boost on stock engine.

Bose

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2004 SS RX8, Sport, 6sp. some mods.
I am looking at adding some boost. e.g. a turbo kit. Anyhow I'm wondering if anyone knows what kind of boost can the stock engine take, I've heard about 7-8 psi, is this right? Also wonder what kind of things should I be concerned with in the way of bearings, pulleys, location of intercooler, any weak spots basically that I should beef up before I boost?

Any help will be greatly appreciated.
 
oh and you dont really NEED an intercooler with 7psi but it is reccomended and if you are only pushing 7 dont worry about anything you should be fine
stock
 
If you are only going to put 7 psi then what is the point. Upgrade the motor first and then turbo it, put down some real numbers.
 
7psi will double stock numbers, or come close to it, correct? I'm also contemplating down the road to boost. I don't really want to build the motor, as I plan on keeping boost at 7 or below. I just want a little more OOMPH outa the car. Won't be street racing, just want to know I have the ability to pass someone. Right now, that's not an option


Tylor
 
you should have no problem running 8psi. I have been doing it for 4 years now with no problems and I am fairly hard on the car. occassionaly I run 10psi but only for real short periods of time.
 
7 to 8 psi can net you an added 70 to 100 wheel horsepower depending on the setup
 
you also have to think about what size turbo you want to boost. 7psi on a T3 is very different than on a T25.

I ran 12lbs all day long for four years on my T25 - "stock" MSP block. lol, it did blow up a few weeks ago, though :)

I agree with Jake_isr, though. Put the goodies inside the engine first. You've already been bitten by the zoom bug. Trust me when I say that 7psi (even on a T25) will not fill the urge for more "oomph"
 
Quote-icespeed-You've already been bitten by the zoom bug. Trust me when I say that 7psi (even on a T25) will not fill the urge for more "oomph"






60-70 HP won't help my oomph problem? (dunno)

Hmm. I'm not looking to build a racecar. I know I won't ever be able to take an STI or Evo off the line with stock internals. I don't want to try. I just want some much needed power.

Now, if after I install the kit, and, I want more power, I might build the internals, but, I'll have a hard time justifying that after dropping $4000 on the turbo kit. Wife's already buggin that I'm talking about dropping that kinda money into the car a month after buying it.

Tylor
 
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60-70 HP won't help my oomph problem? (dunno)

Hmm. I'm not looking to build a racecar. I know I won't ever be able to take an STI or Evo off the line with stock internals. I don't want to try. I just want some much needed power.

Now, if after I install the kit, and, I want more power, I might build the internals, but, I'll have a hard time justifying that after dropping $4000 on the turbo kit. Wife's already buggin that I'm talking about dropping that kinda money into the car a month after buying it.

Tylor
really? (uhm) that's a pretty nice bump on our cars?
 
was in reply to icespeed's comment about it not being enough

Tylor
 
it doesn't have to do with building a race car, I don't think mine was. The problem is the whole "grass is greener" thing. Don't get me wrong, 60-70hp is alot for a protege and you'll love it... at first. When I bought my MSP, I didn't even know it had a turbo. I owned a '99 LX and was comfortable with the protege interior. I saw the MSP and it came with nice rims, a spoiler, ground effects, etc. And when test driving it, I heard the loud whine and I was thrown to the back of my seat. It was awesome. I had a grin from ear to ear.

But small things started to annoy me. I liked that it had the "oomph", don't get me wrong, but in times where you really need to get away, 170hp is lacking. For example, I do alot of highway driving (most roads here are 45+ and then 70 on the "highways"). 7 psi is not enough to get you on an on ramp ahead of the cars that are already cruising. You can't blow by a soccer mom in an accord at a light if you have to get over (if the lane ends). You'll just have to wait for her to pass and then take out your blinker and get in line. Yeah your car will be faster, and you'll feel it, but you're only shaving a few seconds of 0-100mph, not 0-60mph. In real world applications 7psi (on a T25) will only allow you to put up a fight against stock accords, 6s's and IS300's. Don't know about up by you, but those are pretty much the only "cars" that people drive down here. Well, that and CX-7's that's invading the market. You have the same problem though, 200-250hp "heavy" cars will stay within your blind spots in a lane takeover, thus negating the need to invest in the turbo to begin with.

People have repeated for four years now that 8psi should be the top of your range on stock internals/stock ecu. I'm sorry but that 1psi doesn't make that much of a difference in a real world scenario. Not to mention, I remember plenty of people blowing their stock MSP motors, at stock boost (6-7psi). If you build the engine first, you know for a fact that when you are ready, your car will be there waiting.

I drove for four years, 90k miles at 12lbs on my stock block. Every time I stepped on the gas, in the back of my mind I was waiting for the tink... tink... boom. It was pretty stressful knowing that it could blow at any time, but I'm insane, I liked the risk :). It did blow a few weeks ago. I'm not upset, I knew not to run that much unmodded. But... no soccer mom ever succeeded in disallowing me trying to merge. It has nothing to do with making a race car, it has to do with being able to step on it if you "really" have to.

P.S. sorry about the long post, just wanted to get my points across :)
 
Point made, but, in all reality, it's still a Protege. If I wanted something fast stock and reliable, I'da just gone and got something with a V8. But, I wanted good gas mileage and the ability to haul stuff. The car's a blast to drive, but, it just needs that little push in the motor department.

When it comes to merging, I never have tried to "Blast" infront of anyone. It only pisses people off and they wind up tailgating you anyways. I don't mind waiting my turn to get onto the highway. Also, I know my roads, so, I'm not going to be "Blasting" infront of someone to get 3 lanes over to turn. That pisses me off when people do it to me.

