Injector sizing, 12V (& somewhat auto trans) specific!
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From: Central PA
Injector sizing, 12V (& somewhat auto trans) specific!
Currently I've got a #10 (forward) and stock 180 injectors.
I recently snagged up a 14cm WG housing, and am going to have HTT rebuild the turbo and put the 60mm wheel in it.. basically, the 35/40 hybrid. At the same time, I'll grind the plate to 100.
Here's my question about new injectors-
My basic choice is 215's (or the EDM quiv), or 370's (again or the EDM equivalent)
If I do the 215's, I would leave my plate up further, which lengthens the injector pulse cycle, right? (This effectively retards injector timing)
But, with the bigger (370 size) injectors, I'd pull the plate back to basically provide a similar amount of TOTAL fuel as the above combo, but since it'll dump that fuel in heavier but in a shorter pulse, would it effectively advance the timing, and therefore help EGT's and increase MPG?
Or am i totally off in how the plate controls total fuel?
My reason for wanting to pull the plate back is auto trans related - line pressure & shift points are very dependant on pedal position, so just controlling EGT's with my foot has other consequences that a 5-speed guy wouldn't have. (earlier / softer shifts, lower line pressure, etc)
Long term goal is small twins, so the bigger injector idea is what I am leaning towards, so I wouldn't have to replace the injectors when I add the big turbo. (Using the 35/40 as the top)
Yeah, I'm ****... the whole "Just toss in 370's and just control EGT's with your foot, and blow smoke at every turn" just doesn't sit well with me. Neither does reduced MPG's.. This pig needs all the help she can get..
I recently snagged up a 14cm WG housing, and am going to have HTT rebuild the turbo and put the 60mm wheel in it.. basically, the 35/40 hybrid. At the same time, I'll grind the plate to 100.
Here's my question about new injectors-
My basic choice is 215's (or the EDM quiv), or 370's (again or the EDM equivalent)
If I do the 215's, I would leave my plate up further, which lengthens the injector pulse cycle, right? (This effectively retards injector timing)
But, with the bigger (370 size) injectors, I'd pull the plate back to basically provide a similar amount of TOTAL fuel as the above combo, but since it'll dump that fuel in heavier but in a shorter pulse, would it effectively advance the timing, and therefore help EGT's and increase MPG?
Or am i totally off in how the plate controls total fuel?
My reason for wanting to pull the plate back is auto trans related - line pressure & shift points are very dependant on pedal position, so just controlling EGT's with my foot has other consequences that a 5-speed guy wouldn't have. (earlier / softer shifts, lower line pressure, etc)
Long term goal is small twins, so the bigger injector idea is what I am leaning towards, so I wouldn't have to replace the injectors when I add the big turbo. (Using the 35/40 as the top)
Yeah, I'm ****... the whole "Just toss in 370's and just control EGT's with your foot, and blow smoke at every turn" just doesn't sit well with me. Neither does reduced MPG's.. This pig needs all the help she can get..
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From: Laredo
If this is ur case
I wouldnt hessitate from doing the large injectors until u get the twins in. i ran 370s for a bit with stock stix and a zero plate.. MAN!! too much smoke for my liking... I run sstock stix adn a "banks" HX 35 turbo... (whopee) At 16.5 degree timing ur fuel should burn more efficiently with twins but ur still gonna have the smoke like u say. that 215 pump flows ALOT of fuel. AS far as ur plate positioning, i have 5 speeds, sorry, cannot help u...
But if u go 370s, just move plate farther back till u get smoke level u can deal with, then once u get twins, just bump plate forward..
Tx
I wouldnt hessitate from doing the large injectors until u get the twins in. i ran 370s for a bit with stock stix and a zero plate.. MAN!! too much smoke for my liking... I run sstock stix adn a "banks" HX 35 turbo... (whopee) At 16.5 degree timing ur fuel should burn more efficiently with twins but ur still gonna have the smoke like u say. that 215 pump flows ALOT of fuel. AS far as ur plate positioning, i have 5 speeds, sorry, cannot help u...
