Question about "low" boosting w/GT35r/SC61

**jrhaile** · 10-26-2006, 06:39 PM

So I think I'm going to pick up a 91 325ix for my winter car/daily driver... black, full maintenace, etc.. really nice and something I have been looking for for a while now! I had basically put aside about 6gs or so for my turbo project and this car is going to cut that money in half. So instead of abandoning my project all together, I'm thinking of starting out with a real base kit - something that I can build on and get back to my normal plans...

I have always wanted to go with a a GT35r .82 for my turbo. Despite some discussion about the SC61 being a good alternative, I think I was going to spend the extra 700 bones and get the big boy! my question is though, how will a Gt35r .82 work in relation to something like 8-11psi on stock compression/internals? Is it just too big of a turbo to do something like that and should I scale down and get something like a SC61? Basically, what would you guys recommend in my situation... keep in mind, this is something that I'm going to BUILD upon meaning adding HG/studs and more and then upping the boost at a later time.

My basic list will look something like this:

GT35r/SC61 turbo
Tial 38mm wastegate 7.5psi spring
tial 50mm BOV
spa manifold
egay intercooler
spal engine cooling fan
42# greentop ford injectors
custom 3" downpipe
custom plumbing
review MBC
etc...etc..etc..

Should keep me around 4gs or so total with a clutch...Titus (dredder) is going to be tuning this...

tia for the input...

**dredder** · 10-26-2006, 07:05 PM

I got the piping done. I should know within next week how much it will cost me to replicate the charge pipe for your current setup without welds.

**jrhaile** · 10-26-2006, 07:34 PM

Originally Posted by dredder

I got the piping done. I should know within next week how much it will cost me to replicate the charge pipe for your current setup without welds.

nice.. I'm hoping to get going on this pretty quickly and I think with a low boost setup like this, I can be done within 2-3 months no problems...

still hoping to hit 350rwhp or so on this setup too... although, with 300+ I would be happy and shouldn't be much of a problem as I'm already hitting 200+

**dredder** · 10-26-2006, 07:37 PM

Originally Posted by jrhaile

nice.. I'm hoping to get going on this pretty quickly and I think with a low boost setup like this, I can be done within 2-3 months no problems...

still hoping to hit 350rwhp or so on this setup too... although, with 300+ I would be happy and shouldn't be much of a problem as I'm already hitting 200+

if you have the funds you should be done in two weeks. or whenever your parts come in

**jrhaile** · 10-26-2006, 07:41 PM

Originally Posted by dredder

if you have the funds you should be done in two weeks. or whenever your parts come in

right yeah, but I have to do things in chunks to hide it from the wife

500 bucks here and there and she won't notice the difference... rofl

I'll need to ask you a couple more questions on AIM sometime soon too...

**dredder** · 10-26-2006, 07:55 PM

Originally Posted by jrhaile

right yeah, but I have to do things in chunks to hide it from the wife

500 bucks here and there and she won't notice the difference... rofl

I'll need to ask you a couple more questions on AIM sometime soon too...

catch me with im on

**m3jasper** · 10-26-2006, 08:27 PM

wouldn't a gt30r be a better fit for the m20?

**dredder** · 10-26-2006, 08:29 PM

he is on m52 with m3 cams

**m3jasper** · 10-26-2006, 08:31 PM

Originally Posted by dredder

he is on m52 with m3 cams

In that case, never mind.

**trthrrt489** · 10-26-2006, 09:33 PM

I've had the 60-1 hifi at 8-10psi and I've had the GT40 at 8-10psi. I like the Gt40!!!! I't comes on a little later, but it is well worth it.

The Gt35R is good from 8-30psi.

**jrhaile** · 10-26-2006, 10:29 PM

Originally Posted by trthrrt489

I've had the 60-1 hifi at 8-10psi and I've had the GT40 at 8-10psi. I like the Gt40!!!! I't comes on a little later, but it is well worth it.

The Gt35R is good from 8-30psi.

You get your stuff from cheapturbo.com? That's where I'm thinking of buying their package deals...

**trthrrt489** · 10-26-2006, 10:42 PM

Originally Posted by jrhaile

You get your stuff from cheapturbo.com? That's where I'm thinking of buying their package deals...

Yep, I got the 60-1 used, but the GT40 was from Cheapturbo. I added the wet center and got an oncenter turbine housing.

**jrhaile** · 10-26-2006, 10:45 PM

Originally Posted by trthrrt489

Yep, I got the 60-1 used, but the GT40 was from Cheapturbo. I added the wet center and got an oncenter turbine housing.

I e-mailed them asking about getting the GT35r .82 for that deal... what's the difference between the 40 and 35? And what in the hell is a wet center and oncenter turbine housing?

edumucate me por favor

**ICS Performance** · 10-26-2006, 10:56 PM

Originally Posted by trthrrt489

I've had the 60-1 hifi at 8-10psi and I've had the GT40 at 8-10psi. I like the Gt40!!!! I't comes on a little later, but it is well worth it.