My car's pretty recognizable, only one other Laser Blue Protege 5 around that I've seen. And, by driving nicely, it rubs off. I let people in, I see the same people afew days later, they let me in. It works well.

I just want a little more power, and, keeping it reliable. So, I think booting on a stock motor with 6-7, 8 max PSI on a stock motor is for me.

Tylor
 
Just be sure to do it right! BY the way that $4000 is only the start just like it was mine! Here I am with my motor being built and mods up to $23k. Clutch Exhaust Motor Mount Bushings Suspension Welded LSD Gauges
these are all going to be necessities soon for you also!!! I started at 8psi then 10,11,12 okay onemore bump to 13psi with a J&S knock sensor to keep it in check and soon 18-20psi on the Speedcircuit motor!!
 
I run 10psi on a T3/T4 (MAM Thumper Kit) w/ stock block, and haven't had a problem in over a year. Keep in mind I have supporting mods, and my tune is for 11-12 afrs across the entire rpm range.

I do have a spare block sitting in my garage though, just in case lol ;)
 
very well. :)

Other things to consider:

-your gas mileage will go down with the turbo.
-iirc, the exhaust cam on an MSP was different b/c of the turbo application
-the stock block still has a chance to blow, but hey all engines do - may want to "overhaul" your engine.
-don't go with the callaway exhaust mani, they crack frequently.
-as far as i know, the cranks are the same.
-front mount intercoolers are popular, but a side mount may be more beneficial to your "low" boost. The side mount means you have to get the smaller radiator as well. You could probably trade your p5 radiator with a MSP owner that went FMIC.
-The MSP came with a Garrett T25. Popular upgrade is the T28. If you go with a T28, do NOT run 7psi on the stock internals.
-you will need some sort of engine management. Options are MSP ECU, "piggyback" or "standalone". I personally would recommend a piggyback, as the MSP ecu sux. Standalones are a PITA as well.

Hey, I also just noticed you're in PSL! That's pretty close to me (hour and a half). There are a bunch of us (6 or 7?) down here that could help when you do do this.
 
I'll def. hit you guys up when it comes time. I'm looking at the Hi-boost kit, says everything's included. Didn't realize a sidemount intercooler is better for low boost. I was going to also be buying a turbo timer and afew gauges. I am hoping to sell my bike today after work, and in which case I'll be taking care of the suspension, short shifter, and an AWR front motor mount.

I'll keep doing some research though turbo kits and setups for me





Tylor
 
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Well, there are two "trains of thought". Some say the FMIC is better, some say the SMIC is better. Here are the facts:

-The FMIC will cool more air in any given time interval because of the shear size of the core. (meaning there is more volume in the core for heat tranfer to occur)

-The SMIC is a smaller core, therefore will not be as "efficient" in terms of heat transfer.

However, because there is more volume in the core of a FMIC (as well as the extra volume from "more" piping) there will be a, for lack of a better word, "pressure" drop using a FMIC. Your main goal is to consider air flow, also known as mass flow. However, standard practice dictates we use terms such as psi, rather than kg/s (or lb/s). This is also why a T28 at 7psi is different than a T25 at 7psi.

I don't know the exact numbers, although I imagine these following numbers will be generally accurate. I'll use standard terms for a better understanding. A stock MSP system will produce 6.5psi, through a SMIC (admittedly, the stock SMIC sucks). Without changing anything else, if you install a FMIC, you will see a "pressure drop" to a gauge pressure (meaning # + atmospheric pressure) of between 4.5 and 6 psi (depends on size of core, additional length of piping, cross-sectional area of piping, etc.). Yes, the air will be cooler, but it will not offset the difference of the forced induction. You will have to then up the boost to offset this pressure drop. Too much "cool" air and your fuel to air goes where it shouldn't = boom, hence the necessity of some sort of ECU.

Going with a FMIC will also cause a greater lag in the turbo, because more "potential" volume has been added that the turbo must charge and account for, before the air reaches the cylinder for combustion.

Going with the SMIC, the air won't be "as cool", but you will have better response with low boost applications. Higher boost will move the air faster (more air/mass per unit time), which will offset the change in volume that has been added by using a FMIC. As you get larger and larger in boost, FMICs become a necessity, because the air is moving so fast that the SMIC will not have time to actually cool the air. Hot charged air into an engine is bad (think diesel theory inside of a gasoline engine).

I hope all of this made sense. Sorry if this came off boring. At the end of the day, for low boost (I would recommend anything under 9psi on a T25) go with a SMIC.

As for the gauges, they are an "instinctive" must. A boost guage definately. Alot of people also get the "wideband" gauge which measure a detailed ratio of Air to Fuel.

In regards to the turbo timer, I had a "manual turbo timer". lol, I would just smoke a cigarette and let my baby purr for a few. They're not a necessity. That and it always bugged me that the car would continue to run after I left it. /shrug something just didn't seem right about that.

The Hi-boost kit is an awesome system. It's actually the only kit that I know of that is still around. They have a sister company down here in S. FL. I think the name is TBK (???) Fredo (Avarela86) works with them alot... just fyi.

If you have any questions when you're researching, let me know!
 
Nope, not boring. Quite informative actually. It never crossed my mind that the bigger the Intercooler, the dropin pressure. Hmm..

Totally a cosmetic thought though, but, a SMIC is stealthier. So, if the ricers can't see the intercooler, they won't want to race! Me likes that idea.

If I were to do a hiboost, is there anything you would add to/replace/upgrade from that kit?

Just realized, but, I should probably start rumaging around in the MSP section. Get more familar with our motors and boosting.

Thanks for your responses icespeed.

Tylor
 
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