Turbo size

MarkOfDeath

MarkOfDeath

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What size of a turbo would I need for my mark and where could I buy it
 
Brad
Pony Freak is one of the people you may want to talk to on this subject.
Fittment etc are going to be major issues with our cars. Good luck on your project, :cool: :cool:
 
no no, fitment is the easy part bro only thing Im not to sure about is oil to the turbo, Im starting this soon, my friend started on his camaro so Im following, Well I can get the exhaust reworked for fairly cheap just got to find a turbo and a dang cobra intake, I cant do much till a buy a new car thou Im thinking a toyota because I went to ford and chevy dealerships and all I could think about is how crappy they are like the cavilars and focus and the only reason to get a focus and a dell is to look for a new car when you get home, anyways got a new job so im bringing home the loot
 
I pop in and out of this forum from time to time just to check out whats going on so forgive my ignorance but is there anyone on this forum that has Turboed a MarkVIII?
 
on this site no, on any other site yes one but its not really easy on the eyes and its a drag car
 
MarkOfDeath said:
on this site no, on any other site yes one but its not really easy on the eyes and its a drag car
Click to expand...


yea, there are no streetable marks with turbos. IMO most likely, because theres no room, which is why we all do superchargers, centrifical or roots/screw/w/e
 
Brad, I would say to look into the cobra turbos, once you find out a size you may be able to go the junk yard and find some off of an import or a diesel. Turbos should be able to be fitted because all they are is an exhaust fixture. Just a matter of connecting and fitting the exhaust to it.
 
hey... found this info a while ago :) Helped me understand compressor maps for sure. Should be all the info you need to pick the correct turbo for your car

This post is to help you get past the Honda-Tech mentality of "bigger is better" when it comes to turbos, and get you thinking "properly sized is better". Who'd a thunk it?
This will make some assumptions that you under stand some basics about what a turbocharger is and a what it does.

So, lets take a look at a compressor map. This is the map for the T3 super 60.

t3-s60.jpg


You can see this is a basic 2 axis graph (x and y)... but what does it all mean?!?!?
It's really pretty simple.
Pressure ratio is just that a ratio of pressure.
Pr= (Bp+Ap)/Ap
Bp = boost pressure
Ap = air pressure (14.7psi you should know this, if not go back to school)

so if we want 10 psi PR= (10 + 14.7)/14.7
or 1.68 (we will round to 1.7 for ease)

pretty simple right?

Now the column on the bottom is Air flow lb/min, but sometimes they will be in CFM.
Oh no's what to do?
Here is how to calculate CFM

CFM = (L x RPM x VE x Pr)/5660

and to convert CFM to lb/min simply multiply CFM x .07

L = engine size in liters
RPM = what rpm your plotting the point for
VE = volumetric efficiency
2 valve engines 85%
4 valve engines 90%
ported 95%
race heads like whoa 103%
these are just estimated numbers, but should get you pretty close to what you need.
Pr is taken from the calculation we did earlier.

So if we have a d16 what kind of CFM do we need?

CFM = (1.6 x 7000 x 90 x 1.7)/5660
CFM = 302
and that in lb/min is 21

so lets plot that point.
t3-s60.1point.jpg


Not bad, at redline that turbo at 10psi is just at the end of the center island. (that’s a good
thing) but there has to be more right? Yep, we are going to have to plot 2 more points. With these next 2 points we are going to make a few assumptions. (but that’s ok, because they are almost always right.)

The 2nd point we need to plot is 50% max rpm.
Assumption 1. The turbo will make full boost by this rpm. Usually it will, or it will be really close. This is easy oddly enough the engine flows 1/2 the CFM at 1/2 the rpm (yea yea, that’s an assumption too, but again its fine)
So to plot this point we keep the Pr the same, but divide the CFM or lb/min number in half. That gives us a new lb/min of 10.5.

t3-s60.2point.jpg


this is good, the point falls on the right side of the surge line. Had it been on the other side, all hell would break loose, cats and dogs living together, real wrath of god kinda stuff.

A quick note about compressor surge… If that point (or any point) falls on the other side of the line, it is similar to letting off the throttle to shift and not having a BOV. (only a little different) The other side of that line is where the turbo isn’t pushing air out of the compressor housing. Instead the air is just spinning with it, and with the exhaust side still spinning it, it can/will create pressure build up at the turbo outlet. This is where damage to the turbo can occur, as the air can/will try reverse flow and go back though the impeller.

The last point we need to plot is the 20% air flow to make sure we don’t cross that surge line between then and 50%.
We will plot this point at 1 Pr (atmospheric pressure, no boost) and take 21 and divide that by
5 (20%) roughly 4, and then run a line from there to the 50% point.

t3-s60.3point.jpg


By looking at that map with these points, you can see that this turbo on a D16 is a pretty damn good match.

So figure those 3 points out, and go to town plotting compressor maps and find the right turbo for your application.
Click to expand...

here is a good site for creating a turbo map for a specific application
http://www.turbofast.com.au/turbomap.html

just do a google search for compressor maps once you get all the info you need and go from there :) good luck
 
Im guessing this T3/TO4E TURBOCHARGER (HYBRID TURBO)

3b_1.jpg
 
Ignoring the math for a moment, looking at it simply, if a 50 trim is a performance upgrade for a 2.4L SRT-4, which is a motor that should make around 150ish hp were it naturally aspirated, a pair of 50 trims would work well for a modded 4.6L. Also taking a look at what the aftermarket has created for the n/a Cobras confirms that something in this range would work well.

