[quote]Originally posted by ribs:
<strong>Mistubishi turbos are apparently the fastest spooling turbos (just the opinion of a friend of mine who owns an import shop and does a lot of turbo applications) but do not flow as well as turbonetics turbos for the size.
</strong><hr></blockquote>

Sounds pretty silly. Spooling has a lot to do with proper sizing. Sizing has many variables, not just the physical size of the wheels/housings.

[quote]Originally posted by ribs:
<strong>Any brand of turbo will work, you just have to have the flanges on your piping mated to the flanges on your turbo, which any exhaust shop should be able to do for you. </strong><hr></blockquote>

Any brand may or may not do. Selecting a turbo is not something you should do casually. You certainly don't just go pick up a turbo and slap it on unless you want poor performance.

 

[quote]Originally posted by FSTPRSH:
<strong>Okay, if I can get some maps, what models of turbos are compatible? Will just any do, or certain kinds?</strong><hr></blockquote>

Well, I'm not sure what you are talking about. If you are simply talking about what will mount up, I don't know. You probably will need some adapter made to go from your stock header to actually mount the turbo.

If you are talking about what turbo to run, you'll have to do some homework.

Here are some recommendations from Mike's SCC article:

For a fast spool custom turbo, consider:

Garrett T3, 60 trim T3 C wheel, .48 a/r T3 C housing, 72 trim T3 T wheel, .63 to .82 a/r T housing

Garrett T3, 62 trim T3 C wheel, .60 a/r T04B C housing, 72 trim T3 T wheel, .82 a/r T3 T housing

For a fast spool off-the-shelf turbo, consider:

HKS GT2835, .86 a/r exhaust housing, dual ball beearing center section

For a max street performance, weekend warrior combo custom built turbo, consider:

Garrett T3/T4 Hybrid, 60 trim T04E C wheel, .60 a/r T04E C housing, 76 trim T350 T wheel, .82 a/r T3 T housing

C = Compressor
T = Turbine

These are guesstimates based upon displacement of 2200cc to 2600cc. These would be a good place to start for trying to find maps. I personally wouldn't just grab one of these and slap it on. The vendors who are offering the SC kits have done their homework and the engineering to provide a good package. If you want a better package, you need to do your homework.

 

[quote]Originally posted by Geo:
<strong>
Sounds pretty silly. Spooling has a lot to do with proper sizing. Sizing has many variables, not just the physical size of the wheels/housings.
</strong>

I know this...maybe I could have clarified my statement more, but I didn't realize I would be called silly. Geez. What my pal with the shop told me is that for similar compressor and turbine trims/housings, the mitsubishi turbo is designed to have better response and spooling time while sacrificing total flow as compared to, say, a turbonetics turbo. Its all in the engineering, but I am not an engineer...I was just sharing an opinion of someone that I believe to be knoledgable. Silly...pfft.

<strong>
Any brand may or may not do. Selecting a turbo is not something you should do casually. You certainly don't just go pick up a turbo and slap it on unless you want poor performance.
</strong>

Geez man...its seems like you are trying to make me sound like a moron. I did state eariler in my post that "I don't know if they have them in different trims that would be suited to your motor though". I know that you have to match your turbo's turbine and compressor to exhaust flow rate and how much air you plan on forcefeeding the motor at a given pressure. Compressor maps are essential in doing this. I left out the thing about matching your turbine/compressor sizes to the motor because you touched on it earlier and I thought it was implied. You can get custom trimmed turbos from most (all?) turbo manufacturers, and in doing so would be able to select from your favorite brand...I was merely stating that if you can match the turbo to your motor from any brand, that it can be bolted up with a little custom exhaust work...so there.


<hr></blockquote>

 

Geo, you said that it was a gurestimate for a 2200-2600cc engine...I'm looking more around 2900-3200cc's. Do you know where I can get a copy of that article? I'd like to come by a 3.0 turbo and rebuild it. It would go all the way down to bare block and be built part by part...so if anyone knows where one might be, preferably lying around in a car at a junk yard, or actually all I need to have is the block and head. Any leads? Thanks for all the info.

 

My opinion is still supercharger to keep it simple. Rennlist Member Tholyoak has a <a href="http://members.rennlist.com/tholyoak/callaway.html" target="_blank">Callaway</a> turbo kit just like mine. His is actually one of the THE CallawayTurboSystems 944. They were all '83, as far as I know. It is simple compared to the factory turbo setup, but does not allow you to run anything bigger than a T3 sized turbo due to room limitations, hits the frame. The kit used an IHI RHB6 turbocharger. This is my kit before I installed it. If you go with turbo, your cheapest best bet is the parts and you have to stick to a stock KKK or a proprietary(sp?)turbo from SFR, HR, ect as it uses different turbine flanges and the oil return tower flange that mounts and supports the turbo is different than the Turbonetics/Garrett. This crossover pipe is Broadfoot Racing, and they were asking $1500 from the head to the turbo. I think Tim/SFR is building a similar unit that is also cheaper cost.

