HP???

[72240z]

Thats the exhaust your hearing more then anything. I love the muffler they used on the 350z/g35, sounds awesome. Using a conventional collector to single out with a vq yields the same sound and most other v6s though. Flip the coin and its the same thing, toss that muffler on a similar displacement v6 and it sounds just about the same. The muffler uses a somewhat unique baffle design that makes it sound so good. I had 2, one to cut open and look and one I was going to put on my 72. Sold the 72 so that didnt happen. 

I think in our datsun gross hp doesnt mean much. The power to weight ratio is whats important. 

Right now but soon to change I'm running a high comp l28 with triples, aggressive cam, full exhaust, electronic ignition, efan blah blah. Its bad ass but I would be lucky to break 200 rwhp with it. Which isnt that bad, 200hp in a 2200lb car is quick. Last fun run I kept up with a 370z flat out and he started walking me at the top of 2nd low 3rd. I can beat a 350z 0-100 by a hair. I hope see see a bigger improvement when I go itb and then way later maybe SC but the point is one doesnt need high hp in a light car lol.

Rear ratio doesnt change dyno results.  

skip to 7:50

[73DATSON]

A good condition stock l20b puts out 110hp. I'm not sure if that's at the rear wheels of a 620 or at the flywheel. 1000$ builds a fat

 

I'm looking at swapping for a KA24DE. I need more power for offroading.

My L20B not stock. Bottom is new with stock piston and crank, I wanted to put flattop but hear that's not a good ideal. I have a new U67 rebuild all new parts port polish new cam 287 lifters springs valve job cam gear header and MSD. Dualsidedrafts

[73DATSON]

If this car doesn't break the 125 mark after I'm done with it ill be a very unhappy RATSON:-(((

[Dawa]

the problem is, dynos are expensive (which conflicts with the ratsun way.)

i always hear and read a whole buncha numbers, but never see any dyno sheets (unless people are quoting those sheets)

[Dat Lurka]

I don't even know where to find a dyno... 

My truck will do 0-60 in 11 seconds downhill with a single barrel burning as much oil as gas. It will also comfortably haul 1000 lbs of scrap to the yard. Going on 228k  miles on the bottom end. 

[72240z]

It's easy to balls park a L series because they have been done to death for 40 years. One can find either their own set up or one very close that has been dynoed if they look well enough. There is a whole thread on hbz for N/A L6 combos and dyno results. 

[Dawa]

^ yeah i guess i didnt look at it that way. and 1/4 mile or 0-60 times are pretty helpful too

[ssnapz]

stock napz24, mild cam, 350cfm holley, home made header, 8mm wires, guessing 150 @ the flywheel. planing a turbo and possible r1 carbs. want to get it on the dyno before anymore upgrades though[/quote

 

Nice. R1crabs y? R they better to use?

they will be cheaper to use with turbo, and i like the look of a carb per cyl. if i could afford it i would do 4 tiny turbos just for the look.

[72240z]

Cheaper then what? I think a single SU suck though is cheaper, easier and more straight forward then a 4 carb blow through.

Def doesnt look as good.

  
There was a car at SEMA a few years ago that did I believe 8 with a v8

[73DATSON]

Cheaper then what? I think a single SU suck though is cheaper, easier and more straight forward then a 4 carb blow through.

 

Def doesnt look as good.

 

 

There was a car at SEMA a few years ago that did I believe 8 with a v8

OMG!!!! I've die and gone to HELL!!!! That looks crazy:-))))

[73DATSON]

Well as soon as I get all my stuff in and get it in the car, tune it up ill be at the dyno:-)) ill post the sheet up too and ill be taking a video of it to.

[73DATSON]

Thats the exhaust your hearing more then anything. I love the muffler they used on the 350z/g35, sounds awesome. Using a conventional collector to single out with a vq yields the same sound and most other v6s though. Flip the coin and its the same thing, toss that muffler on a similar displacement v6 and it sounds just about the same. The muffler uses a somewhat unique baffle design that makes it sound so good. I had 2, one to cut open and look and one I was going to put on my 72. Sold the 72 so that didnt happen.

 

I think in our datsun gross hp doesnt mean much. The power to weight ratio is whats important.

 

Right now but soon to change I'm running a high comp l28 with triples, aggressive cam, full exhaust, electronic ignition, efan blah blah. Its bad ass but I would be lucky to break 200 rwhp with it. Which isnt that bad, 200hp in a 2200lb car is quick. Last fun run I kept up with a 370z flat out and he started walking me at the top of 2nd low 3rd. I can beat a 350z 0-100 by a hair. I hope see see a bigger improvement when I go itb and then way later maybe SC but the point is one doesnt need high hp in a light car lol.

 

Rear ratio doesnt change dyno results.

 

skip to 7:50

Great vid man. Can't wait to run with u guys....

[ssnapz]

cheaper then doing a blow through on my holley, and suck through doesnt give enough power to make it worth the work or money

[ssnapz]

@ dat510 is lmc using the dyno yet, i wanna get my truck on it

[datzenmike]

A good condition stock l20b puts out 110hp. I'm not sure if that's at the rear wheels of a 620 or at the flywheel. 1000$ builds a fat l20b. 

 

Around 90 RWhp. Under ideal conditions and brand new stock broken in motor. If yours is 85,000 miles it won't be that high.

 

Rear ratio doesnt change dyno results.  

 

But isn't the RWHP calculated by how fast the RPMs change over time? Running a 3.70 axle and then changing to a 4.375 with no other change would trick the dyno because the RPMs would rise faster. The dyno would 'think' that the motor is making more power to accelerate faster.