The Gt35R is good from 8-30psi.

GT40r is a great turbo, much better than the GT35r hands down....

**jrhaile** · 10-26-2006, 10:57 PM

Originally Posted by IMPORTEDCARS

GT40r is a great turbo, much better than the GT35r hands down....

wow, really? How long would it take to spool do you think with a decent tune on a M52 OBD1 w/S52 cams... stock compression and internals?

**trthrrt489** · 10-26-2006, 10:58 PM

Originally Posted by IMPORTEDCARS

GT40r is a great turbo, much better than the GT35r hands down....

I don't have the 40R I Just have the GT40, but I am wishing I had gotten the 40R.

The wet center is just a section that you can hook up coolant lines to run the turbo cooler. The on-center is a older style of turbine housing that I am almost forced to use because of manifold placement.

The New Garretts alsmost all use tangtial housings. The have a better flow.

**jrhaile** · 10-26-2006, 11:00 PM

Originally Posted by trthrrt489

I don't have the 40R I Just have the GT40, but I am wishing I had gotten the 40R.

Inform me, what's the difference in the GT40 and GT40r? Same goes with the GT35r I would imagine right?

**David_L** · 10-26-2006, 11:01 PM

Since your talking M3 cams, Can I put those cams in my 2.5?
I was so close to buying a m3 engine/trans(manual) combo last night but I think I want to see what I can do with my 2.5 first.
Anybody?

Back On Topic, Looking forward to watching this build.
Thanks

Originally Posted by jrhaile

Inform me, what's the difference in the GT40 and GT40r? Same goes with the GT35r I would imagine right?

I think it has to do with the ball bearing setup. Not sure though?

**jrhaile** · 10-26-2006, 11:05 PM

I'm looking forward to it too...I already bought xmas gifts, so no other major expenses in the coming 2 months

**ICS Performance** · 10-26-2006, 11:06 PM

Originally Posted by trthrrt489

I don't have the 40R I Just have the GT40, but I am wishing I had gotten the 40R.

On a built motor, 8.5 compression mild tune via TEC3r 11 degrees timing on ramp up, full boost before 4k, and over 600rwhp, and equal torque on pump fuel... I havent ryed it on a stock motor yet.

**David_L** · 10-26-2006, 11:08 PM

Originally Posted by IMPORTEDCARS

On a built motor, 8.5 compression mild tune via TEC3r 11 degrees timing on ramp up, full boost before 4k, and over 600rwhp, and equal torque on pump fuel... I havent ryed it on a stock motor yet.

need a donor?

**///36M** · 10-26-2006, 11:32 PM

Originally Posted by IMPORTEDCARS

On a built motor, 8.5 compression mild tune via TEC3r 11 degrees timing on ramp up, full boost before 4k, and over 600rwhp, and equal torque on pump fuel... I havent ryed it on a stock motor yet.

hmmm is this "too much" for someone going built but w/stock rods (s50 engine) and planning to tune stock dme for now (basically for a year or so, until techno figures out if he can tune to 600whp or I go Tec3)

aka 400-450whp for a yr or so, pushing boost later.

Realize its a roundabout question, but....?????

**Juicy Double** · 10-27-2006, 01:41 AM

if all you want is 350-400whp, I don't see the point to the gt35R or the gt40r.

**fritzintn** · 10-27-2006, 02:58 AM

I'm not sure I really understand (or see) the question.

The GT35R and the SC61 both have fairly high flow rates, but I wouldn't be too concerned with having the 38mm wastegate keep up. I'm using a Tial 44mm and feel it's a bit of overkill.

Search for 'boost creep' and you'll find a number of threads detailing wastegate dump tube placement and thoughts on overall wastegate size.

If the intent of the thread was 'look what I'm going to do', then well it looks fine to me. The only thing I would suggest is going larger with the injectors from the start and rethinking the blow off valve if you are going to use the HFM based tuning from Dredder/Techno/etc since it will need to be rerouted post HFM of you'll have funky a/fs between shifts.

I also think your budget is a bit optimistic as well. The clutch and turbo alone will have you north of $2k.

**dredder** · 10-27-2006, 07:14 AM

Originally Posted by BoostBoards

Since your talking M3 cams, Can I put those cams in my 2.5?
I was so close to buying a m3 engine/trans(manual) combo last night but I think I want to see what I can do with my 2.5 first.
Anybody?

Back On Topic, Looking forward to watching this build.
Thanks

I think it has to do with the ball bearing setup. Not sure though?

Keep your 2.5, install the m3 cam and reap the power without buying the 50/52 block

Thread: Question about "low" boosting w/GT35r/SC61

Thread Tools

Question about "low" boosting w/GT35r/SC61

Bookmarks

Bookmarks

Posting Permissions