Project Turbo LS1 by ColtGT4g63

By stevegolf
( 3 )

Project Turbo LS1

Compliments of ColtGT4g63 @

Hey guys, So I recently decided to go with a turbo instead of going with the Heads / Cam / Intake / TB package, or NOS route. I'm going to be building my own manifolds, and piping, and everything else. I've pretty much got everything I need, just need to get crackin on it when time lets me. I'll be updating with pics of everything along the way, thought I would share. My goal is to gain at least another 100hp, and spend as little money as possible. Here's what I've got so far. 

For manifolds I've decided to build some Log manifolds. Due to basic design, cost of materials, and simplicity I was able to finish both manifolds for roughly 200$ They should do the trick. Took a couple hours to build both.

I've already picked up a wastegate, ( same wastegate that dustin280zx is using in the Gen 1 / 2 V8 threads. ) And for Blow off valves I'm going to be using 2 factory blow off valves from an early 90's Mitsubishi Eclipse.

I ordered all my Oil line fittings from Summit and picked up a few from Home Depot, Never knew how cheap buying AN fittings could be. I was able to find a few of these fittings for less then 5$ pretty sweet. I also got an Ebay intercooler. Which should fit, and perform well.

And for the best part of it all, the turbo... I ordered a GT45 Ebay turbo. Knock it all you want, but the price was soo cheap that I figured it was worth a shot! After all, its got a divided T4 flange so if it ends up breaking, I have plenty of options for a replacement. price was 330$ shipped. The shaft spins perfectly fine, and continues to spin when you let go. Zero in / out shaft play. Normal, minimal side / side play. I can't wait to run this thing! 

So thats all I've got for now as far as pics go. My Z is up on jack stands, all the N/A stuff removed just waiting for this weekend. Like I said, I'll be updating with pics and info along the way. Enjoy!

For the manifold: I Just decided to build my own so I know it's going to fit how I want it to. It also makes me feel pretty good about myself when someone asks. Where did you buy the manifolds from? and I can say.. "Ya, I built those myself." 

For the heads: I've got some 243's off of an 02 ZO6. Suppose to bump compression to 10.4:1. With that said, I'm going to be running pretty low boost

For engine management, injectors, etc.: I'm getting some 60# injectors and am going to be running some duel Walbro 255's. For the time being, I'm gonna run the stock Vette regulator / filter. Eventually I'm going to swap to custom fuel rails with a boost (whatever you call it) regulator. For management I'm using HP tuners, Starting off with blow through MAF, and will eventually swap to 2 bar Speed Density.


So I got a bit more work done to the car this weekend. I got my brace all finished. Its pretty beefy, but very ugly. As long as it works, right? Got the intercooler all mounted up. Also got the manifolds bolted into the motor. I finished up my collector, and got it connected to the driver side manifold. I'll post pics later. I am POOPED! Time for some Taco Bell. 


Most of my buddies said the same stuff. "That turbo is going to fall apart!" ect ect ect... I've heard it all. "Those compressor blades are glued on." Hah. Anyways... So heres some pics of what all I did. For starters, Heres a bunch of intercooler pics. Had to of been the easiest, fastest, and smoothest intercooler install I have ever done in my life.

Heres the "modified" manifolds installed. Compared to the original ones I had, there is a bit more room between runners to get some spark plug wires on there.

I spent the rest of the weekend working on the support bracket(hideous, I know) , collector, and middle section of the manifold.

Oh yaaa, I forgot to mention. All the welding, and fab work is done by yours truly. And the welder I am currently using is a 200$ Harbor Freight, scratch-to-start tig. Works bitchin! 

The cross over pipes are 2.5" 304 stainless. Tonight after work I pulled the pan and will be getting the oil return bung welded on tomorrow. Hopefully getting the pan installed back on the car tomorrow as well. 


Well, last night I got my pan pulled off. Brought it into work today and drilled me a nice big hole. Brought it over to a friends house who could weld me a bung on it after work, came home and installed the damn thing! pics!

And for the pics you've all been waiting for! Its not bolted down or anything, nor is the manifold done, but this is where the turbo will be sitting for the most part.



Unfortunately I don't think I'm going to get my V band pieces in time before this week end either so I may not be able to start the down pipe until next weekend. Hummm.... Tonight I got my upper intercooler pipe all finished up. Got both Blow off Valve flanges welded onto it. As well as finished welding the fittings for the oil lines. My goal is to just start the car up this weekend with open turbine housing. Should be fun! I wanna make the Neighbors think that a jet is taking off on our street.  


So Heres a few pics I snapped of some of the progress I've made during the week. I'm getting pretty anxious for the week end to arrive!!! 

Harbor Freight tig welder at its best!

