Since needwings is making headway with headers I was wondering, is it worth it to get aftermarket headers with a rear mount turbo? I've done research and I've gotten different answers. Does someone here have a really good understanding of thermodynamics?

 

I don't know about thermodynamics but think headers and a turbo would be getting up there in cost. You can get more power with a turbo by adding boost instead of headers. Inter-cooler with take care of the thermodynamics.

 

Few questions about gauges:
On the air fuel I see some people welding a "bung". Would it not be easier to tap into the existing wires from the oxygen sensor? What are the pros and cons of this?
Where a bouts would you put the boost sensor? on the intake manifold or on the intake before the throttle body? Any ideas on this would be appreciated.
Any Brand name gauges to recommend? I like the Dyno tune gauge that Mrmiata suggested it was small and looked like a good fit.
To all of you that made my Christmas list ..Have a good Christmas and for those that didn't make the cut...Merry Christmas to you too.

 

Back at ya on the "Merry Christmas".. and a happy new Turbo Year ... one way or the other! LOL.

 

Regarding headers, if running low boost 6-8 psi, standard manifolds should be fine. Running higher boost you need to eliminate exhaust restriction as the turbo itself will start creating high rpm restriction and impact boost pressure as the engine has to overcome the pressure build up in the exhaust. Sizing a turbo is usually walking a line for best fit.

You will need a bung in the exhaust to mount the wide band AFR sensor which is completely different than factory narrow band sensors. Your boost sensor should be plumbed in the manifold after the throttle body. NEVER tie into the brake booster vacuum line. Also, use a vacuum manifold block to supply the vacuum reference for gauges, any electronics, BOV, etc.

 

Thanks this is what I was wondering. I know headers free up flow but I was reading that rear mounted turbos need the back pressure. So obviously there is a point where headers may or may not be required, I just didn't know when. Thanks MrMoPar!

 

A turbo needs exhaust flow, not backpressure. A turbo always acts as a restriction in the exhaust flow. It becomes critical with increased boost pressure. For example, (numbers for example only), if turbo is pushing 20 psi into the intake, and you have built up 10 psi back pressure in the exhaust, that pressure effects the flow into the cylinder as the incoming pressure must push against the outgoing pressure to overcome it, so the waste gasses are slower leaving the cylinder, so you don't get as complete of an intake charge into the cylinder so your available oxygen to support combustion goes down. You leave potential horsepower on the table. The higher the rpm, the less time to fill the cylinder with a fresh charge. Cam profiles also have a big impact as well.

 

Thanks for clarifying sir. Really appreciate it.

 

Every turbo is a compromise. One that performs really well on the bottom end will fall on its face on the top end. One that makes big numbers on the top end will suffer off the line. An engine speciffically designed from the start for a turbo will have a wider power envelope over an NA engine converted to a turbo. Oddly enough, it is hard to beat a stock NA cam profile with a low to mid boost turbo. The worst thing you can do is to install a blower cam in a car with a turbo. They just don't work the same. I have seen a car making good power fall on its face after installing a blower cam. The problem is overlap. Too much and the turbo boost will fall off as it is blowing the charge straight through the cylinder just as if you opened up a vent to atmosphere. For street use, I like a turbo sized to make big torque numbers early and then drop off in upper rpms. How often can you wind it out in normal driving? My 300C running 7 psi (5.7 HEMI), went from about 220 ft lbs of torque at 3200 rpm to over 500 ft lbs of torque and picked up about 120 Hp peaking at 411 up at 5200 rpms. This took a stock 4200 lb sedan from about 6.25 seconds 0-60 to 4.18 seconds 0-60, and from 94 mph in quarter to 110 in the quarter.

 

how do your tires last on the 300c ? my moms has the same engine and is tearing up tires with a stock setup! imnot even gassing it all that much, and esp off? forget about it!

 

So I thought I owed you a update on what's happening. My fabricator took a lot of measurements and templates a month or so back. Within the next 3 to 4 weeks the stainless steel will go to the water-blaster to get cut out. He is going to fabricate some parts ahead of time so my car won't have to be down as long.
However my brain has gone into limp mode trying to make a decision. Like piping size, to use my inter-cooler or not , with 4# to 5# of boost, is it necessary?, injectors..do I need my larger ones? I see Kleeman used the stock ones. All the research I have done says larger.
Now when it comes down to gauges, too big,too small,what will they look like, where will I put them, too expensive, too cheap too much for shipping on and on and on.
After all is said and done I'll write a book on it too, everyone else does. On how to turbo or how not to turbo.
Right in the middle of this I wonder why there is no Goalie in Curling. Got to get my brain out of limp mode.

 

3" exhasut all around and dump the cats if you can. if not run 100 cel cats. air to air i/c the cooler the intake air the more power you will see.

gauges. arf, boost , egt are mandatory. k4 knock sensor highly recommended how you package them are up to you

 

now this is how to build a proper turbo crossfire!!!!

https://sphotos-b.xx.fbcdn.net/hphot...26504153_n.jpg

 

I may be wrong.. but that has tones of SRT roots doesn't it?

 

absolutely. the main difference being the amount of boost each can run. still a v6 based crossfire. that motor is as far from a s/c v6 as can be now. complete rebuild and upgrade. done the proper way

 

I think if we the "NA" crowd just had a plug and play see the boost afr map adjuster.. we'd already be there.. LOL. Thats where the SRT has the advantage of switching out to turbo.. or turbos..

And to be honest I think that is really what kills me at this point about "those other guys".. a year to put hardware in place.. really now..and after my "response" email.. you can bet they will get another inquiry from me on that "only two weeks left" notice..

 

Wow that's one krazy turbo build ! Did your friend Tony tune it ?

Roadsterguy, that was a close game, lots of my friends are Seahawk fans, coming from the Pacific Northwest, I'll be taking them Kleenex tomorrow, hell of a Season.

 

That is som planning and it looks very nice! I would love to see how they ran the exhuast. I would run a cowl hood to vent the turbo.

 

no tony didnt tune it. thats importlabs car he is on the forum

 

So I bought a gauge, should receive it in a week or 2. Just wondering where would be a good place to run the wires from the engine compartment into the cab..any suggestions.
This is where I got the gauge..one square gauge the will show boost and air fuel. It is a small one so I should be able to fit it somewhere.
Search Results - Square digital gauges, tiny compact size, sticks anywhere, dual gauges

Thanks to mrmiata for showing me the site. I appreciate the help I'm getting from you guys.