Bought Novitec 156 turbo - Spark plugs? - Alfa Romeo Forum
You are currently unregistered, register for more features.    
Tuning & Upgrades Discuss performance enhancements for your Alfa Romeo

 
Thread Tools
(Post Link) post #1 of 18 Old 20-01-14 Thread Starter
Status: -
AO Member
 
deeznuts's Avatar
 
Join Date: Mar 2007
Location: Denmark
County: Arhus
Posts: 53

Member car:

159 Ti 2.4

Hmmm Bought Novitec 156 turbo - Spark plugs?

I just bought a 156 novitec turbo 2.0 TS and want to change the large spark plugs and MAF to see if that will free up some more power. The car feels to hold back a bit, and sometimes has small misfires when cruising.

Should i buy stock plugs and MAF, or do i need colder plugs and different type MAF?
deeznuts is offline  
Sponsored Links
Advertisement
 
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
Try re-gapping the plugs first.
Clean the MAF
Check your coils.
And up your fuel quality where possible.


I work on the simplest fix first, though my research is based on worst case scenario.
Saabretooth is offline  
Status: -
Unregistered
 
Join Date: Nov 2013
Location: Russian Federation
County: Moscow
Posts: 59

Member car:

Alfa

Regapping the plugs ? Why give advice like this ?
This is silly, it even says on the spark plugs box NOT TO regap.
Aleator is offline  
jwq
Status: driving Giulia Veloce AWD
Club Member
Membro Premio
 
jwq's Avatar
 
Club Member Number: 857
Join Date: Jan 2005
Location: The Netherlands
County: Zuid Holland
Posts: 6,715
Garage
On my Fiat barchetta with Novitec turbo, Novitec specified colder plugs....
Fiat barchetta turbo
My Turbocharged barchetta
jwq is online now  
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
Quote:
Originally Posted by Aleator View Post
Regapping the plugs ? Why give advice like this ?
This is silly, it even says on the spark plugs box NOT TO regap.
Sure. . When you have higher compression. . You're coils work harder to fire.... thus possible hesitation and misfires.
Saabretooth is offline  
(Post Link) post #6 of 18 Old 21-01-14 Thread Starter
Status: -
AO Member
 
deeznuts's Avatar
 
Join Date: Mar 2007
Location: Denmark
County: Arhus
Posts: 53

Member car:

159 Ti 2.4

Holy sh** - spark plugs every 10.000 km!

I got it running better now having cleaned the coils and plugs for oil, and cleaned the MAF.

I will order a set of spark plugs a tad colder than the factory, and change the engine+gear oil.
deeznuts is offline  
jwq
Status: driving Giulia Veloce AWD
Club Member
Membro Premio
 
jwq's Avatar
 
Club Member Number: 857
Join Date: Jan 2005
Location: The Netherlands
County: Zuid Holland
Posts: 6,715
Garage
Quote:
Originally Posted by deeznuts View Post
Holy sh** - spark plugs every 10.000 km!

.....
Yep, but those were standard plugs, no fancy platinum, only 4 pcs needed, so no big deal
jwq is online now  
(Post Link) post #8 of 18 Old 22-01-14 Thread Starter
Status: -
AO Member
 
deeznuts's Avatar
 
Join Date: Mar 2007
Location: Denmark
County: Arhus
Posts: 53

Member car:

159 Ti 2.4

Is it normal for these engines to have a idle at around 1000 rpm and then once every 20 secs, go up and down just to settle at 1000 a couple of seconds later?
deeznuts is offline  
Status: -
AO Platinum Member
 
Ralf S.'s Avatar
 
Join Date: Feb 2002
Location: The land that Time forgot
Posts: 13,073
You should run the hottest plugs you can. Cold plugs tend to foul up. If the plugs don't look very white or have a "melted" appearance then just replace them with new ones of the same grade. If they're white/melted then you need colder plugs.

If it's a turbo, you have less compression ratio, not more.. so you don't need to re-gap the plugs from standard. Your biggest issue with a turbo is likely to be heat.

The beast should idle fairly cleanly but if the turbo is enormous then your idle will be lumpy. If it doesn't stall and picks up cleanly then there probably isn't a severe issue in there.


Ralf S.

No bullets for Chaingun..
Ralf S. is offline  
Status: if it works, take it apart to finde out why
AO Silver Member
 
GTV-TB's Avatar
 
Join Date: Dec 2008
Location: Sweden
County: Skåne
Posts: 1,164

Member car:

GTV-TB

I do not think Saabretooth is talking about compression ratio but compression pressure (dynamic) and sometimes you need to re-gap the plugs (smaller gap) to avoid misfires when you have boost pressure.
GTV-TB is offline  
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
Thanks GTV.... my terminology is incorrect.. but I'm glad someone understands me...


Correct me if I am wrong.... a TS TURBO set up is going to be running more power.

Your stock plugs are good for stock NA engine. No regapping required.

The CR of an NA engine will be higher than that of a TC engine.

A TC engine will have lower CR, but at point of combustion will have higher overall pressure in the chamber.

