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Turbo opinion and streetability??

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Yeah that's a old sig LOL. Yeah I will make the same power with less boost and have better transient response but only be able to run x amount of boost compared to a lower compression engine. Yeah no matter what 40lbs/min is about how much it takes to make 400whp(which by the way it's fwp not awhp for me ;) ) I am treading in uncharted waters so I kinda don't have much to go off of as no one has ever tried to make this kinda power with 10:5:1 compression. I know of one guy on 2gnt but I don't think he was making this much power. There is actually another tuner doing a build even bigger than mine but when he's ready to talk about that he will.
 
Yeah that's a old sig LOL. Yeah I will make the same power with less boost and have better transient response but only be able to run x amount of boost compared to a lower compression engine. Yeah no matter what 40lbs/min is about how much it takes to make 400whp(which by the way it's fwp not awhp for me ;) ) I am treading in uncharted waters so I kinda don't have much to go off of as no one has ever tried to make this kinda power with 10:5:1 compression. I know of one guy on 2gnt but I don't think he was making this much power. There is actually another tuner doing a build even bigger than mine but when he's ready to talk about that he will.

I am going down the wrong path - (comparing apples to oranges) however I have a 2.5l with 10:1 compression in my EVO IX... I was able to make over 400 WHP on a non BB 50 trim, to4e compressor cover with a .63 a/r T31 turbine housing (STG III turbine wheel).

This was done at 15-16 PSI on pump gas and no meth injection.

If you need a budget turbo - you would be hard pressed to find a better one IMO.

Mike Huml
Slowboy -
 
I am going down the wrong path - (comparing apples to oranges) however I have a 2.5l with 10:1 compression in my EVO IX... I was able to make over 400 WHP on a non BB 50 trim, to4e compressor cover with a .63 a/r T31 turbine housing (STG III turbine wheel).

This was done at 15-16 PSI on pump gas and no meth injection.

If you need a budget turbo - you would be hard pressed to find a better one IMO.

Mike Huml
Slowboy -

LOL actually I already know. I called there today askin about the SBR-G50ET and told them my dilema and they started telling me about your car. Yeah the thing that scared me was that you made what I made on a stroker so it kinda put things in context with how big of a turbo I needed to do this or how much boost it would take.

Of course I would get a t3 (essentially a s258) which by the way everyone I dind't put t but I have a t3 log style manifold that I'm gonna get a wastegate flange put on for whichever wastegate size I need to regulate my desired boost for my desire dturbo.
 
Ok let me be more reasonable and list the mods in a easy to read form in case my profile is kinda confusing:

97 eclipse GS 420a motor
10:5:1 Weisco Pistons
Eagle H beam rods
Ported and polished head
Obx intake manifold port matched
Q45 TB
Crower Stage 2 3/4 race cams
Crower spring/retainer kit
3" full N1 Style exhaust(no cat)


The main factors that are making this a harder call is teh 10:5:1 compression and stage 2 cams

From talking to SBR and a couple other companies it looks like 15-17psi is the max that can be run without dealing with crazy knock on 10:5:1 compression on pump gas. So unless I get meth injections the turbo I pick has to make the power i'm looing for at those psi levels. I really think meth migt be my only option on this.

What are you running for a crank?
 
LOL actually I already know. I called there today askin about the SBR-G50ET and told them my dilema and they started telling me about your car. Yeah the thing that scared me was that you made what I made on a stroker so it kinda put things in context with how big of a turbo I needed to do this or how much boost it would take.

Of course I would get a t3 (essentially a s258) which by the way everyone I dind't put t but I have a t3 log style manifold that I'm gonna get a wastegate flange put on for whichever wastegate size I need to regulate my desired boost for my desire dturbo.

If you need help or want to chat - just give me a call... I would be happy to chat turbo talk with you... very cool build you have going on... congrats... the 420A is a great motor when built properly... kudos to you for taking it on! :thumb:

Mike Huml
Slowboy -
 
If you need help or want to chat - just give me a call... I would be happy to chat turbo talk with you... very cool build you have going on... congrats... the 420A is a great motor when built properly... kudos to you for taking it on! :thumb:

Mike Huml
Slowboy -

Thanks. I have got crazy lucky so far with this whole build. I started off just wanting a every day I/H/E car then I was gonna save up and buy another 1g tsi but then I started finding deals on stuff and hear I am. I think I may have found a great deal on a turbo to. I just don't see why 420a guys don't make big power too so I'm gonna try and break people out of the sterotype that all Nt's are slow. :dsm::talon::laser:
 
Oh thats good to know. It probably won't matter anyways though.... with that high-comp 420a set-up, you probably won't reach high enough power for that to matter. My guess is that the stocker @ 300hp would be fine.

