burnoutstang
Well-known member
Then is an external fuel regulator like the mallory even needed?
Carb Question
- Thread starter burnoutstang
- Start date
Please ignore that engine wrecking set up Wallaka put up. Six's have a fuel distribution problem. You fix it by putting an injector at each port. V8 guys have been modifying their manifolds for 25 years by drilling, welding or epoxy injector bungs in. Just use a throttle valve off of one of the late model cars. I think the Mustang's are pretty good sized. Some of the Chrysler stuff looks adequate. Just make a tapered adapter to the log 1 3/4" opening which I'm sure could also be opened up some.
A boost reference external regulator is necessary so your fuel pressure maintains 43 lbs above manifold pressure.
A boost reference external regulator is necessary so your fuel pressure maintains 43 lbs above manifold pressure.
350kmileford
Well-known member
Throttle valve? You mean throttle body? We basically need one, matched with a tps, iat, and map sensor? I'll look again, but I know we need a few sensors . .
burnoutstang
Well-known member
So are there any other units similar to the tempo (ie it all comes together in one package) that could meet the demands of a turbo? Is that what you mean by the gm alternative? And what would I search for to find one of these?
burnoutstang
Well-known member
And i think I'd prefer to stick with a efi instead of mefi just for the sake of simplicity.
How about something like this?
http://cgi.ebay.com/ebaymotors/87-95-CH ... dZViewItem
If something like this was setup on a 2bbl to 1bbl adapter then put on the intake, would that be rich enough for a boost application when needed, but still have a good idle? I would think that simplicity wise it makes sense. Use the ms to get it setup right and it would be good to go.
How about something like this?
http://cgi.ebay.com/ebaymotors/87-95-CH ... dZViewItem
If something like this was setup on a 2bbl to 1bbl adapter then put on the intake, would that be rich enough for a boost application when needed, but still have a good idle? I would think that simplicity wise it makes sense. Use the ms to get it setup right and it would be good to go.
350kmileford
Well-known member
If I knew how much those injectors flowed, I could tell you. Something tells me that 2 injectors will not be enough. . .
burnoutstang
Well-known member
But if you had two injectors flowing with high injectors wold that be enough? I mean if lincs200 could get it to work off a one-barrel carb, shouldn't that be enough to at least get the boost flowing up to say about 15psi?
OKay, now that you have figured out the basics, here is the deal:
There are two fundamental "flavors" of EFI. TBI and MPFI.
TBI (Throttle Body Injection) is usually simpler to set up and can be more cost effective. It is also less performance oriented and, as drag-200 states, suffers from all of the same fuel distribution problems as a carb.
Basically, think of TBI as an electronic carburetor.
MPFI (Multi Point Fuel Injection) allows you to inject fuel at each cylinder. This helps you in two fundamental ways: First, it helps solve fuel distribution issues alluded to by drag-200 by delivering fuel directly to each intake port, regardless of manifold design. Second, it can increase performance because it changes your manifold from a "wet" manifold to a "dry" manifold. This typically means that fuel is atomized better by the time it gets to the cylinder, where it actually matters. Essentially, fuel does not have time to fall out of suspension. With this in mind, your manifold can be designed without consideration for keeping fuel atomized and can again help compensate for non-ideal manifold designs.
TBI's only real advantage is it's simplicity - Frankly, that is a HUGE advantage. I do not suggest building a MPFI system from scratch for a de-virginizing EFI project (been there, done that - not for the faint of heart). Building a TBI system can be as simple as bolting a few things on and hooking up some wires.
So, drag-200's concerns aside, I would strongly suggest you build a TBI system. The fuel distribution and "engine killing" properties will be no worse than a carb - but you will gain all of the tuneability of EFI. I do not believe drag-200's concerns are especially worrisome for moderate boost levels and conservative (rich) WOT fuel maps. If you are going to build a motor on the ragged edge of performance, then it is certainly a paramount issue.
So, TBIs:
Much like carburetors, Trottle Bodys come in various configurations. Typically for TBI systems they will be described just like Carbs IE 1bbl, 2bbl, 4bbl.
A little aside on a Throttle Body. There are two basic types - those for TBI systems (Wet) and those for MPFI systems (Dry). The only real difference is TBI tb's include one or more injectors, and are designed with the atomization of fuel in mind. They tend to somewhat resemble carburetors.
All TB's (for the most part) incorporate some sort of throttle position sensor (TPS) and an Idle Air Control Valve (IAC).
The aftermarket offers several in each category and they are ungodly expensive. I do not suggest using an aftermarket TB in a TBI system. If you plan on the level of performance that requires one, then I suggest MPFI.