 

I do see that a dyno shop could dial in the rear axle ratio to keep comparisons between two cars similar.

 

If everyone had their car on a dyno there'd be a lot of crying tonight. Spend 200 on a header, replace the plug wires and put a superdooper whiz-bang thunderbolt tornado earthquake lightning coil on it and K&N air filter and get 89.5 hp????? WTF is wrong with that dyno? I spent $300 to go sideways???

[73DATSON]

Ok now DATTO guys let keep getting in those HP # of your ratsun. Don't want this write up to be all brain and no muscle:-() where my L motor?

[ggzilla]

4 pages and not a single dyno sheet? The only figure here that sounds realistic is the 70 hp. Why do you want guess-at HP numbers? I predict your L28 with triple carbs will on be 150 RWHP.

 

Factories ALL use at the flywheel measurements and SAE-specced brake dynos. That 105 HP for an L20B and 154 HP for a KA24DE

 

Aftermarket Dynos are Rear Wheel HP, and one-off calibrated so they are not very accurate. The drivetrain affects the power including tranmission gear losses and final gear losses, but not the final gear ratio, if measured correctly. This is why RWHP is always considerably less than OEM HP. Probably 85 Hp for an L20B and 125 HP for a KA24DE.

 

 

That being said, here's the Datsun A12 1.2 liter engine:

 

OEM Flywheel 69 HP:

 

RWHP of same engine before and after tuning:

[72240z]

Around 90 RWhp. Under ideal conditions and brand new stock broken in motor. If yours is 85,000 miles it won't be that high.

 

 

But isn't the RWHP calculated by how fast the RPMs change over time? Running a 3.70 axle and then changing to a 4.375 with no other change would trick the dyno because the RPMs would rise faster. The dyno would 'think' that the motor is making more power to accelerate faster.

 

I do see that a dyno shop could dial in the rear axle ratio to keep comparisons between two cars similar.

 

hp is a function of torque, so it does matter but not much imho.

 

Ya thats the point though it should be dialed in on a modern dyno. In which case they are close if not the same. Dynoing a car with no set up then changing the rear and doing it again is going to change it but only slightly. I read somewhere on hbz but cant find the difference between 3.7 and 4.11 was 10hp/tq lost with the higher gears. Seems negligible to me but I guess not all lol. You get a different result doing runs in different gears which why I think so. Even dynos are just a ball park all said and done. 

[72240z]

cheaper then doing a blow through on my holley, and suck through doesnt give enough power to make it worth the work or money

 

Ya, only the topic was draw through verse blow though. Generally draw through is way easier all round and cheaper then blow through as I said. With comparable power as well. 

 

I wouldnt blow through a holley either lol.

 

Doesnt get much easier or cheaper or straight forward then this

[datzenmike]

 

Byron's sheet. Thrown together LZ22, home made ITB EFI, mystery cam and springs. The year previous was with side drafts and was only 6hp lower.

 

I read somewhere on hbz but cant find the difference between 3.7 and 4.11 was 10hp/tq lost with the higher gears. Seems negligible to me but I guess not all lol. You get a different result doing runs in different gears which why I think so. Even dynos are just a ball park all said and done.

I mention this because a dyno tune can show an increase on a sheet to a customer if they 'slip it into 3rd' without him knowing. 10 RWHP (even on paper)is a big deal to some kids.

[ggzilla]

1/4 MPH is a more accurate indicator of HP than than a RWHP dyno. So post your 0-100 times, 0-60 times or 1/4 mph.

 

My stock A12 put out more HP than the rwhp dyno'd A12 above.

 

My 1200 did 65.0 mph in the quarter consisently. That's 62 HP (48 rwhp) for a 1900 lb laden car (1640 lb, 190 lb driver, 60 lbs tools, parts, gasoline).

 

62 hp (48 rwhp)

[datzenmike]

Two things:

 

1/ Talk is cheap

2/ The ass dyno adds 23%

[72240z]

 

Byron's sheet. Thrown together LZ22, home made ITB EFI, mystery cam and springs. The year previous was with side drafts and was only 6hp lower.

 

 

I mention this because a dyno tune can show an increase on a sheet to a customer if they 'slip it into 3rd' without him knowing. 10 RWHP (even on paper)is a big deal to some kids.

 

 

Thats a pretty good dyno imo

 

Ya I guess it is a lot to some. I dont think they realize there is more then that amount of inaccuracy built right into a dyno lol. 

 

Dont forget stickers either Mike. Stickers add 10%

[72240z]

I agree that a good 1/4 is a better calculation. Anyone ever use a gtech? My old TT z32 dynod and gteched (calc by running a 1/4) within 20hp of one another. the G tech was closest to stock figures. I was pretty impressed that something that plugs into a lighter would be that accurate, or that the dyno would be so inaccurate? lol 

[73DATSON]

4 pages and not a single dyno sheet? The only figure here that sounds realistic is the 70 hp. Why do you want guess-at HP numbers? I predict your L28 with triple carbs will on be 150 RWHP.

 

Factories ALL use at the flywheel measurements and SAE-specced brake dynos. That 105 HP for an L20B and 154 HP for a KA24DE

 

Aftermarket Dynos are Rear Wheel HP, and one-off calibrated so they are not very accurate. The drivetrain affects the power including tranmission gear losses and final gear losses, but not the final gear ratio, if measured correctly. This is why RWHP is always considerably less than OEM HP. Probably 85 Hp for an L20B and 125 HP for a KA24DE.

 

 

That being said, here's the Datsun A12 1.2 liter engine:

 

OEM Flywheel 69 HP:

 

RWHP of same engine before and after tuning:

I will hang it up if I get numbers like that!!!!!:-(((