turbo charging a 3.2 - question for all turbo goru's...

dickster · 02:08 PM

not having any cash will do this to a guy.

determined not to leave the turbo route heres my idea.

buy a whole bunch of turbo gubbings off an old 930. turbo unit, wastegate, intercooler (possibly use custom to fit under lid), muffler, valve covers, oil lines, and all pipe work etc - all secondhand of course.

disgard old 3.2 cat. or cat bypass, and muffler.

slap on turbo kit, adapting sheet metal and pipes as necessary - shouldnt require too much fab, as most stuff should be a direct bolt on??

alter wastegate to limit boost to 5psi (to avoid having to piss about with ignition/timing).

add a rising rate pressure regulator to supply (precalculated) additional fuel requirements under boost conditions only.

set up on dyno. and thats it. a cheap route into turbo heaven for us NA guys.

i've tried a search ( i remember seeing something) but couldnt find anything.

what do you guys think (you guys that are building your own systems)? am i missing anything here?

how well will a std 930 turbo unit work with low boost levels?

btw - no smart ass comments on my sloppy spelling. i have had a couple ok

5axis · 05-24-2003, 04:35 PM

I think Juan is going to be your man on this one. Your best bet might be something like recreating the promotive kit. Good luck. The boost bug is contagious

beepbeep · 05-24-2003, 05:26 PM

930 turbo is prehistoric unit...it would be bad choice in your application. If you are only planning to run moderate boost, i think it's much wiser to buy more modern second-hand unit with integrated wastegate. Not only will it save you from the hassle with clumsy and expensive separate wastegate, it will also spool up much quicker than shoddy KKK 3DLZ.

Your car already has EFI, which makes it easier to fiddle with those things.

I think Mitsubishi TD04-18G would fit your bill. When it comes to EFI, you could probably ditch your Bosch unit and replace it with Megasquirt, for approx. 100$ in components and some soldering.

This approach requires that you know little about turbocharging in general. Judging by your initial choice of components, you don't :-) , so it might get expensive on the end...

dickster · 10:38 PM

beepbeep,

what model is the Mitsubishi TD04-18G fitted to?

whats the std boost pressure limited to? can it be easily modified to limit to 5psi?

not sure what you're getting at with the bosch stuff. is "megasquirt" a regulator??

the idea was to use std "porsche" parts to enable straight swap and keep cost down.

thanks for the comments - noone else got any??

btw - i admit my knowledge isnt excessive (or practical) but i have done "some" research

Natchamp · 05-24-2003, 10:48 PM

Dickster, I agree with Beepbeep. You'd be better off with newer technology. You first need to establish a budget amount you want to spend and go from there. Secondly, buying used turbo parts will sometimes just get you used up equipment. These components live a very hard life and don't last forever.

05-25-2003, 12:15 AM

There is no such thing as cheap and easy turbocharging.

beepbeep · 05-25-2003, 04:33 AM

TD04 sits on various turbocharged cars...off the top of my head: Volvo 850 Turbo, S/V70 Turbo, SAAB 9000 Aero etc. There is no "standard boost pressure", it's limited to whatever you adjust wastegate to.

930 parts won't bolt straight, aren't cheap and won't work well when used with low boost. Just forget it.

Megasquirt is DIY ECU...if you don't know what ECU is i suggest you not to use it, but to ask someone to reprogram your Bosch unit with bigger injectors.

There is indeed such thing as cheap turbocharging, but you need to know what you are doing and do lot's of work yourself...

dickster · 05-25-2003, 06:40 AM

thanks for all the advice guys.

i dont feel that i have the necessary skill (or patience) to fab the pipework etc myself - hence the use of 930 pipework (will that not bolt straight up ???).

if the idea is not feasible/workable then £3k on the proto stage 1 kit seems like the sensible option - only i aint got any cash at present (shame with the exchange rate so good). i cannot see any point wasting time/money on another route - it seems like you're not gonna save much at the end of it.

rick conrath · 05-25-2003, 08:08 AM

Forget making your own EFI controller, you will spend time just trying to figure out if you made it right when something goes wrong.. I would try to get an exhaust setup off a later model twin turbo and go from there. I am mocking up a twin setup using the 993 exhaust as the starting point, with the Carrera injection system. In some respects it's just an exercise in plumbing, but its not cheap and it takes time to get all of the parts together. I am already starting with a 3.3, so my jobs a little easier since I don't have to crack the case and change out pistons. By the way...my prehistoric unit is still running strong after 25 years. We'll see how EFI fares over the next year.
Rick
'78 930

bell · bell's Garage

also all turbo dodge T-II setups use the garret td04, try checking www.turbododge.com in their classified section for misc used turbo parts.
also many junkyards will have early/late T-I setups you can get cheap......the T-I's used the garret td03 which may be better for faster spoolup with lower boost pressure.....IMO.

dickster · 12:22 PM

rick,

sounds great - you're doin twins?

bell,

i had a look thanks. problem is matching the unit to a 3.2 engine. without maps its pretty hit and miss. thats why i thought use the unit porsche used to start - cant go wrong. most on the site seem to be for 2.5 liter motors - bit too small. i know that a good 1.8 liter motor could be the source for 2 units for a twin set up but thats getting too serious for me.

question is why do guys rave about 930's (including old ones with oe turbos) but slate the old turbo units?? they cant be that bad can they? especially compared to not having one at all.

beepbeep · 05-25-2003, 12:46 PM

Euro SC exhaust should be pretty similar to 930 exhaust, so you could just cut it after Cat/pipe and re-route it into turbocharger.

