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G.I.Ceo
12-25-2011, 07:45 PM
So here's the deal. I have bought the turbo headers from another member and I have decided to start piecing together a turbo system but I am not going to cheapen on anything. I am not in a hurry to get this done so this will not be something that's going to be done right away. I would like to try and get it up and running sometime in the summer but I never know how money will go. Also I am thinking of swapping to a 3500 while doing this build.

What I wanted to know should I use 36lb or 42lb fuel injectors? I almost bought a set of 42lb ones today but was not sure if they would work or be worth it. I have heard a lot of people say that 36lb injectors are enough. Also are the 42lb Lucas injectors the ones that are on the 01 SS Camaros?

Below is a decent picture of the headers and I will say they are a lot better in person then they are in the pictures and for what I paid for them I got one hell of a deal. I know that the GA you will say is not worth the time and effort but to me it is. I am not trying to out run people. All I want is something very few people have and know that it was all done by me.
http://i1206.photobucket.com/albums/bb441/GICeo/IMG_20111219_1640381.jpg

HOYS
12-25-2011, 10:40 PM
Oh god you bought those?

zukiracer19
12-25-2011, 10:45 PM
before you even start, check and see if that rear flange is warped for crossover and header. because that will be the biggest pain in the ass if you put it together and you blow out a copper gasket... they aren't cheap... and please, please use copper not that cardboard crap; or aluminum. They will blow out the first time you boost. (from experience) I went through quite a few coppers when I was hitting 15 psi but other then that they hold up pretty good.

I'd go with 36 if you're not going to be going all out. That should be plenty; but if the price is right take the 42s.

G.I.Ceo
12-25-2011, 11:00 PM
Oh god you bought those?Why do you say that? Trust me they are not bad and I have thought about having a brand new set built off of this design. Also I was thinking of replacing everything with V-bands and then having them coated. Like I said for what I paid they were worth it.

before you even start, check and see if that rear flange is warped for crossover and header. because that will be the biggest pain in the ass if you put it together and you blow out a copper gasket... they aren't cheap... and please, please use copper not that cardboard crap; or aluminum. They will blow out the first time you boost. (from experience) I went through quite a few coppers when I was hitting 15 psi but other then that they hold up pretty good.

I'd go with 36 if you're not going to be going all out. That should be plenty; but if the price is right take the 42s.
Yeah I don't use anything but copper for my gaskets.

I could have gotten a set of 8 - 42lb Lucas injectors for $50 + shipping. They were from a very reputable place.

HOYS
12-25-2011, 11:17 PM
I've seen them in person, they are pretty bad.

G.I.Ceo
12-25-2011, 11:40 PM
I've seen them in person, they are pretty bad.

Cosmeticaly yes they dont look good. Like I said I got them cheap and I can always modify them or have a whole new set built. Its a start and the manifolds I didnt know what to do about them and then I stumbled on these. These will save me probably $750 in the long run no matter what I decide to do with them.

HOYS
12-25-2011, 11:56 PM
First things first:

You need a turbo with a V-Band exhaust. You will also have to cut the car to install the turbo like Nick-G did. I think that down pipe hits the fuse box pretty hard too.

G.I.Ceo
12-26-2011, 12:11 AM
First things first:

You need a turbo with a V-Band exhaust. You will also have to cut the car to install the turbo like Nick-G did. I think that down pipe hits the fuse box pretty hard too.

Oh I know I am very aware of what lies in front of me and thats the reason I am not rushing this to make people happy. I put a lot of time and thought into my work plus I dont cut corners. I just wanted these as a building block so I could start somewhere and get a list together of stuff I need and work that needs done.

HOYS
12-26-2011, 01:33 AM
You shouldn't use 36lb injectors. If you looking at 300 HP at the crank without going above 80% duty cycle your going above what the 36lb injectors can handle.

You can find 42.5lb injectors any day on club GP for about 150 bucks. If you want to take the cheap route and start slow, 36lb injectors are a dime a dozen. Keep in mind you need to rewire the injector harness and get the new fuel rail brackets that allow for the taller injectors. IIRC the kit is 35 or so from Milzy.

If it was me, I'd go for 60lb injectors from the start (250 used on ClubGP rather frequently) and never have to worry about hitting 80% duty until 475 crank. It is just one less thing to worry about!)

