matching HP & TQ... question as well as turbo needed.... Please and thank you.

[Pblesh85]

What does it take to achieve matching numbers or close to it ? So I know it has alot to do with tuning and part selection. But what are some main factors that go into matching hp/tq ?

I hate seeing a dyno chart with 700hp and 487ft lbs. I am retarded to the technical side of tuning, and would appreciate it if someone could put it into terms that are easily understood. I am trying to find out if it is mainly tuning or more parts selection.

I have a goal in mind and I know it can be achieved. Im looking to make 450hp/400ft lbs. My motor is done for the most part but there are a few things I still need. So in part this is to help buy what I need and not so much what I want. I dont want to buy anything I dont really need.

The piece I am missing in my build is a turbo. I really have no idea what will yield the end result im looking for. Here is a break down of what i have.

s14 sr
wiesco pistons 8.5-1
eagle rods
polished and balanced crank
arp head/rod/main bolts
apex 1.1
bc 264's, valve spring, retainers,
circuit sports ras
nismo 740cc
greddy intake manifold
greddy fmic
greddy pulleys
greddy o2 dump/down pipe
power fc d jet with boost up kit.

I am currently running a garrett 2560 on a tomei manifold @1.0 bar

I have it tuned(Doug at UP) but im not sure of the #'s because the dyno is not calibrated. maybe 300~350ish...

I have a top mount manifold I plan on using with a tial f40 that is flanged for a t3 setup. But no idea what turbo I want or need to run.

I drift primarily and attend track days. So boost response is key. and I run 92oct

Does anyone have any suggestions on a turbo or answers to my first questions ?

[The Dude]

If you're wanting 450whp then a GT30R is probably as small as you could go, although that may be pushing its limits.

You need an EGT gauge if you don't already have one. Also need to have some more time on the dyno to get your timing right.

[Pblesh85]

I dont have an egt but I do have a wideband.

I like the tomei turbos but they are all internal wastegate and bottom mount if im not mistaken. the 8270 had my eye but was not going to work with my setup. A 30 series was my next option.

[JFoxx]

on my old motor i was making 389hp with 365ft/lbs

[Synergy]

Your build is pretty much identical to mine.

I choose a gt2871r with a hta73 wheel in a .64 t3 housing. I'm shooting for a hair over 400whp with crazy response.

As far as matching hp to torque.... Hp is a made up figure based on torquexrpm/5250 with that being said cars that have high hp but low torque is because the motor spins up well past 5250 and most likely peak torque falls after the 5250 mark. You should notice all dynos hp and torque intersect at 5250

[jr_ss]

You need to get rid of the greddy manifold. You'll need a long runner intake manifold if you want to keep peak trq numbers up. To be honest the S13 SR intake manifold is good to the 500hp mark. Just slap a large throttle body on it.

[Pblesh85]

I have the older greddy manifold. Its just the upper plenum. So aside from a bit more volume and improved runner/port flow it should be near the same as the stock setup right ??

Is there a difference between the straight runner style(new) and the older one in terms of power ?

Why would it hurt me to keep it ?

I planned on switching to the new one so I can run top feed injectors and a greddy rail.

Here is my setup(different chassis now and a tomei manifold). But there will be a few revisions soon.

My setup:
http://i105.photobucket.com/albums/m205/Pblesh85/new%20paint/2011-09-17154615.jpg
http://i105.photobucket.com/albums/m205/Pblesh85/new%20paint/2011-09-17154521.jpg
http://i105.photobucket.com/albums/m205/Pblesh85/new%20paint/2011-09-17154451.jpg

[Pblesh85]

I also have a q45 tb that is not installed. When does it become necessary to need that upgrade ? What do I gain from it and what do I loose from it ?

I will assume better throttle response and more air into the intake. But I have never really understood this.

[jr_ss]

Typically speaking, if you want to keep/increase torque you want a long runner intake manifold.

I assumed that you had the short runner style manifold, which as dicussed above, is optimized for hp not trq. Keep your manifold setup as is and grab a manifold spacer from Mazworx. You'll then be able to run top feeds if you'd like. However, Sard 850cc sidefeed's will give you plenty of fuel for your goal. I'd swap the Q45 on when you can, you may have to modify the upper plenum to bolt it on. It's a huge piece.