Of course, you can use 930 turbocharger (KKK 3DLZ) but there is no point as it has fairly high boost treshold and is pretty laggy.

Matching the unit isn't so critical, turbo that boosts 1.5 bar into 2.5L engine will flow more air than one boosting 5 psi into 3.2 engine....get my point?

Talking about 930 parts...only thing you could use straight-on is probably exhaust manifold. Intake is different, CIS is different (compared to your Motoronic), interooler is missing in your car...almost everything is different.

I think you have a naivé vision of taking the 930 parts and just bolting them to your engine and somehow it will produce lot's of power. It doesn't work that way...

Original 930 has very low C/R (6.5 to 7.0:1), CIS injection, big turbocharger and pretty high boost (~10 psi)...so its quite different from your engine. That's why you need to adopt different approach to turbocharging.

But if you cannot weld things yourself, don't know how it works and just want to bolt turbo on it for 3k£ i think it's better idea to look for used 930 engine instead...

dickster · 01:42 PM

beepbeep,

doesn't the 930 have the two heat exch. going into one as per 3.2's? the sc's have the two heat exch going diretc to muffler. i need to check the setup again.

i was gonna use the pipe from heat exch to turbo. turbo to muffler, muffler. then the inlet to compressor, and outlet from compressor to ic. the ic would probably be discarded (due to fit) and custom pipe to 3.2 inlet.

perhaps i'm way off with compatibility of parts.

the unit still has to be capable of flowing the exhaust - low or high boost. if the turbo is too small on the turbine side it will restrict exhaust flow too much, therefore more back pressure and more heat. not good.

the idea is to use the 5psi to give more airflow to create more power. 5psi is 5psi. matching the turbo size to the engine determines how that power is delivered, and how the car drives.

i figured a 930 unit on a 3.2 would drive similar to a 930 engined car - but with a bit more off boost ooomph. except of course i only wanna use 5psi.

thats my understanding.

bell · bell's Garage

ok i've been thinking of this lately..........
i have an 85' so i'm familiar with the setup you're working with.
find an old cat you can cut.......then make a flange for the turbo to weld to that pipe.
if the heater blower motor next to the intake is removed (options?) you could run your "turbo-ic-engine" pipe through there.
the new air filter could be mounted in the fender (protective shielded course).....
a few oil lines......
then all you have left is the turbo to muffler pipe.....you're not
running a cat so there is alot of room to play with.

i have that TDo4 sitting in my garage.......hmmmmm......just what i need......more power

beepbeep · 05:39 PM

Ok, guys. After many beers (disclaimer)...my advice:

3.2 engine is actually better choice for turbocharging, IF you know what you are doing. It already has same core and rods. It has heads that flow more and EFI too. It's the good stuff. OEM 930 engine sucks pretty badly but is over-engineered.

Unfortunately, most of you don't know how things work. You just want more power...cheap. You want to buy cheap-ass conversion kits from rfng. Things are complicated. You have to read the books and listen to what Juan and other guys have to say. It's not easy. Period. It cost money and/or talent, anyone telling you something else is lying. There are no shortcuts, it's the sad truth.

I might be wrong, but i'm afraid i'm not :-(

bell · bell's Garage

i've been building turbo dodges for years (i know it's a different engine entirely) but have countless hours of research on turbo systems themselves.
turboing a carrera engine is feasable and fairly "simple" if you understand the concept, the adjustment needed for the 3.2 is there if you're only running up to 5lbs.
i'm still researching this though....

and cheap? turbos are expensive

Mike the mechanic · 05-29-2003, 05:58 PM

A tdo4 is way too small for a 3.2 liter engine, let alone a Porsche 3.2, which flows a lot of air in the top end. I have been doing turbo conversion for many years, and for the last couple of years getting into Porsche turbo conversions.
A turbo designed for a small engine with 20 psi is not the same as a turbo designed for a large engine with 5 psi. You will end up over-spinning the turbo and creating crazy surge. You need a compressor that flows a high volume just to keep up to the airflow needs of a 3.2 flat 6, even if you are going to run just 5 psi. By the way, you can run 7 psi safely with no intercooler and 10 psi safely with an effecient intercooler, with stock US compression.
Then you need a high flowing turbine as to not restrict the exhaust flow too much in the top end. You need'nt worry about lag, as the relatively high compression will give you all the low end you need before the turbo kicks in. You want specifics on turbo choice? Just ask.

beepbeep · 05-29-2003, 06:30 PM

Say hello to Garrett GT40:

Ze big momma...

Mike the mechanic · 05-29-2003, 06:41 PM

Now that is an awesome turbo; Garrett's latest technology= super effecient, super flexible and super durable. Is that yours beepbeep?

rick conrath · 05-29-2003, 06:44 PM

In actuality the only real thing that the 3.2 has over the 3.3 is the induction system. The 3.3 heads need to be opened up to flow, but the metal composition of the 3.3 heads is different and more suited to the high heat turbo application. Plenty of people have used the 3.2 heads in the turbo application....but the metal in the heads is different! You are also not taking into account a necessary piston change to a lower compression ratio with the 3.2., that is if you want to make real and reliable horsepower. 5lbs isn't going to build big HP numbers so it questionable whether the bolt on 3.2 option is really worth the expense. Other than that, no real advantage either way. You are looking at a cylinder and piston swap with both motors to take advatage of their full potential.
rick
'78 930