I wrote you the best advice any one could give you regarding your motor, but I guess the mods took it off because it was too direct (it was about you ditching the 420a, so that you can make your goal of 400whp on pump gas) ....did you get a chance to read it before they deleted it?

Have you thought about engine management yet? DSMLink would probably work real good for you since you're staying under 500. AEM EMS is probably a little too advanced, and over kill for you
 
Oh thats good to know. It probably won't matter anyways though.... with that high-comp 420a set-up, you probably won't reach high enough power for that to matter. My guess is that the stocker @ 300hp would be fine.

I wrote you the best advice any one could give you regarding your motor, but I guess the mods took it off because it was too direct (it was about you ditching the 420a, so that you can make your goal of 400whp on pump gas) ....did you get a chance to read it before they deleted it?

Have you thought about engine management yet? DSMLink would probably work real good for you since you're staying under 500. AEM EMS is probably a little too advanced, and over kill for you

STOP POSTING !!! Please just stop because it's all either wrong or bad. I can't use dsmlink it's for 4g63's EMS is not to advanced for me I have messed with it already. Not to mention I already have a tuning setup in the works. I'm not ditching my 420a so agian STOP POSTING!!

And yes I read all your post
 
Awh man I'm sorry. I don't want you upset over my little mistake. I didnt know that DSMlink didnt work with 420a.... I don't have much experience with tuning that motor.

I was asking what tuning you're going with? (and just trying to add a little friendly advice thats all). I didnt know that you were a seasoned vet. You have been asking so many questions I just figured you were a noob ...my bad

Since you deciding not to ditch your current NA motor.... Are you going to change your "400whp on pump gas" goal since it's not attainable?
 
Awh man I'm sorry. I don't want you upset over my little mistake. I didnt know that DSMlink didnt work with 420a.... I don't have much experience with tuning that motor.

I was asking what tuning you're going with? (and just trying to add a little friendly advice thats all). I didnt know that you were a seasoned vet. You have been asking so many questions I just figured you were a noob ...my bad

Since you deciding not to ditch your current NA motor.... Are you going to change your "400whp on pump gas" goal since it's not attainable?

Yeah now it's 450 on meth and and pump
 
Yeah now it's 450 on meth and and pump
I always remember Buschur saying make sure the intercooler is not undersized,and that whatever tubocharger you get the larger the turbine wheel/turbinehousing,the easier it is to tune the car at high boost levels and keep your motor detonation free. Why would you need meth if these things apply in your situation?

I thought you also posted a pic of a 7blade Holset turbo that you were going to use?:confused:
 
I always remember Buschur saying make sure the intercooler is not undersized,and that whatever tubocharger you get the larger the turbine wheel/turbinehousing,the easier it is to tune the car at high boost levels and keep your motor detonation free. Why would you need meth if these things apply in your situation?
Because pump gas has it's limits. So does the truth behind Dave's tech advice.
 
I always remember Buschur saying make sure the intercooler is not undersized,and that whatever tubocharger you get the larger the turbine wheel/turbinehousing,the easier it is to tune the car at high boost levels and keep your motor detonation free. Why would you need meth if these things apply in your situation?

I thought you also posted a pic of a 7blade Holset turbo that you were going to use?:confused:

I did this whole thread is kinda irrelevant now but I was just respondin since someone posted in here. I have high compression that's why it's not 100% true because this engine and high boost will never meet. WIth meth I might be able to get 20psi with whose tuning the car. 2psi on my h40 should net me the power i'm looking for. To be honest I think people get caught up in power to much anyway. I want wide powerband no boost fall off and traction that the average awd guy has. I haveso much weight reduction and plans for even more that I will do what people with plenty more hp do.
 
