Thinking of going turbo, need some suggestions.

92bird

Registered User
I'm thinking of going turbo on my '94 SC. It is completely stock except for a built 2003 mustang 4R70W, and mach 1 torque converter.

I can mig weld very well, and have fabricated several exhaust systems from individual mandrel bends on several different cars. I have access to a TIG welder as well for aluminum IC piping fabrication.

My plan is to start with a refreshed '91 SC shortblock (8.2:1 compression), with the '94 windage tray and oil pickup, MLS gaskets, and head studs, and the '94 SC cam as I feel it is better than the early model cams IN A TURBO application.

The turbo I am looking at running is a single Borg Warner S256 w/extended tip, and using a Tial 38mm external wastegate.

The goal of this project is 350whp on a stock longblock, fast spool, and good drivability. Not looking to win any awards for "highest HP" or fastest 1/4 mile times.

Why do this? I made 345.5 rwhp and 402.8 rwtq on my old M90 setup?? Am I stupid? Well, no.. Lets add up MP blower, inlet plenum, big cam, springs, ported heads, SCP headers, pullies, big TB, big MAF, yadda yadda yadda.. Not to mention poor gas mileage to boot.

I think for much less than the cost of those things, I can make my own streetable turbo kit that will be fun to drive daily, and just as fast, if not faster.

I'm thinking of fitting FWD 3.8L (taurus, windstar, etc) center dump exhaust manifolds, bringing the downpipes forward (2 or 2.25"), and making a custom upper intake to bolt to the existing SC lower, with an adapter to utilize the factory EGR (we have smog tests here in CO)..

Also may go Precision T61 turbo, but I think the S256 will spool better and more than be able to meet my daily driver horsepower goals.

Thoughts? I'm thinking it will be a fun winter project.

With an uber quiet exhaust, i think she can be a sleeper.

Jeramie
 
If you are refreshing the block I'd attempt to do some improvement on the heads and change out the bump stick to something more aligned for a turbo application.

Remember with whatever you cook up you'll have to address A) Fuel B) Tuning. allow budget for that. Other things you'll have to think about is space for the turbo and what you'll do for an intercooler.

I have no doubt you'll be able to do it. :cool:
 
I've still have the EEC tuner I may rob from my '92, or I may do an SCT chip eventually.

Since the '94 already has bigger 36lb injectors, I had thought about starting out with the stock tune, and just keeping the boost turned down at first. Honestly, with a small efficient turbo like the S256, I bet I could match stock SC RWHP numbers on only 5 or 6 psi. The smallest wastegate spring I can get is 4.4psi, that may be the ticket for an initial testing period.

Its more about the challenge for me, I like thinking out of the box. Making this turbo kit will be just as fun as driving it when its done :)

A couple grand prix GTP guys have hit over 400 whp on a stock engine with this turbo, and that configuration is limited to a 2.5" downpipe due to packaging concerns.

Also, I can sell the '94 blower and plenum which I recently rebuilt, and regain some of the cost of the turbo parts.
 
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Damn, how did I miss that thread?? LOL.. I searched, I swear..

That is a good idea.. I know the combustion chambers are more efficient on the split port heads too.

Does anyone know the combustion chamber volume on the split port heads? I was wondering what type of compression i'd end up with, using the SC bottom end and split port heads?
 
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I'm thinking of fitting FWD 3.8L (taurus, windstar, etc) center dump exhaust manifolds, bringing the downpipes forward (2 or 2.25"), and making a custom upper intake to bolt to the existing SC lower, with an adapter to utilize the factory EGR (we have smog tests here in CO)..

Do you have visual tests? LOL.
 
They do visual for cats, and EGR in place, other than that, as long as it passes the sniffer they don't care. You can put in whatever engine/modification you want, as long as the end result meets the emissions requirements for the original factory installed engine.

Another reason I want to try to make bigger power with a stock cam, when I had the .520 cam, it ~barely~ squeaked by colorado emissions, and they just got more strict this year.

For those of you who do not have emissions testing, be very appreciative of that. It sucks.
 