More about TBI:
There are many many OEM TB options out there. The Tempo one is popular here because of it's simplicity. It is a single barrel style TBI with one injector. It is popular because it nearly bolts to the stock carb opening and has an integral fuel pressure regulator. It is as close to a "bolt on" EFI option as I am aware exists. It's performance potential is limited however (by the single injector's flow capability as well as airflow restrictions) to not much beyond stock. Someone can give real numbers based on BSFC i'm sure. It is basically an EFI replacement for your stock 1bbl carb.
The TB that I would suggest however is the 2bbl GM TBI. This 2bbl style TBI came on everything from 2.8L V6's to SS 454's. Equipped with 454 sized injectors, this TB can support approximately 300 horsepower.
It includes a TPS and IAC, but not FPR (fuel pressure regulator). As stated above, it is a 2bbl style TBI that is loosely based around the holley 2300 style flange. It is reasonable to conclude that an intake designed (or modified for) a holley 2bbl could be easily modified to accept the GM TBI.
It looks like this:
The use of this TBI will require (at a minimum) the following things:
1.) The TBI it's self.
2.) A computer controller, like Megasquirt
3.) A EFI fuel pump. TBI runs at (IIRC) ~ 13 psi. (http://fordsix.com/forum/viewtopic.php?t=49473)
4.) A quality AFPR (adjustable fuel pressure regulator). Especially important with boost.
5.) A MAP (Manifold Absolute Pressure, otherwise known as load) sensor. The Megasquirt includes this for you.
With those 5 things properly installed and interconnected one could get this TBI up and running. Increased functionality (Spark Control, for example) would require additional parts - but none of which is prohibitively expensive or complicated - and each can be added down the road as your motivation dictates.
The hardest part of any EFI system is tuning. The process is not in and of itself difficult, but it can be tedious and always takes patience and time. It will not be a bolt on and go type of setup - but then again, neither is a carb. (Despite what many people seem to think)
As a reference, I built a MPFI system for my camaro out of stock parts I purchased off ebay and craigslist. This was before megasquirt hit the big time, so to speak, so I used a stock computer that I reprogrammed via flash EEPROM.
It took me a year to collect the parts (on a college budget) and a week to install them.
Tuning it to the point that it could be driven took about two days. Getting it to the point that it drove really well took a few weeks.
That was my first time with a much more complicated system. I am confident that you could do much better with a simple TBI setup.
I believe the GM TBI will be the next upgrade to my car. I just need to tell the old lady to stop getting cavities and then I can actually afford the parts
[/url]
There are two fundamental "flavors" of EFI. TBI and MPFI.
TBI (Throttle Body Injection) is usually simpler to set up and can be more cost effective. It is also less performance oriented and, as drag-200 states, suffers from all of the same fuel distribution problems as a carb.
Basically, think of TBI as an electronic carburetor.
MPFI (Multi Point Fuel Injection) allows you to inject fuel at each cylinder. This helps you in two fundamental ways: First, it helps solve fuel distribution issues alluded to by drag-200 by delivering fuel directly to each intake port, regardless of manifold design. Second, it can increase performance because it changes your manifold from a "wet" manifold to a "dry" manifold. This typically means that fuel is atomized better by the time it gets to the cylinder, where it actually matters. Essentially, fuel does not have time to fall out of suspension. With this in mind, your manifold can be designed without consideration for keeping fuel atomized and can again help compensate for non-ideal manifold designs.
TBI's only real advantage is it's simplicity - Frankly, that is a HUGE advantage. I do not suggest building a MPFI system from scratch for a de-virginizing EFI project (been there, done that - not for the faint of heart). Building a TBI system can be as simple as bolting a few things on and hooking up some wires.
So, drag-200's concerns aside, I would strongly suggest you build a TBI system. The fuel distribution and "engine killing" properties will be no worse than a carb - but you will gain all of the tuneability of EFI. I do not believe drag-200's concerns are especially worrisome for moderate boost levels and conservative (rich) WOT fuel maps. If you are going to build a motor on the ragged edge of performance, then it is certainly a paramount issue.
So, TBIs:
Much like carburetors, Trottle Bodys come in various configurations. Typically for TBI systems they will be described just like Carbs IE 1bbl, 2bbl, 4bbl.
A little aside on a Throttle Body. There are two basic types - those for TBI systems (Wet) and those for MPFI systems (Dry). The only real difference is TBI tb's include one or more injectors, and are designed with the atomization of fuel in mind. They tend to somewhat resemble carburetors.
All TB's (for the most part) incorporate some sort of throttle position sensor (TPS) and an Idle Air Control Valve (IAC).
The aftermarket offers several in each category and they are ungodly expensive. I do not suggest using an aftermarket TB in a TBI system. If you plan on the level of performance that requires one, then I suggest MPFI.
