Dinan breaks the torque barrier

Post by **maxnix** » Thu Apr 24, 2003 7:33 am

Wait a minute! Torque says 149.8 ft. lbs. or 153.7 ft. lbs. in the notes (which is it?). So the 75 ft. lb. per liter seems pretty true, even if a drivetrain loss of 10 % is allowed. Measuring methods, especialy fudge factors, may be suspect here.

M5s are fast, but for how long? I don't seek them out, but I have never seen one with 100,000 miles. I am sure they exist, but at what maintenance expense?

Post by **EWT** » Thu Apr 24, 2003 7:33 am

maxnix wrote:Wait a minute! Torque says 149.8 ft. lbs. or 153.7 ft. lbs. in the notes (which is it?). So the 75 ft. lb. per liter seems pretty true, even if a drivetrain loss of 10 % is allowed. Measuring methods, especialy fudge factors, may be suspect here.

The 149.8 is just at one specified point in the curve. The max is 153.7. At least it's in the triple digits, that's pretty impressive for a Honda.

I've personally never understood the fascination with specific output. It matters in race series where displacement is limited, but for street cars, it's something for people with weak no-torque motors to brag about while going slow. Output matters, not specific output. Vipers have pretty low specific output, but still manage to go mighty fast. Just say no to small displacement, non-forced induction motors.

Quote »M5s are fast, but for how long? I don't seek them out, but I have never seen one with 100,000 miles. I am sure they exist, but at what maintenance expense? [/quote]

I've got a friend with one, and it's been pretty reliable. I think the basic drivetrain is stout, but like a lot of BMWs, it's the little things that break. It's an awesome car. It's just stupidly fast for a fairly big four door sedan. It make a Q45 feel like a diesel Kia by comparision.

Post by **cosmo** » Thu Apr 24, 2003 7:33 am

Q45tech wrote:Still a Q with just a JWT ecu [$695] delivering 337/4.494= 74.98 lb/ft per liter is still pretty impressive

Sorry, I don't know Q's but, with just an ECU you get 337 lb/ft of torque? How much hp?

That's nuts

Website · Post by **s13sr20chris** » Thu Apr 24, 2003 7:33 am

a 200hp na b20 cant be "lightly modded". i have no hands on experience with them, but i am under the impression that you would need more than bolt ons to get 200hp at the wheels even.

also, when did the m3 move up to the 333hp motor. i would think that version with the lighter weight and smaller package would waste an m5 on a road course. well bmws have always been good at delivering more than just the numbers so i could easily have been wrong there.

Post by **cosmo** » Thu Apr 24, 2003 7:33 am

It moved to a 3.2 liter 333 hp engine when they introduced the E46 in 02' (Don't quote me on year, but I'm pretty sure)

Post by **Def** » Thu Apr 24, 2003 7:33 am

E46 M3 came out in '01, but the M5 is usually faster on road courses from what I've seen. I drive an E36 M3, and while E46 M3's are cool cars, they're not so much an upgrade from my "watered down" M3 as many would call it. Anything other than a straight and I eat them up and my car is basically stock with 90hp less. They're just too heavy IMO.

The M5 is one badass machine though. RIDICULOUSLY fast for a 4000lb sedan, and somehow, they seem to corner pretty hard as well(at least as well as my car).

That B20 is actually pretty lightly modded. It has a VTEC head, but that's basically how the motor should have come from the factory.

It's a stock bottom end with a VTEC head and some mild cams(otherwise you run into piston to valve clearance problems) with good bolt-ons. Hondas really made great strides after there was some competition in the aftermarket. If you've got some money to spend, there are some AMAZING exhaust systems that will net crazy increases over even good aftermarket systems.

Website · Post by **s13sr20chris** » Thu Apr 24, 2003 7:33 am

i dont doubt your claim, but i have heard a lot of wild stuff from honda owners. i rarely see it backed up with respect to exaust systems. i have a friend with an sr20ve in his 98 sentra. with stock sr16 cams, i/h/e, pulleys, he has almost 200hp at the wheels. i have watched him pass a z06 at virginia international raceway on the short course.

Post by **Def** » Thu Apr 24, 2003 7:33 am

I've heard alot of crazy claims from Honda ricers, but the only people I still associate from that circle are enthusiasts.

The "really good" exhaust systems are far far different than your off-the-shelf $250 header and $400 catback. The systems I'm refering to are made by SMSP(I think that's it) or Hytech. The whole system(can't use factory catback, as the collector is pushed back so far it won't bolt up) costs right around $1500-1800 or so. Each system is custom made per car and engine setup, so wait time is long - but the results are stunning.

