gt2871 dyno
 

Put the car on the dyno today. It made 300.8hp 282.1 tq at 19psi. I'll post video and chart when i get home. I was too excited to wait to post. :giggle:

Pics or bans!

Can you post details on the bottom end? I see it has eagle rods. Does it still have stock pistons and fully stock 99 head?

GREAT NUMBERS!!

What specific 2871 do you have? What manifold are you using? What is your spark table? What type of dyno?

Yes please post spark table. That sounds kind of low.

Thats what I was thinking, but I don't know what intake and exhaust manifold. I have seen a 2560 on a perfect setup make 300hp at the same psi.

The bottom end just has eagle rods, stock '95 pistons and rings, 99 head is completely stock, stock intake manifold, BEGI cast exhaust manifold, GT2871 .64AR.

I've certainly seen better numbers from others on the same turbo, but I'm more than content.

Attachment 189121

Attachment 189122

The weird little midrange dip has me a bit concerned, I'm wondering if I'm past MBT since that was probably the most advanced are in my spark map compared to others I've seen. I'm going to pull a few degrees between 4900 and 5500. I'll post the spark map in a few min.

The low (red) line is what I daily, 285hp, 270tq

Did you get dyno tuned or just ran for hp numbers? Afrs look pretty shaky between 12.0 and 11.0. I bet there's more power on the table if you did more fuel tuning.

They were doing a dyno day so it was just a pull. I just installed new injectors not long ago and the fuel map definitely needs a little more loving. I'm sure there's a good bit left in it with a real tune.

Here's the video, pretty uneventful:



Here's the spark map I was using at the time of the dyno:

Attachment 189119

And I pulled a couple degrees... If someone has advise on this I'm certainly open to opinions, timing may not even be the issue, it was just the first thing that crossed my mind.

Attachment 189120

You run much more timing then me up top. I never realized how low I had mine set. I am going to try a similar timing map as yours up high and see how my built motor does.. I will try to get a log on my 2871 so we can compare.

????

Your 2300-3400 cells look pretty aggressive but hey if it's not knocking that's great.

Up top though, you are pretty far from MBT. I am at 22*@200kPa@7000RPM which is at least 4* short of MBT. My tune is safe because timing can ramp with engine speed because the piston is traveling faster and there's less time for fuel to burn.

I think that you have a lot left on the table.

Wow, that's a lot of timing up top, I'll definitely think about adding a little up there. They're dynoing until 10pm. I'm halfway thinking about messing with the map and going back out there. I really didn't like how power falls off up top, looks like there's another 10hp easily if it can hold the curve longer.

Are these uncorrected dyno dynamic numbers? Just curious our local dynamics reads %18 lower then a dynojet. Just to throw that out there for anyone comparing this plot to another turbos plot that's on a dynojet.

Not sure on the correction. I'm back out at the dyno with a few more degrees of timing up top, going to do another run. Will post later.

319hp, 292tq the 2nd time around. It was a good bit cooler, so tough to tell what the differences were until I can overlay the graphs. They were using a 1.1 correction factor, so numbers shouldn't be significantly lower than other dynos.

I just got back from trying out your conservative spark table on my 2871 and holy fucking shitballs I picked up a ton of top end power. Mind posting a log or screen shot of your car in the 1:1 gear?

Please post your updated spark table too. It's cool to see the tune and results in progress :)

Here's the dyno from the 2nd time around:

Attachment 189099

Ambient temps were probably 20 degrees cooler the 2nd run and humidity was way down as well which makes the number pretty much irrelevant.

Timing for the 2nd run:

Attachment 189100

I pulled a little timing from the midrange and added some up top for the 2nd run. That stupid midrange dip got worse but it held power better up top. After overlaying the dyno charts to look at the tq curve the first run looks better up to 5400 and the 2nd run was better above that. With those results the timing is going back to the original map in the 5200 and 4600 columns and staying the same above that.

Thanks for the advise guys, especially Fae, you definitely gained me a few hp.
:bowdown:

I like to think that I'm a pioneer of the poor mans dyno tune. :laugh:

Nice numbers.. I think the 2871 would be my turbo of choice if I ever decided to boost it.