More about TBI:
There are many many OEM TB options out there. The Tempo one is popular here because of it's simplicity. It is a single barrel style TBI with one injector. It is popular because it nearly bolts to the stock carb opening and has an integral fuel pressure regulator. It is as close to a "bolt on" EFI option as I am aware exists. It's performance potential is limited however (by the single injector's flow capability as well as airflow restrictions) to not much beyond stock. Someone can give real numbers based on BSFC i'm sure. It is basically an EFI replacement for your stock 1bbl carb.
The TB that I would suggest however is the 2bbl GM TBI. This 2bbl style TBI came on everything from 2.8L V6's to SS 454's. Equipped with 454 sized injectors, this TB can support approximately 300 horsepower.
It includes a TPS and IAC, but not FPR (fuel pressure regulator). As stated above, it is a 2bbl style TBI that is loosely based around the holley 2300 style flange. It is reasonable to conclude that an intake designed (or modified for) a holley 2bbl could be easily modified to accept the GM TBI.
It looks like this:
The use of this TBI will require (at a minimum) the following things:
1.) The TBI it's self.
2.) A computer controller, like Megasquirt
3.) A EFI fuel pump. TBI runs at (IIRC) ~ 13 psi. (http://fordsix.com/forum/viewtopic.php?t=49473)
4.) A quality AFPR (adjustable fuel pressure regulator). Especially important with boost.
5.) A MAP (Manifold Absolute Pressure, otherwise known as load) sensor. The Megasquirt includes this for you.
With those 5 things properly installed and interconnected one could get this TBI up and running. Increased functionality (Spark Control, for example) would require additional parts - but none of which is prohibitively expensive or complicated - and each can be added down the road as your motivation dictates.
The hardest part of any EFI system is tuning. The process is not in and of itself difficult, but it can be tedious and always takes patience and time. It will not be a bolt on and go type of setup - but then again, neither is a carb. (Despite what many people seem to think)
As a reference, I built a MPFI system for my camaro out of stock parts I purchased off ebay and craigslist. This was before megasquirt hit the big time, so to speak, so I used a stock computer that I reprogrammed via flash EEPROM.
It took me a year to collect the parts (on a college budget) and a week to install them.
Tuning it to the point that it could be driven took about two days. Getting it to the point that it drove really well took a few weeks.
That was my first time with a much more complicated system. I am confident that you could do much better with a simple TBI setup.
I believe the GM TBI will be the next upgrade to my car. I just need to tell the old lady to stop getting cavities and then I can actually afford the parts
[/url]
burnoutstang
Well-known member
Brilliant Post!!! 
That along with an article I found
http://www.302w.com/Windsor_MegaSquirt_ ... ction.aspx
gave me the info I needed.
I'm going to begin looking for that style of tbi and order the megasquirt. I figure I'll get the efi running and then add in the complications of a turbo. I also plan to chronicle the entire process with pictures and a running cost list. Wish me luck...
That along with an article I found
http://www.302w.com/Windsor_MegaSquirt_ ... ction.aspx
gave me the info I needed.
I'm going to begin looking for that style of tbi and order the megasquirt. I figure I'll get the efi running and then add in the complications of a turbo. I also plan to chronicle the entire process with pictures and a running cost list. Wish me luck...
burnoutstang
Well-known member
Another question, could the tbi be placed atop a carb adapter, or would it need to be direct milled?
burnoutstang
Well-known member
So for those who have had a head direct milled, how much did it cost to have it done so i can get an idea to take to the shop?
burnoutstang
Well-known member
How? burnoutstang":pqzd576j said:
Very carefully.
In actuality, it took a couple of hours one afternoon.
Cut, grind, sand, - shop vac is your friend to keep grit out of the motor. Paper towels stuffed up the intake log help a lot too. A belt sander helps to achieve a roughly level surface if used properly.
Make carb flange and then bolt to head - seal w/ Epoxy. Seems to work fine, but I've been lazy about finishing up my cable throttle so I haven't driven it.
burnoutstang
Well-known member
What kind of saw/saw blade/hole cutter/tool thingy works to make that big of a hole? I have a dremel so grinding isn't a problem. Same deal with the belt sander.
burnoutstang
Well-known member
Anybody?
350kmileford
Well-known member
A Dremel wouldn't be enough. Do you have a (large) air compressor at your disposal? I would recommend a die grinder.
burnoutstang":159qye1e said:
The Chrysler K cars & cloud cars (sundance, cirrus) had TBI units (I've got one I plan on using) and they even used some of them for turbo applications (Dodge Daytonas) in the late 80's & early 90's. They can be had for next to nothing. I got one off Fleabay for $40 including shipping. You local slavage yard is bound to have some...
Check out Hot Rod magazine online or look for the thread here where they blew up the 6 cyl Maverick (bye bye lil buddy) and you can see that's what they used to first put FI on it.