Have you ever thought about using nitrous Slipp? Maybe just a 25-50shot? That would be around 40-70whp on a turbo motor. The Icy cool n2o would allow you to run a little more boost too. Wide powerband, and max power don't mix very well. If you get a big turbo for max power then you won't have wide powerband. <-Nitrous will fix that :) I use to be a nitrous guy before I ran turbo's ....I had it on 3 different cars. Its great stuff and easy to tune ....not scary like most people think.
 
I did this whole thread is kinda irrelevant now but I was just respondin since someone posted in here. I have high compression that's why it's not 100% true because this engine and high boost will never meet. WIth meth I might be able to get 20psi with whose tuning the car. 2psi on my h40 should net me the power i'm looking for. To be honest I think people get caught up in power to much anyway. I want wide powerband no boost fall off and traction that the average awd guy has. I haveso much weight reduction and plans for even more that I will do what people with plenty more hp do.

HMMM, boost and compression only raise the rate of burn. Which LEADS to detonation. It's not that it directly causes it.

Let me say this based on your private goals which we've discussed in PM.

High CR means that the fuel/air mixture burns faster. 93 octane means the same thing. Timing the spark to the burn rate is all that's needed. Unless you're running high enough CR to preiginite the fuel (like +22:1). Then the higher CR isn't a cause of knock. A timing curve that doesn't go along with the faster burn rate is a cause. Pulling lots of timing retard with a fast burn rate doesn't lose lots of power. Infact, firing the air/fuel mix later because you have to time with how fast the burn rate is just means their is LESS pumping loss, resistance to the piston, during the compression stroke. The compression stroke shows the most pumping loss and affecting the loss here does the most. So full timing control and high compression with a good tuner or plenty of dyno time will net you lower Brake Specific Fuel Consumption.

The same goes for boost in a lesser sense. Buscher boasts of running gt35R powered evos with +8.8 CR with pump gas and 30 psi using apropriate timing changes. High power is still there even with HIGH timing retard.

Lower BSFC means more power per unit airflow or fuel flow. This is where big pumpgas numbers can be seen. Less boost or airflow is neccesary to achieve a certain power.

A better flowing turbine will net more power without the need to raise the boost because thesytem VE goes up. Better VE means less pumping loss AND more air without heat ,which high boost yields. But as mentioned, this means lag. A twinscroll setup will negate alot of the slow spool. Also, a very efficient turbine wheel and compressor wheel will negate slow spool because not as much turbo rpms will be needed to reach a certain flow. An efficient pair of wheels will also assist in peak flow, overall VE, pumping loss, and BSFC because more gases can be simply shunted to the wastegate uninhibited.

IMHO, you're on the right path as you are looking at the more efficient borge-warner and holset turbos. A more efficient engine (high CR, high VE, low pumping loss) loves an efficient turbo. Without an efficient turbo, it's pretty difficult to show the benefits of the efficient engine. This is why many tell you to run low compression with high boost and high timing to achieve mid/high power. They don't choose an efficient enough turbo.
 
HMMM, boost and compression only raise the rate of burn. Which LEADS to detonation. It's not that it directly causes it.

Let me say this based on your private goals which we've discussed in PM.

High CR means that the fuel/air mixture burns faster. 93 octane means the same thing. Timing the spark to the burn rate is all that's needed. Unless you're running high enough CR to preiginite the fuel (like +22:1). Then the higher CR isn't a cause of knock. A timing curve that doesn't go along with the faster burn rate is a cause. Pulling lots of timing retard with a fast burn rate doesn't lose lots of power. Infact, firing the air/fuel mix later because you have to time with how fast the burn rate is just means their is LESS pumping loss, resistance to the piston, during the compression stroke. The compression stroke shows the most pumping loss and affecting the loss here does the most. So full timing control and high compression with a good tuner or plenty of dyno time will net you higher Brake Specific Fuel Consumption.

The same goes for boost in a lesser sense. Buscher boasts of running gt35R powered evos with +8.8 CR with pump gas and 30 psi using apropriate timing changes. High power is still there even with HIGH timing retard.

Higher BSFC means more power per unit airflow or fuel flow. This is where big pumpgas numbers can be seen. Less boost or airflow is neccesary to achieve a certain power.