Simple logic dictates that when running higher compression or higher power, having a reduced gap allows the arcing to be easier, with less stress on the coils.

The logic is to check the plugs and gaps, and if necesscary, to regap.
Without coming up with any $, or doing anything extra, we rule out on a simple scenario first.
Then moving on to the next set of potential causes.

Its a wonder why people pay arm and tooth to maintain their cars without ruling out the simplest issues first.

But hey, like I said, I could be wrong... and you guys are the smart ones.... I just wasted time troubleshooting only.....
Saabretooth is offline  
Status: -
Unregistered
 
Join Date: Nov 2013
Location: Russian Federation
County: Moscow
Posts: 59

Member car:

Alfa

You can get spark plugs with lower gap from factory, regapping modern spark plugs is silly to say the least.
Aleator is offline  
Status: Race cars in progress
AO Silver Member
 
Gertie's Avatar
 
Join Date: Oct 2007
Location: South Africa
County: Gauteng
Posts: 5,994
Garage
Quote:
Originally Posted by GTV-TB View Post
I do not think Saabretooth is talking about compression ratio but compression pressure (dynamic) and sometimes you need to re-gap the plugs (smaller gap) to avoid misfires when you have boost pressure.
Good page to reference total compression / dynamic compression / effective compression:
Blower Intro
Working in bar make the calculation easier:
The quick formula is: Tot_Comp = (1 + boost) * CR

Quote:
Originally Posted by Aleator View Post
Regapping modern spark plugs is silly to say the least.
Why should this be silly? It has been done for years. Sparkplug technology and ignition technology has just come closer to each other that most just use the default settings - designers just made it easier for mechanics
Gertie is offline  
Status: -
Unregistered
 
Join Date: Nov 2013
Location: Russian Federation
County: Moscow
Posts: 59

Member car:

Alfa

Because modern spark plugs are NOT gapable, says so right on the box, for those who can read.
I will not get into technical arguments, but they are NOT gapable due to how the electrodes are built.
You can always get spark plugs with lower gap from factory, but I wrote that before, just one post above.

A lot of things "have been done for years" but are now obsolete.
Aleator is offline  
Status: Race cars in progress
AO Silver Member
 
Gertie's Avatar
 
Join Date: Oct 2007
Location: South Africa
County: Gauteng
Posts: 5,994
Garage
Quote:
Originally Posted by Aleator View Post
Because modern spark plugs are NOT gapable, says so right on the box, for those who can read.
I will not get into technical arguments, but they are NOT gapable due to how the electrodes are built.
You can always get spark plugs with lower gap from factory, but I wrote that before, just one post above.

A lot of things "have been done for years" but are now obsolete.
NGK Spark Plugs USA
Quote:
If adjusting the gap on fine wire or precious metal plugs such as platinum or iridium be very careful not to apply any pressure or prying force to the fine wire center electrode or insulator as they can be damaged. The gap should be adjusted by only moving the ground electrode
Spark plug gap | NGK Spark Plugs UK
Quote:
The re-gapping of fine wire spark plugs that have very small diameter platinum or iridium alloy electrodes is not recommended due to the risk of damaging the electrodes. Virtually all NGK spark plugs are set to the correct gap for the catalogue applications at the point of manufacture.
This application is not a n OEM application - it is a modified application - thus modifications are needed. The manufacturer needs to warn the "man-on-the-street" of the delicacy of the situation, thus tell him not to try and change the gap. This is to protect themselves.
Gertie is offline  
Status: if it works, take it apart to finde out why
AO Silver Member
 
GTV-TB's Avatar
 
Join Date: Dec 2008
Location: Sweden
County: Skåne
Posts: 1,164

Member car:

GTV-TB

Quote:
Originally Posted by Gertie View Post


This application is not a n OEM application - it is a modified application - thus modifications are needed. The manufacturer needs to warn the "man-on-the-street" of the delicacy of the situation, thus tell him not to try and change the gap. This is to protect themselves.
GTV-TB is offline  
Status: -
Unregistered
 
Join Date: Nov 2013
Location: Russian Federation
County: Moscow
Posts: 59

Member car:

Alfa

OK, my mistake for trying to talk some sense into people. Will do my best not to let it happen again.
Aleator is offline  
Status: Race cars in progress
AO Silver Member
 
Gertie's Avatar
 
Join Date: Oct 2007
Location: South Africa
County: Gauteng
Posts: 5,994
Garage
Quote:
Originally Posted by Aleator View Post
OK, my mistake for trying to talk some sense into people. Will do my best not to let it happen again.
No need to be offended or get defensive - this is a forum where opinions, thoughts and most of all experiences are shared. Your warning on spark-plug gapping opened a worth-while discussion
Gertie is offline  
Reply

Go Back   Alfa Romeo Forum > Supported Alfa Romeo Models > Technical & Vehicle Assistance > Tuning & Upgrades

Tags
156 , bought , novitec , plugs , spark , turbo

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may 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

 
For the best viewing experience please update your browser to Google Chrome