So i was over helping my friend work on his Charger and i was joking around about him putting a turbo on it. He said no he wants an 800 n/a engine, anyway after my comment he walked over to my car and was like hay why don't we take the turbo in your car, find the same one flip it around and put it on there to. Twin turbo mini?!! i laughed then we looked at it it would be more than easy enough to move the stock turbo over a lil split the wast gate line and move the maf pre y pipe. he thinks it would be a great idea. i don't even think that 2 of out cylinders could spool up our stock turbo even tho it only needs to be spooled up to a peak of 10-11 psi. What do you guys think about that crazy idea??? even possible? I think not but want to c what you think.

 

Some one has to know if it will be able to spool up two turbos

 

Well, I'm not a turbo guy, but the engineer/physicist in me thinks that since turbos are designed to work with a certain displacement and RPM range, taking a stock engine and adding a second identical turbocharger without making a lot of other extensive changes is probably not going to give very good results.

(It'll probably be easier than getting 800 naturally-aspirated horsepower in your friend's Charger, though, unless he has a vintage Charger and not a new one).

 

Twin turbos are for people who want strong low-end power but does not have the high HP output as a single turbo would. The Mini's turbo alone has a lot of low-end power so if you were to do a twin turbo, it would serve no purpose IMO. Stick with the stock turbo if you want low-end power and a bigger turbo if you want top-end power.

 

its a 68 r/t charger. so it is better to have one large turbo than two small turbos even tho the lag will be longer for the bigger turbo

 

Thats why in twin turbo kits, small turbos are used. =)

 

And lag isn't as much of a problem now as it used to be, so you can go with one bigger turbo to get massive airflow potential without killing the bottom end. Modern turbos are a far cry from what they were 20+ years ago. I drove a mid-80s Chrysler LeBaron turbo that had horrible lag. When you stomped on the gas pedal, the car would literally pause for a second like it was asking "what, who me?" and then it would take off.

BTW I love the '68 Chargers. I have a '72 right now with the 440 engine, but I still prefer the earlier body styles.

 

There are different types of twin setups. One uses two identical turbos on different banks, and the other uses two different sized turbos to achieve power across the curve.

Also known as Parallel and Sequential setups.

Wikipedia has a good writeup on the both of them. http://en.wikipedia.org/wiki/Twin-turbo

There are a few SRT4's running around with a twin setup.

 

yeah his is a 440 being stroked out to a 505 he is a lil crazy.

anyway so if i want a lot of like 300ish i would not mind a lil more one big turbo is the way to go? i would love to have i twin turbo mini but will it just not work.

 

There is really no point in having a 1.6L twin turbo...the motor is so tiny it would prob do more harm than good.

 

pretty much for a 1.6 just put a big turbo on in

 

Twin turbo's can be used to give you huge top end power as well. You can utilize an undersized turbo for low end grunt, and a behoemoth turbo for the top end. Obviously the large turbo will not spool until the smaller turbo is doing it's thing, but staged twin turbo's are not uncommon.

Here's a pic of a setup.. you can see the left turbo is tiny and the right one is larger. This is why you use a twin turbo setup, you use the smaller turbo to spool up the bigger turbo. (notice dual wastegates to be able to shut down the smaller turbo sooner so it doens't over spool)

 

thx that helps to bad no room to do that under the mini hood and i dont have an extra 5 g's to blow

 

A setup like that will cost you quite a bit more than 5 grand. $5,000 would probably only buy both turbochargers themselves.

 

so is the only way to get 300+ would be a new bigger turbo and a good tune

 

For that much power you would need a new turboback exhaust, polished and ported heads, bigger turbo, and a fantastic tune. And if you are running all that you will want a larger and better intercooler and a CAI to get more air to the engine. Also would probably want upgraded piping to handle the extra heat and pressue, super sticky tires, and a fire extinguisher!

 

Well, maybe not all that, the new turbo might be good enough to get it barely there, but upgraded internals are definitely on the list if you aren't a stock JCW.

Super sticky tires a must... I wish we could run wide tires on these beasts... too much power on these skinny things is just overwhelming.

 

so are the jcw pistons forged and the normal s are alminum? or what is the diffrance between them?

 

Forging is a process used to make very dense and high quality products. A forged aluminum piston is stronger and lighter than a cast aluminum piston. The forged product starts with a solid piece and shapes it under enormous preasure. A cast part may start with molten metal and pour it into a mold. There are variations of the casting process that fall between these two in strength, weight and quality.

 

yeah, but are the jcw forged and the normal s not?

 

No, they are specially reinforced, ground and polished to a close tolerance match. But no where does BMW claim they are forged. Not many autos are manufactured with forged pistons, doesn't work well for the average daily driver. They are great for high boost and extreme power demands but over kill for the average smuck, also due to the cold start behavior, most people would have the car back in the shop the first winter day...

 

what would the forged pistons have to do with the cold start. im prepping my engine for about 300 whp would i need forged and would the jcw be enough? and do you know the stock injector size is

 

Forged pistons typically expand more when heated compared to cast pistons, so they require slightly wider tolerances when the engine is being assembled. As a result, you can get some slapping/knocking noises from forged pistons when the engine is cold - that's what JAceMin was talking about. It's harmless, but it can be disconcerting if you don't know that it's normal.

 

oh k got it so do you think the jcw would be good for 300+ or should i get forged?

 

I would go for the forged pistons. You're talking about getting almost 200 hp/liter out of the engine, so that's going to require some very high cylinder pressures.

Also, the only way you're going to get that much power without stroking the engine (increasing its displacement) is by using lots of boost, so you'll want to lower the static compression ratio down from the stock ratio of 10.5:1, which is fairly high for a turbocharged engine. When you order custom forged pistons, you can specify any static compression ratio you want.