Here is a good article on intake manifolds... Read up

Intake Manifolds: From Mild to Wild: Engine Builder (http://www.enginebuildermag.com/Item/3107/intake_manifolds_from_mild_to_wild.aspx)

[Pblesh85]

that was a good article, I feel it is a bit broad and geared towards v8's but answered a question or two.

So wouldnt the newer manifold out perform the old ? The runners are straight and would flow smoother/more direct. The length is about the same, is it not ?

[steve shadows]

If you want equal HP to TRQ get a V8 or a L6 and drop that in.

You're not going to get 700 WHP and 700 WTRQ out of a 2 litre 4 cylinder with backyard build mods.

The closest option is something like a 2.2 litre stroker kit+ a GTX3076R + 264 CAMS and a lot of fine tuning and dyno time on a steady state capable dyno like the dyno dynamics. You'll be able to get around 350 WTRQ and 450 WHP with minimal lag but there will still be some lag and this would be on 91-93 octane if your tuner is a true ninja also. Gotta have the Q45 TB and some port polish matching work too to help as well.

[Pblesh85]

thats everyones easy way out, throw a v8 in it a cam and call it a day. Im staying true to the 4cyl

This motor was in a car that made 430 and 397 on pump(has since been redone and refreshed). It was a little different setup than I want to do. So I know im not far off.

My main question is what causes the huge difference between HP & TQ

I have also seen plenty of 2.0L that make what I have in mind. I may not be BALLER status, but im far from backyard build. I want to understand a bit more and am only looking for helpful advice or view points.

Thanks for the time you took to read my thread, but if you are only going to suggest I dump my 10k + investment to buy a V8... Please stay off my thread.

[godrifttoday]

No one mentioned taller gears....

[The Dude]

Sounds like he had pretty good advice.

[LuckyX2]

I'm confused why you even want matching torque and horsepower numbers...

That only happens when your torque falls off at higher RPMs.
With a flat torque curve (which is desirable) horsepower will always have a higher peak than torque.

[steve shadows]

thats everyones easy way out, throw a v8 in it a cam and call it a day. Im staying true to the 4cyl

This motor was in a car that made 430 and 397 on pump(has since been redone and refreshed). It was a little different setup than I want to do. So I know im not far off.

My main question is what causes the huge difference between HP & TQ

I have also seen plenty of 2.0L that make what I have in mind. I may not be BALLER status, but im far from backyard build. I want to understand a bit more and am only looking for helpful advice or view points.

Thanks for the time you took to read my thread, but if you are only going to suggest I dump my 10k + investment to buy a V8... Please stay off my thread.

I know but you're dropping numbers like 700 WHP with 400 TRQ and saying why can't I have 700 HP and near 700 WTRQ with a 2 liter 4 cylinder...that's where my advice was coming in...Yes it's the easy way out but if you MUST have linear flat torque to power and that's your life goal then you really need more displacement and preferably at least 2 more cylinders....From personal experience here tuning hundreds of cars over 10 years. :trogdor:

[steve shadows]

I'm confused why you even want matching torque and horsepower numbers...

That only happens when your torque falls off at higher RPMs.
With a flat torque curve (which is desirable) horsepower will always have a higher peak than torque.

I don't think he means literally matching just close numbers overall...but yes you also raise a great point here too.

[steve shadows]

I also have a q45 tb that is not installed. When does it become necessary to need that upgrade ? What do I gain from it and what do I loose from it ?

I will assume better throttle response and more air into the intake. But I have never really understood this.