A better flowing turbine will net more power without the need to raise the boost because thesytem VE goes up. Better VE means less pumping loss AND more air without heat ,which high boost yields. But as mentioned, this means lag. A twinscroll setup will negate alot of the slow spool. Also, a very efficient turbine wheel and compressor wheel will negate slow spool because not as much turbo rpms will be needed to reach a certain flow. An efficient pair of wheels will also assist in peak flow, overall VE, pumping loss, and BSFC because more gases can be simply shunted to the wastegate uninhibited.

IMHO, you're on the right path as you are looking at the more efficient borge-warner and holset turbos. A more efficient engine (high CR, high VE, low pumping loss) loves an efficient turbo. Without an efficient turbo, it's pretty difficult to show the benefits of the efficient engine. This is why many tell you to run low compression with high boost and high timing to achieve mid/high power. They don't choose an efficient enough turbo.


Yeah but even slowboy with their shop evo with 10:5:1 could only squees 15psi out of their old borg setup and like 19psi out of the new setup? I would love to run 20psi because I know at 20psi with my compression this turbo would be everything I need it too. Maybe with A LOT of timing pulled and meth I might be ok but not running enough timing will make it spool slower unless I lower it so much that egt's raise and then it would spool faster.
 
Have you ever thought about using nitrous Slipp? Maybe just a 25-50shot? That would be around 40-70whp on a turbo motor. The Icy cool n2o would allow you to run a little more boost too. Wide powerband, and max power don't mix very well. If you get a big turbo for max power then you won't have wide powerband. <-Nitrous will fix that :) I use to be a nitrous guy before I ran turbo's ....I had it on 3 different cars. Its great stuff and easy to tune ....not scary like most people think.

I ran a zex kit on my mk3 supra which was boosted too but that will complicate things even more. I'm not a big fan of letting other people tune my car but I think i'm gonna take a trip up to PA and let nate from TGP tune it on they dyno.
 
I did this whole thread is kinda irrelevant now but I was just respondin since someone posted in here. I have high compression that's why it's not 100% true because this engine and high boost will never meet. WIth meth I might be able to get 20psi with whose tuning the car. 2psi on my h40 should net me the power i'm looking for. To be honest I think people get caught up in power to much anyway. I want wide powerband no boost fall off and traction that the average awd guy has. I haveso much weight reduction and plans for even more that I will do what people with plenty more hp do.
Because pump gas has it's limits. So does the truth behind Dave's tech advice.

My fault for not clarifying! Don't get confused.
I'm not saying that you need to go high boost Slippi. My thinking is that since you have high compression I would apply the bigger intercooler,bigger turbine/turbine wheel, modest boost level idea ,because the car would be easier to tune. I was only posting verbatum what Dave mentions in turbo magazine which would obviously apply to a lower compression motor as far as high boost is concerned.

I think,low compression+high boost and proper sized intercooler means easy to tune
Just as high compression +lowboost and proper sized parts just like in the low boost example(big) ,means easy to tune.
 
or plenty of dyno time will net you higher Brake Specific Fuel Consumption.

Higher BSFC means more power per unit airflow or fuel flow.

Matt, that's a really great post with a ton of good info. There's just one thing I think you accidentally misspoke about that I'd like to try to clarify...

BSFC, brake specific fuel consumption, is a measure of the weight of fuel (in pounds) that an engine uses per hour for each horsepower it produces.

Lower BSFC, not higher, is better and means the engine is more efficient. Naturally aspirated engines usually have a BSFC of around 0.45-0.50, turbocharged and supercharged engines generally have BSFC of between 0.55-0.65, likely because of the richer mixtures needed for fuel cooling of the hot air charge. However combining high CR and moderate boost with correct timing and fueling will likely push the BSFC down at least close to the typical N/A values, just as you alluded to.
 
Yeah I'm going with a t3 .70ar because while I want power I do not want to sacrafice drivability. I want to look into meth but I don't want to make tuning any harder than it already is going to be. Monster said in one thread don't knwo if it was here or not that he didn't see HUGE gains between pure water injection and meth/water mix so I might try just water and 93 octane see how that works out for me. 20psi is my goal in how much I would like to run. Wether I can or not time will tell but that would make the setup shine I believe. You know what they say life starts at 20psi
 
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