Low compression 383 turbo selection
Thread Starter
Staging Lane
iTrader: (3)
Joined: Aug 2010
Posts: 84
Likes: 1
From: South Central Missouri
Low compression 383 turbo selection Ok here's what I'm starting out with. Car is a 97 Trans am convertible with ls swap 383. It's 9:1 compression, eagle rotating assembly, 243 heads, ls6 intake, head studs, 228/234 115 cam, twin 255s in tank, #60 injectors, and a4. The current setup is a rear mount cx racing t76 ceramic ball bearing with .96 exhaust housing and I plan on doing a front mount this winter.
My plans are to be in the 800-1000hp mark. The car is a cruiser with the occasional track day so don't want too much lag like I'm having now. I'm really starting to head towards the twin cx racing ceramic ball bearing gt35's with t4 .68 housings. I've heard lag and no lag from different threads so I don't know what is right. I'm thinking because of my low compression it could be more laggy. My question is should I put my current turbo up front, twin gt35's, or something else bigger or smaller?
My plans are to be in the 800-1000hp mark. The car is a cruiser with the occasional track day so don't want too much lag like I'm having now. I'm really starting to head towards the twin cx racing ceramic ball bearing gt35's with t4 .68 housings. I've heard lag and no lag from different threads so I don't know what is right. I'm thinking because of my low compression it could be more laggy. My question is should I put my current turbo up front, twin gt35's, or something else bigger or smaller?
TECH Enthusiast
Joined: Jul 2013
Posts: 617
Likes: 0
From: Okmulgee, OK
First off. Bigger injectors.
Second, I would really go with a better brand of Turbo, Precision has "Entry-Level" Turbochargers that are just as cheap, and more reliable than those CX Racing Units.
Second, I would really go with a better brand of Turbo, Precision has "Entry-Level" Turbochargers that are just as cheap, and more reliable than those CX Racing Units.
Thread Starter
Staging Lane
iTrader: (3)
Joined: Aug 2010
Posts: 84
Likes: 1
From: South Central Missouri
Ya I forgot to mention 80# injectors would be on the way. I haven't seen a precision ball bearing turbo for $400 shipped unless I just haven't looked. The cx racing turbo I have now is pretty nice quality and the company has great customer service. If I could get a precision that cheap I would be all over it.
Thread Starter
Staging Lane
iTrader: (3)
Joined: Aug 2010
Posts: 84
Likes: 1
From: South Central Missouri
Well if they can match the eBay turbo price I will go with them but I'm still in the question of size that I need for my setup. I am in a tight budget as everyone usually is so the cheaper the better without going too cheap. I've found out I'll never go as cheap as on3 again but cx racing does have a fairly quality product for the money from what I've had experience with and they do back their product.
TECH Enthusiast
Joined: Mar 2012
Posts: 728
Likes: 3
For now, front mount the same turbo. You'll spool a lot sooner with more power potential. From there you can upgrade to the CX 80mm if you want over 800 or ab S475 or even 480 for 700 bucks and get the power you want without having to redo everything.
Thread Starter
Staging Lane
iTrader: (3)
Joined: Aug 2010
Posts: 84
Likes: 1
From: South Central Missouri
The thing is I don't want to change my setup again if I'm not satisfied. Has anyone used a set of gt35's? Right now they have a sale on ball bearing t4 housing gt35s for $404 free shipping or $279 free shipping for journal bearings with ported housings. I'd like to not be maxing turbos out to squeeze hp so I'm thinking two will take less effort to make more power than one. I do car shows too and I like the look of twins but my main concern is finding the right size since I'm using a lower compression ratio.
Trending Topics
TECH Enthusiast
Joined: Mar 2012
Posts: 728
Likes: 3
Compression doesn't effect spool as much as you would think. While it does have an effect, most people would have trouble really noticing it. A one point bump might net you a couple hundred rpm sooner on similar tunes. Most people wouldn't notice 150-200 rpm in spool.
Your cam and torque converter will have a much greater effect on spool.
Your cam and torque converter will have a much greater effect on spool.
Last edited by HexenLord; Oct 31, 2013 at 12:55 PM.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
9:1 is low compression these days huh? What size is the exhaust piping leading to your turbo now? Is that a 65mm exh. wheel on your current turbo?
Your power goals seem a bit lofty. 800-1000hp for a cruiser? With 29x12" slicks and 3.10 gearing anything over 17lbs on my setup (well under 800hp) is totally useless on the street. Even rolling into the gas at 50mph I'd blow the slicks off. I'd guess thats around 600whp and I'm geared much taller than most.
With traction control and a few other tricks people do manage huge power on the street , but its a constant struggle and most of the power isn't applied to the wheels until the cars already going well over 100mph.
I'd bet it would make a night and day difference with a much smaller cam, properly sized hotside, and larger turbo on your curent setup.
Your power goals seem a bit lofty. 800-1000hp for a cruiser? With 29x12" slicks and 3.10 gearing anything over 17lbs on my setup (well under 800hp) is totally useless on the street. Even rolling into the gas at 50mph I'd blow the slicks off. I'd guess thats around 600whp and I'm geared much taller than most.
With traction control and a few other tricks people do manage huge power on the street , but its a constant struggle and most of the power isn't applied to the wheels until the cars already going well over 100mph.
I'd bet it would make a night and day difference with a much smaller cam, properly sized hotside, and larger turbo on your curent setup.
Thread Starter
Staging Lane
iTrader: (3)
Joined: Aug 2010
Posts: 84
Likes: 1
From: South Central Missouri
9:1 is low compression these days huh? What size is the exhaust piping leading to your turbo now? Is that a 65mm exh. wheel on your current turbo? Your power goals seem a bit lofty. 800-1000hp for a cruiser? With 29x12" slicks and 3.10 gearing anything over 17lbs on my setup (well under 800hp) is totally useless on the street. Even rolling into the gas at 50mph I'd blow the slicks off. I'd guess thats around 600whp and I'm geared much taller than most. With traction control and a few other tricks people do manage huge power on the street , but its a constant struggle and most of the power isn't applied to the wheels until the cars already going well over 100mph. I'd bet it would make a night and day difference with a much smaller cam, properly sized hotside, and larger turbo on your curent setup.
Compressor Inlet 4"
Compressor Outlet 2.5"
Bearing Ceramic Ball Bearing on Compressor Side Compressor
Cooling Oil +Water
Oil Cooling Fitting 1/8" NPT Feeding. M8 x1.25 Return Flange Mounting Screws
Water Cooling Fitting M16 Threaded
Flange Standard T4
HP Rating 500-700 HP
Internal Wastegate None
Compressor 76mm Wheel Compressor
Turbine P Trim .96 A/R Turbine
Compressor Wheel 102.4mm/76.7mm
Turbine Wheel 74.1mm/64.6mm
Hot Side 3" V-band
Last edited by fireburr; Nov 1, 2013 at 07:32 PM. Reason: missed some info