I myself have been mulling the idea of doing a low boost stock internals twin 57 trim setup (to maintain some semblance of fuel economy by being able to stay out of boost - but to make big power on the top end.) Then later on running forged internals and cranking the boost in a redonkulous fashion. Then again I might just spray it.
 
MediumD said:
Ignoring the math for a moment, looking at it simply, if a 50 trim is a performance upgrade for a 2.4L SRT-4, which is a motor that should make around 150ish hp were it naturally aspirated, a pair of 50 trims would work well for a modded 4.6L. Also taking a look at what the aftermarket has created for the n/a Cobras confirms that something in this range would work well.

I myself have been mulling the idea of doing a low boost stock internals twin 57 trim setup (to maintain some semblance of fuel economy by being able to stay out of boost - but to make big power on the top end.) Then later on running forged internals and cranking the boost in a redonkulous fashion. Then again I might just spray it.
Click to expand...


you are correct... that should work fine IMO, but if you want to engineer yourself the most efficent setup possible, the math data above will help find that "sweet spot" so to speak

good luck guys... I'd love to do a turbo mark VIII setup someday
 
MarkOfDeath said:
no no, fitment is the easy part bro only thing Im not to sure about is oil to the turbo,
Click to expand...


If I may ask, where exactly can you find the room to mount two (or even one) turbos upfront? The only feasible monting sport on the marks is way back, over the ehhaust mufflers.

Am I missing some large hidden spot upfront in the engine bay?
 
Provided you know some of the specifics of your setup, here's a calculator I made that may help. It does the 'math' for you.

http://www.sovapid.com/PaulTurboCalc.htm

*edit* - let me give you an example:

So, my motor is 422 cubic inches, max RPM for me is 6000. (that's a lot of stuff swinging around in there)
I estimate Volumetric Efficiency around 85-90%, but I'll use 85% in order to be conservative. It may be higher.
Desired boost pressure is 6 psi since I want to stop around 550-600 hp.
Inlet Temp here in Phoenix will be around 100 degrees Fahrenheit.
Adiabatic Efficiency of the compressor I was using for this (a Vortech T-Trim) was 72% for 1.41 bar and ~50 lbs per minute of air. Although I could also use 70% AE since it is right on the border.

The end result is that I find it is difficult for me to find a compressor that is efficient with such high CFM at such low boost pressure. This is because my motor is friggin' huge. I'd likely need a pretty big compressor (read: T-trim or larger, or T88 or larger) to be efficient at such low pressure ratio.

This will help give you an idea of where you want to be with different compressors. For more information, I'd go to www.turbomustangs.com and read the 'knowledge base' to learn more about turbos, turbo selection, compressor maps, and so on.

Paul.


PS - all 281 ci modular owners should note the humor of we 'pushrod' guys.
 
That's a neat calculator Dr. Paul. I used it to dream about turbos for my 573, just don't know where to find anything that'll flow 126lb/min.
 
i guess the 281 is the only homo modular motor? what about the 5.4 or the 6.8 :)
 
let him have his rod throwing block splitting 5.slow
 
If finding space in the engine compartment is an issue, have your considered a remote turbo (rear of the car)? WWW.STSTURBO.COM has turbo kits for almost any application. I've seen them mounted on mustangs and camaros. Just an idea/option.
 
Mark Of Death, Just Buy A Supercharger. Intake Comes Off, Supercharger In, Alternator Relocated And Poof An Extra 150hp. Why Snake The Exhaust Like Intestons And Have Turbo Lag, Superhot Engine Compartment, Etc.

Supercharging The Best Way To Go And You Can 1 Up Your Camaro Buddy By Getting A Custom Licence Plate For Him To Read All The Time Trying To Keep Up, Or Get Yourself A Rearview Camera With Tivo So You Can Watch Your Buddy's Turbo Explode..

Peace And Good Luck
 
95devillens Come On. Like Most Who Are Dumb Enough To Buy A Front Wheel Drive Golf Cart From Cadillac, You Post A Picture Holding A Gun, Wow. My 98 Year Old Decrepid Granny Can Hold A Gun And Blow You Away, So Whats The Point. Real Men Use The 8 Nuckles God Gave Them And A Size 12 For The Final Blow As There Means Of Domination. Just Like The Caddy And The Gun, You Chose The Stupid And Pansy Way Out. I Could Race My Mark In Reverse And Beat Any Caddy, They Are Junk.. Front Wheel Drive? The Only Fishtailing You Will Do Is On Your 8 Foot Bass Boat When You Catch A 6inch Bluegill For Dinner Bro....

Stay In The Loser Forum, Cadillac........
 
95LSC 2FAST4U said:
Stay In The Loser Forum, Cadillac........
Click to expand...

You need to chill out a bit man. 22 posts and you're making posts like this. Come on. This is not how we do it around here.
 
The problem with the STS turbo setup on a Mark VIII isn't the mounting of the turbos, the problem would be running the air back up to the motor as the output side of the turbo would be almost like running another complete exhaust system back forward. Plus I'm not thrilled with the air cleaner being right above the road. But that's just my opinion.
 
I'd like to see some one do this. I think you could take either 3" or 4" and ovalize it to run the boost side forward. Definetly another approach that may be worth pursuing. A car with that much power wouldn't be a daily driver anyhow, as you would need dry pavent to drive it on, and I think re-located airfilters could accomplish thier task. :cool:

Engine 1.jpg
 
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