 

[quote]Originally posted by FSTPRSH:
<strong>I've seen a lot of blowers (superchargers) and have yet to see one that doesn't require a bigger cam to get back the horsepower it took away.</strong><hr></blockquote>

Start with every single bolt on supercharger for newer hondas. Then look at the SFR supercharger.

Note: EVERY force turbo/super charged engine will make more HP with a cam designed for forced induction.

 

[quote]Originally posted by ribs:
<strong>I know this...maybe I could have clarified my statement more, but I didn't realize I would be called silly. </strong><hr></blockquote>

[quote]Originally posted by ribs:
<strong>Geez man...its seems like you are trying to make me sound like a moron. You can get custom trimmed turbos from most (all?) turbo manufacturers, and in doing so would be able to select from your favorite brand...I was merely stating that if you can match the turbo to your motor from any brand, that it can be bolted up with a little custom exhaust work...so there.</strong><hr></blockquote>

Ribs, sorry I misunderstood. It just sounded like you were over simplifying. Sorry if I got the wrong impression.

 

Do not get me wrong.I know that a properly sized turbo will make more power then a properly sized SC. the main difference is that the SC is driven off of a belt and it is not limited in size for the most part like a turbo.You can run that big SC on a small displacement motor and not get the lag you would if you tried to run that big turbo on a small displacement motor.

What the original thread was about was that turbocharging is a better way to go on an 8 valve N/A! With the turbos that are available that will work with the existing 951/944 parts.........you cannot compete against the supercharger we are using. You just cant. The SC we are using can flow in excess of 1200 cfm without turbo lag. Granted its not flowing that much at 6 or 8 psi of boost but I can tell you it flows more then any turbo you can bolt-on to the 951 at the same boost level. What turbo can you get for the 951 or an N/A conversion that can flow that much air and not have a huge amount of lag? There isnt one. The big difference now is that you can run a very large supercharger on a small motor and still make more power.You cant just run a really large turbo because you have to deal with turbo lag.

Now lets state some hard facts.......Our supercharged N/A conversion makes 182 horsepower at the wheels which is the same as a stock 951.The main difference is that we used no intercooler and we ran about 6 psi less boost yet we ended up with the same horsepower numbers......Throw an intercooler in the mix and turn up the boost a few psi and now our supercharger made 222 at the wheels(which is 30 more rear wheel horsepower then a stock 951) and is still running less boost then a stock 951.Now which is the better alternative for this application? This was my main point. Both superchargers and turbos are great power adders but one might be better then another for certain applications.


As far as converting a 944,968 to turbo.....it is definitely not as easy as doing a bolt-on supercharger.The supercharger is a bolt-on that requires no hacking or welding....the 968 to turbo conversion requires all sorts of parts to be cut and welded. Definitely not the easiest thing to do. I mean you have to fuse an aluminum 968 intake manifold with a 951 intake manifold! This is the simplest thing anyone has ever done? Cant do this with your DC box welder from Home Depot so it is not as easy as you might think;^) Now you have to cut up and weld the exhaust. Next you have to tap an oil feed from the upper balance shaft and relocate parts like the idle stabilizer,etc.....The next part of the eqaution is rounding up 15 or so 951 parts to finish the conversion and figuring out how to control fuel, boost and timing. By the time someone rounds up the parts for the conversion(forget all the welding,tapping,etc... that is involved) I have a supercharger bolted to the 944,968 and I am driving away:^)

Tim
86 951
<a href="http://www.speedforceracing.com" target="_blank">http://www.speedforceracing.com</a>
619-441-1359

 

968 turbo conversion, by far the easiest mod we have done, bolt in the parts, run 951 this and that...bam, 60 hp at the wheels improvement, no detonation.

944S2/968 Supercaherger conversion, issues,


I think that statement is going to discourage people from thinking about an SC kit when..... it is the best alternative out there for their 968 and there is no issues. Its not like we have to cut apart a 951 intake and fuse it together with a 968 intake. What about modifying a cross-over pipe? Those are 968 turbo conversion issues that have to be addressed.


but not something that cannot be completed by a good shop.


Actually it can be completed at home if you have a socket set and some wrenches. Most enthuisiaists should be able to do it in a few hours. You dont need to touch the intake manifold or exhaust either;^) Its a very simple conversion. You know this. You take the old parts off, you put on the new parts, install the chip, you are done. Thats it. A couple of hours tops.


Many upgrades to the induction, 993 type MAF sensor, custom wiring, custom chips.


The only upgrade is to the sensor.Yes you need a custom chip and you might need one for your turbo conversion too. There is no custom wiring involved. You are taking what you have experience with(the S2 SC system) and applying it to the 968. They are two different cars with different concerns to address.

 

Tim, I didn't mean to ruffle your feathers! I was just speaking from experience.

Yes you are helping us with the fabrication of the 968 project, we announced that the day we began on the 968 list. We appreciate your work on this with us.