But if u go 370s, just move plate farther back till u get smoke level u can deal with, then once u get twins, just bump plate forward..
Tx
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From: Raleigh, NC
Eskimo,
Come to the Durham Dyno day, you can see the smoke my truck puts out with my NEW 370's. NOT bad at all. If you drive like a human there is virtually no smoke, roll into it the same result. Now if you "drop the hammer" at a dead stop and push it to the floor-Yea smoke.
Come to the Durham Dyno day, you can see the smoke my truck puts out with my NEW 370's. NOT bad at all. If you drive like a human there is virtually no smoke, roll into it the same result. Now if you "drop the hammer" at a dead stop and push it to the floor-Yea smoke.
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From: Central PA
MC - thanks for the offer... I was out in Charlotte yesterday - wife wanted to go out there for her birthday...
I'm very much looking forward to tax time this year.. Should be enough for stacks with a muffler, the upgraded turbo, and injectors..
Anyone else have input, especially as it related to MPG?
I'm very much looking forward to tax time this year.. Should be enough for stacks with a muffler, the upgraded turbo, and injectors..
Anyone else have input, especially as it related to MPG?
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From: Saskatoon, Sk, Canada
I lost a couple MPG's when I installed my 215's, about 80Km (50 miles) per tank. I've got my plate in the stock position and AFC centered. Sliding the plate forward gave me high EGT's. Moving the AFC forward gave me tons of smoke and not great low end with the tight converter. I still can lay out a decent cloud of smoke at WOT. EGT's will eventually hit 1300 at the upper end of 3rd gear.
About the only difference in our set-ups is the straight pipe and Scotty vs. BHAF. A 4" exhaust is next for me. I'm glad I didn't go with 370's. I can't drive constantly controlling EGT's with my right foot. No fun.
I'd go with the 215's. If you want to go bigger when you get your twins, you can sell them easy.
About the only difference in our set-ups is the straight pipe and Scotty vs. BHAF. A 4" exhaust is next for me. I'm glad I didn't go with 370's. I can't drive constantly controlling EGT's with my right foot. No fun.
I'd go with the 215's. If you want to go bigger when you get your twins, you can sell them easy.
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From: Raleigh, NC
Eskimo,
I dynoed at 310/674 on Saturday, with ONLY the 370's, 4" exhaust, AFE and a turbo master! I have not even had a chance to drop in my fuel plate yet!! I cannot get the EGT's above 1100* with the above mentioned mods. Do the 370's you will LOVE them!!
, I bought mine for 400 bucks and that included a cam plate!!! Yes, they are new!!
I dynoed at 310/674 on Saturday, with ONLY the 370's, 4" exhaust, AFE and a turbo master! I have not even had a chance to drop in my fuel plate yet!! I cannot get the EGT's above 1100* with the above mentioned mods. Do the 370's you will LOVE them!!
, I bought mine for 400 bucks and that included a cam plate!!! Yes, they are new!!
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From: Central PA
Originally Posted by berner
I lost a couple MPG's when I installed my 215's, about 80Km (50 miles) per tank. I've got my plate in the stock position and AFC centered. Sliding the plate forward gave me high EGT's. Moving the AFC forward gave me tons of smoke and not great low end with the tight converter. I still can lay out a decent cloud of smoke at WOT. EGT's will eventually hit 1300 at the upper end of 3rd gear.
About the only difference in our set-ups is the straight pipe and Scotty vs. BHAF. A 4" exhaust is next for me. I'm glad I didn't go with 370's. I can't drive constantly controlling EGT's with my right foot. No fun.
About the only difference in our set-ups is the straight pipe and Scotty vs. BHAF. A 4" exhaust is next for me. I'm glad I didn't go with 370's. I can't drive constantly controlling EGT's with my right foot. No fun.
I know my pipe vs. a 4" is hurting me a little bit, but with my plate almost full forward, I don't get past 1300 until well into 4th gear, and it does not go past 1350-1400 at all. It *was* worse before the timing advance though.
