TBI VS TPI
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Car: 1988 Chevy silverado K5
Engine: 350 bored .030, crane cams hyd bluprint l-79 cam 447 lift 272 dur, camel hump heads port and polished 1.94 1.50, afterburner headers and y pipe, holley 670 cfm tbi, holley projection dual plane manifold, accel high pressure fuel pump, 3 inch exhaust
Transmission: 700 r4 with corvette servo and shift kit.
TBI VS TPI
Whats the pros and cons of each system? I'm still in the planning phase of my build and already have a tbi setup capable of 400 plus hp but its seems like tpi supports more power from what I've heard and makes more tq and hp because of the better atomization and intake design.
I'll be posting this in the tpi thread too to get both sides of the story.
I just thought about it last night... why put all this money into a tbi system when a tpi system can do it better and handle more power? Or can it? I don't know much about the tpi setup... Thats why I'm posting this.
I'll probably end up starving my motor if I stay with tbi... my old plan was hyd flat tappet lifters and afr's older street heads but I'm planning on a 383 with afr eliminator 195 street heads(has to stay CA smog legal), roller rockers, and mechanical flat tappet lifter so I'll be somewhere around 450-475 hp and 520 or so ft lbs N/A at least thats what desktop dyno says.
I think tpi would be the only option for that but then again you guys know your shiznat when it comes to tbi...
School me.
I'll be posting this in the tpi thread too to get both sides of the story.
I just thought about it last night... why put all this money into a tbi system when a tpi system can do it better and handle more power? Or can it? I don't know much about the tpi setup... Thats why I'm posting this.
I'll probably end up starving my motor if I stay with tbi... my old plan was hyd flat tappet lifters and afr's older street heads but I'm planning on a 383 with afr eliminator 195 street heads(has to stay CA smog legal), roller rockers, and mechanical flat tappet lifter so I'll be somewhere around 450-475 hp and 520 or so ft lbs N/A at least thats what desktop dyno says.
I think tpi would be the only option for that but then again you guys know your shiznat when it comes to tbi...
School me.
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Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
You will need an aftermarket intake for TPI to make the power you want. TPI starts to choke a STOCK L98 around 4,200 RPM or so.
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Car: 1988 Chevy silverado K5
Engine: 350 bored .030, crane cams hyd bluprint l-79 cam 447 lift 272 dur, camel hump heads port and polished 1.94 1.50, afterburner headers and y pipe, holley 670 cfm tbi, holley projection dual plane manifold, accel high pressure fuel pump, 3 inch exhaust
Transmission: 700 r4 with corvette servo and shift kit.
how about the throttle body? is 475 ish(being generous) hp doable for tpi?
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Car: check
Engine: check
Transmission: check
Blazin, a TBI setup will work with what you are planning. As for staying Cali smog compliant, an EGR is the catch. A decent single plane manifold with EGR is a good choice. A BBC TBI unit with 81 lb/hr injectors at 30 psi will support 475 HP on a 383.
Part of that statement is because a 383 will make that HP at low RPMs, such as 5,800 RPM. So injector DC% can be pushed a little (there is more to injector open/close time then DC%). Run an external fuel pressure regulator vacuum referenced and it will be a great running setup.
I too am in the process of building a 383. It will be TBI. Which I wouldn't even attempt without an EBL setup (If you know of a good source for the AFR heads {1038's}, please PM me).
RBob.
Part of that statement is because a 383 will make that HP at low RPMs, such as 5,800 RPM. So injector DC% can be pushed a little (there is more to injector open/close time then DC%). Run an external fuel pressure regulator vacuum referenced and it will be a great running setup.
I too am in the process of building a 383. It will be TBI. Which I wouldn't even attempt without an EBL setup (If you know of a good source for the AFR heads {1038's}, please PM me).
RBob.
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Car: 91 RS
Engine: 305
Transmission: T5
Axle/Gears: 3.73
#9
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Car: 1988 Chevy silverado K5
Engine: 350 bored .030, crane cams hyd bluprint l-79 cam 447 lift 272 dur, camel hump heads port and polished 1.94 1.50, afterburner headers and y pipe, holley 670 cfm tbi, holley projection dual plane manifold, accel high pressure fuel pump, 3 inch exhaust
Transmission: 700 r4 with corvette servo and shift kit.
Thats what I was hoping to hear and yes the ebl will be a major priority in my build... compliments to you rrob that is some cool shiznat.
But I have a holley 670 with 85 pph injectors... is 30 psi still ok?
But I have a holley 670 with 85 pph injectors... is 30 psi still ok?
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Car: check
Engine: check
Transmission: check
My understanding is that the new(er) units with the Delphi injectors (right angle connector) will take that kind of pressure. I was working with someone that was using that unit and we had no problems with 30 psi. Others have said the same about the Delphi's, they can take a lot of pressure.
RBob.
RBob.
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