MUCH better throttle response, more power down load high everywhere...not really sure what you lose from it...I didn't lose anything car just ripped like a bat out of hell afterwards. Also if you can somehow make it work with the stock redtop intake manifold then you'll have even MORE insane response...then pair that up to a twin scroll or ball bearing GTX2871R or GTX3076R and you're flying...serious fing business, response and good torque and hp numbers all across...:s101:

[eflove]

Now i'm not close to your goal but I almost have the same HP & TQ. It has room for more too. You wont make 450 on a gt28 but you could make 400 and I think you will like it more than a bigger turbo. You could always go with a stroker motor to make a lot more TQ. My motor has VTC fyi.
http://i10.photobucket.com/albums/a135/eflove/e85dyno.jpg

[Synergy]

Rthats everyones easy way out, throw a v8 in it a cam and call it a day. Im staying true to the 4cyl

This motor was in a car that made 430 and 397 on pump(has since been redone and refreshed). It was a little different setup than I want to do. So I know im not far off.

My main question is what causes the huge difference between HP & TQ

I have also seen plenty of 2.0L that make what I have in mind. I may not be BALLER status, but im far from backyard build. I want to understand a bit more and am only looking for helpful advice or view points.

Thanks for the time you took to read my thread, but if you are only going to suggest I dump my 10k + investment to buy a V8... Please stay off my thread.



Did you read my post.... Your hp equal to torque is a moronic quest BECAUSE hp is a fake number made up byrpm and torque. Its simple. If peak torque is after 5250 it will have more hp than torque. Want more torque set your rev limiter to 4k. I wish they never posted hp numbers on dynos. If you can't figure out a power band by torque+rpm dont modify cars.

[Pblesh85]

I was using 700 as an example, not a literal number. I have a decent number I want, but it is not really outrageous.

[Pblesh85]

I'm confused why you even want matching torque and horsepower numbers...

That only happens when your torque falls off at higher RPMs.
With a flat torque curve (which is desirable) horsepower will always have a higher peak than torque.

I want an overall flat curve without having to rev the piss out of my engine. I would like to be able to break loose without having to completely lay into it. Id also like as much power & torque as I can get with out having to spend a SHIT LOAD on an extreme build. I dont want your typical turbo that will spool up to 500 and not hit full boost til 5k+

I want something similar to the response of a 28r but that has a bit more to breath at the higher end.

[Pblesh85]

R



Did you read my post.... Your hp equal to torque is a moronic quest BECAUSE hp is a fake number made up byrpm and torque. Its simple. If peak torque is after 5250 it will have more hp than torque. Want more torque set your rev limiter to 4k. I wish they never posted hp numbers on dynos. If you can't figure out a power band by torque+rpm dont modify cars.

Yes I have heard that about 5250, I dont really understand it completely or why. But I have heard it talked about. Yes I do know what a power band is and im trying to have a bit more than 2k worth of one.

From what I have seen or noticed alot of cars that make good power out of a 4cyl do it in higher rpms. Their power band also seems small. Cars that are built and detuned to have better response or a flat curve seem to be more efficient and not have to work as hard.

I guess my overall goal is to have something similar. Good top end with out sacrificing low to mid, and not have to run my engine to full capacity.

Now as far as understanding the ins and outs of actually tuning the car... I have no idea what is involved other that mapping fuel and air. I dont know why you add or take away, when you mess with timing, ect... So if I sound like an idiot, sorry. I am just trying to better understand in a less technical fashion.

[Pblesh85]

Now i'm not close to your goal but I almost have the same HP & TQ. It has room for more too. You wont make 450 on a gt28 but you could make 400 and I think you will like it more than a bigger turbo. You could always go with a stroker motor to make a lot more TQ. My motor has VTC fyi.
http://i10.photobucket.com/albums/a135/eflove/e85dyno.jpg

i dont think im very far off what you have already. And i love the response, I just want a bit more top. My thought process is, "if my power goes up, why cant torque ?".

And 400 is not bad or far off what I want. I just have that imaginary number in my head. Whether it is dumb or not, its what id like.

We all have goals for our car. I dont like to settle on things or hear that I cant have something.

[RastaS14]

I want an overall flat curve without having to rev the piss out of my engine. I would like to be able to break loose without having to completely lay into it. Id also like as much power & torque as I can get with out having to spend a SHIT LOAD on an extreme build. I dont want your typical turbo that will spool up to 500 and not hit full boost til 5k+

I want something similar to the response of a 28r but that has a bit more to breath at the higher end.

