S-trim or Single turbo?? and questions that need to be answered

[Black1987Stang]

So I have someone that will trade a complete pdp single turbo setup with very low miles for my S-trim setup. What would you do? I would think supercharger would be better more for a daily driver and since I hear so much about how hard it is to tune a turbo stang and how picky they are with different weather and such. Is there such a thing as turboed fox for a reliable daily driver even on low boost? (5-7psi or whatnot). What's the pros and cons of both? Should I be so worried about the tune as I am?

And could someone tell me how a turbo car is tuned without an fmu? Since a blower gains boost per rpm so it can have the same "fuel curve" every time. But a turbo can say start to build boost around 4,000rpm on level ground giving 1/4 throttle or start to build boost at 2,000rpm at 1/4 throttle towing a trailer since a load is being put on (all just an example). How does the computer know when it's building boost so it can richen it up and increase or decrease the timing curve properly?? I understand you can tune it for WOT since it will have max boost at a certain rpm anyway and stay like that but what about under WOT. I would think some kind of boost controlled fuel enricher (yes yes I know that's a fmu but everyone talks bad about them) would be the best bet but I haven't seen anyone really using a system with a map sensor or whatnot to do that. Any info or enlightenment on this would be great, Thanks! Sean

 

[Foxfan88]

i'd keep the S trim

turbos are nice but if going low boost under 10psi keep the s trim.

the s trim will be ALOT easier to put on, easier to tune on, less parts. less weight
the turbo will create alot of heat and as you said its harder to tune. i'd go s trim for a simple street car.

theres probably a reason the guy wants to trade his turbo for your blower lol he knows it will be easier

as for the turbo tuning i am guessing the EEC would sense an increase in airflow in the MAF transfer and add fuel accordingly but i am no tweecer expert i dont have one yet lol.

i wouldnt mess with an FMU, i am using one now since i have no means of tuning just yet, it works good and keeps fuel in the engine but it runs on the rich side. so much that i noticed a MPH increase at the track by taking 5 psi FP out of the regulator. this could be due to the FMU or a factory ignition reaching its limits, i duno if i am to that point yet or not.

seeing how you have a tweecer you can totally ditch the FMU, i'd upgrade your 24s to at least 42s an tune it through the tweecer.

either way you go you will be happy, boost is very nice.

another thing. some more pros and cons,

the biggest thing a turbo has over a centrifugal is that as soon as it builds boost its FULL boost and goes all the way until you shift

the only "downside" if you want to call it that for the centrifugal is you have to TURN the engine to get it to make boost. the gains are really noticable at HIGH rpm. the engine will act totally N/A unless your foot is on the floor and over 3k rpm

 

[LS-what?]

well I got the PDP 351w stage 2 kit single turbo. For me I chose turbo because I didnt want to deal with belt slipage and all that stress on the crank. Also got a smoken deal on a turbo and its a racecar. The hardest thing is probably trying to tune a blow thru setup.

 

[millhouse]

I really think people over emphasize tuning a turbo setup and underhood temps as a negative.

In all reality, it's going to cost the same to tune the supercharger setup as it is the turbo…and with any competent tuner each one is going to be equal in quality.

As far as underhood heat goes, sure it get's a bit toasty under there….but so what? As long as everything is installed properly the underhood heat is a non issue.

IMHO, the only thing a supercharger setup has over a turbo is the ease of installation. Really though, for many of us, that too is a non issue.


To answer some of the origianl questions, weather affects the tune of any vehicle regardless of n/a or f/i. If you have a good tune, both a turbo and super setup alike will be just fine daily driving in all weather conditions.

As far as tuning without an FMU goes, it's all done with the computer. You tune around the MAF sensor which puts off a voltage based off of the incoming air. Really, it's air density that the MAF is reading which changes with temperature, humidity, barometric pressure, boost levels etc. It takes that along with all other engine parameters and computes the proper settings for fuel, timing etc.

Now if your willing to go with an aftermarket computer setup, there are plenty available that use MAP setups at your disposal. Here is a list of many of the common ones here… http://www.turbomustangs.com/ECUarticle.php

 

[Trbofox]

I have had my turbo setup for 5 years now, have put 30K miles on the setup.The car is very reliable and I am running on an A9l computer no chip, yeh I would probably have an even larger rwhp # with a chip or stand alone set up, but 511RWHP and 622RW ft.lbs.torque@10 psi are a happy enough feeling for street driving and the car runs great. Ialso have a supercharged vehicle and if I were to do another car I would definitely go turbo no question.

 

[ninety15.0]

You will be much happier with a turbo setup. I have been experiencing the same inner conflict as to which one i am going to run on my motor. I think that turbo's are much more street friendly than a blower. Like foxfan said...it will be totally N/A unless you are WOT above 3k rpm. Really whats the point of having a supercharger on a street car then. You just cant be driving around the streets like this all the time. its loud, attention grabbing, and abusive on the car. I think that low rpm boost is awesome for the street...and you will get that with a properly sized turbo setup. I would expect to see full boost by 3k on a turbo setup...instead of 1-2psi with a centri blower setup. Sounds better to me!

And i think Turbo's are actually easier to tune than superchargers. It all comes down to your MAF voltage....thats about it. With a wideband and a tuner...you can make a turbo car extremely street friendly. I would most definitely take that trade!

Oh yea...turbos sound sick!

 

[Black1987Stang]

http://www.turbomustangs.com/ECUarticle.php[/url]

I have a Tweecer R/t, can a map sensor be setup to help tune it? I've only heard of map sensors being used on really radical combos or a total standalone setup.

I got 2 tune quotes so far and they are for $650-900 depending on how long it takes and how my combo is setup as the one had said (I guess he means like draw-thru or blow-thru?). The one includes a second tune for economy, higher boost etc. controlled by a toggle switch.

How many of you guys drive your turbo car daily? Obviously it all depends on the tuner but just curious to see who has a turboed d/d and how reliable they can be.

and Thanks for all the suggestions and comments, KEEP 'EM COMIN!

 

[millhouse]

I have a Tweecer R/t, can a map sensor be setup to help tune it? I've only heard of map sensors being used on really radical combos or a total standalone setup.

I got 2 tune quotes so far and they are for $650-900 depending on how long it takes and how my combo is setup as the one had said (I guess he means like draw-thru or blow-thru?). The one includes a second tune for economy, higher boost etc. controlled by a toggle switch.

How many of you guys drive your turbo car daily? Obviously it all depends on the tuner but just curious to see who has a turboed d/d and how reliable they can be.

and Thanks for all the suggestions and comments, KEEP 'EM COMIN!

I believe the Tweecer only uses the MAF sensor and not MAP. Really though, you wont need one (map setup)…and for the power levels your looking into it would be ideal for you to pick up a lightning MAF sensor and utilize it as a blowthrough.

I myself use a megasquirt and tune using a MAP sensor. Really, it makes tuning a breeze and allows me to "tune as I drive" so to speak. It also makes multiple tunes really un-necessary as your always running the proper tune regardless of boost levels. It's not absolutely necessary however, and I would think either the Tweecer or a custom chip would be all you need.

As far as costs go….I would not pay over $650 including a chip for a tune ($900 is absolutely ridiculous…and shows they have no idea what it's really going to take to tune it).