[home][rumors and news][model release matrix][dealer network][desktop calendar][exhaust notes][tov forums][links][search][sponsors][garage][login]

Tire Rack Upgrade Garage
 Search for a Dealer:
 Canadian Flag US Flag
 Honda Acura
 ZIP  
NSX GT3 Evo To Compete Globally in 2019
More.......................
2019 Acura ILX Arrives with Dynamic New Styling, Major Technology Upgrades and New A-Spec Treatment
More.......................
Honda Joins with Cruise and General Motors to Build New Autonomous Vehicle
More.......................
Honda reports September 2018 sales numbers
More.......................
Honda recalling 232,000 2018 Accords and 2019 Insights for rear camera software update
More.......................
2019 Accord arriving in showrooms by November
More.......................
Is a base trim of the Civic Type R finally arriving for MY 2019? (More MY2019 info inside)
More.......................
Team Honda Research wins ST2 at NASA Nationals with their NC1 NSX
More.......................
TLX --> Re: My TLX so far
Join Discussion......
Amateur Racing & Driving --> Re: TSX @ NCCAR Apexfest
Join Discussion......
Today's Reading Links --> Re: European CO2 madness and why electromobility is pointless
Join Discussion......
Today's Reading Links --> Re: "2019 Toyota Supra Is a BMW Parts Bin Car"
Join Discussion......
Fuel Cell Technology --> DMV Stickers, we don't need no stinking stickers
Join Discussion......
Type R --> Re: DC-R
Join Discussion......
Clarity --> Re: Clarity PHEV Owner
Join Discussion......
Today's Reading Links --> Re: Tesla’s Model 3 Is Becoming One of America’s Best-Selling Sedans
Join Discussion......
General Talk --> Model Release Matrix?
Join Discussion......
General Talk --> Re: Fixing SH-AWD
Join Discussion......
General Talk --> Re: CR-V Hybrid 4wd iMMD
Join Discussion......
General Talk --> Re: BMW Drops 3-Series Manual Globally... Audi A4 too...
Join Discussion......
Professional Motorsports --> Re: IMSA finale
Join Discussion......
Civic --> Re: 2019 Civic Accessories
Join Discussion......
General Talk --> Re: Goodbye TL-S 6MT
Join Discussion......
First Drive: 2019 Honda Insight
Read Article....................
2019 Honda Insight PR Photo Gallery
Read Article....................
First Drive: 2019 Acura RDX
Read Article....................
2019 Acura RDX Features & Specifications
Read Article....................
PR Photo Gallery - 2019 Acura RDX Advance
Read Article....................
PR Photo Gallery - 2019 Acura RDX A-Spec
Read Article....................

[fancy] [flat] [simple]
TOV Forums > Strictly Technical > > Re: Why Carbon fouling may not be an issue for Honda DI engines

Go to:

Viewing Threshold (What is this?)

Thread Page - [1]
Author
  Post New Thread
silverf16
Profile for silverf16
Why Carbon fouling may not be an issue for Honda DI engines    (Score: 1, Normal) 08-12-2017 03:31
Reply to This Message Attach Quote to Reply
This technical report states the use of split injection as a method to reduce carbon build up on intake valves.

Section 4.2.3 in the report below describes the process of split injections. The graphs in this section shows the injection events. I gathered that injection is occurring twice per engine cycle - First, injecting at 90 degrees after TDC, when the intake valves are open. It then injects again at BDC at 180 degrees during the beginning of the compression stroke. Honda doesn't spell it out exactly but study the graph.

By injecting when the intake valves are open, fuel is cleaning the backside of the valves. The injector is located between both intake valves hence it will hit both valves. Whether the spray pattern from the 6-port injector will hit the ENTIRE back surface of the intake valves is an unknown. But we know the first injection is effectively cleaning at least some portion of the valve hence reducing carbon build up.

Granted, the graph and text indicate that split injection increases fuel efficiency by 1% and reduces soot production because it has a more homogeneous mixture with a more stable air/fuel ratio.

This report is for the the 2.4 Naturally aspirated engine. Draw your own conclusion on how this strategy may also benefit Turbo engines.

I understand most of the report, but not all of it. If you are an engine person, you may uncover additional details that you can elaborate for us.

There you have it - One of Honda's strategy for reducing carbon build up.

https://hondakarma.com/data/attachment-files/2015/09/89991_Honda_2.4_L_Direct-Injection_Gasoline_Engine.pdf

notyper
Profile for notyper
Re: Why Carbon fouling may not be an issue for Honda DI engines    (Score: 1, Normal) 08-12-2017 04:34
Reply to This Message Attach Quote to Reply
Most DI engine makers use a split injection scheme, at least at lower rpms and loads (up to about 3000 rpm or so). Some use more than 2 injection events as well (although not as many as the diesel folk do).

At higher rpms and loads there really isn't the time for split injection.

SC

Nick GravesX
Profile for Nick GravesX
Re: Why Carbon fouling may not be an issue for Honda DI engines    (Score: 1, Normal) 08-12-2017 05:43
Reply to This Message Attach Quote to Reply
I was aware of Inlet Gas Recirculation, but I'd forgotten about it!

 
Thread Page - [1]
Go to:
Contact TOV | Submit Your Article | Submit Your Link | Advertise | TOV Shop | Events | Our Sponsors | TOV Archives
Copyright © 2018 Velocitech Inc. All information contained herein remains the property of Velocitech Inc.
The Temple of VTEC is not affiliated with American Honda Motor Co., Inc. TOV Policies and Guidelines - Credits - Privacy Policy
29 mobile: 0