SC + twinturbo

[tha_SwEdE]

Hi!

I got a 2,8L soon to be 3,1L with a eaton m90...
and I'm thinking of putting twinturbos on there to...
Because I got the SC there I dont need 2 small turbos.. but I wanted to know how big with the turbos can I go??

Whats the recomenden boost on a m90 and what rpm do u think that is achived?

Regards
//Tha Swede

[Guest]

OMG you should so do it!!!!

[fivepointhustla]

Can you give details on how you plan on mounting the m90 to the 3.1?

[timg]

Two decent sized turbos will be quite a bit more difficult to install than a large single turbo. I would suggest at least a GT40R or T67 if you will be running a M90 as well.

Tim

[97cutlas$upreme]

ive been told s/c ing and turboing at the same time is a waste of time and money reason being that one will over the power and would be there just to look pretty... but thats just what i heard could be wrong

[fivepointhustla]

It can be a good combo depending on how it is used...like a sc for down low boost with less heat and a huge turbo for top end with less heat OR you could compound charge. feed 1 power adder with the other. Generally triples PSI, but in a boost situation flow is what counts not PSI...as much.

[bjornmk1]

well to hop in on this one:

vw makes a 1.4Liter engine with this concept (in europe)that puts out 170hp at the crank !!!!

and economy is higher than only turbo or sc !

only bottleneck in these setups is the transition from sc boost to turbo boost.
often these systems need to be electronicaly tuned to get a smooth transition.

btw.some guy near me is getting 230hp at the crank out of a 1.3L engine
that is sc-ed and turboed !

[tha_SwEdE]

I've been away.. thats why I havent answerd...

How I plan mounting the m90 depends on if I use a parallel ora a series load... witch I'vnt diceded...


Yeah its eseyer with one turbo.. but I want 2 =P

That about "heard that its a weast of time"...it could be true.. but I dont belive it... I think u could get a better engine with this set up...
But I think its true its easy to go wrong so the effekt will be as u said "one will over the power and would be there just to look pretty"

If u want to compare turbo vs turbo an sc.. look at the Lancia Delta HF integrale and the Lancia Delta S4... thats a good exemple I think...

Regards
Bjorkman (sry for my bad spelling)

[RebelGT]

yeah, it really doesn't pay unless you're running really high boost pressures, and that was before turbo's made large technological leaps. Really not needed anymore.

[sharkey]

there was a guy in the j-body comunity with a 2.4l sunfire with the gm supercharger kit and turbo-ed. it was a holy debated topic, but he did come out with dyno sheets just under 400hp. now it sounds impressive, but there have been people do that with just a turbo. it ends up being a lot more efficient with the turbo alone because the supercharger takes 35hp to drive. yes it did have more low end torque being it had boost just off idle, however turbo lag in a fwd can be your best friend as traction will become an issue

[RebelGT]

yeah, they sold turbo kits for the super charged mini cooper s models, the only reason the manufacturer didn't delete the turbo if I remember right was because the supercharger was integral to the intake manifold.

[X11_STE]

OK, my 2 pennies. I read a very informative article awhile back that had me drooling. I think it was Super Street or something. Anyways, they took a '96 Toyo MR2 V6 CFI (Compound Forced Induction). According to them, the car was scarey fast and impossible to keep straight after all was said and done. The way they explained it, the S/C was excellent for the punch off the line but petered off in the mid range so they put a big turbo on, which had massive turbo lag. When the S/C was topping out the turbo was coming on so the transition was smooth and they even found out that the turbo was OVERRUNNING the S/C and putting power back that was originally driving the s/c!!! So CFI can be a very good thing if done properly. I say go for it and have fun!!!

[tha_SwEdE]

Yeah shore u can get the sam HP with just a turbo...
(One car here in sweden had a 2L 4cyl engine with one turbo, they got alot!! of HP but the car was almost undriveble, so u can get alot of HP on the papers.. but how good does the car realy go)
...but as u said the engine will have more low end... and thats what I want...
And I got a RWD btw...

And if u compare how many people have turbocharged there cars and optimist them... with how many that have done somthing like I want to do...
U'll see thats akmost impossible to compare...
What if people started to do projekt like this and optimised those engines...
I think that will get better engine over the hole thing... than just the end of line rpm... and shure.. u can go with biturbo and stuff like that... but thats not what I want to do...



The Lancia Delta S4:

"The Lancia Delta S4 is a Group B rally car that competed in the World Rally Championship in 1985 and 1986, until Group B cars were banned from competition by the FIA. The car replaced the Lancia 037 Monte Carlo. The S4 took full advantage of the loose Group B regulations and was highly advanced. It featured a mid-mounted engine and all wheel drive for superior traction and handling. The car's 1759 cc four cylinder engine combined supercharging and turbocharging to reduce turbo lag at low RPM. Officially the car produced 550 horsepower (410 kW). Unofficial figures claimed the S4 could accelerate from 0 to 100 km/h on gravel in just 2.5 seconds"

[tha_SwEdE]

OK, my 2 pennies. I read a very informative article awhile back that had me drooling. I think it was Super Street or something. Anyways, they took a '96 Toyo MR2 V6 CFI (Compound Forced Induction). According to them, the car was scarey fast and impossible to keep straight after all was said and done. The way they explained it, the S/C was excellent for the punch off the line but petered off in the mid range so they put a big turbo on, which had massive turbo lag. When the S/C was topping out the turbo was coming on so the transition was smooth and they even found out that the turbo was OVERRUNNING the S/C and putting power back that was originally driving the s/c!!! So CFI can be a very good thing if done properly. I say go for it and have fun!!!

I missed to read page 2 in my latest post...=P

THat sound like somtihng I lokking to do... =P
Do you know what sc and turbo they used?? and how big was the engine? 3L??

A bit of the hole idea why I'm doin this is because its almost never seen so nobody that havent done it can really say it wont work good...
Its harder but I like a challange =)

Thx for all the replys.. =) but can we get back to the subject... =P
how big turbos do u think I can use that will get a nice smooth transition??

[timg]

Sport Compact Car did that with the MR2. I probably have the article at home.

The point is that the roots type SC will increase your low end torque and a HUGE turbocharger that is VERY efficient can be used at the top end for LOTS of power.