SU's Dyno, triples Dyno

[grannyknot]

A moderately built L28 with well tuned ZTherapy SU's,

Had this done last week on a Dyno Dynamics machine, torque appears to be 190-192 ftlbs

I'm pretty happy with those numbers, but now I have installed a set of SK/OER triples and once I have those tweaked to best performance I'm heading back to the same dyno to answer for myself which carbs are better for me. I don't want to reignite that debate again but I thought some might be interested in the results so I'l post them as soon as I get them.

I am really loving the triples, great sound and the car feels stronger but I could just be fooling myself.

Chris

[240260280z]

Good stuff.

[Patcon]

I assume that HP number is at the wheels...?

C

[grannyknot]

I assume that HP number is at the wheels...?

C

yes it is

[Travel'n Man]

I still have my Hitachi's but doubt I will ever put them back on - should be interesting. What is the bulletpoints of your engine set up other than the L28 - what head and block, cam, so forth?

[madkaw]

Chris,

please elaborate on the engine. We have so few dyno numbers posted here, it would be great for reference. Please be specific as to all aspects,-- timing, cam , head, exhaust, etc...

Looks like good numbers. Did you not want to take it past 6000rpm?

I'll be next soon with my double-triple numbers.

[grannyknot]

F54 block, N42 head, port and polish, port matched,

Crane mild cam grind on a Nissan blank cam,

Flat top pistons, not sure which ones,

Cylinder bored 0.020" over, 10:1 compression,

10 lb aluminum flywheel

Steve, didn't want to go over 6000 rpm cause there was some ping happening which has disappeared with the triples.

[Patcon]

I thought those were very reasonable numbers too for a moderate build. I would think you will put down some more power on the triples because they should tend to be a little richer and power requires fuel... the pinging would indicate that too.

Charles

[LeonV]

I thought those were very reasonable numbers too for a moderate build. I would think you will put down some more power on the triples because they should tend to be a little richer and power requires fuel... the pinging would indicate that too.

Charles

?

Sorry, but your post makes no sense. Put simply, triples make more power because they decrease pumping losses on the intake side and distribute the mixture more evenly amongst the cylinders (individual runners). They also generate a stronger resonance effect because of those individual runners.

Regardless, sounds like a healthy engine, granny!

Edited September 12, 2013 by LeonV

[grannyknot]

I forgot to mention that I'm not using a header, I took a stock cast iron exhaust manifold and hogged it out to match the larger exhaust ports and smoothed the interior a bit, I would love to polish the interior of the manifold just not sure how I would do that.

[madkaw]

Those are better than reasonable numbers- those are excellent numbers. I have read too many threads where folks have gone the stroker route and didn't do this good. Looking like 200+ HP at the rear wheels with triples is very possible . That is an accomplishment to be proud of- congrats.

Where were you at with the timing and what ignition ?

[Patcon]

Leon,

The thought was along the lines of pinging is a lean condition so more fuel eliminates pinging and gets a mixture ratio more in an acceleration range or 12.5-13.5. The larger displacement of the 2.8 requires more air which is easier to accomplish thru three dcoe type carbs than two single bore carbs without raising velocities a lot higher. It seems triples tend to run some what rich and at the DCOE Yahoo group that is the way they suggest running them. Lastly gasoline is being converted to power, so to make a lot of power it takes more fuel. That is why even new cars with crazy amounts of power with modern systems don't get fabulous fuel mileage because the engine needs a certain amount of fuel. Just my deductions...

Charles