picking a turbo

71 GrandPrix SJ · 10-08-07, 01:17PM

Hi I am new to this board but have been a PY member for some time and referred here by a member over there to turbo discussions.
I am starting a BIY turbo setup over the winter and want to start by selecting a suitable turbo. fisrt off im keeping this very streetable and am only looking for 7-8psi to start with. My goals are modest at about 550 hp. currently im running a 71 grand prix wieghing 4280 without me in it. current motor is a zero deck 461, 6x heads 246/209cfm 2.11/1.77 98cc with 9.3:1. rpm intake 850HP, crower rods, SRP pistons stock N crank. cam is what i am worried about. its currently a nitrous grind at 241/253@50 560/560 with 1.65 112CL. this cam ok? 700R4 trans 10''2800 non-lockup converter 12bolt 3.42 gears. well as is the car has been a best of 12.43 on motor with no good nitrous passes yet.
i want to start by picking the turbo and it has been recommended that i use the s400 with a 5" downpipe. would this suit my needs? after i choose this i will go to the next steps with questions following. Im very nesw to turbos. have been a nitrous guy for some while.Thanks _scott

71 GrandPrix SJ · 10-09-07, 01:05PM

guess this forum is not as popular as i thought?? over a day and only 13 views?

fast72Lemans · 10-09-07, 08:07PM

Wish I could help, I played for a couple of years with the supercharger, and gave up. Back to juice for me.

Mark

Lil Jack · 10-09-07, 08:39PM

Nitrous FTW!

fast72Lemans · 10-09-07, 08:54PM

Awww sheet.......look what I started!

turbo69BIRD · 10-09-07, 09:00PM

I would like to suggest the TV7101 or qTV71/81 hybrid
I like these turbos because they are what Turbonetics based many of thier turbos off.
I have put a bunch of these on pontiacs over the past few years and have sold many of them too.
You can get them for under $1000.00 shipped and they are sized perfectly for your combo.
I would also suggest a .96 housing on the hot side. There are many other turbos that will work but these are in my opinion the best bang for the buck.

Your cam will probably work but an optimized turbo cam will add a lot of HP and torque the big issue is the overlap. A 114 LSA is usualy a good place to start.

550 Hp is easy to make with about 6 psi with that combo.
If you look at wallace racings web site they have a great calculator for boost to compression.

you can also use a BTM for knocking back the timing under boost for better octane tolerance.

you can also set up your own carb for blow through or you can get one from CSU or a guy under the name hangar18 over at turbomustangs.com

A really good fuel system is also a must because at a higher pressure the pump will have a lot less GPM. when you add boost you must add equal pressure to the fuel system to balance it out

I hope this is helpful and coherent I was playing with my 2 year old while writing it.

71 GrandPrix SJ · 10-09-07, 10:17PM

fast72lemans- not sure if you remember me but i came up to your house with a couple buddies. one of my friends wanted to by your grandprix you had for sale a couple years ago. he ended up buying an 87 T-Type. anyway i remember your supercharger problems
turbo69bird-- the s400 has a 1.34 on the hot side what exactly does that mean? and how fast would it spool i imagine i would want it spooling fairly quickly if im shifting at 55-5700 rpms. i know all about the carb stuff and fuel systems because i spent 3 months researching a blowthru centrifugal system i was hell bent on using but after driving my buddies GN and another guys typhoon i am officially hooked to turbos. my car was faster than those cars but i love the power band. cam is no biggy and could always change down the line. i keep looking in amazement how nice of a turbo cam the 041 would be! but like i said im just learning the basics and will post different questions once i get a hold of the early stuff.
also i personally do not like the mustang forums yes they are full of great info but most of those "know it alls" are j*offs i dont see the point of participating in a forum for giving and getting information if your going to knock all the little guys who dont know much.

Gach · 10-09-07, 11:25PM

FTW! could some one explain what that means

Mo Money · 10-09-07, 11:29PM

Quote:

Originally Posted by Gach

FTW! could some one explain what that means

"For the win" or "F the world" your pick.

"Nitrous, for the win!" game show talk, according to google. HTH.

Mo Money · 10-09-07, 11:41PM

For the money, I like the S400. It dose have a 1.32 a/r but I haven't found anyone say it's too big for a 462. It can be modified to spool a little faster with a 100 shot

.

turbo69BIRD · 10-10-07, 12:22AM

Quote:

Originally Posted by Mo Money

For the money, I like the S400. It dose have a 1.32 a/r but I haven't found anyone say it's too big for a 462. It can be modified to spool a little faster with a 100 shot

.

I am not familiar with the S400 but I can say that on the TV series turbo I wouldn't run a 1.32 housing unless it was a much higher RPM engine with better heads than I run.

If you look at what the chevy guys are running it is misleading because most of them run a higher RPM range with a killer set of aluminum heads.

I know I ran a 1.30 on my car and it was horrible. I then dropped down to a 1.23 and it was OK but when I started to run the .96 the car was like an animal.
I wouldn't want to run a 100 shot to spool it that seems like band aid to me why not run the right housing and run the 100 shot anyway. Or maybe go DFI and do a boost builder program.

