so i have read the various advantages and disadvantages of draw through and blow through MAF systems on turbo TC s how ever i am still uncertain which to use.

I have some eBay intercooler piping (Emusa)
http://cgi.ebay.com/ebaymotors/ws/eB...52208928170683
and it does not have a Maf plate in the piping. How ever i have got a cold air intake which i intend to butcher for the MAF plate.

The question is should i blow through or draw through. blow through will be easier beacuse i wont have to fabricate an intake pipe to reach the maf plug.


for now i will be running a low boost set up with 5psi 550cc injector and no piggy back on a stock ecu.

will the blow through MAF work or will i have to run a draw through set up due to stalling issues associated with this set up with a stock Ecu.

so i see my self having three options
1. fabricate an intake pipe for Draw through set up
2. cut the intercooler pipe and make a blow through set up
3. find a MAF extension lead which will allow me to run the maf right next to the turbo with little need for fabrication

What should i do ??

Thanks for any input

 

do a draw through, and recirculate the MAF. your tuner will be a lot more happy. even with a blow thru setup, we had turbulence problems, and the MAF was more than 8 inches away from the bov.

 

and you can run a draw thru without recirculating it. it just gets kind of annoying cause you get more downtime between shifts, and it will backfire stalling can happen too. but its nothing to freak out about.

 

Hey, I live in Brighton. I'd personally go with a blow-through set up. I've used both set ups. You want to have the MAF between the throttle body and blow off valve, as close to the throttle body as possible but about 4" away from bends and somewhere at least 6" from the blow off valve. This is from what I can recall.

What are you planning on using for engine management, and who's going to be tuning?

 

Thanks for the info guys. Does any one know if there is a plug and play MAF extention?

probably going to go for the the AEM FIC with plug and play seems to be the most popular from what I see.

as for tunning in the rochester area i know the STM have a good repuation for tuning and a nice dyno, dont know if they have ever tunned scion before but i would probably start with them when i get the piggy back. they just relocated check out their site.
what about your self done any tunning?
have your self a local tuner you could recomend?

XPRTc is your BOV vent to atmospere or receirculating?

 

there is no MAF extension that i know of. you might just have to extend the wires yourself.

 

I am currently using the TiAL Q bov and blowing off to atmosphere.

I go to STM for my fabrication needs and to use their dyno. They are a very experienced group of guys that do great work and have a handful of very fast cars to showcase that. I know they would give you the best tune to their abilities on the FIC, where their strength lies is with the AEM EMS standalone though.

Dezod Motorsports is in Lancaster (right outside of Buffalo) and Paul has a lot of experience tuning Scions with a variety of engine management systems. Paul has tuned my FIC and currently my APR X1. It's only slightly inconvenient to drive there, it's not that far.

My suggestion would be to call both places and ask every single question you have concerning suggestions, tuning rates, and experience then decide from there. PM me if you ever want to meet up because my girlfriend is currently living in Fairport. Good luck!

 

Thanks for the info XPRTc when i get more money i will go to the next stage of turbo tune and get the AEM FIC and tune it and see what i get. how ever i have just started school and not working as much as before so the money flow has decreased
would be great to meet sent u a personal mesage

 

Fyi u may have some issues runnin 550's on a stock ecu. If ur only running 5 psi i would leave the stock injectors in and dont beat on it til u get an fic amd a tune.

 

Not trying to doubt your knowledge or anything but from what i have read there were a few turbo kits that ran on 550cc without problems.

what kind of issues may i face, trying to get as much knowlege as i can before finishing the project. i am not going to beat on the car but if i have a little heavy foot for a minute i would rather know that i am getting enough fuel rather than running to lean and detonating. could i run a little more boost than just 5psi when i have those injectors and no tune.

Appreciate any input you guys can give

 

Im not sayin that it cant be done. Just from what ive gathered u may experience issues at partial throttle. Most of us boosted guys wont run any larger than 440's without any kind of management. The factory ecu may not be able to compensate for the ideal or desired fuel trims to run more boost. Imho stick w the stock injectors while on the factory ecu. 550's may be too large for the ecu to compensate for without a correct tune. I ran about 5 psi w stock injectors for about 5 mons with no issues. My afr's werent 100% where they shouldve been but they were decent. I wouldnt go anymore than 4-5 psi on stock fuel/ecu. Anymore than that and ur askin for trouble. Again im not sayin that 550's arent gonna work without fuel mangement, but the ecu will only put out what its supposed to. This is why we need fuel management also, to add more fuel correctly wo issues. So in a nutshell adding larger injectors may add more fuel at startup and idle but it may do nothing to add fuel due to fact that the ecu will not add the extra fuel desired to run a higher amount of boost.

 

May be I am not reading this right but if these 550 will add to the top end why do people bother to use 440 w/o fuel mgmt
again not trying to insult your experance

 

The stock inj's are 370cc. 440cc is 20% larger, 550cc is 49% larger. The stock ECU can trim 25% long term and 20% short term. The stock ECU can not only trim 440cc inj's but can do so with perfect idle and no CEL's. Not so with 550cc. With 550cc you'll have constant rich codes, stumbles, hesitation, poor idle, stalling and probably foul your primary O2 sensor and plugs. If you still have any cats in your exhaust system, you'll destroy them too.

550cc is simply beyond the range which the stock ECU can handle.

 

absolutly...with 550cc injectors (no managment) your looking at atleast -40 ltft...that alone will cause drivability issues. trust me iv done it more than once either trying to trouble shoot managment/wiring problems or cause a friend needed my stock injectors and all I had to use were 550's.

 

Roger that guys i will stay with stock 370cc injectors untill i get to mgmt thanks for the input.

 

+1 on the last couple of post. 550cc + stock ecu = running like crap and getting pulled on my a d16 Honda Civic (who then can claim how slow turbo tC's are and how he beat one).

Let's not make my job harder than what it already is people....

 

x2 again! horrible idea. some kits CAME with 440's without management, but 550 is way too much.

 

I've ran both and blow threw is the best thing I could have done my car ran , idle. And everything so much better and with out touching my tune I love it and I have a big turbo so it's much Easyer cause I have no room for a big intake

 

Metering air is metering air. Doesn't matter either way entirely. The tunes themselves will be different for sure, however both can and will work just fine. My opinion is "if it ain't broke, don't fix it."

 

FWIW, Toan at P-Tuning told me the same thing Paul just said. He said the only reason they went blow-thru on their setup was so that they could use a larger intake pipe than 2.5".

There is one advantage to blow-thru though. More accurate IAT measurement.