MAC the KNIFE
12-26-2011, 06:57 AM
^hoys, the guy with a milzy built racing block and 400 whp, is he using 60lbs injectors?

the 36lbs were maxed out a bit before 10lbs of boost and 320 whp. about 390 crank.
i'd go 42lbs for a nice turbo setup at around 10lbs of boost. but it depends on what you want your final hp numbers to be.

AaronGTR
12-26-2011, 07:31 AM
36's are maxed at about 280 whp. If you are planning more than that, I'd go with 42's. Most people won't get to the boost levels needed for 60's, or have the engine and trans mods needed to support that power level, so 60 lb/hr would probably be overkill. For the injector harness you can wire new plugs on, or just swap the whole thing for a '99 harness, and only change the cam sensor lead if needed.

zukiracer19
12-26-2011, 11:17 AM
I'm pretty sure cutting of the car is a given, its probably the most simple part of the entire setup imo. But not everyone needs to go that route; but Get a intercooler that has in/out ic piping the same side(driver side) and run them both up through where you cut them out and try to make them as straight as possible, less restriction the better. as for fusebox; that was my dilemma... If you can try to fit a 3" DP but im telling you now i had barley any room with todds setup. Vband turbo back is your easiest route; but if you can make everything vband.

zukiracer19
12-26-2011, 11:27 AM
cutting wheel does the job fine!

http://a4.ec-images.myspacecdn.com/images02/4/ba44ac75fa004752afd1f06160e3a5ab/l.jpg

zukiracer19
12-26-2011, 11:31 AM
Also I made a heat shield for the wiring harness/trans because i had issues with the heat.

http://a1.ec-images.myspacecdn.com/images02/134/fbde98361ff0486abdcd9680383fcd21/l.jpg

HOYS
12-26-2011, 09:13 PM
^hoys, the guy with a milzy built racing block and 400 whp, is he using 60lbs injectors?

the 36lbs were maxed out a bit before 10lbs of boost and 320 whp. about 390 crank.
i'd go 42lbs for a nice turbo setup at around 10lbs of boost. but it depends on what you want your final hp numbers to be.

Yeah, he has 60lb/h injectors.

If you have the funds to buy the 60lb/h injectors it gives you just one less thing to worry about. You won't get anywhere near static and you will have a low duty cycle resulting in a longer life for the injector.

Overkill? Yeah probably. But 100 more dollars for a part you almost will never have to replace...I personally would go that route.

eckoxl
12-26-2011, 11:53 PM
i have 42.5. :D

slw240sx
12-27-2011, 11:09 AM
so heres the deal. leave the headers as is, do not waste any money putting Vbands on those. i wont do it for you either, thats just a heads up. The 3bolt flanges fit together good enough. that down pipe,throw it away and get a 2.5" one made up once you get the kit on and ready to run. 3" will not really fit well with out moving a lot of stuff and modifying **** around it. 2.5 is all you will need any how, my shop has done 400hp on 2.5" down pipe and exhaust its plenty. but what ever is of that down pipe its junk toss it. that crossover has no provision for a wastegate so you can either add one, or get a internally gated turbo. or get a turbo that has a port on the exhaust housing for the wastegate and a 5 bolt flange that has the hole next to the 2.5" outlet for the wastegate. dont listen to these guys about getting a Vbanded turbo, save the money and use it to buy a wastegate. Vbanded turbo is not that much faster or easier to work with. They dont know , i do..... any thing anyone here gives you as far as advice take with a grain of salt because of the few that are giving it only one or two of us actually has a clue and or hands on experience. Zukiracer doesnt even count as hands on because dude is a moron...


blah i just got interupted by phone email, broken iphone problems and everything else as a business owner returning from a christmas weekends where everyone decided to buy off our ebay store. ill be back in this thread to finish my ideas of how to keep this build cheap but decent.

zukiracer19
12-27-2011, 11:21 AM
I find 3 bolt flange header/crossover setup to be fine; But vband exhaust side/dp is so much easier to work with... jus sayin... But my dp was a 3 peice.

