Guys,

I've searched and read most every thread on "single turbo reliaility," but I still have some questions.

I'm nearing an engine rebuild (coolant seals starting to go) and I'm weighing whether to switch from stock twins to a GT35R. Please give me some feedback on how many miles you've successfully run with your single setup. I'm planning for a very conservative tune in the 12 to 14 psi range. Hoping to get a reliable 360 rwhp out of the car (currently at 320). I know that everyone says that single setups run cooler and extend the life of the engine by removing the hot brick iron oven (stock manifold) from the side of the engine, but has anyone gathered data to support the improvement, or is it just "gut" intuition. Obviously, the stock twins are much more "stressed" and past their peak efficiency range at 14 psi, but the stock setup can also go 70K miles. Is the price of converting over worth the 40 HP gain? So, who's the current high mileage single turbo leader?

Thanks in advance for sharing your insight.

 

I wrote out a big article saying a bunch of stuff that you already know Tim, and went back and deleted it for this.
Stop pussying around and just do it.
The stock twins/precat creat a huge amount of heat. Probably why t2s go 120-130k miles and FDs only do 80k (although fd also has + 50hp and 3-4psi).
You won't be happy w/ anything less than the 320rwhp+/- that you have now.
The GT35R is a KICK *** turbo for 2 rotors. Seems to be the perfect compressor wheel/turbo for 2 rotors, which means good Air temps.

A single turbo will do nothing but help w/ reliability as long as everything is stable and happy.
I don't see that 40+ hp as a huge factor considering you're already at upper 300s flywheel hp as it is vs the 255 stock.

Great efficiency for good air temps, Engine bay will be tons cooler. I would think oil temp may even be a little cooler as it has a more direct route and only one turbo to cool instead of 2 very cramped ones (still just theory. Less stress all around.


You won't be happy w/ any less hp, and as long as you're comfortable in the fact that you're changing the emissions/fuel system this far from stock to accomadate then why the heck not!
I know that you're a diehard rotorhead like I am so I feel safe in saying "What else are you gonna do" without worrying that another LS1 may find its way into a clean FD.


Just do it.

 

Thanks Ben. Wow.... 64 views and counting and only 1 reply. I'm feeling a little "newb" ish with the question. I had hoped that some of the higher-mileage guys would have chimed in and bragged about the mileage and happiness with their setups.

Like I said originally, I'm not out to make 400+ whp, but it would be nice if the turbo system were a little less stressed. As I get older (currently 47) and find that my reaction time is not quite as keen as it used to be, more power (in excess of 400) could add up to more trouble for myself

I guess that's why I'm weighing the switch. That, and mabe not wanting to stray too far from the car's original design intent.

 

I'll get my buddy chris carlisi to chime in, he put quite a few miles on his single setup, something like 15k or so.

 

I've had a single setup for just over two years now...
I have about 10 miles on it.

At this rate I'll have decades worth of reliability on my setup
But seriously, I'm curious to know too.

 

a lot of it has to do w/ tuning, i had 7000 miles before i just changed my set up, motor was good when i pulled it apart over 400 whp

 

Exhaust restriction creates heat; simple physics.
One of the guys working for me has over 20k on his DD single turbo.
We've done a few single turbo piston powered vehicles; 20+ years still running...

 

About 7500 miles on my single setup DD so far.

 

15k on a single around 400rwhp +/- ...... really?.... ****.... i was looking at GT35R for street and i was looking for it to go atleast 50k

moderate HP though... it is going to be a daily driver....... 370-400rwhp max 13-15psi


everyone chime in please :]

 

Thanks everyone for your replies so far. So, 15K is the best we can come up with? I'm thinking that once people go single, they just get power hungry and can't stop themselves from notching things UP, and eventually getting bit.

Not sure if the quote on the bottom of turBRO240's post is a joke or a jab at my post. I know this topic has been mentioned in the past, but I couldn't seem to locate any official "single turbo high mileage" thread.

I know that guys like Chuck Westbrook have been running their single setups for quite some time and probably have logged quite a few miles.

Anyone else? Buehler.... Buehler??

