gt2871 dyno - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 05-07-2011, 01:13 PM   #1
Elite Member
Thread Starter
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default 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.
pdexta is offline   Reply With Quote
Old 05-07-2011, 01:14 PM   #2
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,860
Total Cats: 1,788
Default

Pics or bans!
Braineack is offline   Reply With Quote
Old 05-07-2011, 01:15 PM   #3
Senior Member
iTrader: (6)
 
Join Date: May 2009
Location: San Francisco
Posts: 989
Total Cats: 23
Default

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!!
wittyworks is offline   Reply With Quote
Old 05-07-2011, 02:00 PM   #4
mkturbo.com
iTrader: (24)
 
shuiend's Avatar
 
Join Date: May 2006
Location: Charleston SC
Posts: 13,775
Total Cats: 1,106
Default

What specific 2871 do you have? What manifold are you using? What is your spark table? What type of dyno?
shuiend is offline   Reply With Quote
Old 05-07-2011, 02:41 PM   #5
Elite Member
iTrader: (2)
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,782
Total Cats: 119
Default



Yes please post spark table. That sounds kind of low.
Faeflora is offline   Reply With Quote
Old 05-07-2011, 03:02 PM   #6
mkturbo.com
iTrader: (24)
 
shuiend's Avatar
 
Join Date: May 2006
Location: Charleston SC
Posts: 13,775
Total Cats: 1,106
Default

Quote:
Originally Posted by Faeflora View Post

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.
shuiend is offline   Reply With Quote
Old 05-07-2011, 03:35 PM   #7
Elite Member
Thread Starter
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

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.

Name:  100_1837.jpg
Views: 97
Size:  78.4 KB

Name:  100_1839.jpg
Views: 146
Size:  95.6 KB

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

Last edited by pdexta; 05-07-2011 at 04:04 PM.
pdexta is offline   Reply With Quote
Old 05-07-2011, 03:45 PM   #8
Senior Member
iTrader: (6)
 
Join Date: May 2009
Location: San Francisco
Posts: 989
Total Cats: 23
Default

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.
wittyworks is offline   Reply With Quote
Old 05-07-2011, 03:53 PM   #9
Elite Member
Thread Starter
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

Quote:
Originally Posted by wittyworks View Post
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.
pdexta is offline   Reply With Quote
Old 05-07-2011, 03:55 PM   #10
Elite Member
Thread Starter
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

Here's the video, pretty uneventful:



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

Name:  map1.jpg
Views: 86
Size:  56.9 KB

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.

Name:  mapnew.jpg
Views: 88
Size:  56.1 KB
pdexta is offline   Reply With Quote
Old 05-07-2011, 04:23 PM   #11
mkturbo.com
iTrader: (24)
 
shuiend's Avatar
 
Join Date: May 2006
Location: Charleston SC
Posts: 13,775
Total Cats: 1,106
Default

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.
shuiend is offline   Reply With Quote
Old 05-07-2011, 06:57 PM   #12
Elite Member
iTrader: (2)
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,782
Total Cats: 119
Default

????

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*@[email protected] 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.
Faeflora is offline   Reply With Quote
Old 05-07-2011, 07:14 PM   #13
Elite Member
Thread Starter
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

Quote:
Originally Posted by Faeflora View Post
Up top though, you are pretty far from MBT. I am at 22*@[email protected] 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.
pdexta is offline   Reply With Quote
Old 05-07-2011, 11:12 PM   #14
Junior Member
iTrader: (1)
 
Join Date: Jul 2010
Location: Louisville, KY
Posts: 196
Total Cats: 0
Default

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.
PatrickB is offline   Reply With Quote
Old 05-07-2011, 11:32 PM   #15
Elite Member
Thread Starter
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

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.
pdexta is offline   Reply With Quote
Old 05-08-2011, 12:55 AM   #16
Elite Member
Thread Starter
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

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.
pdexta is offline   Reply With Quote
Old 05-08-2011, 01:13 AM   #17
mkturbo.com
iTrader: (24)
 
shuiend's Avatar
 
Join Date: May 2006
Location: Charleston SC
Posts: 13,775
Total Cats: 1,106
Default

I just got back from trying out your conservative spark table on my 2871 and holy ******* 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?
shuiend is offline   Reply With Quote
Old 05-08-2011, 02:26 AM   #18
Elite Member
iTrader: (2)
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,782
Total Cats: 119
Default

Quote:
Originally Posted by pdexta View Post
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.
Please post your updated spark table too. It's cool to see the tune and results in progress
Faeflora is offline   Reply With Quote
Old 05-08-2011, 02:29 PM   #19
Elite Member
Thread Starter
iTrader: (17)
 
Join Date: Aug 2007
Location: Fort Myers, FL
Posts: 2,791
Total Cats: 130
Default

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

Name:  100_1841.jpg
Views: 171
Size:  103.5 KB

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:

Name:  revised1.jpg
Views: 87
Size:  56.0 KB

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.


I like to think that I'm a pioneer of the poor mans dyno tune.
pdexta is offline   Reply With Quote
Old 05-08-2011, 03:06 PM   #20
Elite Member
iTrader: (5)
 
Join Date: Oct 2007
Location: Canton, Ga
Posts: 1,707
Total Cats: 19
Default

Nice numbers.. I think the 2871 would be my turbo of choice if I ever decided to boost it.
Stealth97 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Turbo 1995 Miata Low mileage Clean Tekel Cars for sale/trade 29 02-05-2016 05:16 PM
Why dynos should plot Torque divided by MAP JasonC SBB ECUs and Tuning 11 10-27-2015 05:56 PM
Time to start learning and play with tuning The Gleas MEGAsquirt 3 10-01-2015 10:30 AM
1.8, C30-74 Rotrex, 9psi, 235WHP/190WTQ (E85) Lincoln Logs Dynos and timesheets 4 09-23-2015 01:26 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:52 AM.