It sounds like you are describing the V8 powerband. But a similar, linear powerband can be achieved with proper turbo sizing/piping/supporting mods and tune. Do some reasearch, more in-depth research on flow rates per turbo design. Also take into account the Inducer/Exducer ratio per turbo, the turbine design and form of bearing. The A/R ratio plays a lot into the overall turbo response, full boost range and torque curve; provided everything in the setup is calculated appropriately and proportionally.

A lot of people spend more time focused on what the turbo can push in terms of max hp, but a lot more can be done for a good overall balance of power/torque delivery when attention is given to the sizing and flow-rates of the setup at hand.

Just some food for thought. I'm sure some more knowledgeable individuals can touch on this subject as well.

[Pblesh85]

It sounds like you are describing the V8 powerband. But a similar, linear powerband can be achieved with proper turbo sizing/piping/supporting mods and tune. Do some reasearch, more in-depth research on flow rates per turbo design. Also take into account the Inducer/Exducer ratio per turbo, the turbine design and form of bearing. The A/R ratio plays a lot into the overall turbo response, full boost range and torque curve; provided everything in the setup is calculated appropriately and proportionally.

A lot of people spend more time focused on what the turbo can push in terms of max hp, but a lot more can be done for a good overall balance of power/torque delivery when attention is given to the sizing and flow-rates of the setup at hand.

Just some food for thought. I'm sure some more knowledgeable individuals can touch on this subject as well.

Its not that I have not read up on it. I dont understand it. I am not an auditory learner so I have a hard time if I cant see it actually happening. Im not dumb, quite the opposite, I just cant seem to grasp what it takes and why.

I just need it "dumb-d" down a bit.

[EDacIouSX]

Well I always thought torque was the force exerted on something at 90 degrees and figured that had to do something with the TQ numbers on a motor. But... I really don't know much about how it's calculated... I just always kind of guessed that's what it was...

Anyway, You can't really have the best of both worlds with what you are asking for. You can minimize the lag for what you want but if high horse power engines with tons of torque were easy to do then everyone would do it. I know I'm not adding much but I am just telling you to not get your hopes up cause I don't think it's possible haha.

[Synergy]

Well I always thought torque was the force exerted on something at 90 degrees and figured that had to do something with the TQ numbers on a motor. But... I really don't know much about how it's calculated... I just always kind of guessed that's what it was...

Anyway, You can't really have the best of both worlds with what you are asking for. You can minimize the lag for what you want but if high horse power engines with tons of torque were easy to do then everyone would do it. I know I'm not adding much but I am just telling you to not get your hopes up cause I don't think it's possible haha.



Torque is the amount of force that's applied. Rpm in thus cass is the distance and hp is the result of the torque over rpm.

Back to OP your in the same boat as i am. My goal was 400 to 450whp fastest spool possible.
My solution was to take my gt2871r t2 .64 and send it to forced performance to get a 73mm billet hta wheel.
This bring cfms from 43lbs to 54lbs. I'm also switching to a t3 .64 housing to hopefully combat the pressure ratio differences.

I should have spool equal to a gt2871r but it will hold the torque higher into the rev range. That will cause me to have more hp than torque BUT i will still make 300ft lbs from 3700+ giving me a super beefy powerband.

[Pblesh85]

id like to hear how that works out for you. When will that become reality ?

[Synergy]

id like to hear how that works out for you. When will that become reality ?

Motors being assembled as we speak. Tune should be in a few weeks. I figure if people hit 400whp on gt2871rs i don't see why a 9.1 comp with a ve head fully built with all bolt ons rev limited to 8k can't put out 425whp.

The hta73 wheel actually spools quicker than a gt2871 more like a gt28rs. But since I'm going t3 my spool will be very similar.

Go with the setup i just listed or go gtx3071r twinscroll if dollhairs are no issue.

Or be a super trooper get a gt28rs send it to fp have them put the hta73 on it with the t3 twinscroll housing and have stock spool 450whp.... I have yet to see any gt28 twinscroll setups i wonder how it would spool.