Highest torque in a 1.8L engine? - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


General Miata Chat A place to talk about anything Miata

Reply
 
 
 
LinkBack Thread Tools
Old 06-17-2008, 11:17 PM   #1
Elite Member
Thread Starter
iTrader: (22)
 
Join Date: Dec 2006
Location: Sunny Spanish speaking Non US Caribbean
Posts: 3,257
Total Cats: 3
Default Highest torque in a 1.8L engine?

Like the title says; silly question: where in the 1.8L engine's RPM band does one see the highest torque?

Thanks
Rafa is offline   Reply With Quote
Old 06-17-2008, 11:21 PM   #2
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,147
Total Cats: 6
Default

I don't know off hand. IIRC it's 4500 rpm, might be 4800 though. It also has to do with your spark tuning Rafa. If your spark map is garbage your torque might peak earlier then that and then drop drastically to redline.
cjernigan is offline   Reply With Quote
Old 06-17-2008, 11:55 PM   #3
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,038
Total Cats: 407
Default

Stock 2001 on a dynojet. 4400-4800 is the max but it's pretty flat. and you know you love the 100 ft lbs from 2200 rpm.

y8s is offline   Reply With Quote
Old 06-18-2008, 12:12 AM   #4
Senior Member
iTrader: (7)
 
Join Date: Aug 2007
Location: Southern Indiana
Posts: 1,371
Total Cats: -1
Default

Name:  100_0655.jpg
Views: 2
Size:  84.8 KB
wes65 is offline   Reply With Quote
Old 06-18-2008, 08:27 AM   #5
Elite Member
Thread Starter
iTrader: (22)
 
Join Date: Dec 2006
Location: Sunny Spanish speaking Non US Caribbean
Posts: 3,257
Total Cats: 3
Default

Quote:
Originally Posted by cjernigan View Post
I don't know off hand. IIRC it's 4500 rpm, might be 4800 though. It also has to do with your spark tuning Rafa. If your spark map is garbage your torque might peak earlier then that and then drop drastically to redline.
I'm trying to retard a little timing in the peak torque band to avoid issues.

BTW, thanks for the info guys!
Rafa is offline   Reply With Quote
Old 06-18-2008, 12:11 PM   #6
Elite Member
Thread Starter
iTrader: (22)
 
Join Date: Dec 2006
Location: Sunny Spanish speaking Non US Caribbean
Posts: 3,257
Total Cats: 3
Default

Another dumb question....

This is a quote from the AEM EFI Basics manual:

" Spark plug selection affects engine performance. On forced induction engines, it is critical that the proper heat range and gap is used. Heat range refers to the ability of the spark plug to conduct heat away from the electrode to the engine. A plug that has high thermal conductivity has a short insulator that comes in contact with a large portion of the metallic plug shell. This large area allows the combustion heat to be carried through the plug shell to the cooling jacket of the cylinder head. In the case of a hot plug, the insulator is recessed deeply into the plug shell with minimal contact to the shell. The plug has low thermal conductivity due to the lack of contact with the shell. The nose of the insulator should operate at between 400 – 850 degrees C. Temperatures above 400 degrees C are desirable because at higher temperatures deposits from carbon, lead or soot are burnt off. Temperatures of 850 degrees C and over should not be exceeded because this is typically the point where detonation or auto ignition can occur. Lower heat range plugs have a higher resistance to auto ignition while higher heat range plugs have less tendency to foul."

So, my question is: everyone talks about EGTs; is there any simple way to know what are the temps at the spark plugs?

Thanks
Rafa is offline   Reply With Quote
Old 06-18-2008, 03:37 PM   #7
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,038
Total Cats: 407
Default

Quote:
Originally Posted by Rafa View Post
Another dumb question....

This is a quote from the AEM EFI Basics manual:

" Spark plug selection affects engine performance. On forced induction engines, it is critical that the proper heat range and gap is used. Heat range refers to the ability of the spark plug to conduct heat away from the electrode to the engine. A plug that has high thermal conductivity has a short insulator that comes in contact with a large portion of the metallic plug shell. This large area allows the combustion heat to be carried through the plug shell to the cooling jacket of the cylinder head. In the case of a hot plug, the insulator is recessed deeply into the plug shell with minimal contact to the shell. The plug has low thermal conductivity due to the lack of contact with the shell. The nose of the insulator should operate at between 400 850 degrees C. Temperatures above 400 degrees C are desirable because at higher temperatures deposits from carbon, lead or soot are burnt off. Temperatures of 850 degrees C and over should not be exceeded because this is typically the point where detonation or auto ignition can occur. Lower heat range plugs have a higher resistance to auto ignition while higher heat range plugs have less tendency to foul."

So, my question is: everyone talks about EGTs; is there any simple way to know what are the temps at the spark plugs?

Thanks
not exactly but yes...

you can take them out and read them. generally though, you want to run the coldest plugs you can without them fouling. or the hottest plugs without risking detonation. or half way between?

y8s is offline   Reply With Quote
Old 06-18-2008, 04:14 PM   #8
Ben
Supporting Vendor
iTrader: (33)
 
Ben's Avatar
 
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,689
Total Cats: 99
Default

I run the stock spec plugs at a big *** gap, and they look just like the top left picture in [email protected]'s chart.

I believe that you should run the hottest plug that doesn't detonate. However, if you're a crappy tuner, paranoid, or if you're on track for long periods, you should go a little colder to err on the side of caution.

An overly cold plug will only foul up, give less than possible economy and power. An overly hot plug could cause you to loose your motor.
Ben is offline   Reply With Quote
Old 06-18-2008, 04:40 PM   #9
Elite Member
Thread Starter
iTrader: (22)
 
Join Date: Dec 2006
Location: Sunny Spanish speaking Non US Caribbean
Posts: 3,257
Total Cats: 3
Default

So there's no sensor available that will allow anyone to get feedback on the plugs' temp? I'm thinking that if I could keep an eye on my plugs' temp at all times I could prevent knock much easier than by reading EGT; I'm I wrong?

And about the gap; I'm a little confused Ben because the AEM manual states that in modern fuel injected, turbo engines one should keep the gap around 22 and you guys all run a much wider gap.
Rafa is offline   Reply With Quote
Old 06-18-2008, 04:42 PM   #10
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,114
Total Cats: 351
Default

the guys who run COPS can run a bunch of plug gap because they are men, and we are their bitches.
hustler is offline   Reply With Quote
Old 06-18-2008, 04:50 PM   #11
Elite Member
Thread Starter
iTrader: (22)
 
Join Date: Dec 2006
Location: Sunny Spanish speaking Non US Caribbean
Posts: 3,257
Total Cats: 3
Default

Quote:
Originally Posted by hustler View Post
the guys who run COPS can run a bunch of plug gap because they are men, and we are their bitches.
Do you mean you're my bitch now?
Rafa is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 58 12-13-2017 10:04 PM
WTB MP62 (Hotside) (NB2) Rick02R WTB 3 01-03-2016 08:18 PM
Changing from 460cc to flow force 610cc in diypnp 90 Turbo MEGAsquirt 19 10-19-2015 04:23 PM
Expected intake temps on the track? tazswing Race Prep 20 10-03-2015 12:04 PM
Recommended Tire Temp for best friction thumpetto007 Race Prep 4 09-27-2015 06:16 PM


Thread Tools

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 08:23 AM.