 

We have had a few customer cars in the 20 to 25k range they no longer own their FD's so I have no idea where they are at now. The issue with finding high mileage single turbos is most people sell the car or wreck before they get the mileage on it. I would say there is no reason you can't get good mileage out of one. The thing is to go over the whole car and do proper maintenance. Most of the cars out there are cobbled together and rarely tuned fully. The owner then has issues or blows it up then passes it on to the next guy.

-S-

 

^^agreed. The single turbo setup is a fairly new phenomenon looking at the lifespan of the FD as a whole, and many guys who have the money for a single turbo FD also have a daily driver, thus don't put a lot of miles on them.

In that case my setup should last for a long time

 

What broke the motor GoodfellasFD3s is referring to would have killed it at mile #1 with the stock twins. I would treat it as evidence that the motor will last at least 15,000 not 'only' 15,000.

 

I guess everyone missed this post?




The single conversion should last longer and be more reliable than the stock setup. However, based on what I have read on this forum I think alot of single setups don't last for a couple reason. First, the most typical reason is probably due to too much fiddling with the boost controller or even just plain faulty boost controllers, lately I've read a few reports of some Profec B Spec II's spiking for no apparent reason, even seen the dyno graph from one when it spiked. Another is probably the folks that think that they can throw in some c16 and simply just turn the boost up a few psi without an issue or any extra tuning. And finally, some people get tuned then they do another mod or two such as an exhaust change and they don't get it retuned and then KABOOM!

The key is in the tuning, I think. Get the single setup, do all the mods you want, get it tuned, then LEAVE IT ALONE!(yeah I know how hard it is to leave these cars alone)

 

RCCAZ1..... lol... thats my sig... it was not towards you

 

I put a brutal 13k miles on a motor I built...1st try at that.

The failure was a throw out bearing, nothing turbo related. No reason the motor/turbo wouldn't have lasted much much longer.

 

Thanks turBRO. Funny stuff, and no offense taken. Thanks for clarifying.

Everyone else...thanks for your inputs so far. I've been pretty **** about modifying the car carefully to include having Steve Kan help me with tuning and staying on top of maintenance, so in that aspect, I think I stay on top of things as well as most FD fanatics.

Good observations about cars changing hands and people moving on. That combined with many singles not being daily drivers will lead to sparse data of the kind that I'm looking for (at best). You can only do your best individually and hope that some technical snafu such as a malfunctioning WG or boost controller doesn't ruin your day.

 

I think this is dead on ^

I have ~12,000 miles on the same setup I built back in '03. I drive it when it's 10deg F and I drive it when it's 90 deg F. It stays in the garage when the white stuff is on the ground though

 

My single is daily driven but it's only been running for a few months so far. It was going to be weekend only but my lifted 4x4 gets 10mpg and my FD gets 17.5mpg/avg. My CRX used to get 40mpg but I gave that to my nephew. I don't even remember what the twins felt like, except for the transition kick. You also have to take into acount that people in cold states don't winter drive thier car and it's not cheap converting to single. I am curious as well, so another bumpidy bump.

 

i had about 10k miles on mines, t78 at 10psi 320ish. reason it went was due to poor maintenance(read below) on my part and that i would mess around the engine way too much. im guessing the time that my lower rad hose broke and it over heated and the time that the turbo return line broke and i drove it for like 20 miles(beating on it on the highway), might have something to do wit it going...next up 15 - 20 psi daily, an this time i wont mess with it...

 

Oh yeah, I forgot to mention another big reason why some single turbos don't last. People buy that chinese ebay turbo kit bullshit that is either no good from the get go or the compressor blades shatter after a few miles sending pieces of shrapnel into the intercooler and if your really unlucky into the engine.

I'll never buy a turbo kit off ebay... At least not one that says "Turbocharger" on the tag...

 

Now that you mention it, your inner coolant o-rings definitley looked a bit brittle when I pulled your motor apart. I didn't see any evidence of oil starvation, aside from your front stationary gear bearing being pretty worn.

 

about 40K on 350rwhp and 30K on 400rwhp so far

 

If you want high mileage out of a single turbo I have two words for you, WATER INJECTION.

 

Werd.