Not saying you cant do it, but I think that using the SP heads and factory intake would save you a ton of time and money. Not to mention, look at Corey's car....It looks factory!! My vote is for that as well....
 
if your going to rebuild the short block be sure you slap in some forged pistons minimal and it wouldn't hurt to up the compression a tad, 9:1 would be nice

70mm turbo is about perfect with a .82 housing, more than enough power to make most happy

don't skimp on junk get a tial bov and w/g

split port heads would be ideal, if you kick open the exhaust in them they make some power, on the intake they outflow most well ported/big valve sc heads being bone stock, exhaust is the big problem on them though, so prepare to spend some bucks either way

I do ford efi tuning in new orleans, when you cross the ecu road shoot me a PM, I'll see what I can do for you
 
I'm thinking of going turbo on my '94 SC. It is completely stock except for a built 2003 mustang 4R70W, and mach 1 torque converter.

I can mig weld very well, and have fabricated several exhaust systems from individual mandrel bends on several different cars. I have access to a TIG welder as well for aluminum IC piping fabrication.

My plan is to start with a refreshed '91 SC shortblock (8.2:1 compression), with the '94 windage tray and oil pickup, MLS gaskets, and head studs, and the '94 SC cam as I feel it is better than the early model cams IN A TURBO application.

The turbo I am looking at running is a single Borg Warner S256 w/extended tip, and using a Tial 38mm external wastegate.

The goal of this project is 350whp on a stock longblock, fast spool, and good drivability. Not looking to win any awards for "highest HP" or fastest 1/4 mile times.

Why do this? I made 345.5 rwhp and 402.8 rwtq on my old M90 setup?? Am I stupid? Well, no.. Lets add up MP blower, inlet plenum, big cam, springs, ported heads, SCP headers, pullies, big TB, big MAF, yadda yadda yadda.. Not to mention poor gas mileage to boot.

I think for much less than the cost of those things, I can make my own streetable turbo kit that will be fun to drive daily, and just as fast, if not faster.

I'm thinking of fitting FWD 3.8L (taurus, windstar, etc) center dump exhaust manifolds, bringing the downpipes forward (2 or 2.25"), and making a custom upper intake to bolt to the existing SC lower, with an adapter to utilize the factory EGR (we have smog tests here in CO)..

Also may go Precision T61 turbo, but I think the S256 will spool better and more than be able to meet my daily driver horsepower goals.

Thoughts? I'm thinking it will be a fun winter project.

With an uber quiet exhaust, i think she can be a sleeper.

Jeramie

Jeramie,

This guy is selling a low mileage PT61 that would be just right for an SC motor like you are describing, and will allow room for more power later, when you get bored with 350 rwhp.

http://www.v6power.net/vb/showthread.php?t=45915

David
 
Any thoughts on a Holset HX35? I found one locally for $300. I hear they have a pretty wide efficiency range, and are pretty durable.

I have a friend that is using one on a built big valve 2.3L turbo Merkur.
 
Been thinking about the split port swap.. I think I really want to stick with the complete SC engine. I've got to keep the cost down.

The '94 has had slight rod knock ever since I got it, and I have a '91 SC engine that has been refreshed that I could put in.. Typically seems that lower compression is favored for turbos that make higher boost levels more efficiently.

I'd have to swap the front covers and balancer to put it in the '94, which is why I considered swapping the '94 cam over to it as well since i'll have the front off.

I'd really like to see what I can get out of a stock longblock SC. I'm using this as my DD, since my GTP is running on E-85. Gas mileage and drivability take priority over peak hp.

I'm still learning about turbos, and still don't have the knowledge to figure out which type to get. A guy i work with suggested a GT35R ball bearing turbo, and another guy suggested a Holset HX35 twin scroll, which I could feed 3 cylinders into each scroll..

I'm not too worried about being limited on power, The car will remain internally stock. Been down the road before with cams, ported heads.. I just want to throw some turbo-charged boost at it through a good IC and see what it does. :cool:

I have an idea in my head for piping that will allow me to keep A/C.. It is working in my head, we'll see if it works in real life or not. Taurus manifolds are out of the question.. it hits the steering shaft..

