Iron 6.0L
4.030 bore
forged rod/piston, stock crank
317 heads
proflo xt intake
90mm tb

Ive got everything pretty well figured cept for the turbo's and injectors. talking with the engine shop that did the machine work for me about some precision 76's but still need to decide. im looking for around 800rwhp, roughly 15lbs of boost on pump gas. more boost will come, but i just built the motor and dont plan on trying to kill it anytime soon. vehicle is a 69 c10 that will be a street legal build, set up for drag dracing. being my first fi build i am quite noob and any and all advice is greatly appreciated.

thank you,
kyle.

 

Are you dead set on twins?

 

I have been talking to a guy on here that knows alot about the turbos. My advice is build the motor for boosted if that is what you want to do. Get it in there and have it dyno'ed NA. Now with that info you can figure out how big of turbo you need by the hp you want to run. Say you you have 400 hp NA so by boosting it by 14,7 you roughly double the power so you have 800 and you want a 1000 so you roughly another 3-4 psi( ( 14.7/2)= 7.3 gets you down to 400 divide again by half est 4 spi) so you need 18.7 est 19 psi to make the 1000hp out of a 400 hp NA motor. Now go look at the turbos that will do that psi as a pair and the hp level. for example single turbo that makes 300 hp so with the pair you get 600 hp now add that to the 400. Now you need to look at the maps and where you want to make the power? Street/Strip or just Strip. S/S will be a little smaller turbo and the all out peaky power for Strip will be a bigger one.

That is how I am going to go about it...should know hp levels today or tormorrow. And gonna go from there.

Take from this as you want, but I would take this info and go talk to a tuner and see what he has to say about it......and willing that he will agree if he is a good one.

Sorry for being so lengthy. He might join in here also......I have to give him Props he knows his stuff..........

 

thanks for the replys. yes i am set on twins, just been a long term goal for me and theres no time like the present. Bigtoyz i agree and that is actually my plan. i built the motor for boost with forged diamond pistons and scat rods, gapped the rings and already got my mani's flipped lol. i just need to finish my wire harness (hacked stocker) and get injectors then its ready to dyno.

i should have worded the original post better, but what im looking for is a suggestion on injectors. by the injector calculator in the fuel section i need to go with at least an 80lbs injector but figure ill go higher to keep on the safe side for when i up the boost/fuel consumption. ive seen guys with similar setups going as far as 160#'s but figure id toss it out to the guru's and get suggestions on both flow and supplier. the speed shop that did my motor has a guy that specs injectors for individual builds and has excellent reviews but comes with about a $900 tag.... which i dont mind pony'n up for but I want to see what other options exist.

and pictures always help, heres my airpump. the ls6 intake is my buddy's just sittin ontop.

 

I think you got the right idea.......really doesnt matter with the low imp injector anymore. So if you go bigger its not gonna hurt you. Now if you go E85 now there you will have to get some biggins

 

haha yeah, no e85 for me. theres only a handful of stations servicing e85 in canada and im not even in a province that has one. so im going to stick to the traditional route, debating on setting up a secondary fuel system for racing fuel but thatll be as far as it goes.

whos got a good injector manufacturer/supplier i could contact?

 

Incorrect- the turbo(s) have to support the total HP- Not 600.
You also have to size the turbines to match the motor and compressor which is harder.

For 1k twins, you'd want 5862's minimum. 6162's or 6262's for better street performance (spool), 61 or 6265's for strip, or 6465's or 6765's for lots of room to grow. All on a T4 and preferably a 4" compressor inlet. The 6165's are probably the cheapest of the group money wise. I'd do a 61 mm compressor for what you want.
6162's will support about 1300 fwhp. Some run the smaller 60-1's. But I like the map on the 61 mm the best.

Since your up north, I'd go with Racetronix. There's a link on the right.

80's are all you need since you don't plan on going E85.

 

sorry I goofed up on what I said above....the turbos have to support the total power you want, but the rest of it was correct. I'm still picking up on this stuff also.

TurboS10 have you looked at the T58's from turonetics? Think they make a great street turbo......and will make pretty good power also. Is about the only one that I have found that has that kind of map. A friend of mine turned me on to these for twins.