G.I.Ceo
12-27-2011, 03:40 PM
i have 42.5. :D
So whats the difference between 42lb and 42.5lb?
so heres the deal. leave the headers as is, do not waste any money putting Vbands on those. i wont do it for you either, thats just a heads up. The 3bolt flanges fit together good enough. that down pipe,throw it away and get a 2.5" one made up once you get the kit on and ready to run. 3" will not really fit well with out moving a lot of stuff and modifying **** around it. 2.5 is all you will need any how, my shop has done 400hp on 2.5" down pipe and exhaust its plenty. but what ever is of that down pipe its junk toss it. that crossover has no provision for a wastegate so you can either add one, or get a internally gated turbo. or get a turbo that has a port on the exhaust housing for the wastegate and a 5 bolt flange that has the hole next to the 2.5" outlet for the wastegate. dont listen to these guys about getting a Vbanded turbo, save the money and use it to buy a wastegate. Vbanded turbo is not that much faster or easier to work with. They dont know , i do..... any thing anyone here gives you as far as advice take with a grain of salt because of the few that are giving it only one or two of us actually has a clue and or hands on experience. Zukiracer doesnt even count as hands on because dude is a moron...


blah i just got interupted by phone email, broken iphone problems and everything else as a business owner returning from a christmas weekends where everyone decided to buy off our ebay store. ill be back in this thread to finish my ideas of how to keep this build cheap but decent.

I was thinking of getting a turbo with a internal waste gate but I know it would be easy to add one if I needed to. I'm not sure how the previous owner installed a waste gate on this setup.

I will definitely take you up on using a 2.5" down pipe so I don't have to screw around with stuff I don't need to.

eckoxl
12-27-2011, 03:42 PM
They are the same thing.

G.I.Ceo
12-27-2011, 03:56 PM
They are the same thing.

Thought so. So where did you get yours from?

eckoxl
12-27-2011, 04:25 PM
zzp.

HOYS
12-27-2011, 10:34 PM
http://shop.zzperformance.com/store/p/112-42-5-Lucas-Injectors.aspx

42.5's

http://shop.zzperformance.com/store/p/111-65-Mototron-Injectors.aspx

60's

60's are like 10 dollars more...again... why not?

MAC the KNIFE
12-28-2011, 03:43 AM
^ you act like theres nothing wrong with going way too big on injectors. too big can be a problem iirc. i'm almost stock so should i go ahead and do the 60lbs anyways b/c of my CAI?

when you get too big of an injector it sprays for such a short amount of time and sprays so furiously that fuel can puddle instead of atomizing.

slw240sx
12-28-2011, 10:22 AM
http://shop.zzperformance.com/store/p/112-42-5-Lucas-Injectors.aspx

42.5's

http://shop.zzperformance.com/store/p/111-65-Mototron-Injectors.aspx

60's

60's are like 10 dollars more...again... why not?

i gots them sh*ts here quit sending people to competition fool

zukiracer19
12-28-2011, 11:48 AM
external wastegate is much easier to mess around with, you're not as restricted. and when it opens up, make a helluva badass sounding car.

AaronGTR
12-29-2011, 10:11 AM
external wastegate is much easier to mess around with, you're not as restricted. and when it opens up, make a helluva badass sounding car.


Again, zuki showing how clueless he really is about turbos. You don't need an external waste gate. Not with those manifolds and a 2.5" DP. Externals can give slightly better response and boost control, and they are definitely better for higher power levels where an internal one might not provide enough flow to prevent over spinning the turbine, but for lower to medium power levels an internal waste gate is plenty sufficient and should be easier to work with on your setup since it takes up less space. You don't have to have a lot of room then to fit the piping and the waste gate.

HOYS
12-29-2011, 11:55 AM
^ you act like theres nothing wrong with going way too big on injectors. too big can be a problem iirc. i'm almost stock so should i go ahead and do the 60lbs anyways b/c of my CAI?

when you get too big of an injector it sprays for such a short amount of time and sprays so furiously that fuel can puddle instead of atomizing.

