Best turbo for torque

[sbeck]

What is the most torque a 2.0 has seen using a 14b, 16g, big t28 type fast spooling turbo? My car will never see a drag strip and since I use the car around town and on track days I am more concerned with torque than top end.

 

[Bud92gsx]

You will always get more hp than torque..Even the 1000whp club only has 6-700 lbs of tourque..I could be off on that estimate tho..

 

[gofer]

I was at RRE and saw a local LA DSM'r put down 311 ft-lbs/tq at 3100 RPM and 240 awhp running a t25 on E85 and cams. The left side of the screen is the torque graph and the right is horsepower, if you can read the numbers in the green blocks below thats what it did to the wheels on that pull.

 

[Luckybob2485]

I had a t28 with all supporting mods, fmic, exhaust, dsmlink, etc. On pump gas it put down 300 ft-lbs. at the wheels at around 21 psi. Very good for the street. Whp was around 270.

 

[Bud92gsx]

That's cool..E85 cams and a feaking t25 put down over 300..That's impressive..

 

[sbeck]

My stock t25 feels like it has no torque. I think its the original turbo with 125k miles though. After watching x-games yesterday I looked into that Citroen because I was curious and I found this

Driving the World's Best Rally Car

It claims that the car with a turbo 2.0 only makes 315 hp @5500 rpm but makes 420 fl lb. @ 2750rpm. I know the factory has pretty much unlimited budget for these cars but it seems crazy to have so much torque that low on a 2.0.

 

[gofer]

The first time I went to the dyno I had a small 16g and was running 91 octane, ended up with 282 ft-lbs/tq at 3600rpm and 260 awhp.

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[Bud92gsx]

Show off..I wonder why your getting more tourque than hp..I guess it all depends on tune..

 

[sbeck]

I was at RRE and saw a local LA DSM'r put down 311 ft-lbs/tq at 3100 RPM and 240 awhp running a t25 on E85 and cams. The left side of the screen is the torque graph and the right is horsepower, if you can read the numbers in the green blocks below thats what it did to the wheels on that pull.

I wonder if I turned up my fuel pressure to 4 bar if the evo injectors I have would be big enough for e85 on my t25. According to FIC's calculator with 260 hp and 58 psi along with compensating for the 30% difference I would not have a problem. Even at stock fuel pressure it comes out to just about 560cc.

Show off..I wonder why your getting more tourque than hp..I guess it all depends on tune..

I could speculate that with how they designed the 2g intake, tb, and heads with smaller ports it creates higher velocity resulting in more torque. I drag race my LS1 camaro and the first aftermarket heads were the AFR 205's that actually had smaller ports than some of the factory heads designed to give lots of street torque.

 

[donniekak]

Show off..I wonder why your getting more tourque than hp..I guess it all depends on tune..

Depends on where your torque peak is in the rpm range.
torque x rpm /5252 = horsepower

 

[sbeck]

I think before I head out to Willow Springs on the 14th I might see how my car reacts to e85 with the t25 before I decide to go 16g. 300 ft. lbs that low is really good.

 

[Bud92gsx]

I did forget about the 2g head..Damm me..I should have known that..

 

[sbeck]

I was at RRE and saw a local LA DSM'r put down 311 ft-lbs/tq at 3100 RPM and 240 awhp running a t25 on E85 and cams. The left side of the screen is the torque graph and the right is horsepower, if you can read the numbers in the green blocks below thats what it did to the wheels on that pull.

Did you know what kind and duration of cams he was using?

 

[gofer]

The E85/t25 setup had HKS 272 intake/exhaust cams and the 91oct/s16g setup had stock 2g cams.

 

[TunaTalon]

Depends on where your torque peak is in the rpm range.
torque x rpm /5252 = horsepower

This is for shaft measurements.

What the formula means is that below 5252 RPM torque will be higher than horsepower, and above 5252 RPM horsepower will be higher than torque. The formula is true for all engines from big A$$ diesels in train locomotives to destroked 2.1L DSM 4G6Xs.

For any engine; if HP peaks below 5252 RPM then peak torque will be higher than peak HP.