The bigger housing wont make more power, a correctly sized housing will make the most power. If its too big to work properly you are leaving HP on the table.
I run a .96 on the 462 and we run a 1.00 on the 106MM in the capri with a 347ci and a 7600 shift point.
Now if the wheel on the S400 is a smaller wheel or a more efficient desgn the 1.32 may work just fine! There are many variables.
Just as a clipped wheel will give a little more top end.

Either way a housing change, is not a big deal unless the parts are scarce.

Mo Money · 10-10-07, 12:58AM

The parts are there, it is a couple hundred $$$ upgrade. A new s400 is only about $600 to start. I'll post a link with the specs.

He already has the NO2 so that is why I suggested it. Been done for years with the ricers.

Here is the link to some specs from TM http://www.theturboforums.com/smf/in...?topic=78417.0

fast72Lemans · 10-10-07, 07:33AM

Quote:

Originally Posted by 71 GrandPrix SJ

fast72lemans- not sure if you remember me but i came up to your house with a couple buddies. one of my friends wanted to by your grandprix you had for sale a couple years ago. he ended up buying an 87 T-Type. anyway i remember your supercharger problems

Small world.......that car is still running, I just saw it 2 weeks ago. I put a vortec 350 in it.......ran 14.60's on radials with the 2.29 open rear.

Just remember.....baby steps with the tuning and check the A/F every run....those are the most important lessons I learned.

turbo69BIRD · 10-10-07, 09:55AM

Quote:

Originally Posted by Mo Money

The parts are there, it is a couple hundred $$$ upgrade. A new s400 is only about $600 to start. I'll post a link with the specs.

He already has the NO2 so that is why I suggested it. Been done for years with the ricers.

Here is the link to some specs from TM http://www.theturboforums.com/smf/in...?topic=78417.0

I agree that the ricers have been doing it but They have to do it.
We have the CI to run a decent sized turbo and have it be optimized.
The price looks good on that turbo The extended tip will bring the RM range down a little.
I would like to find a compressor map on it and do the math to see how it works.
I am also going to check and see what my wholesale pricing is on that turbo maybe I can get it for you even cheaper.

I haven't seen them used at all but that doesn't mean anything There are so many variations with so many differnt names and half are all the same frame etc.

Nitrous and turbos are great together you double your HP level with the nitrous so a 100 shot is a 200 shot at 15 PSI boost!

71 GrandPrix SJ · 10-10-07, 10:06AM

the whole point is to get away from nitrous all together. turbo69 really funny i did a google search on the tv71 and your car came up as one of the first hits! nice car. like i said im doin this in baby steps over the winter. obviously exhaust is first. i am going to use stock manifolds with a crossover pipe. if i can use a turbo that doesnt need the 5'' pipe that would be great or would it just choke it? remember im only going to 5500-5800

turbo69BIRD · 10-10-07, 10:17AM

I use a 5 inch and I reduce it into two 3 inch pipes right off the get go.
I only go 5 for about 2 ft.
The size turbo you need is probably going to use a 5 inch because of the sheer volume of air you need to move through a 462.

At that RPM this turbo runs really well thats where I like to shift my car and it likes it.
There are other turbos you can use but I have used the TV for along time and have had such good results I like to stay with it.
I feel like "if it aint broke dont fix it"
Two smaller turbos witha 3 inch may be the way to go. 60-1's or something like that but your going to double your cost doing that.

You'll be happy with the turbo. They are a fun ride because they make so much power up top. The last 320 ft of the race track is the ardest pulling part of the track.

I always tell people a turbo on a pontiac is like the power band on a CR500 honda
Hang the F*&^ on and hope for the best!

71 GrandPrix SJ · 10-10-07, 10:37AM

ok well i came for advice. ill use the 71 . now how much? you said you were a dealer?

71 GrandPrix SJ · 10-10-07, 11:43AM

Mo dont take it the wrong way! really appreciate your advice as well in the future i just dont wanna go that big. dont feel like pickin my up my crank if something went wrong. start small. this is a budget build BUT i will spend the money on the wastegate and BOV i need and the LM-1

Mo Money · 10-11-07, 03:21PM

No prolem. The tv71 was agood deal when you could find them. Your deal should be ok with a 1.32 exh. The factory logs should keep the velocity up and help spool it. Not having it hit right away may be benificial since you were having traction problems before. Is it ideal? No, but it would help get a turbo under the hood at a good price. How much are the TV71 deals going for now? I was quoted $750 to have my t-6, .96 ex housing upgraded with a T88 type compressor housing. Any thoughts?

71 GrandPrix SJ · 10-11-07, 05:59PM

that looks like the s400 in your signature right? we'll talk more about it on sat. yes i would actually like some turbo lag. i did have problems with traction with 390s and stock stock stock suspension. im talkin not even shocks. but with good slicks did pull a 1.59 60 on motor! which is unreal considering my ET. gotta love that first gear in the 700R4! anyway ive since downgraded to 342s with SSM lowers adj uppers and air bags so im hoping no more probs with traction. if i could still pull low 1.7s on motorand have the turbo come in right around there that would be awesome. just as long is its not gonna start to get going at 5000rpm!!