Dude, you really don't know what your talking about. Stop it.

slw240sx
12-29-2011, 01:28 PM
^ you act like theres nothing wrong with going way too big on injectors. too big can be a problem iirc. i'm almost stock so should i go ahead and do the 60lbs anyways b/c of my CAI?

when you get too big of an injector it sprays for such a short amount of time and sprays so furiously that fuel can puddle instead of atomizing.


thats the whole reason for a tune... you should never change injector size with out actually changing things in the PCM. for him 60's would probably not have much of a problem idling and would be good to have so he would not have to upgrade later when he wants to crank up the boost. and anyone with a turbo car will tell you it only takes a few hours of driving to realize you are going to surpass what you had in mind as good enough HP and boost.

slw240sx
12-29-2011, 01:30 PM
external wastegate is much easier to mess around with, you're not as restricted. and when it opens up, make a helluva badass sounding car.

internal gate is easier. you bolt on turbo hook up a vacuum line and you have instant wastegate. external you have to make a dump tube figure out where to place the gate and then fab up a pipe and flange to mount it on. an it sounds like **** running open dump all the time. its like nice exhaust note then bam exhaust leak..

G.I.Ceo
12-29-2011, 02:17 PM
thats the whole reason for a tune... you should never change injector size with out actually changing things in the PCM. for him 60's would probably not have much of a problem idling and would be good to have so he would not have to upgrade later when he wants to crank up the boost. and anyone with a turbo car will tell you it only takes a few hours of driving to realize you are going to surpass what you had in mind as good enough HP and boost.
So what your saying is just go ahead and buy 60lb injectors and then tune for them? I only want to do this once and make it count. I don't cheapen anything so I will buy right the first time.

internal gate is easier. you bolt on turbo hook up a vacuum line and you have instant wastegate. external you have to make a dump tube figure out where to place the gate and then fab up a pipe and flange to mount it on. an it sounds like **** running open dump all the time. its like nice exhaust note then bam exhaust leak..
So what you pay for in a turbo with internal waste gate will save you time and a lot of headaches down the road. I was going to get get a turbo with a internal waste gate from the get go. How do you feel about Turbonetics turbos? Or do you have your own recommendations for a good turbo company? Also I do know that I want a dual ball bearing one.

zukiracer19
12-29-2011, 04:21 PM
internal gate is easier. you bolt on turbo hook up a vacuum line and you have instant wastegate. external you have to make a dump tube figure out where to place the gate and then fab up a pipe and flange to mount it on. an it sounds like **** running open dump all the time. its like nice exhaust note then bam exhaust leak..

dump it from crossover right to the downpipe... weld 2 flanges... how hard is that?

AaronGTR
01-01-2012, 10:36 AM
dump it from crossover right to the downpipe... weld 2 flanges... how hard is that?



Dude, shut up already. You are an F'in idiot.




As for injector sizing.... yes, you technically can have too large an injector, even if you tune for it. There is a limit to how short you can make in injector pulse and how far you can turn down fuel pressure before you don't have a good spray pattern and get good atomization. You might be able to get the car to idle, but it won't idle well and will run dirty at low throttle. That said, I don't think 60 lb/hr injectors would really be big enough to have that issue... but I also don't think they are necessary to support the power level he will probably hit with the other hardware he is planning to use. I think 42's would be enough. But ya know... do your own research and make your own decisions. ;) Good general rule is not to go overboard on the injectors, but pick something with at least the ability to make 20% more power than you plan on making and they should run well in the range you will run them.

grandam01
01-03-2012, 02:06 AM
Ok to help you with the problem and to keep you from listening to opinion, here is the formula. It is you goal BHP times BSFC which is typically a value of .60 for boosted applications. then you divide that by the number of injectors by the percentage of duty cycle you wish to run, (BHPX.60/6x.80) the recommended is 80% to get the most life and efficiency from the injectors, and to answer your question 42 lbs is not stock for any fbody. I believe 26 and 28 lbs were stock sizes.

How much boost do you plan on running? If you plan to make 400 bhp 50 lb injectors are the correct size to maintain the 80% duty cycle.

Here is a link to a site that has the formula. http://www.rceng.com/technical.aspx

zukiracer19
01-03-2012, 10:05 AM
I'm an idiot because my car on its best day barely runs and has never run as good as yours?

AaronGTR
01-03-2012, 05:19 PM
I'm an idiot because my car on its best day barely runs and has never run as good as yours?


Yes. And because you don't know wtf you are talking about... ever. lol

[ChaosweaveR]
01-03-2012, 06:39 PM
dump it from crossover right to the downpipe... weld 2 flanges... how hard is that?

This is why nobody takes you seriously. Ever.

zukiracer19
01-03-2012, 08:29 PM
You weld 2 flanges, one on the crossover, one on the downpipe, set the wastegate on top of it... there ya go.