Jeramie
 
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Jeramie,

I don't know enough about those other turbos to be of any real help, but I think Ryan R. is using a ball bearing GT35 and it spools super quick and makes more power than you are after, so it's probably another good choice. Best to contact him directly for details on the turbo. Here's his profile link.

http://www.sccoa.com/forums/member.php?u=1578

Also suggest doing lots of reading and then posting your turbo size questions in the Newbie Turbo tech forum of this website.

http://www.theturboforums.com/smf/index.php

David
 
Plan it out well before you start, I got in way over my head. I probably have over a grand in parts I just didnt think of. Hole saws, vac, line, an fittings, it all adds up. Good v bands are very expensive as well as many other turbo related parts. Good luck, turbo cars are fun, just ask David N and the other guys.
 
Here's a link to the compressor maps for many of the Turbonetic turbos.

http://www.turbocharged.com/catalog/compmaps/t61.html

This link goes directly to the T61 you're asking about, but the rest are at the top. You might want to look at the T60-1 as well. If I remember correctly, I think this is the turbo I thought would work best for a daily driven SC when I was researching this a couple years ago, but it may have very well been the T61. All I know is a T, 6 and 1 were in there. LOL

Keep us up to date on the build!

Edit: Be sure to do the math. Dalke posted some info on what he believed the BSFC of an SC motor to be on here in the past. This may have changed, but that's one of the numbers you'll need to calculate the best turbo to use for your application.
 
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I have an idea in my head for piping that will allow me to keep A/C.. It is working in my head, we'll see if it works in real life or not. Taurus manifolds are out of the question.. it hits the steering shaft..

Jeramie

Did you try flipping 'em?
 
Wow, thanks for all the info guys. I've got a ton of reading to do.

I really want to do this, and have the fabrication skills to do so.

Those stupid A/C lines are really in the way though..

My latest plan I think is going to be a downpipe off of the passenger side manifold, running under the bellhousing and T-ing into the driver's manifold in their original positions. Then bringing the hot pipe out under the power steering and positioning the turbo where the factory IC went, and sticking the air filter where the battery went (relocate battery to trunk), then run the turbo outlet under the rad fan, and around under the passenger side bracket out to the rear.

Any opinions on a blow through MAF or should i just relocate it to the inlet side of the turbo?

This is fun.. I want to start welding already :D
 
Wow, thanks for all the info guys. I've got a ton of reading to do.

I really want to do this, and have the fabrication skills to do so.

Those stupid A/C lines are really in the way though..

My latest plan I think is going to be a downpipe off of the passenger side manifold, running under the bellhousing and T-ing into the driver's manifold in their original positions. Then bringing the hot pipe out under the power steering and positioning the turbo where the factory IC went, and sticking the air filter where the battery went (relocate battery to trunk), then run the turbo outlet under the rad fan, and around under the passenger side bracket out to the rear.

Any opinions on a blow through MAF or should i just relocate it to the inlet side of the turbo?

This is fun.. I want to start welding already :D

You would have to find some other manifold lines to work and go from the compressor around and behind the upper intake. I think something similar to what is on the 87-91 F-150/Bronco. They actually went around the intake like that and were hooked to the cowl....I know....budget build, but you will thank yourself. Especially with the underhood temps that thing is going to create....Probably need a condensor with the inlet and outlet on the driverside too....
 
Thinking outside the box here. Since you have welding skills and the equipment. Do radical modifications of the intake manifold (like cut the center out of it). Locate the turbo in the engine V, this should accomodate a short exhaust path short for quick spooling.

Then throw in a liquid to air IC at the outlet of the turbo to keep the intake piping short.

The V-8 turbo diesels put the turbo in the V and the intake manifold(s) are a sheet metal fabrication that bolts to the heads. If you were to go this route, a valley pan (cover) AKA old Pontiac V-8's would have to be fabricated, along with a water outlet and thermostat housing.

OK so maybe way outside the box.
 
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