anytrouble. How much around would I be looking at for a froged bottom end. Just not sure what I want to do now, as I have two other Project that I want to get started on. Not sure if I want to drop all the money into this or just do fuel and intake, plus tune and then start on one of my others, since everyone is always bugging me about them. haha.

Link to comment
Share on other sites

Why do you need a different intake? With a pressurized intake it might make a diffrence but the stock truck intake does a good job. I still have it. Probably holding me back a little because of the smaller throttle body. And what intake do you want to go to? Also, are you intercooler?

Link to comment
Share on other sites

If you have other stuff you would rather work on and just want to up the boost and be down. Then i'd just tackle the fuel system and call it done. no need for an intake. they hold there own. I have seen a truck go 9.65 on a stock truck intake.

Link to comment
Share on other sites

Yeah I am intercooled. Would you recommend a different throttle body though?. I just cant make up my mind on what to do... Get this truck done to the nuts, and hold off on my others for a while, or start throwing money into my other projects (I got a 1991 Z28 and a 67 c-10, sitting around). Well Maybe what I will do is take the heads off and see what it looks like internally and if I see anything out of wack, well then do it all; if not, then just do the fuel system, cam, and bump up the boost. Does anyone know if they make a stud kit for the heads?

 

If you don't mind my asking, what are you runnnig in the 1/4 and whats your estimate for HP on your SS? I love that truck. Makes me wish that I had found a blue one.

Edited by GonzoSS (see edit history)
Link to comment
Share on other sites

Why do you need a different intake? With a pressurized intake it might make a diffrence but the stock truck intake does a good job. I still have it. Probably holding me back a little because of the smaller throttle body. And what intake do you want to go to? Also, are you intercooler?

 

I was looking into getting a FAST LXRT intake with a 102mm throttle body. Inless if rectangular ported heads are better then I would have got the FAST LXR 102mm. But if your saying that it would not really be worth the extra money, then I will probably hold off and put the 2 grand to something else.

Link to comment
Share on other sites

The truck has run a best of 12.53 at 108/ but that was 2 years ago. with no weight removed. that was full weight. that was also with the4l60e and a baby converter. I haven't had the truck to the track sense then. I was running 13lbs on a stock lq9 with a 65 wet shot. my tune was a simple mail order so I'm sure the truck had more in it. But I should of had the tune redone. I'll be going with a different tune this time around with more compression and about the same boost. hoping to hit my goal of 11s but more than anything I'd rather the motor to stay together. So if I dont run 11s it wont break my heart. I just want to have fun with the truck and to have it last.

Link to comment
Share on other sites

I think you will Hit 11's by the sounds of thing. You would have probably been low 12's with the set up before you broke. How did your stock heads hold up with that set-up, or do you wish you would have got new heads, or port and Polish the factory ones?

Link to comment
Share on other sites

do you think, with the write tune and good fuel delievery, these engines could handle 15 psi?

I don't think you are going to get a good answer to this. There is probably a few guys on here that could give you an answer to this, but I don't think that to many people have pushed their setups that far stock. 15psi would double the hp of your motor. By the time you get this kinda hp, you have had other failures or bigger upgrades. ie-heads, cams etc. And if you do some of these upgrades you usually do the rotating assembly.

I'm kinda hoping that Zippy or one fo the other boost guru's will chime in here. I'm sure someone has done it. And it probably could be done, (I'm talking out my butt) if the tune is spot on.

You mainly need to figure out your budget(I never did this). That will determine where you go with this project. My truck started out with a sts kit, and has just kept going and going and going....

Link to comment
Share on other sites

I think you will Hit 11's by the sounds of thing. You would have probably been low 12's with the set up before you broke. How did your stock heads hold up with that set-up, or do you wish you would have got new heads, or port and Polish the factory ones?

 

Well the thing is the heads could have been upgraded. but I feel that with a stock bottom I would rather drop the $$$ into the bottom end first. I'd rather have a stout bottom end than a good set of heads. reason being is because its always easier to swap out a set of heads than have to rebuild a bottom end . I can have my stout bottom end for now and then in a weekend swap the heads down the road if Im maxing them out. I will be running my stocker 317 heads for the time being. then I'd like to switch to some TF 235s or something like that. But at that time I'd most likely switch up my intake also. but I will only switch up the heads and intake if I can not hit my goal. I have seen a lot of trucks make great power with a stock set of 317 with a little bit of port work. look at Jon boys truck stock heads besides springs and push rods. Also Jared runs a hand ported set of 317's and make close to 1100hp on a turboed 6.0 370. So with my build I will be skipped heads and see where it takes me. I will be having a valve job and nice set of springs installed. unless I find a good deal on some heads. but the heads I want are $2500.00 :cry: i think money can be spent elsewhere first. I am no engine builder. this is just what I have chosen for my build.

Link to comment
Share on other sites

do you think, with the write tune and good fuel delievery, these engines could handle 15 psi?

as for 15lbs. I have seen a few members run 15lbs on a stock bottom end. I heck run e85 and see where that gets ya. be like ole jon boy a run 20lbs on a stock bottom end. lucky guy. :jester:
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...