Post by **DAEDALUS** » Thu Apr 24, 2003 7:33 am

I just realized the G35 coupe makes 77+ ft-lbs/liter, with the 2005 model looking to put out even more. Dennis, do you expect to see a higher rate of failures under warranty with the 3.5L engine in these cars?

Post by **Q45tech** » Thu Apr 24, 2003 7:33 am

312-333 lb/ft is pretty much average now for the 4.2, 4.3, 4.4, 4.5 liter engines in the BMW, Audi, Jag, Lexus, Q V8 4 doors.

Noticed that the brand new V10 5.7 liter Porsche engine is at 76.3 lb/liter.

Really a function of real CR [volumetric efficiency] and bore size.

Back to 337 lb/ft with JWT ecu............not hard when the stock engine really makes 307 lb/ft...........10% is well within normal gains.............because the Q tuning is optimized at 5500 and 6,000 rpm..........hard to get much above 300-310 HP [that would be 271 lb/ft at 6,000 rpm]..........19.5% torque roll off at 6,000 rpm.

Post by **C-Kwik** » Thu Apr 24, 2003 7:33 am

DAEDALUS wrote:I just realized the G35 coupe makes 77+ ft-lbs/liter, with the 2005 model looking to put out even more. Dennis, do you expect to see a higher rate of failures under warranty with the 3.5L engine in these cars?

I'm thinking that the torque figures probably won't change much. I'd think they may shift the peak torque up to a higher RPM. OR at the least it will make some more torque at higher RPM than it does now. With peak HP being 280 at 6200 RPM, that's 237 ft-lbs of torque. To achieve 295 HP at the same RPM, it would need to make about 250 ft-lbs. Tuning the Variable Cam Timing a little differently at higher RPM might be enough. This would probably be the cheapest approach as well as it would require little or no mechanical changes.

Post by **Q45tech** » Thu Apr 24, 2003 7:33 am

So may the new standard of excellance is 76-77 lb/ft per liter.If you use direct injection you don't have to displace the 5-8% air volume with fuel. Most of that extra air can be directly applied to getting a higher BMEP......thus these direct injection engines are getting 80 even 81 lb/feet per liter with 11:1 CR.

The lastest NASCAR engines are exceeding 530 lb/ft at 7,000 rpms that's about 92 lb/ft per liter with 12.5 CR on racing gas.Indy Infiniti 35A ~~ 320 lb/ft at 10,400 rpm=91.5 lb/ft per liter with 13.8 CR on Methanol. The parts kit to assemble these engines is $89,000

80 lb/ft per liter is pretty strong in an engine designed for the street

Post by **VashFC** » Fri Oct 08, 2004 1:20 pm

Interesting topic. A lot of the drivers out there aren't even aware of how important torque really is. Hence the old adage from Caroll Shelby "Horsepower sells cars, Torque wins races". There's a member on sr20forum that claims 170 ft/lbs on their SR20VE. That figure might even be at the wheels! I hate to speculate however since they didn't say specifically, but all figure of horsepower were given in figures at the wheels, so I can only assume that would follow suit. I do emphasize claim since they have yet to post their dyno run. However, if it is true, that would net 85 ft/lbs per liter. Quite respectable.

- Chris

Post by **Q45tech** » Fri Oct 08, 2004 4:55 pm

SR20VE - 187hp @ 7000rpm / 145lb torque @ 6000rpmSR20VET - 276hp @ 6400rpm / 228lb torque @ 3200rpm

Stock 145/2= 72.5 per liter at 6,000 rpmA few of the posters are claiming 155/2=77.5 gross at the flywheel

New 2002 retuned SR20VE204ps (201hp) @ 7200rpm21.0kgm (151lb-ft) torque @5200rpm

Intake camLow lobe: 8.4mm lift @ 220 durationLow lobe center angle: 110degHigh lobe:10.7mm lift @ 264 durationHigh lobe center angle: 104deg

Exhaust camLow lobe: 6.6 mm lift @ 244 durationLow lobe center angle: 122degHigh lobe:10.34 mm lift @ 268 durationHigh lobe center angle: 114 deg

Post by **VashFC** » Fri Oct 08, 2004 8:16 pm

The post at the forum mentioned before refered to a tuned SR20VE. Most certainly not stock. It had the following modifications:

SR20VE-N1 TB, N1 cams,JWT cam gears,N1 retainers,N1 valve springs,SR16VE M/T ,Nismo radiator(w/cap),AEBS GEN1 HEADER,N1 intake manifold W/TB , cobra maf,3" exhaust w/N1(APEXi) muffler,Greddy MSS for cam switching

I consider it quite impressive for the relatively simple modifications done.