The Vband parts are all mild steel, I picked it all up from, Which is also the same place that I picked up the stainless bends to make the cross over pipes on the manifold. They've got quite a bit of DIY stuff, as well as others things too, and they're pricing is pretty decent. I picked up the BOV flanges from a shop I use to work at called RoadRaceEngineering, they've got a whole bunch of DIY parts as well. 

You can get those blow off Valves off of any 90 - 94 mitsu eclipse, Eagle Talon, or plymouth laser turbo. I already had one in the garage from my old car, and picked up another for 30$. Much cheaper then going for a single bigger one.


This rain is freakin killin me! But I squeezed in a little fabrication time last night while I could. I pretty much finished the manifold entirely, with the exception of the external wastegate. And I didn't get my final Vband pieces so I won't be able to make the down pipe this weekend either. Once the rain lets up I can finish up the both intercooler pipes. Wire in my pusher fan. And try to wrap up any other misc. pieces that need attention before I fire it up!

Heres a few pics of the cross over section of the manifold all finished up. 


So after work today, I decided that working on cars for 9 hours wasn't enough. So I pulled out the 'ol chop saw and fired up the welder. I got all my intercooler pipes painted, and finished up my down pipe. All I've pretty much got left to do is get the external wastegate welded on the manifold, and reinstall everything. Run a few vacuum lines then its time to fire this baby up!!! This weekend for sure... Heres some pics of the goods.

Sorry! No pics of the down pipe installed on the car.  I'll save those pics for later so the dying minds can sweat it out a little more. Haha 


Okay I'll stop with the torture already, and post up my down pipe pics. 
The turbine outlet is a 3.5" outlet, but since I want to run the exhaust OVER the cross member, I had to step it down to a 3" 

There is a small pocket right under the passenger side mount that is about 3.5" in diameter. This is where I ran my exhaust though. It was TIGHT TIGHT TIGHT fitting it, and its close to stuff, but everything will be wrapped, so I don't think it'll cause any problems.

right after the engine is where I'm going to step up the exhaust diameter to 3.5". For now, I'm just going to run open down pipe  


This just in.... The car runs!!! I finished up everything else I needed to to today in order to fire it up. Started first try and I ran it for aprox. 20 seconds. I'll giving it some of the finishing touches over the weekend that will make it somewhat drivable. Heres some of my final pics.

Oh ya! I forgot... heres a video of the first start up.


with some creative working you can fit a CAI in there


So heres an update with the car... I finally got it drivable and took it out for a spin. Car miss fires like crazy! and will sputter pretty much the entire time while driving. Hard to say what it is but I think its ignition related. Possibly my plug wires. Whats funny is, if I give it a little more throttle it'll get through the missing and run smooth for a sec. I'm going to try a new set of plug wires, and also see if I can borrow a maf to try. Kind of disappointing, But I at least accomplished my goal for the weekend and got the car running.  


Okay, so I think I have narrowed down the stuttering problem to one of my O2 sensors. I hooked up the HP tuners to the car and sat down with it to do a little diag. I found that bank 1 O2 is stuck at .1v and causing the fuel trim to max the F out. Injection timing for bank 1 was 4 times the p/w of bank 2. So whenever the car was in closed loop, it would jump WAY too much fuel and the car would bog. This explains why the car would run better when cold, and would eventually run smoother if I gave it more gas. I have ordered up some new O2 sensors and hopefully will get them by the end of the week so I can throw 'em in. I also got my 2nd fuel pump, and 60# / hr. injectors so those will be going in the car this weekend as well. Along with a larger fuel line. I also ordered a 2 bar Map sensor for when I convert the car over to speed density. I also got me a screw in IAT, so I have to weld a bung unto the IC pipe as well. Luckily I have a 4 day weekend this weekend so ALOT of stuff will get done. If my O2 sensor come in, I'll try to make a driving video with some cool noises for everyone.  


I think I would like to keep it in the 500hp range. That should be fast enough to scare the ♥♥♥♥ out of me, who knows... I've got plenty of outside car pics.


Well I ended up having to redo the exhaust, it was hanging WAY too low. Tuesday my O2 sensors should arrive, then I'll be able to take the car out and do a little tuning. Trust me, video's will happen as soon as the car is video worthy.  


This just in... I got my new O2 sensors installed and was actually able to drive the car!!! WAHOOO!!! BTW, the turbo sounds amazing. Now for my next set of issues... Smoke out the tail pipe under any boost. I can have the boost gauge at "zero" at any rpm, but the second I see 1psi + I get smoke. I need to get myself a catch can, boost in the crank case is bad.  I also need to adjust the oil return line a little so its at a constant downward angle, and install my oil feed line restrictor once it comes in. So this coming week end i'll work on that stuff, as well as get the injectors installed and hopefully converted to speed density. Actually driving the car and hearing the turbo spool was worth the entire wait. 