I was not attempting to cast doubt on the SC kits, remember...although I'm not a part of your business anylonger, its still a pet project that you and I started together, and its a project I believe strongly in...I know for a fact its a good product, and a great kit.

As for my Turbo conversion kits, well, thats another project that I believe is a great product. No longer does this conversion mean you have to pay big bucks, I'm trying to get a point accross, it is not a 20,000 dollar conversion. Even dropping lower compression pistons yadda yadda does not bring the conversion any where near what people have been charged for in the past.

It is quite simple, the only two things that have to be custom built, is the intake manifold (we are keeping a stock look with the 951 intake, and using the runner from a 16 valve, only for the look...you and I know it would be easier still, if we just made our own plenum)and the crossover flanges must be rotated.

Tapping an oil line? The feed is already blanked on the balance shaft cover, the oil drain is already plugged on the pan, We use the stock oil feed line and drain line from the turbo.

The water lines are already there also. If you look at the plumbing, you can see clearly the water feed to the turbo water pump is there on the 968, just like the turbo, and the radiator has the other line plugged off, we simply un plug it and run the line.

We will keep the stock intake, MAF etc etc, you don't loose any of the plastic in the hood area, the glove compartment stays intact.

We are only running 4psi boost, simple Adjustable FPR will do the trick for fuel, the injectors are perfect.

So, in short, it is simple :-) And will be reliable also. No boost controllers, just a wastegate with a light spring, run from the manifold.

Low cost, simple, reliable.

Sorry if I came off like I was bashing your kits. I would not do that. YOu do good work, and the kits show it :-)

Take Care

 

John,


Its cool man. Both of these kits are going to have their advantages and disadvantages. It seemed as though the turbo guys have the advantage on this post;^) I am truly a turbo guy too. I just wanted to point out that the bolt-on supercharger for the 944/968 series cars is now a reality that should not be dismissed. I will talk to you soon.

 

supercharger kits are far more easier to put together then turbo kits....

i know for my subaru, they made a rimmer kit....all it was:

SC
brackets
IC
pipping
FPR

that was it....althought the quality was poor, and most had to get the mountings refitted anyways(one of the reasons rimmer is out of business) the kit was fairly simple to put together....depending on the year of 2.5 RS you had, you may of needed to get a air fuel controller but with the 2.5 rs i have....i wouldnt of needed it....i know there is another company down in NC putting together a kit for the 2.5RS...its basically going to contain the same componets as the rimmer kit....

even the rimmer kit i had for the 944 before selling it to my944 was simple....it had the SC, Intake manifold, aquamist injection, the intake pipe for the SC that the throttle body fit on, and the oil feed lines....pretty simple....

the best thing about these kits is the fact you have no lag....on my subaru with AWD...no lag, those cars have good torque, lots of fun, especially between stop lights ....i want one now...

with the turbo kit i was looking at for my scooby:

up/down pipes
turbo
wastegate
brackets
pipping
IC
fpr

even though it would of probably be as simple to put on the car, there was alot more involved in making it.....the price was more then the sc kit too.....of course that company took everyones money and ran....they went out fo business too....but i was lucky and got mine back....

personally, i would take a SC over a turbo....especially a centrifugal....you can reach higher boost with those....right now im going to get the highest i can get then as soon as i get a engine management kit, im going to shoot for 25 psi....dont know if that will be possible to get since pulley sizes may limit me (one advantage on turbos) i will try my best....

anyhow i just thought i would share my thoughts on turbos and SC's....hope no one minded....im still recovering from that bachelor party i threw <img src="graemlins/drink.gif" border="0" alt="[cherrsagai]" /> <img src="graemlins/c.gif" border="0" alt="[ouch]" /> ...probably rambling....

space

 

With the custom crossover pipe, you can mount any turbo to it, T3/T4, To4E/S/X, IHI RX6, ect as they can weld any turbine inlet flanges to it, but the shaft housing/CHRA to motor mount tower/oil return may still be the problem.

 

This is what you need:
--Turbo Transmission
--951 (turbo) engine
--Bell housing from front and rear of a 951
--Tourque tube 951
--Intercooler
--Rear suspension mods (951 most likely) 968 may possibly work too
--Brakes from 951 or Aftermarket
--Turbo radiator
--Turbo starter
--Turbo computer
--Full Exhaust (turbo or aftermarket)
I have also heard that you will need a full wiring harness as well but I dont know if that is needed if you get an aftermarket boost controler. Also depending on your needs you may want a new dash for different gague cluster.

Im doing this same project as well and thats what ive needed so far. Personally Im buying a built 951 engine instead of rebuilding it myself because of the other mods Ill be doing. Huntly racing has a nice setup.

 

And Space, how would you manage to get to 25 PSI? Aren't the pulleys that you got maxed out already?
Which unit are you running, the P1SC or D1SC? Don't take my word for it, but at those kind of pressures, it would be close to
650-700hp, and I am not sure if the 2.5L engines can safely and reliably put that much power out.