gcs118

You guys said that turbocharged cars don't have headers? What do you mean? Is the turbo the exhaust manifold? Does the downpipe directly connect to the turbo then? Thanks for any info.

Installshield

A Header is generally a tuned exhaust manifold that gives better flow characteristics and keeps the exhaust gases seperate port to port longer for a longer length than a stock exhuast manifold for a natural aspirated engine. I am not sure of the exact definition of a header, however. Turbocharged engines have a special type of exhaust manifold that routes the exhaust gases through the turbocharger's turbine to, in short, force air into the engine. (You are correct about the turbo bolting onto this manifold) I have heard a few guys refer to them as "turbo headers", but they are still very different to a common 4-2-1 header.

Giving the basic bolt-on quick chat thing "I/H/E"(Intake, Header, Exhaust) does not apply to turbocharged cars. The statement that putting headers on a mazdaspeed would make it different story or whatever was said at the beginning of this post was irrelevant for either of the following reasons. 1. The person was confused and thought you could put a regular header on a Mazdaspeed, (Technically you could, but you would no longer have a turbocharged MSP) or 2. The person thought that you could gain power in a MSP by finding a better turbo manifold than the stock Callaway unit, which is irrelevent becuase the boost is set and you would not make anymore power.

Hope that helped....

I forget the URL now, but it was something with spoolin
Here you will find some various Turbo Manifolds

www.AWRracing.com
Here you will find a basic 4-2-1 Header.

gcs118

Yeah it did, thanks for clearing things up.

Installshield

No problem

ZZOOOMM

I boosted my Mazdaspeed to 10 pounds yesterday with no problem. I made a manual boost valve for $6.00 from True Value hardware. The car run great now. No Detination no pinging.

Installshield

It probably will **** up soon...

FM's protege had problems in 5th with the A/C on, although it had an MP3's ECU (and that was at 6psi). Not sure how similar that is to the MSP. Either way I would bet that in certain situations it will ping.

macdaddyslomo

the way that mazda likes to run rich i think he will have no prbs running a little higher boost...we are only talking 3 lbs here over stock and most turbos tend to "spike" 1-2 lbs anyway...keep in mind the Mazdaspeed's ECU is tuned for boost,its not a stck or even an MP3 ecu......

poktrokt

**Now to the boost. It is set at 6psi. You can probably bypass the computer (void warranty but who cares) to get to at least 10psi. You gain approx. 10hp per psi/boost. So that should be another 40hp. So lets say 25hp (from the first mods) + 40hp=65 more hp. This should put you at est.222hp which should increase your 1/4 mile by probably almost a full second.**

redrims, your theories about boosting have decent thought but little merit. you will increase hp by upping the boost. do not expect 10hp per psi. each turbo is different. 1psi may result in only a 5 hp boost with the t25, where a g20 or t4 will have an increase of 15hp with 1psi increase. Its all about airflow. the MS turbo is a small t25 designed for as close to instant response as possible. It will run out of gas early due to the small impeller size. the impeller could be reshaped for more boost but you would still be limited by airflow. t25's only flow about 325 cfm. they are equivalent to the 12a on my conquest. switching to a t3/4 hybrid would be the way to go for real power and street manageability.

As for headers, there is a such thing as a tubular exhaust turbo manifold. there is a company in fl that claims to make one for any car. I would avoid these for the simple fact that the turbo adds a lot of stress to the welds of a tubular manifold and will shorten its life compared to the cast manifold. cast manifolds can be honed and ceramic coated to decrease spool times.

If you are not going to increase the size of the turbo, go with a 2.5 mandrel bent exhaust from the downpipe back. Turbos do not like backpressure. Yes, this will increase horsepower as well as improve spoolup. if you go too big though, there will not be enough pressure to kep the gases flowing fast enough for proper spool up.

Personnally, I don't like the location of the intercooler in the MS. it should be mounted away from the radiator, not against it. Increasing boost without changing that will result in more heat soak and less power as air temps rise. get a good fron mount ic asap.

Thats my piece for the night. blowdryers rock!! Blow hard, go fast!!

Later

redrims

Thanks for the info.

poktrokt

no prob.

chdesign

The MSP is set at .5 bar stock. The ECU is tuned for a turbo so pinging isn't as much of an issue as with the MP3 with the FM kit. As for the intercooler. One could probably use the IC kit from spool-turbo and just modify the piping for it to fit. That big PWR intercooler front mounted does very well. Also there is NO fuel cutout at 10 psi this is a myth a rumor not the truth. We have had one guy on teh other board boost to 13 psi with no problems granted he didn't leave it there but there is not a fuel cutout as once thought. And actually a turbo system likes 0 backpressure for it to perform at is peak. Read Maximum boost and you will read the same thing....i'm no where near an expert on turbos but I will take Corkey Bells word on it and EVERY DSM, SUPRA, and RX-7 guy out there so i'm goign to stick with 0 backpressure on my setup. I have to agree though the T25 in the MSP is smaller than the T25 used in the DSM's so it is itty bitty....a T3/T4 is a bit of a exageration I think though the T3/T4 to me is not a feasable streetable turbo. I think a good larger T3 will do perfectly like a 55 trim or a 60 trim T3 and you will be good to go. The turbo I am currently using is the equivilant to a 58 trim compressor and 38 trim turbine T3 excelent spool time and great effieceincy.

Installshield

I apologize then, I didn't realize the MSP's ECU could handle it. In some other thread, people were saying that is most likely the same ECU as a ES, seeing how it runs so rich stock, but never verified it. I just went with the FM one knocking, thinking the same would happen in a MSP...

saided18

whats about the internals?? hasn't it been know that the stock intrenals on MP3/MSP can only handle up too 223whp? and the tranny isn't that strong either.