749 / 730 ECM big injectors, here we go again
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From: RI
Car: 93 Caprice 9C1
Engine: L05
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Wow, that's interesting. I'll let the Impala SS community know, if they care. It's only a 5.6% difference in flow but I do remember people saying they had to adjust the offset tables to get it just right. Unless I missed something, 39psi was "common knowledge." You know how "common knowledge" can be...
Joined: Jul 1999
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From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Originally posted by kevm14
Wow, that's interesting. I'll let the Impala SS community know, if they care. It's only a 5.6% difference in flow but I do remember people saying they had to adjust the offset tables to get it just right. Unless I missed something, 39psi was "common knowledge." You know how "common knowledge" can be...
Wow, that's interesting. I'll let the Impala SS community know, if they care. It's only a 5.6% difference in flow but I do remember people saying they had to adjust the offset tables to get it just right. Unless I missed something, 39psi was "common knowledge." You know how "common knowledge" can be...
Im not shy around here, and alot of people dislike me for it. But whatever. I always try to do and say what I feel is right.
Here is a link to one of my posts. There were some followups about a year later in another thread, but I can't find it:
https://www.thirdgen.org/techbb2/sho...hreadid=219294
-- Joe
Last edited by anesthes; Feb 2, 2006 at 07:06 PM.
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From: garage
Engine: 3xx ci tubo
Transmission: 4L60E & 4L80E
Did some ECM tuning this weekend to see if it is possible to get this setup to work with new Ford 42#/hr green tops.
355ci
730 ECM w/ $58 BBZB 749 code
216@.050" cam (both I & E), -4* overlap @.050"
LT1 intake, 48mm TB
two T3 .63 A/R corks in the exhaust
Worked with various spark & fuel tables. The most influencial table was the BPW linearity table. Second most was the closed throttle VE table.
Tuning started with a BPW of 1.5ms. That is, two 1.5ms squirts every 720*. WBO2 AFR was about 13.0. The min BPW tables were set at .5 to enter single fire mode. In the end, the BPW was 1.2ms +/- .2ms at 750 rpm. Timing set at 26* w/r/t TDC.
Idle fluctuated about 100 rpm. When the coolant fan kicked on it would cause the stall saver to engage sometimes. Overall, not very good but streetable. Turning the idle to 800-850 rpm helped but sounded like it was too high of an idle. BPW were about 1.3ms. The BPW is VERY sensitive at idle. Changing closed throttle VE by .3 made a huge difference in AFR and idle quality.
In the end, this shows that saturated using double fire batch is a waste of time when big injectors are installed. Sure, it runs decent. But BPW that low even with "linear saturated injectors" are very close to the borderline of not turning on. If they get slightly clogged it throws the fuel WAY off. It is a marginal setup.
I am going to try going using the single fire mode to get the idle BPW up in the 2.0ms range. This is the only way I see it working properly. The issue then becomes the transistion between single fire to batch fire. New tables to mess with I guess.
This all applies to double fire batch mode. SEFI does not apply.
Figured I would post in case anyone is looking to install saturated injectors with double fire ECM.
355ci
730 ECM w/ $58 BBZB 749 code
216@.050" cam (both I & E), -4* overlap @.050"
LT1 intake, 48mm TB
two T3 .63 A/R corks in the exhaust
Worked with various spark & fuel tables. The most influencial table was the BPW linearity table. Second most was the closed throttle VE table.
Tuning started with a BPW of 1.5ms. That is, two 1.5ms squirts every 720*. WBO2 AFR was about 13.0. The min BPW tables were set at .5 to enter single fire mode. In the end, the BPW was 1.2ms +/- .2ms at 750 rpm. Timing set at 26* w/r/t TDC.
Idle fluctuated about 100 rpm. When the coolant fan kicked on it would cause the stall saver to engage sometimes. Overall, not very good but streetable. Turning the idle to 800-850 rpm helped but sounded like it was too high of an idle. BPW were about 1.3ms. The BPW is VERY sensitive at idle. Changing closed throttle VE by .3 made a huge difference in AFR and idle quality.
In the end, this shows that saturated using double fire batch is a waste of time when big injectors are installed. Sure, it runs decent. But BPW that low even with "linear saturated injectors" are very close to the borderline of not turning on. If they get slightly clogged it throws the fuel WAY off. It is a marginal setup.
I am going to try going using the single fire mode to get the idle BPW up in the 2.0ms range. This is the only way I see it working properly. The issue then becomes the transistion between single fire to batch fire. New tables to mess with I guess.
This all applies to double fire batch mode. SEFI does not apply.
Figured I would post in case anyone is looking to install saturated injectors with double fire ECM.
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From: Dallas, TX area
Car: 91 Formula WS6 (Black, T-Tops)
Engine: 383 MiniRam (529 HP, 519 TQ - DD2K)
Transmission: Built '97 T56, Pro 5.0, CF-DF
Axle/Gears: 4.11 posi Ford 9"
Originally Posted by anesthes
I think it all stems from people assuming the injectors were rated at whatever rail pressure the fords used. I remember some guys on here calling me retarded for saying I think thats false, so finally I sent a set, then another set to be checked. Then some others did the same..
Im not shy around here, and alot of people dislike me for it. But whatever. I always try to do and say what I feel is right.
Here is a link to one of my posts. There were some followups about a year later in another thread, but I can't find it:
https://www.thirdgen.org/techbb2/sho...hreadid=219294
-- Joe
Im not shy around here, and alot of people dislike me for it. But whatever. I always try to do and say what I feel is right.
Here is a link to one of my posts. There were some followups about a year later in another thread, but I can't find it:
https://www.thirdgen.org/techbb2/sho...hreadid=219294
-- Joe
SVO 30's are 30lb/hr at 43.5 PSI, no question.
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From: garage
Engine: 3xx ci tubo
Transmission: 4L60E & 4L80E
Is www.cruizinperformance.com still in business? The page comes up as unknown. I have a set of P&H that I want to get cleaned & flowed.
Anyone else out there do a good job at cleaning them?
Thanks,
J
Anyone else out there do a good job at cleaning them?
Thanks,
J
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Joined: Aug 2001
Posts: 1,008
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From: NJ/PA
Car: Yes
Engine: Many
Transmission: Quite a few
Originally Posted by vernw
Yep, I'm one of those folks who sent some SVO 30's to Rich at CruizinPerformance.com, and he tests them at 43 PSI, not the 39 Fords are supposed rated at. And guess what? Mine all tested between 30 and 31 after being cleaned, etc.
SVO 30's are 30lb/hr at 43.5 PSI, no question.
SVO 30's are 30lb/hr at 43.5 PSI, no question.
Joined: Apr 2004
Posts: 3,180
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From: Browns Town
Car: 86 Monte SS (730,$8D,G3,AP,4K,S_V4)
Engine: 406 Hyd Roller 236/242
Transmission: 700R4 HomeBrew, 2.4K stall
Axle/Gears: 3:73 Posi, 7.5 Soon to break
Mine were the same as Vern's.
43.5 psi gets 30-30.5 lbs/hr across the board on the red tops.
Confirmed again.
43.5 psi gets 30-30.5 lbs/hr across the board on the red tops.
Confirmed again.
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