 

And if running them on the street in the 600-700 hp on the street they are 77 percent effient area.

 

awesome thanks guys. ive got some things to look into!

 

I was at work and did a big replay to this, and this site logs me off at work constantly and my reply got lost in the re-log in and refresh shuffle. I am too tired to redo it after working all night. But how much HP your engine can / should make naturally aspirated is the big heavy hitter in the calcs. This when figured with how good of a set youre going to run will give you a good idea on what boost range you should be in to hit your desired hp level...example: Turbo needs to flow 500hp worth of air at 15 to 19 psi. Once you have numbers like that you can look at compressor maps and see how well a turbo will be working at those numbers.

 

sweet thanks for the reply, its too bad your original didnt make it! ive got no idea what my motor will make n/a but thats why im trying to get some injectors so i can take it for a dyno tune, and once ive got the n/a dyno session done i can better select the turbos. by the calculations ive done from different sites im arriving at 80# injectors. im trying to read up and better understand how injectors are tested/rated right now cause i feel in over my head trying to decide on one. espessially with the prices im seeing i definitly want to make sure i make the right decision, ONCE.

 

Injectors sizing used to be stupid easy but the higher base fuel pressure the LS motors run at change some of the calcs. Also are you going to run gas or E85? are you going to run the standard LS base fuel pressure? And once again how much hp are you going to make. More info here would be needed to do the calculation.

Btw: If you made around 800 rwhp on on a 6.0L around 15 psi or more boost then a pair of good 63's would be working at a good efficiency. Remember to cut everything in half, or to double it. example 800 rwhp would be 400 rwhp per turbo

You have a 6.0L motor that means you have 3.0L of spool up power going into each turbo. You also have to look at how good your motor breaths. In your case you will have an good breathing 6.0L, so you have good breathing 3.0L spool power for each turbo. An awesome breathing 3.0L may spool a 76mm half way decent at the track, but a good breathing 3.0L wouldnt spool a 76 very good at all on the street. When properly set up a pair of 61's to 63's would make that thing feel like an absolute monster on the street, and probably shock you at the track. Except you would have driven it on the street first so you wouldnt truly be shocked, you would have already known it was a monster. Your cam and head combo will dictate how much rpm you will make good power at. If Cam / head / rpm combo is mellow like low 6k shift points you would be surprised at the power you can get out of a pair of 58's. A pair of 58's can make 1000 flywheel hp and be efficient doing it. They just wouldnt want to make 1000 hp at some low boost number. Thats what the compressor map is showing that bigtoyz posted.

A properly matched set up RUNS HARD EVERYWHERE. On similar set up motors I have seen single 58 kick the crap out of a single 72, and a higher flowing motor with a 63 absolutely destroy a 72.

Look real close at that 58, 63, 72 example above. This was at the track, not on the street. That 58 is supposed to get spanked at the track by the 72. The 58 got out of the hole real good and since it was sized more appropriately for the motor it still laid down a good mph out the back door. The 72 was a turd out of the hole and when it did get going it didnt lay down some big mph. I think it went out the back door around 1 to 2 mph higher than the 58, remember this was at the track where the 72 was supposed to shine. On the street, if you thought they guy with the 58 was laughing at the 72 at the track.....yeah it was bad. The 58 was a better matched set up, it ran hard everywhere, for what it was. The hit in performance the 58 should have taken at the track was greatly minimized because it was a matched set up.
Now look at the 63 set up. This was a better flowing motor. It had better heads, and better cam, it would make more hp NA than the other two motors. Alot of people would argue that this better breathing motor should get a big turbo, like a 72 and hold on! The owner was wise enough to resist the big turbo and picked one that was properly sized for how well his motor was breathing. It also flowed enough air to to still spool a 63 pretty damn good. So better flowing motor with a larger but still properly matched turbo, it ran even harder. It ran HARD EVERYWHERE, for what it was.

Dont take from these last examples that you need to buy these or stay away from those. Its about the importance of having a matched combo. That said, you would have to have a pretty wild combo for 76's to start looking like a good choice. Something much closer to 60mm would be a hard running choice.