In imitation on my post on the technical issues threat where I explained that pretty much my whole engine is toast...
So a rebuild would cost me ~€2400 in parts and labor, not including new rods and a new turbo. But that's only where the story begins.

Since my Coupe stood still I've had fantasies about twincharging a 16vT, much like the Delta S4 back in the 80's (which makes me sound old :))
So on a good day a long time ago I bought an Eaton M65 4th gen. supercharger. The one with the teflon coated runners. Got myself a real heavy tubular exhaust manifold and found a leather interior for a bargain at a car demolition site. Just for the sake of spending on the Coupe

Next are my questions:
Since I need new pistons, rods and a turbo what are the ideas of the pro's on FCCUK? What would be an ideal combination of pistons, rods, turbo and supercharger?
I'm aiming for 375 to 400 horses. But I guess with the right internals I could go a bit higher.

*edit
What kind of management would I need to drive a twincharged Coupe? Can I get the standard chip remapped or do I really need an aftermarket ECU? And if so which one?

Hi, Im not a pro but im pretty sure that standart chipped ecu should work fine. But for turbos there still is some questions. are you going to connect them in paralel ? if so you should get 2 smallerones as flow from both turbos will add up and make a pressure. if you add two big turbos you probably will get late spool or even very late, lets say just before your rev limmiter. theoricly it should be like that but in real life it might be different. maybe someone else know better ;-)

You need a supercharger setup with a bypass valve. Something that will bypass when the turbo starts feeding it pressure over 1 atm.

Std ecu mapped will be fine. The engine build can be done as a normal single turbo engine.

Hi. I also toyed with the idea of compound charging a few year ago, but figured a well tuned turbo-only setup would be much more cost-effective in terms of bang-per-buck, and simpler. No reason you can't do it just for fun though!

375-400 bhp is decent horsepower but it's certainly wouldn't call for any particularly exotic engine parts. Any of the good makes of steel rods and forged pistons would do. I myself stock Wossner pistons and ZRP conrods, so naturally I recommend those

Since you're planning on using a blower for low-to-mid range grunt the benefits of an expensive modern ballbearing, billet turbo would be largely negated. So a good old fashioned T3/T04e 50-trim will do the job nicely and cheaply! I really rate Turbonetics' T3/T04e turbo.

As said above, the stock ECU will be perfectly capable of handling your engine spec, as long as it mapped competently.

Funny! When they rebuild my 16VT engine a few months ago they used exactly those parts you sell. Wossner pistons with ZRP rods. Did you sell some past few months? And I have a Garrett BB T04E too.

Only some new cams and pulley on my wish list. And a remap

Nope, literally only just gone 'live' with my new parts store this week.


I can help you there in both cases PM'd

That advise is pretty much what I had in mind myself. To get a T3/T04e somewhere cheap instead of an expensive Garrett GT turbo. Where could I buy a T3/T04e? I checked eBay but don't know if they are chinese ripoffs or the real deal.

The Wossner pistons were advised to my by the rebuilder too. Anyone got a good adress where I can buy/import a set?
Or are the Gazella Racing pistons a good option? I know the Gazella's have some kind of coating on them which should help lubrication.

Never hear of ZRP to be honest. Where could I buy those? I had a look at Wossner rods which are pretty expensive and Gazella Pro H rods which are about half the price of the Wossners.
All in all I want to get to 375/400ish safely, without worrying about blowing my engine all the time.

Do I really need a bypass valve? I reccon that I could do the same setup as eg. a Delta S4.
Supercharger > chargecooler or SMIC > turbo > FMIC > engine.

I always thought that with the use of a twin screw supercharger I don't need a bypass since the turbo, once spooled, just sucks air through the supercharger. A centrifugal charger or roots do need a bypass since the suction of the turbo could damage the charger.

The S4 had a complicated bypass system that phased out the supercharger as boost rose and also bypassed the charger at idle.

Twin screw and roots chargers are very similar in design. Centrifugal chargers are like belt-driven turbos. The bypass isn't to protect the charger (it won't come to any harm). It's to phase out the charger as the turbo starts doing its stuff. Also if you have a lobe (roots) or twinscrew in front of the throttle body. Then you need to bypass air round the charger at idle because the pressure can apparently bend the throttle butterfly.

The most simple setup is just to have the turbo blowing into the charger and charger blowing into the inlet permanently problem with that is you're also compounding the inefficiencies of each system; 75% efficient for the turbo and then 50% of that 75% from the blower!

I'd say that last statement isn't quite true about inefficiencies. Take a look at this thread and the dyno graph says it all. 2.0 EVO5 and a huge GT42 (I think) turbo on it

That doesn't say anything! "Efficiency" in forced induction refers to the charge temperatures in and out of the turbo or supercharger. A dyno printout tells you nothing about that.

You only find out about effeciency by taking measurements and doing a bit of maths!

I didn't read all 53 pages of the thread, so apologies if I missed this, but I didn't see any mention of efficiency anywhere in there

Some modern superchargers have bypass valves built-in. The by pass just equalizes the pressure on each side of the SC. So when you're cruising along its not dragging on the engine. This is important as you don't want to compound with a SC as KJ pointed out.
You also cannot suck air through a SC. It would cause a vacuum. S4 setup is the best IMO as a sequential setup.

The twin turbo design as posted on this forum has got to be a lot easier and IMO should work a lot better.