If the torque and HP curves on a dyno chart don't cross at 5252 RPM then the measurements are wrong.

 

[sbeck]

The E85/t25 setup had HKS 272 intake/exhaust cams and the 91oct/s16g setup had stock 2g cams.

Thanks for the info. I wonder if a 264/260 KELFORD setup might produce similar results as I have read that the HKS cams are the mildest based on the duration.

 

[gofer]

GSC S1's are a 268/268 grind that would be a good aftermarket cam for any t25/t28/s16g setup.

GSCS1 Cams

GSC Power Division S1 Cam Specs

 

[sbeck]

They look very close to the Kelford. Kelford uses higher intake lift with slightly less intake duration and an identical exhaust profile on there 264/260. I bet they both would be good and likely produce near identical results.

Does a 14b spool up faster than a small 16g?

 

[PieEyedPiper]

Gofer, do you know how much of boost was used to achieve that T25 score?

 

[DSMTyson]

They look very close to the Kelford. Kelford uses higher intake lift with slightly less intake duration and an identical exhaust profile on there 264/260. I bet they both would be good and likely produce near identical results.

Does a 14b spool up faster than a small 16g?

Yes, but it heat soaks over 20psi unless you have meth injection to cool the air off somewhat. The small 16G is more efficient than the 14b at higher boost levels, the 14b is more efficient than the small 16g at lower boost.

 

[gofer]

Gofer, do you know how much of boost was used to achieve that T25 score?

17psi. Thats snap your neck torque it hits so fast, then you can relax after because the t25 can't keep up.

 

[JusMX141]

Small turbos are definitely the torque-monsters because of the area at which they make the most airflow.

Horsepower and torque numbers are always the same at 5250rpms- so it comes down to whether you prefer a turbo that makes a punch of torque down low but doesn't pull for shit above 5k (most stock-framed turbos fit this description), or something that pulls longer and trades a little torque for some top-end pull. The turbos which don't pull well on top will normally give you higher torque than HP because the torque is made before 5250rpms and there isn't enough airflow after that to generate high horsepower numbers. By choosing a large turbo which doesn't even make boost until nearly 5000rpms, obviously your torque numbers are going to be rather poor.

A recipe for torque would be a 2.3 or 2.4 stroker with a turbo like a 20G or 68HTA making boost in the mid-20s. The additional displacement will aid in moving the turbo's torque curve lower than it would be on a 2.0, and you'll still have much better top-end power than a 2.0 with a T25.

I can't remember where I saw it, but a while ago I saw a dyno chart for an Evo III-powered stroker and it made over 400lb/ft somewhere in the 4500-5000rpm range at around 25psi. On the street, that had to feel like getting rear-ended by a semi. Now had that car owner swapped to, say, a GT35R- the HP numbers would have ended up much higher, and the torque numbers would undoubtedly have suffered or stayed nearly the same.

 

[Steve93Talon]

Here's my 14b power curve, this is a 2300 lb FWD car. E85 and around 23psi peak. Stock head/cams/intake, just a FMIC, DSMlink V3 SD, full 3", pump/injectors, and a 2600/4 puck/aluminum flywheel.

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[JusMX141]

^ Nice graph for that example. Big torque numbers that show the turbo pulls hard from 3k-4k, then begins to drop off sharp after the HP and torque plots cross at 5250. The turbo doesn't generate enough airflow to keep the HP numbers up in the higher rpms.

Still a great chart for a 14B!

 

[1990AWD]

Here's my 14b power curve, this is a 2300 lb FWD car. E85 and around 23psi peak. Stock head/cams/intake, just a FMIC, DSMlink V3 SD, full 3", pump/injectors, and a 2600/4 puck/aluminum flywheel.

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Good job on those numbers!

I'm going to be running a similar setup for a while here, but on pump gas with possibly water/meth. I'd be jumping for joy if I could get close to those levels!

Back on topic, torque is inversely proportional to speed, meaning the lower the RPM, the higher the torque. For our cars that a little different because we're boosted, but the same principle applies.