AaronGTR
01-03-2012, 10:24 PM
It's not that simple. Not if you want it to work properly. But then... you don't know anything about designing turbo systems, and your car never worked properly... so I don't expect you to understand. :rolleyes:

slw240sx
01-03-2012, 10:49 PM
dump it from crossover right to the downpipe... weld 2 flanges... how hard is that?

for most people impossible, unless you can weld with bubble gum now and noone told me about it...

cost of the gate 250.00 for a real tial. cost to have that made by even a hack fabrication shop 65-130.00. then honestly some shops wont work on the stuff he bought. I almost denied the previous owner to even mess with it. imagine that a shop modifys that stuff and then the customer goes around telling people such and such shop did this. that shop now looks like it does bad quality work for people and the people with real money to spend will shy away. I know from experiance. i am a very capable and talented fabricator and doing these repair and mod jobs has burnt my rep with some higher end jobs until they see my actual high end work from other customers.


a internal gate turbo is just simpler for not much power. hell we have made 400hp on a 2L 4 cylinder with internal gated GT2871 turbos.


as for turbos, stick with garrett. i shy away from turbonectics. the failure rate we experienced while we were distributors was way too high to continue selling them. i am not talking 1 or 5 i am talking 50-70K worth in a few years. we had pretty good luck with masterpower from brazil over 40K of turbos sold and only 3 defective and those were more then likely from non primed startups.


we are a garrett retailer if you need a source to them. i can get fairly good pricing if you have a size or HP goal in mind.


as for injectors, you do run the risk of having idle problems the larger you go, how ever 60lbs is not that big and should be easy to tune for and have still idle like factory. you will need tuned and you will need to bring the car to a tuner with dyno access. so i would assume you would come down and see milzy to get that handled. a mail order tune will not suffice. your power goal dictates your injector choice, i always suggest to buy one size up from your original goal because more often then not the customer ends up wanting more then they thought and then have to sell and replace injectors which they could have just done a bigger to start and been alright.

grandam01
01-04-2012, 03:31 AM
Dude, shut up already. You are an F'in idiot.




As for injector sizing.... yes, you technically can have too large an injector, even if you tune for it. There is a limit to how short you can make in injector pulse and how far you can turn down fuel pressure before you don't have a good spray pattern and get good atomization. You might be able to get the car to idle, but it won't idle well and will run dirty at low throttle. That said, I don't think 60 lb/hr injectors would really be big enough to have that issue... but I also don't think they are necessary to support the power level he will probably hit with the other hardware he is planning to use. I think 42's would be enough. But ya know... do your own research and make your own decisions. ;) Good general rule is not to go overboard on the injectors, but pick something with at least the ability to make 20% more power than you plan on making and they should run well in the range you will run them.



I will say you are correct for the most part but 50 lb/hr would be his best bet 42 lb/hr would be for less hp and he would be close to maxing his injectors. You really do want to stay at 80% duty cycle. This puts him in the 400 bhp range. If he makes more than that then 60 lbs would be good as then he can just up the boost.

G.I.Ceo
01-04-2012, 06:54 AM
I will say you are correct for the most part but 50 lb/hr would be his best bet 42 lb/hr would be for less hp and he would be close to maxing his injectors. You really do want to stay at 80% duty cycle. This puts him in the 400 bhp range. If he makes more than that then 60 lbs would be good as then he can just up the boost.

Well 400bhp would be nice but I don't think I will be able to make that because of the internals of the motor. I have not decided yet how much of the internals I want to build up on the motor. I'm pretty sure I want to do a cam and some small stuff stuff like lifters, and springs. I am thinking too to switching to a 3500 motor and build the turbo off of that. Once I buy my turbo and I start piecing it together then I will decide exactly how far I want to take this. One thing at a time and like I said I am not in a rush because I want to make sure it's right.

zukiracer19
01-04-2012, 12:58 PM
I ran my zzp mototron 60's injectors for what 3 years with no issues... i had to mod up the rail bracket. but that was about it. All I can say is... Transmissions are a joke. Only horrible experience with my car. Also anything above 12 psi you'll need a fuel pump, other then she ran like a raped ape.

I ran a goat on 10 psi and completely crapped all over it, your car should make well over 300 with that setup.