This is one of the better twin charged 16VT builds I have seen.

No, it doesn't, but the way you worded it made out that supercharging and turbocharging is a pointless exercise due to it being inefficient by throwing some % numbers about. I was merely highlighting that it isn't pointless as the graph shows.

Scuderia, those pics don't work. We need to be registered to see them, so maybe save them and upload them to photobucket.

Hi Scuderia. Those links to don't seem to work.

Cheers Alexis, all the jobs I was meant to do last night never happaned after you posted a link to a 74 page thread!
He has quite the car there though, fast as. Not a lot of detail (I can understand him keeping it to himself) but it apears that the turbo feeds into the charge cooler which then feeds in the SC and then going through the air/air intercooler before reaching the inlet manifold.
Anyone know what type of SC he's using?

There's nothing wrong with my wording in this case. When talking of turbo/superchargers, efficiency is the engineering term used to describe a compressor's/blower's ability to compress air with respect to how much it increases the charge temperature.

Ec= comp. efficiency
PR= pressure ratio
Tamb= ambient air temp at comp intake
Trise= temperature rise (difference between intake and outlet air temp)

Ec=( (PR^0.283 - 1) * Tamb )/Trise

In a similar vane; when talking of intercoolers, 'efficiency' ratio of inlet temp to outlet temp with regards to ambient air temp.

Note that air flow or horsepower don't come into either of these equations.

When talking of turbos/blowers and ICs, any other use of the word 'efficient' is wrong. It's one of those things that many people misunderstand when talking turbos - just like the term 'compressor stall' - it refers to AIRFLOW stall. It does NOT mean your compressor has stopped spinning!!

I didn't throw around % numbers! Most turbocharger compressors have a maximum efficiency of approx 75%. Roots superchargers have a maximum efficiency of 50%.

if you attach a turbo and blower in series then you multiply the efficiencies: 75% * 50% = 37.5% ie. not efficient!! - And hence, why the car in your post has a cooler after the turbo, then another cooler after the blower, without two coolers all you'd have is an expensive hair drier.

BTW please don't take these replies as being antagonistic, I don't beef with anyone unless they beef with me! I'm just giving you the 411 on turbos

You're welcome Nik I've been following that thread for a while and believe the setup you mention is what he has done. The supercharger type he is using is one the below :

Although I'm sure he mentioned in the thread which one he was using.
I prefer chicken anyway

i doo like some nice lamb...

There is some weird format in these photos. I can't view them after saving them. They need to be viewed on the webpage.

http://www.turbo124.com/forum/viewtopic.php?f=2&t=2374&start=40

About half way down

This SC has a bypass built in. They guy is in the USA and we didnt get to see the final result.

If you're going to run it like that without by-passing the supercharger once the turbo gets going you'll be compounding the boost and getting huge manifold pressure's, alot more boost than you would need to get to 375-400hp

I'm not that familiar with superchargers so not sure how you could by-pass it, maybe find some way of disengaging it as the turbo starts making boost

S4 Setup


'In 1985, Lancia engineers tested a S4 engine under extreme conditions, reaching 5 bars boost, developing around 1000 horsepower'

That quote above is from wikipedia so not sure how accurate it is but if it was boosting at 5 bar I would of though it must have been compounding the boost, as KJ said about inefficiencies if your feeding boost from a turbo (hot compressed air) into a supercharger it will carry on compressing it but will also add more heat to it, I know the S4 was labeled as a sequential setup but I suspect it was compounding the boost to some extent, possibly why they felt the need to intercool each stage

Think the biggest problems you'll have are trying to get everything under the bonnet and getting the boost under control either coming up with something to by-pass the SC or reduce its pressure ratio when your turbo gets going

Twincharging seems more complicated than I may have anticipated. But since I already have the SC I just may give it a try. The whine of a SC with a turbo and the constant blowing off just sounds so mad I need to have it

First thing to do is select which pistons and rods I need and figure out what compression I want to get. 8.0:1 or 8.5:1? I don't really understand why but I think 8.0:1 is what I need to get to.
So who can hand out some advise on where to get pistons and/or rods for a good price.

With a supercharger I'd be inclined to pick a lower Cr piston.

Check your messages!

I tried to find on the thread what boost he is running to get 790.5bhp out of a 2 litre engine at 7205rpm - I could only see 2.6 bar. If that's all the boost he is running, then the power figure is plainly nonsense.

And what is your reasoning for that?

Do the maths...

So I'm getting the Wössner pistons and ZRP rods.

But that to do for a turbo?
I've read tons of forums but I can't really figure out which turbo I need and where to get it. I don't really trust no-name turbo's so I guess it'll be a Garrett or Turbonetics with a journal bearing. (Journal being the tougher option and I don't really care about lag because of the added supercharger.)

What's the difference between a T04b and T04e? All I know the b is 20+ years old design. And what about trim? Since lag is no bother should I get a .60?

I can get a T04B Super H Stage 5 trim for pretty cheap. Would that suit my 'needs' for 400bhp?

Think H trim Stage 5 will be a little over kill for 400 bhp!! Stage 3 turbine is perfect for 400, it would probably do 500bhp to be honest!!

Nick

TO4E 50 trim with stage 3 hotside would be perfect.

You can buy this turbo from Turbonetics or atpturbo.com