CARBURETION for your 4AG

Technical How-To guides contributed by various technically proficient members from our community and voted popular by our members of the community at large.

Moderators: dr.occa, CBR_TOY

Flipp
Tourist
Posts: 34
Joined: Tue Jan 15, 2013 12:49 am

Re: CARBURETION for your 4AG

Post by Flipp »

pierce, wolf creek, paradise and jam engineering all seem to be for big ports =\
the one place i found for a smallport is this place in AUS
http://www.weberperformance.com.au/prod ... cts_id=549" onclick="window.open(this.href);return false;

if anyone knows a place here in the states please hit me back with a link. thanks
∧,,∧
 (;`・ω・)  。・゚・⌒)
 /   o━ヽニニフ))
 しー-J

joel26
VIP Member
Posts: 2069
Joined: Wed Jan 23, 2008 10:30 pm
Location: Spring Tx
Contact:

Re: CARBURETION for your 4AG

Post by joel26 »

^^^ Sorry man that is all i knew.... pm dr.occa he is the carbd guy in the forum..he probably knows were u can find one...
Image

Ae86_abby
Tourist
Posts: 20
Joined: Sat Feb 18, 2012 12:34 am

Re: CARBURETION for your 4AG

Post by Ae86_abby »

Paridise racings website does say small port largeport. Have you emailed them

Sent from my SGH-I727R using Tapatalk 2

Flipp
Tourist
Posts: 34
Joined: Tue Jan 15, 2013 12:49 am

Re: CARBURETION for your 4AG

Post by Flipp »

Ae86_abby wrote:Paridise racings website does say small port largeport. Have you emailed them

Sent from my SGH-I727R using Tapatalk 2
yea i sent all of them an email asking if they made one, ill re check the website. thanks for catching that =]
∧,,∧
 (;`・ω・)  。・゚・⌒)
 /   o━ヽニニフ))
 しー-J

dr.occa
Hades - Site Admin
Posts: 7733
Joined: Tue Sep 04, 2007 1:49 pm
Location: On my hiney...in HOU
Contact:

Re: CARBURETION for your 4AG

Post by dr.occa »

They're normally over $200 before shipping but I could have a custom made one for $180 plus shipping.

demby123
Tourist
Posts: 129
Joined: Thu Feb 02, 2012 10:34 pm
Location: North Texas

Re: CARBURETION for your 4AG

Post by demby123 »

Thinking REALLY hard about going carb when I put a 4age in my SR5 and im trying to get an idea on what i'll need to get a great engine on a budget, but first i have a few questions.

Could you go more into detail on the 4ac dizzy into 4age head using the 4age driven gear? I'm assuming they're riveted in or held in by a pin of somesort? If I do manage to swap the gears and plug locations, I'll have the same timing advance curve as the 4ac?

I plan on rebuilding the engine, since i'm new to carbs(or at least ones that are actually adjustable) do you think its a bad idea to break in an engine on a novice carb setup?

Are there any cheap wideband options? I've heard of people using used oem sensors to obtain AFRs but im not sure how accurate that is.


I want a bike carbed(probably r1) stock rebuilt 4age that gets stock power and can get 25-35 mpg daily driving(with mfactory 5th gear)... is this unrealistic?

dr.occa
Hades - Site Admin
Posts: 7733
Joined: Tue Sep 04, 2007 1:49 pm
Location: On my hiney...in HOU
Contact:

Re: CARBURETION for your 4AG

Post by dr.occa »

As for the 4AC dist - scrap the idea. Since it spins in the opposite direction in 4AC, when it's mated to the 4AGE it'll retard timing rather than advance it as you accelerate. This is bad. For timing either invest in the Megajolt Lite Jr by Autosportlabs or the Programmable (<-this is important) MSD 6AL II (p/n: 6530 IIRC). Though the MSD is a bit more expensive than the Megajolt, it has less parts to source because it works with your distributor for a trigger and just needs to be wired in.

If your jetting is wrong, it's not a good idea to break an engine as it may be too lean or too rich. Too rich of a jetting and the rings will never seal. Too lean and you'll have too much heat not only in the chamber but on the cylinder walls and rings (which need to seat remember).