- Chris

Post by **Q45tech** » Sat Oct 09, 2004 2:00 am

Remember the 75 lb/ft per liter was for an emission legal engine that must meet specs. Just because a car meets simple local emission testing doesn't mean it meets the specs manufacturers have to submit data on to EPA.

Local specs are 150% of EPA requirements.

Chassis Dynos almost always [except acceleration corrected mustang units] read optimisic. Plus the friction losses [correction factor] are much lower at torque peak rpm than those used for HP peak rpm........yet everyone applies them across the board as if they were constant.

Suppose the flywheel to front wheel loses were 8% at 4,000 rpm and 12% at 6400 rpm on a FWD manual car.

The other comparison problem is 2 liters I4 vs 4-5 liters V8, the larger the engine the more friction losses..........the V configuration, now I6 of 3 liters are pretty translateable or flat 8 cylinders or radial aircraft designs.

Post by **VashFC** » Sat Oct 09, 2004 12:19 pm

Interesting point. I failed to think about the accelerated frictional losses because of the higher RPMs. Good call. Oh, and I never bother to think about emissions. Thanks for the insight.

- Chris

Post by **I Need $$$** » Tue Jan 18, 2005 8:03 pm

If you want to get into frictional losses I imagine that tthere would be a slight loss in the BMW I6's since they are slanted. Don't know what degree they are set at but I am sure there is some amount of friction added. Just my .02

Post by **Q45tech** » Wed Jan 19, 2005 4:42 am

Ring friction increases with circumference [bore diameter]........why there are optimum bore sizes such that when combined with stroke [to set rpm]

A 3 liter V6 is optimum as is a 2 liter I4 or a 4 liter V8 [obviously you can deviate a little with trade offs]..........but the 2.5 requires a friction adding balance shaft and for sure a 3.5>4.0 V6 is not a vibration free at high rpms.

http://www.superflow.com/suppo...d.htm

http://www.me.queensu.ca/courses/MECH435/ 2.%20Engine%20Performance.ppt

Post by **Calesta** » Wed Jan 19, 2005 10:02 am

Hey guys, I haven't been on NICO in a while, but I read through this thread and just wanted to add some fuel to the Honda engine fire. Here's my dyno sheet from last year:

The engine isn't really anything crazy- it's just an overbored B block (85.5mm) running an OEM crank and displacing 2044cc with 12.8:1 compression CP pistons. The head is 100% stock- that's why you see the rapid falloff in torque after 5500rpm. Specific torque is 78 ftlb/L here.

This is when I displaced only 2020cc and was running 12.4:1 compression (74.9ftlb/L):

And the first mildest build, just a B20 block (84.5mm bore, 1997cc) and VTEC head with all stock components except pistons (12.6:1) and rods (70.1ftlb/L)

One more- engine built by the guy who I buy my engine pieces from, (86mm bore, 2067cc) built all to hell (84.3ftlb/L)

All four are all motor, all running on pump gas. If a production manufacturer were willing to run compressions that high and tune this aggressively, 75ftlb/L would be easy to beat all the time. Of course, you have to tune down so people can screw up and put regular gas in their tanks, not maintain their engines, not change their oil blah blah blah... so this will never happen in a general consumer car.

Edit: all numbers were at the wheels, so factor your 15% driveline loss back in and you have even higher numbers. I believe the discussion was referencing crank torque numbers.

Post by **I Need $$$** » Thu Jan 20, 2005 6:42 pm

Those are some impressive numbers. What car was that in. Oh and I doubt that the engine is CARB legal. That is one of the impressive things about the Dinan package.

Post by **Calesta** » Sat Jan 22, 2005 11:09 am

I Need $$$ wrote:Those are some impressive numbers. What car was that in. Oh and I doubt that the engine is CARB legal. That is one of the impressive things about the Dinan package.

My engine builds were in a 95 Civic 4 door. I don't know what kind of car the last one was in, but I think it was in a lightweight 92-95 Civic hatchback.

You're right though- there's no way in hell that any of my engines are CARB legal. They might pass the sniffer, but the parts I used in the blocks won't pass a smog ref.

Dinan breaks the torque barrier

Re: Dinan breaks the torque barrier

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