Accel Enrichment

Covers all sn94/95 mustang v8 ecu's.
Blocmi
Posts: 26
Joined: 2021 Feb 16, 11:13
Location: Connecticut
Vehicle Information: 1995 Mustang GT, CBAZA, 11:1 306, Ported Windsor Sr. aluminum heads 2.02/1.60, Trick Flow Track Heat, 24lb injectors, Comp cams 294/306 (2,800-7,000), Shorty headers, X-Pipe, Reverse Manual VB C4, 4100 stall converter, 4:10, MT ET Drag 26-10-15

Accel Enrichment

Unread post by Blocmi »

New motor in the bracket car and I'm having some issues with a bog off the line. It seems to get worse with poor air conditions.

I think it may be caused by being a bit too lean off the line from the initial hit to about 1-1.5 seconds out.

I don't know if it would make a difference in what to adjust but I'm coming up on the converter to about 2300 rpm, so the initial hit isn't from closed throttle, it is from about 1.65v TP.

Do I reduce Manifold Volume or TSEIF or both in CBAZA to add pump shot?

Since the car is a track only car, would there be any down side to adjusting 320A so I once I come up on the converter I am in open loop?
My thinking is, if the fuel is already there, it won't need as much enrichment and may be a little more consistent.
decipha
Posts: 4952
Joined: 2021 Feb 15, 12:23
Location: Metairie, LA
Vehicle Information: Work Truck
'19 F-150 3.3L

Re: Accel Enrichment

Unread post by decipha »

reduce manifold volume

ita not uncommon for fueling to be off on new engines til everything seats you build up your permanent puddle and carbon etc...
patricktjms
Posts: 4
Joined: 2021 May 20, 11:59
Location: Muncie, Indiana
Vehicle Information: 1994 GT 5.0 Brodix ST 5.0 heads, 1/2" intake spacer, Deka 60lb, adj fuel reg, 255Lph walbro, Factory cam and intake, C4 w/FTI converter, 4.10, 28x9 slick.

Re: Accel Enrichment

Unread post by patricktjms »

I have had the same issue for a year now and can't rid my car of it. Same bog. Manifold volume doesn't do anything. I also leave at about 2000 rpm. Would love to find a way to richen with tps rate of change or something like that.

I always run in open loop all the time and the car will print time slips, but the bog is tricky for reaction times.
Blocmi
Posts: 26
Joined: 2021 Feb 16, 11:13
Location: Connecticut
Vehicle Information: 1995 Mustang GT, CBAZA, 11:1 306, Ported Windsor Sr. aluminum heads 2.02/1.60, Trick Flow Track Heat, 24lb injectors, Comp cams 294/306 (2,800-7,000), Shorty headers, X-Pipe, Reverse Manual VB C4, 4100 stall converter, 4:10, MT ET Drag 26-10-15

Re: Accel Enrichment

Unread post by Blocmi »

patricktjms wrote: 2021 Jun 14, 15:23 I have had the same issue for a year now and can't rid my car of it. Same bog. Manifold volume doesn't do anything. I also leave at about 2000 rpm. Would love to find a way to richen with tps rate of change or something like that.

I always run in open loop all the time and the car will print time slips, but the bog is tricky for reaction times.
I had already tried Air_Man_vol previously, and it helped a little but didn't solve the issue. So I set the base fuel table to .875 for everything above .40 perload and set 320A to .40 which forced open loop and enriched fueling when I come up on the converter, but it will use the O2 for idle and driving in pits.
Keep in mind this is for a drag racing tune, only intended for WOT, not street driving.

What is showed me was that my fueling was way off in lower MAFV points, with load on the engine. The converter stalls so high, I'm either at 1v or 4v+ except for about one second on launch. I had not accurately adjusted the MAF points from 1v to 4v and I was lean on launch because of it.

The car seemed better after adding more fuel, but I only got one pass in after the MAF adjustment so I still need to make some more passes to confirm the MAF transfer was my issue.

On a side note... seems like we trying to accomplish the same thing with our tunes. What changes have you made in your tune to try and improve consistency?
I'm looking for things like making spark act like a fixed distributor with timing full in from launch thru the entire pass.
patricktjms
Posts: 4
Joined: 2021 May 20, 11:59
Location: Muncie, Indiana
Vehicle Information: 1994 GT 5.0 Brodix ST 5.0 heads, 1/2" intake spacer, Deka 60lb, adj fuel reg, 255Lph walbro, Factory cam and intake, C4 w/FTI converter, 4.10, 28x9 slick.