Okay, I re-routed the PCV lines, added an oil feed restricter and took the car out for a spin, NO SMOKE!! WHAHOO! So I installed my 60# injectors, and went out for a little cruise. Ya, the video sucks but you can get an idea of how loud the turbo is, and how fast it spools. So far, this China turbo is doing an alright job.  


I swapped the car over to the new heads just this past weekend and got it running. Have fatty exhaust leaks on the header flanges from re using the factory gaskets too many times.  Also... Before I take her to the track, I need to finish the roll cage, install the drive shaft loop, and buy me some fire proof clothing. And get the boost set with a good amount of tuning. I already know the car is going to be a monster. I went out for a little test drive, hit 6psi at roughly 1/2 throttle and left a certain individual's RB26 powered Z in the rear view.  I am going to run about 10 psi and tune with that. 

I've got a 14" spal pusher stuffed between the radiator and the intercooler. Seems to be doing the trick. This car is going to be down for a little while. I can't seem to get it running right, and its doing a very good job of frustrating the hell out of me. I need to take a step back and relax. Seems like it only runs good at WOT, which would be good if it was a track only car. But my intentions for the car are to have a reliable, drive every day if I want to street / strip car. ugh....

I'm not running the 2 bar speed density yet, I have to get a whole other PCM to do so since the serial number burned into my current PCM is not identifiable. Anywho... the car starts running like ass when I'm just cruising. Not even in any kind of boost. I'm honestly contemplating selling this kit. Who would be interested? And what kind of price range would it be worth? I have no idea. Things were much less complicated when I was N/A. Ahhhh the good 'ol days..


Well, its official. 

Ya, I really like the whole build process part of things. And now that I'm done with the turbo build, I'm craving something else. How about 1,000$ plus shipping? 


Well.... I pulled all the turbo stuff off the car this last weekend. I blew out another exhaust manifold gasket. I bought some bling carbon steel exhaust gaskets just for this reason, and they took a dump in less then 100 miles. This is the second set of gaskets that I've put on the car in less then 200 miles. If I'm already have problems like this after only a couple hundred miles... I don't want to even imagine the kind of issues I'm going to run into after a couple thousand. Anyways.... I'm converting back to N/A, I hung onto my heads for just such an occasion. I'm going to try and make as much power I can like this, and see if I can accomplish my goals at the track. Everything is for sale BTW! If you want any particular pieces, let me know. 


So after much search for a way to get rid of my old turbo log manifolds I have finally found a solution. Being a lurker on "theturboforums" I found a guy using C6 vette manifolds flipped and upside down. They point forward / upward. And since they hug the block pretty good, I ordered me up a set and threw them on the car for a test fit.

The passenger side comes pretty close to the inner fender, but it does not hit. And the closest point is just the outer portion of the flange anyways, no biggie. Naturally, I had to change the mid section on my manifold in order to accommodate the new manifolds. Nothing that the 'ol harbor freight tig can't take care of!

I have also changed a couple other things with the car. I'm now running 317 heads Vs. my old 5.3 heads. Goal was to lower the compression so I can run some more boost safely. And I'm using an LS1 intake manifold Vs. m6 old LS6 manifold. (Had to borrow the LS6 for an N/A project) So the difference by ONLY swapping the manifolds was... no tire spin on the freeway, to: now I've got some tire spin on the freeway. I'm only running about 8 - 9psi too. Tomorrow I am taking the car out to the local 1/8th mile strip and as always... Will keep you all posted. Probably have a movie to post as well. Till next time. 


I have also considered a twin set up. But think that you would just have twice the piping running everywhere. Who knows... I picked up a set of C6 manifolds off ebay for 83$ shipped. Not too bad in my opinion. Seems like with the new manifolds the turbo spools up a little bit quicker. Which is a relief! It was pretty laggy before. So Tonight I took the car out to the track. As always, ran into some snags... But Also ran some of the best times I ever have. The best time slip is: 6.6 @ 104 with a 1.52 60ft. Next best slip is 7.8 @ 106 with a not so good 60ft. On the 106 run the car was bogging / sputtering on the Tbrake some, and also off the line. Once I hit the 60ft. mark the car took off like nothing I have ever felt before and still trapped 106. Seems as if my old manifolds were holding me back big time! Every small turn of the boost controller would give me VERY noticeable gains. With the old manifolds, every time I upped the boost the car would get slower. And tonight I was able to run as much as 12psi.


Sweet ride!

Posted by Diggymart on 10/24/18 @ 2:23:27 PM