Innovate is your best bet for an affordable, working wide-band out of the box. That's the most widely known brand for budget minded tuners.

25-35 isn't unreasonable actually for a stock, carbureted 4AG. Nothing larger than 40mm carb bodies and 32 inner venturis (chokes).

demby123
Tourist
Posts: 129
Joined: Thu Feb 02, 2012 10:34 pm
Location: North Texas

Re: CARBURETION for your 4AG

Post by demby123 »

Dang, so theres absolutly no way to spin the 4ac dizzy backwards? (aka the right way for the 4age)

I also read a bit about using the stock ECU to control timing on aeu86 but that method uses a MAP sensor ECU. In theory the ADM bluetop ECU should work in the same way but I'm not exactly sure what sensors it needs to control ignition and how it will react if some sensors are unavailable or faked. I may be able to use the TPS from the R1 carburetors so that leaves the AFM unaccounted for for possible ignition variables.


I'll have to do some research on the jetting... I' not sure if i'd trust myself to get it right on the first start though.
Last edited by demby123 on Sun Jun 09, 2013 8:57 am, edited 1 time in total.

User avatar
Mr. Apex
Tourist
Posts: 16
Joined: Wed Jan 16, 2013 7:52 pm
Location: Ontario California

Re: CARBURETION for your 4AG

Post by Mr. Apex »

Hey Dr. Occa is it possible for me to use a MSD 6A or 6AL for my timming and ignition control on my carbed 4ag?? while stilling using the Bluetop dizzy

dr.occa
Hades - Site Admin
Posts: 7733
Joined: Tue Sep 04, 2007 1:49 pm
Location: On my hiney...in HOU
Contact:

Re: CARBURETION for your 4AG

Post by dr.occa »

The 6A/L will work but it offers no form of timing advance.

The 4AC dizzy will physically spin the correct way for the 4AGE BUT the advance weights and springs are designed to rotate the vr sensors in opposite direction with centrifugal force. They move (clockwise) to advance timing for the 4AC which spins counter clockwise. When inserted in the 4AGE, though the distributor shaft will spin clockwise now, the vr sensors will still rotate clockwise with centrifugal force thereby retarding timing. Clear as mud?

hotlavafrs
Posts: 3
Joined: Fri Aug 01, 2014 12:58 pm
Location: West Des Moines, Iowa

Re: CARBURETION for your 4AG

Post by hotlavafrs »

Does anyone have an actual list of places that Currently make carb manifolds for the 4age? I've found a few but they all seem limited to weber dcoe's. I've seen pictures and build lists of people using other carbs but never get any info on manifolds

dr.occa
Hades - Site Admin
Posts: 7733
Joined: Tue Sep 04, 2007 1:49 pm
Location: On my hiney...in HOU
Contact:

Re: CARBURETION for your 4AG

Post by dr.occa »

What carb(s) do you actually plan on using?

hotlavafrs
Posts: 3
Joined: Fri Aug 01, 2014 12:58 pm
Location: West Des Moines, Iowa

Re: CARBURETION for your 4AG

Post by hotlavafrs »

dr.occa wrote:What carb(s) do you actually plan on using?
Honestly I can't decide. I want to run the cheapest setup I can find, just to get the car moving.

dr.occa
Hades - Site Admin
Posts: 7733
Joined: Tue Sep 04, 2007 1:49 pm
Location: On my hiney...in HOU
Contact:

Re: CARBURETION for your 4AG

Post by dr.occa »

DCOE/Solex style carbs will be your easiest. Intake manifolds, linkages, jets, etc. readily available and well documented. Look up Robert Turnbow on Facebook for a set of Weber DCOEs. Tell him Jonas sent ya.

demby123
Tourist
Posts: 129
Joined: Thu Feb 02, 2012 10:34 pm
Location: North Texas

Re: CARBURETION for your 4AG

Post by demby123 »

Can anyone recommend a reliable fuel pump for under 100 dollars that's as quiet as a bike fuel pump? mined died after the 86 day event put on by the ft86 guys

Post Reply