High pressure injectors on a TBI
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Re: High pressure injectors on a TBI
I was looking through TBI stuff on the auction site and stumbled across this. It adapts high pressure injectors to the TBI. Has anyone here tried anything like this before? How much of a pain would this be to tune? Would this be worth the money?
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Re: High pressure injectors on a TBI
An interesting product. Would probably allow you a wider range of injector types, brands, and flow rates. Will also likely allow you to find injectors when TBI parts start to dry up. But I'm not sure that's going to happen in my lifetime.
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Re: High pressure injectors on a TBI
Thank you for sharing. This looks revolutionary for us TBI guys who are limited by injector size.
If this housing can support the short Bosch 2200cc injectors, big power can be made with this setup.
https://www.injectorsonline.com/us/xspurt-2000-short.html
If this housing can support the short Bosch 2200cc injectors, big power can be made with this setup.
https://www.injectorsonline.com/us/xspurt-2000-short.html
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Re: High pressure injectors on a TBI
OEM GM injectors can support over 500 hp and 50+ psi as is. I have run them with both a 2:1 and 4:1 rising rate FMU with sucess after blocking off the OEM regulator and eliminating the diaphram.
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Re: High pressure injectors on a TBI
BTW, what regulators are you talking? 4:1 rising rate sounds interesting. Is that boosted or under atmospheric pressure?
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Re: High pressure injectors on a TBI
This is an example of the regulator I am talking about. I used the Vortec Super FMU on that setup.
http://www.ebay.com/itm/Vortech-Supe...tZb-Ib&vxp=mtr
A 61# high pressure 350 injector is about 105 lb/hr @ 32 psi in the 454/502 Marine throttle bodies. Running at 50 PSI they flow roughly 125 lb/hr each. I with the mild stock TBI truck cam even with those heads, I ran out of engine before I ran out of fuel even with the blower on it. At a 0.5 bsfc with 2 injectors that is fuel for 500 HP. If one was to run two of the 2" bore 454/Marine TBI units on the same engine with the EBL and the added injector driver you could run two of the TBI units on a blower and support closer to 1,000 hp.
The Mercury 575SCI was a factory supercharged, twin TBI big block that made good power/torque for an engine built for durability. There is a company that converts them to 8-71 blowers.
http://www.dyersblowers.com/187/1676.html
Last edited by Fast355; 09-16-2017 at 12:00 PM.
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Re: High pressure injectors on a TBI
Boosted, when I had a Marine 502 TBI on a Weiand 177 on Dart Iron Eagle 230cc heads on a 350 TBI in my 1983 G20 van.
This is an example of the regulator I am talking about. I used the Vortec Super FMU on that setup.
http://www.ebay.com/itm/Vortech-Supe...tZb-Ib&vxp=mtr
A 61# high pressure 350 injector is about 105 lb/hr @ 32 psi in the 454/502 Marine throttle bodies. Running at 50 PSI they flow roughly 125 lb/hr each. I with the mild stock TBI truck cam even with those heads, I ran out of engine before I ran out of fuel even with the blower on it. At a 0.5 bsfc with 2 injectors that is fuel for 500 HP. If one was to run two of the 2" bore 454/Marine TBI units on the same engine with the EBL and the added injector driver you could run two of the TBI units on a blower and support closer to 1,000 hp.
The Mercury 575SCI was a factory supercharged, twin TBI big block that made good power/torque for an engine built for durability. There is a company that converts them to 8-71 blowers.
http://www.dyersblowers.com/187/1676.html
This is an example of the regulator I am talking about. I used the Vortec Super FMU on that setup.
http://www.ebay.com/itm/Vortech-Supe...tZb-Ib&vxp=mtr
A 61# high pressure 350 injector is about 105 lb/hr @ 32 psi in the 454/502 Marine throttle bodies. Running at 50 PSI they flow roughly 125 lb/hr each. I with the mild stock TBI truck cam even with those heads, I ran out of engine before I ran out of fuel even with the blower on it. At a 0.5 bsfc with 2 injectors that is fuel for 500 HP. If one was to run two of the 2" bore 454/Marine TBI units on the same engine with the EBL and the added injector driver you could run two of the TBI units on a blower and support closer to 1,000 hp.
The Mercury 575SCI was a factory supercharged, twin TBI big block that made good power/torque for an engine built for durability. There is a company that converts them to 8-71 blowers.
http://www.dyersblowers.com/187/1676.html
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Re: High pressure injectors on a TBI
Boosted, when I had a Marine 502 TBI on a Weiand 177 on Dart Iron Eagle 230cc heads on a 350 TBI in my 1983 G20 van.
This is an example of the regulator I am talking about. I used the Vortec Super FMU on that setup.
http://www.ebay.com/itm/Vortech-Supe...tZb-Ib&vxp=mtr
A 61# high pressure 350 injector is about 105 lb/hr @ 32 psi in the 454/502 Marine throttle bodies. Running at 50 PSI they flow roughly 125 lb/hr each. I with the mild stock TBI truck cam even with those heads, I ran out of engine before I ran out of fuel even with the blower on it. At a 0.5 bsfc with 2 injectors that is fuel for 500 HP. If one was to run two of the 2" bore 454/Marine TBI units on the same engine with the EBL and the added injector driver you could run two of the TBI units on a blower and support closer to 1,000 hp.
The Mercury 575SCI was a factory supercharged, twin TBI big block that made good power/torque for an engine built for durability. There is a company that converts them to 8-71 blowers.
http://www.dyersblowers.com/187/1676.html
This is an example of the regulator I am talking about. I used the Vortec Super FMU on that setup.
http://www.ebay.com/itm/Vortech-Supe...tZb-Ib&vxp=mtr
A 61# high pressure 350 injector is about 105 lb/hr @ 32 psi in the 454/502 Marine throttle bodies. Running at 50 PSI they flow roughly 125 lb/hr each. I with the mild stock TBI truck cam even with those heads, I ran out of engine before I ran out of fuel even with the blower on it. At a 0.5 bsfc with 2 injectors that is fuel for 500 HP. If one was to run two of the 2" bore 454/Marine TBI units on the same engine with the EBL and the added injector driver you could run two of the TBI units on a blower and support closer to 1,000 hp.
The Mercury 575SCI was a factory supercharged, twin TBI big block that made good power/torque for an engine built for durability. There is a company that converts them to 8-71 blowers.
http://www.dyersblowers.com/187/1676.html
Im sure being a draw-through supercharged setup helps a ton. Boost regulation of fuel would help you achieve those results. If it were a blow through, then you might've had an issue keeping up with fuel. Smart approach on your behalf
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Re: High pressure injectors on a TBI
Blow-through might have been more of an issue but honestly speaking its pressure differential across the injector you are looking to achieve. I know of someone that tested the TBi injectors at 80 PSI and although they became a little non-linear at that point they would still fire and pulse normally. With say 20 psi of boost on the nozzle end I am sure they would still open at 90 psi fuel pressure. The difficulty with pressurized TBI is the fact the throttle shafts will leak and often kill the TPS.