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Thread: Went to the dyno last night, tell me what you think

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Posts: 191-200 of 210
2008-10-21 04:24:35
#191
Originally Posted by 5speed
I want say good job to everybody that participated on dyno day.

After looking at the dyno day video. I'm surprise no one has mentioned or noticed the peak power rpm on the cars. They are optimistic by at least 500 rpm. Here’s a comparison.

New Zealand:

N1 cams peak at 8,500
20V 8,000
20V Wagon 8,500
Stage 4 8,500 to 9,000
SR16 7,500
Stock cams 7,500

US:

N1 7,500
20V 7,200
Stage 4 7,800 flattening to 8,500
SR16 7,300
Stock 7,000

I suspect the New Zealand dyno graphs is off on the rpm grid. It would also explain why the New Zealand cars need to activate so high up on the rpm. In actually, the rpm graph is optimistic.


It's difficult to gauge what the exact RPMs are, off the graph, as they add that in after the run (i.e. asking the owner where their rev limit is).
I know what mine was, as I set it in the program, and they adjusted the graph around that; after the run.
I also know that my car does pull easily to that figure stated on the road, it's got a 4.411:1 final drive, which does help.
I can't say for the rest of the cars but mine does feel about right, I'm only going on SOTP here though; and we ALL know how accurate that is...
2008-10-21 05:37:03
#192
Hi Mom!
2008-10-21 05:42:41
#193
Originally Posted by SERacer
Originally Posted by Clint

Kelford's 184-C made exactly 1kw less than the N1 at dyno day and stopped making power at 7,300rpm. I have to work out why as they are supposed to make power to 9,000rpm. Picking it could be either exhaust or cam timing.


Question ? Did these cams come with cam specs? Degree card? Good cam manufacturers always have the spec. with their cams. Were these cams degreed to these specs? Post up the spec card, please.

Just a thought.


Aaah... I knew somebody had asked if I had a degree card!

These are a new grind and I did get a spec card (which I can't find right now) but the engine was rebuilt and assembled by Cook Motor Racing who are probably our foremost expert on the VE. Reg Cook & Kevin Ban from Kelford have worked together for years so dealt directly with each other in setting up the cams and I just left them to it. Reg has some other ideas for the cam timing which I hope to try later. I think you can find the specs on Kelford's website.
2008-10-21 07:09:28
#194
my n1's peaked at ~7100rpm and started dropping off at 7500rpm


I expect this is due to the 2.25" rear section of exhaust holding back the top end, but I still have to play with cam timing
2008-10-21 10:13:55
#195
Adrian does have head work to his N1 engine though, so that would shift the power band upwards. Also my Stage 4's had dropped power by 8000rpm, more so because of my exhaust than the cams.

From what I've watched from cars on the dyno, those RPM figures are pretty accurate, however, would the fact that this particular dyno is a rolling road have any significant effect on readings?
2008-10-21 10:21:21
#196
My N1 cams peak at 7800. I think the peak and how long the car holds the power has more to do with header length, exhaust size and shorter runner intake manifolds.

If you take a look at Corys Dyno of 212 WHP his power band peaks late and holds for a long time. He is also 3 inch exhaust but with a 2 in or so shorter intake manifold than mine
2008-10-21 10:35:07
#197
agreed, the intake and exhaust systems will play a larger part in enabling the motor to breathe after passing the peak airflow of the cams.
Really must sort out my exhaust, i'd like to hold peak power to redline rather than drop off in the last 1000rpm.
2008-10-21 10:42:29
#198
Its always good to look at the competition to see what they are doing. I have seen a few of these motors taken apart, I have also seen comparable intake runners from the older model K20s to the newer models K20s here in the USA and one thing that stand out is alot of the K20A guys run the stock intake manifold. There are 2 diffrent intake manifold that look the same from the outside but the runners are way bigger on the inside. I dont think they are shorter so if someone knows they can add in.

Now, there is a company that makes a real nice intake manifold and they are called IPS but if I am correct this is the only intake manifold that truely outperforms the factory upgraded unit that comes on the Type R units.

You will see many a large HP K20 or K24 running the factory upgraded intake manifold.


2008-10-31 07:24:51
#199
I guess its about time i got back on here, had some pretty major issues complicating my life.

My opinion of the 20v/N1 cams is they work well in the 20v engine, with 20v headers. Really to test these cams properly, they need to be fitted to a p11 engine to see if they make similar torque, or if it is indeed just the p12 engine that is a better design and makes good torque. There is a p11 engine with 20v cams, but it has issues and doesnt run properly.

At this stage, im selling up everything, i may keep the chassis as i dont think i could sell it for anything but scrap steel, and will prob put the 6 speed box in the corner for the future, but i dont have the will to continue with the VE engine, and will prob build another turbo engine in the future (like 3 to 5 years)

Cheers for the interest in the thread, i'll be gutting the car and taking to drags next friday for one last blast, then the engine is coming out, hopefully for someone else in the NZ comunity to continue developement.
2008-10-31 07:28:31
#200
^^^ wow that was sudden

hope everything works out for ya buddy
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