Standard L28 Power Figures

[Toecutter]

Has anybody got some dyno figures on a standard L28 with stock cam. I'm just curious at what rpm the power drop off at? Please feel free to comment just based on driving your L28 and were it feels as though is the upper limit of producing any more power?

Sulio

[PZG302]

With mine on injectionand a 76 degree cam the power falls away at about 65-6600 rpm. I use a max of 6800 by the tacho, probably about 7200. That's where the motor changes note to the horrible scream that says go up a gear.

[Zedman240]

My previous 260 with my current EFI setup and bog stock L28 made 108Kw at the wheels. Have to dig around to find the dyno sheet!

[Toecutter]

Thanks guys. Demitri I meant more in terms of power limit in respect to revs as I'm  getting good power all the way through until hits 5000 where the engine will rev but no more significant power gains. I've got pretty small (130) main jets so I think going bigger main jets (145) will get me that more power to the 6000rpm ish range. Anyhow just wanted to see what a stocky will do on SU's as I can't recall what it was like on the SU's?

I'm hoping to have my AFR gauge sorted and O2 sensor installed this weekend to check on mixtures through out entire rev range and make sure I don't over jet it in my quest for more power!

Sulio

[Zedman240]

sorry, forgot to say I never really gave that engine a good rev. From memory, after about 5500 - 6000 it was painfully obvious power had fallen off. Good strong torque from around 3k to about 5ish. The triples do so much! With the efi, there was no jetting to worry about so the power figures I was getting I think was as much as you could get from a stock L28. Also my TB's are equivalent to 50mm Webers.

[Toecutter]

Good strong torque from around 3k to about 5ish

ah well this is where I'm at, might be due to the cam re the peak power. Will keep tinkering.

Thanks Again,
Sulio

[PZG302]

They're the revs I would expect for a stock cam, good torque and power from 3-5. A bigger cam will raise the revs at which the power drops off, but then your torque curve gets peakier and comes in higher. A good torquey motor will always blow away a peaky motor in the real world.

[Toecutter]

They're the revs I would expect for a stock cam, good torque and power from 3-5. A bigger cam will raise the revs at which the power drops off, but then your torque curve gets peakier and comes in higher. A good torquey motor will always blow away a peaky motor in the real world.

My plan is to go to a mild cam at a later stage. An increase and shift in the power curve by 500 or 1000 rpm would still be ok as it drives very good down low at the moment which works pretty good with stock ratios and 280 box.

I won't do anything further re jetting until I get some AFR figures hopefully this weekend but I reckon my main jet will most likely be a little undersized so if thats the case maybe I'll be able to squeeze a little bit more out at the top.

Sulio

[modular9]

PZG302 : nice concise info there  .

Was looking at a mid range cam from tighe cams up here in bris ( 312 or 812c on here http://www.tighecams.com.au/profiles3/nissanlseries.htm  ) But at present using a l24 cam in the l28 I am building.

[260Coupe]

Guys

If you are after a fresh cam give Camtech a call or check out their site
http://www.camtechcams.com.au/........ they have billets in stock (not reground standard cams). So they fit with no modification to lash pad heights or rocker wipe (if your head still standard.
Tighe in QLD are out of stock of L6 cam billets and they are on back order (as with Wades etc)

Sulio
the only accurate method to assess mixture and power/performance is to run the car on the chassis dyno.

You can get very reasonable dyno tuning rates (half the price of Power Play) with proven results from Lou Mondello in Moorabbin (9555 9591).
The last Zed he did (L28 with triple dellortos "expertly" set up by the Zshop.....pwfft!) went in making less than 90 rwkw and came out with 120+ rwkw after some carefull mixture and cam and ignition timing adjustments...........needless to say the owner was stoked !!   


cheers
Alan

[Toecutter]

Hi Alan,

My plan is to rebuild this engine when my house extension/garage is finished and this is the reason I have been holding out re dyno tuning. As a result I have been learning alot on how the car is running re the carbs I've installed and continue to do so. The AFM reader I'll install next week will also be part of that learning curve.

Once I finish the rebuild yes then it will be a good idea to have it properly tuned but even then it will only be once I've thoroughly given it my all as far as research and my own adjustments go. Only at that point will it be very interesting to get it on a rolling road and tune it.

In the mean time it would be a good idea to have a dyno day for some of the Z guys here. I'm just waiting on Ash to get me some numbers on price based on numbers attending but that another thread that is currently active on this forum.

It would be nice to get 160HP at the wheels with current set up, I really need to jump in a Z thats doing about 200HP at the wheels to get some benchmark feeling.

Sulio

EDIT: Alan, did you get the dyno sheet since your rebuild? I did your informative thread re your rebuild, it sounds like you got exactly what you wanted re your cam selection, will be looking at same supplier when that time comes.

[modular9]

...
It would be nice to get 160HP at the wheels with current set up, I really need to jump in a Z thats doing about 200HP at the wheels to get some benchmark feeling.
...

Dont we all !! Purely for that benchmark feeling ...   

What AFM monitoring doodad did you go for ?

[Toecutter]

Well I'm not sure if 160rwhp is being unrealistic based on the current set up, L28 with elec dizzy, headers and 40mm tripples but that why I'm posting this thread.

As far as the AFR meter goes I bought an LSM-11 aftermarket Bosch O2 sensor and waiting for gauge from Jaycar:

http://www.techedge.com.au/vehicle/wbo2/5300.htm

Sulio

[modular9]

dont we all :  regarding sitting in a 200 hp datsun for "benchmarking" not your power goal which you should get close to.

Hell if my stocko l24 with piston blowby and valve leakage  can do 105hp on triples and stock exhaust... you'll get close to your goal methinks.

Thanks for the link to the AFM.

[Toecutter]

oh yes I see Modular, yer I don't think 160HP is too unrealistic from what I've read but another thing that starting to look clearer is stock L28 cam might actually peak at about 5000rpm so my current set up might well be limited by the cam but as i said will push on next week.

EDIT:

after reading the post below I think my figure of 160 at the wheels is unrealistic with the current motor set up. 140 would be more realistic.

http://forums.hybridz.org/showthread.php?t=92888&highlight=l28+curve

Sulio