Re: Accel Enrichment

Unread post by patricktjms »

Honestly the main things that make it an awesome bracket car are the big loose FTI converter, c4, and lots of money in suspension. Aside from that, mine likes to be lean which is my main struggle. Pretty sure I have everything below 75 load set to 1.00 and I just watch that the narrow 02 sensors are hovering around or slightly above 800 downtrack. For bracket racing the car won't move more than 3 thousanths from noon to midnight but that creates a hesitation that makes me .050 on the tree when I deck it. But it just won't repeat down track unless its lean. I probably need to spend some time fattening it up way down low in the maf xfer and see what happens.
patricktjms
Posts: 4
Joined: 2021 May 20, 11:59
Location: Muncie, Indiana
Vehicle Information: 1994 GT 5.0 Brodix ST 5.0 heads, 1/2" intake spacer, Deka 60lb, adj fuel reg, 255Lph walbro, Factory cam and intake, C4 w/FTI converter, 4.10, 28x9 slick.

Re: Accel Enrichment

Unread post by patricktjms »

Mine is just a stock shortblock 302 with Brodix 2.02/1.60 heads, stock intake, stock MAF, 60lb deka inj, short headers into 40 series Flowmaster, c4, 4600 fti, 4.10 gear and a 28" stiff side M/T. Double adjustable shocks and struts, good rear control arms.
Blocmi
Posts: 26
Joined: 2021 Feb 16, 11:13
Location: Connecticut
Vehicle Information: 1995 Mustang GT, CBAZA, 11:1 306, Ported Windsor Sr. aluminum heads 2.02/1.60, Trick Flow Track Heat, 24lb injectors, Comp cams 294/306 (2,800-7,000), Shorty headers, X-Pipe, Reverse Manual VB C4, 4100 stall converter, 4:10, MT ET Drag 26-10-15

Re: Accel Enrichment

Unread post by Blocmi »

Looks like our setups are very similar.

I'm running a set of ported Windsor Sr. Aluminum heads with 2.02/ 1.60 on top of some old TRW domed pistons, 294/306 duration cam.
Reverse manual C4 with a Dynamic TCT converter that stalls around 4500, 4:10 gearing on 26" slicks, tubular control arms, single adjustable rears.

I'm not running the time I was aiming for, most likely from too big of a cam, but I picked up the short block, cam and lifters for $200... Fresh rebuild, never fired, had to try as-is for that price.

Last year I was pretty consistent down track with most of my variation happening in the 60, but it was predictable for the most part. Was running 12.80's @103, 1.75 60's, with a 180K stock bottom and home ported GT40 heads and intake.

This year, it's just been a basket case trying to get this new combo to work. Best of 12.48 @108, 1.80 60. I had been hoping to go low 12's, high 11's. Pretty disappointing seeing how I was almost there with factory heads and intake... Just the wrong combination of parts, but for the price, I had to try. At this point I'm done looking to go any quicker, I just need to find the consistency to be competitive.

I was running the base fuel table same as you, but I think I'll keep enriching it before launch for a few weeks and see if my 60's are more consistent.

I've previously tried going richer and leaner than .875, but I didn't see any difference in MPH so I just left it at .875. Maybe once I get the fuel dialed in throughout the whole pass, I'll lean it out a bit and see if consistency improves.
patricktjms
Posts: 4
Joined: 2021 May 20, 11:59
Location: Muncie, Indiana
Vehicle Information: 1994 GT 5.0 Brodix ST 5.0 heads, 1/2" intake spacer, Deka 60lb, adj fuel reg, 255Lph walbro, Factory cam and intake, C4 w/FTI converter, 4.10, 28x9 slick.

Re: Accel Enrichment

Unread post by patricktjms »

60' consistency for me is all about the shocks. Try all the way loose on the shocks and give them a click each pass and it will tell you when its too much. Mine goes 1.68 every pass. Never moves more than a thou or 2. If it moves 5 or 6 thou you can almost guarantee it was a staging error. My inconsistencies from fuel always show up between 330 and 660 feet.

I always run mine pretty warm too. 185 ect min and trans at 150 when I pull into the water. That way I don't have to struggle to cool down later in the rounds.
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