MC - That's with a stock fuel plate? Wow.. not bad at all! When I got my truck the stock plate was full forward, and after the 3K & #10 went in at the same time, and it was a whole new animal. Haaaang on!!
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From: Central PA
I might take you up on that - though we need to hang out sometime anyway!
I think I'm more interested in MPG effects than smoke right now - how has yours been doing, or are you having too much fun to pay attention?
I'm pretty sold on the 370's, especially once I get the stacks on..the "hazing at idle" won't be nearly as big a deal then, or if I bite the bullet and get EDM's...
I think I'm more interested in MPG effects than smoke right now - how has yours been doing, or are you having too much fun to pay attention?
I'm pretty sold on the 370's, especially once I get the stacks on..the "hazing at idle" won't be nearly as big a deal then, or if I bite the bullet and get EDM's...
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From: Raleigh, NC
What can I say Foot on the boards is not condusive to good MPG, But I am going out of town Sat and will be looking at that, and I am going to Al in the next few weeks--about 1400 miles round trip so I will report back on MPG then. I really cannot comment with confidence on the around town mileage before or after the 370's as I have not had the truck that long. BUT,First tank full stock was about 17, second was about 15-no highway at all. Now with the 370's I am still above the half mark with 230 or so miles, and that is after 5 Dyno pulls at Durham, Racing around town, etc, etc.
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From: Central PA
hmmm.. my drag race mileage went down about 1/2 MPG over the course of a tank...
Though I've heard alot of milage increases with the bigger injectors once the urge to mat the pedal at every green light fades... (Still waiting for my urges to fade
)
Though I've heard alot of milage increases with the bigger injectors once the urge to mat the pedal at every green light fades... (Still waiting for my urges to fade
)
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From: Northwest, Minnesota USA
Originally Posted by Eskimo
...
If I do the 215's, I would leave my plate up further, which lengthens the injector pulse cycle, right? (This effectively retards injector timing)
But, with the bigger (370 size) injectors, I'd pull the plate back to basically provide a similar amount of TOTAL fuel as the above combo, but since it'll dump that fuel in heavier but in a shorter pulse, would it effectively advance the timing, and therefore help EGT's and increase MPG?
Or am i totally off in how the plate controls total fuel?
...
If I do the 215's, I would leave my plate up further, which lengthens the injector pulse cycle, right? (This effectively retards injector timing)
But, with the bigger (370 size) injectors, I'd pull the plate back to basically provide a similar amount of TOTAL fuel as the above combo, but since it'll dump that fuel in heavier but in a shorter pulse, would it effectively advance the timing, and therefore help EGT's and increase MPG?
Or am i totally off in how the plate controls total fuel?
...
pump advance (most)
fuel plate
pump capacity
injectors (pop off pressure)
delivery valves.
The injectors do their job when the pump delivers enough pressurized fuel to open the pop off valve in each injector. The pop-off closes when the fuel delivery drops below the threshold pressure.
The fuel plate allows the pump to deliver more fuel up to the plunger limit. The start of injection does vary slightly, but mostly more fuel means a longer injection period. That's why advanced pump timing lowers EGTS. It gives fuel delivery (& burn) earlier in the piston stroke.
370 injectors add 30-50 rwhp. A fuel plate adds up to 200 rwhp.
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From: Raleigh, NC
Eskimo,
I am back from Thanksgiving with my folks, here are the MPG results-
tank 1- 14.0 MPG speed about 77, 1800 ish RPM's
tank 2- 13.7 MPG ---same----
tank 3- 12.8 MPG speed was up 85-105, 2200-2700 RPM's
The truck and trailer grossed just under 14,000
That was not a misprint-I was running down I-65 in Bama running with other people at 105!! Boy does this truck run!!
I am back from Thanksgiving with my folks, here are the MPG results-
tank 1- 14.0 MPG speed about 77, 1800 ish RPM's
tank 2- 13.7 MPG ---same----
tank 3- 12.8 MPG speed was up 85-105, 2200-2700 RPM's
The truck and trailer grossed just under 14,000
That was not a misprint-I was running down I-65 in Bama running with other people at 105!! Boy does this truck run!!