What it takes to run turbo's on a carb

[Turbo455]

I get many questions about what does it take to run turbo's through a carburetor. So I have composed a list of Item's that I would use to turbo any Carbureted car in the future. Note that not all of these parts are required this is just the easiest way that I know to make the tuning easy.

1. 65 psi 450 lbs/hr 8an in and 6an out $210 http://www.summitracing.com/parts/SUM-G3137/

2. Bypass regulator $68 http://www.summitracing.com/parts/hly-12-803bp/

3. Boost reference conversion kit $10 http://www.summitracing.com/parts/RPU-5006/

4. Instead of parts 2+3 you can use http://www.summitracing.com/parts/aei-13301/

5. Blow threw Demon Carb 850 for the 455 for $600 Ebay seller richdesbiens

6. Wide band AFR gauge kit $200 http://www.summitracing.com/parts/AVM-30-4223/

7. Carb jet kit $50 http://www.summitracing.com/parts/hly-36-181/

8. Jet tool $10 http://www.summitracing.com/parts/mor-62293/

9. Water/Alcohol Injector $375 http://www.alcohol-injection.com/dvc...age-2-305.html

10. And of course one of Burton Machines Turbo Kits $1995 Call 509-860-3370 ask for Mark. Do not be afraid to call mark, he is very helpful.

Items 4,5,6,7,8,9 are not required


1. The fuel pump needs to be mounted no higher than the lowest point of the gas tank. I would suggest that you put a bung on the bottom at the back of the tank and mount the fuel pump right there. The pump must be able to pump 6psi + what ever amount of boost you will be making. So if you are going to be running 9psi then you need a pump that will push at least 15 psi. It is better to go to big than to small.

2. You may need to put in larger fuel lines. I ran 1/2" but 3/8" will be fine with this pump. I think you could even get away with 5/16"(Stock).

3. Next you need a Bypass style regulator. You may get the one that has the boost reference port built into the regulator part no. 4 or you may replace the adjustment bolt with part no. 3 this will convert a standard bypass style to a boost reference bypass. you will then need to run a vacuum line from the port to the carb hat. You must have a return line that goes from the regulator back to the tank.

4. You may opt out of purchasing a Blow thru Demon carb and just modify your carb to take the boost. I prefer not to go that route, I just purchase a Demon Blow thru carb, no fuss no muss.

5. You many get lucky and your car will run just fine with stock jets. I doubt it. I would just get the jet kit. You will need the tool as well because if you don't you will just screw up the jets.

6. Remember, going lean is what usually kills the pistons. Next I would install a Wideband AFR gauge. This is not a requirement but it will be a lot easier to tune. Once I put my Wideband in it took 5 or 6 pulls down my street to get the AFR correct by swapping out bigger and bigger and bigger jets. I had to go up 10 sizes.

7. All turbo's heat the intake charge, so some sort of inter cooling will help you to produce more power. It will also allow you to run more boost without killing the pistions. I choose to run a chemical inter cooler (water/alcohol injector). This not only cools the intake charge but it also increases the octane of the fuel. If you are going to run 6psi or less this will not be required. However you will benefit from a cooler intake charge.

8. Bolt on Burton Machine Turbo Kit and run a hose from the carb hat to the bottom port of the waste gates. You will also need to put a 1/4" T fitting in the oil pressure line to fee oil to the top of the turbo's then you will need a large(3/4" ID) hose coming from the bottom of the turbo to the oil pan. You must use a large line because the turbo will froth the oil. I just welded in bungs on the side at the very front of the pan. Make sure that these return lines have a straight path to the oil pan.

9. Pull your timing all the way down to 2-4* initial timing. Get your AFR correct (11.5-12.5) before Moving the timing up. You may increase the timing 1* at a time. If you hear pinging back off the gas as fast as you can, recheck AFR and possibly take more timing out. With a turbo car you need a much smaller advance curve than normal. You may even want to lock the timing at something in the range of 28*. I clamped a camera to my steering column to record the AFR and Boost reading for playback for tuning. You may also have someone ride with you to let you know if the AFR is getting dangerously low. The second method is probably the safest. If you are not in the safe range(11.5-12.5) you might as well just let off the gas and install larger jets.

10. As far as cam's go the less overlap you have the less of a chance you have of your exhaust contaminating the intake charge, this is also called reversion. This happens when the intake and exhaust valves are opened at the same time and the exhaust pressure is more than the intake pressure. The other thing to think of is the lobe separation. the lower the separation the more overlap you will have. But if you go to a higher separation like a 114 the more cylinder pressure it will bleed off at the beginning of the compression stroke. But this shouldn't matter because your boost will compensate for that. All of this mumble jumble means that if you keep your duration around 220 @.05 and the LSA at 114 and install it 4* advanced you should be fine. My cam is @ .050 223int/218ex 114 LSA with .480/.480 lift. Crower is the only cam I have found that is specifically designed for turbo app. Call Crower at 619-661-6477 and they will help you get a cam for your application. A stock cam will work much better than a blower style cam.

11 Enjoy your 600+hp that idles like it is just a stock 150hp sbc. Can you say sleeper. I wish you guys could hear my car in person. I have had a lot of people say that it sounds like a stock small block.


WARNING !!!!!!!!!
If you drive yours on the street be warned that the massive torque that the turbo makes when it spools will over power the tires at very low RPM's. Mine has caught me off guard several times. It usually goes something like this: I need to just speed up a little to merge or switch lanes and so I press the gas just a little and it builds boost and shifts gears at the same time and breaks the tires loose. Once on a merge the car went sideways at about 1/4 throttle. Another time I was switching lanes at low speeds in town trying to make it to my next turn and almost hit the sidewalk. Although this sounds like a good problem to have just keep this in mind if you decide to let someone else drive your car. As a matter of fact the only place I will let anyone drive my car is at the race track in a straight line.

[yacster]

Please Make this a Sticky!!!!!!!!!!!!!!!
I hate having to search for this stuff over and over... Thank you for your efforts James. Any additional info concerning your cam should be added to the thread, it would be so nice to have everything you did and learned in one place

[Turbo455]

Please Make this a Sticky!!!!!!!!!!!!!!!
I hate having to search for this stuff over and over... Thank you for your efforts James. Any additional info concerning your cam should be added to the thread, it would be so nice to have everything you did and learned in one place

Thanks Anthony,
I added some info about cams. I don't know how to make this a sticky. I think that the moderator has to do that. I will add any updates or new findings to the original post number 1

[Justa350]

Great thread James! Lots of good first hand info, not just the "read somewhere" "heard once" online junk that is all over the place. Really shows how simple it can be.

[Turbo455]

Great thread James! Lots of good first hand info, not just the "read somewhere" "heard once" online junk that is all over the place. Really shows how simple it can be.

Mark I added your phone number to kit info. I hope that's OK.

[Justa350]

Yep, it's in my sig too so no problem.

[Turbo455]

I have been doing some research for Jay3000 project so that I could recommend a cheaper pump then the one in the first post in this thread. And here is a formula to figure out what pump will work. Fuel flow is very important. An NA motor will need .5 gph a turbo motor will need .6 gph so a gallon of fuel weighs 6 pounds so an NA motor will need .5/6=.0833 or turbo is .6/6=.1000 so if you want to make 500hp at 9psi of boost you will need 500/.1=50 gph or 50*6=300 pph and this pump will need to have at least 9psi boost + 6psi base + 5psi reserve=21psi pump You may get away with NA usage on a turbo motor but I wouldn't plan for it. So the pump I recommend is good to 750hp(trubo) or 900(NA)

[Nothingface5384]

what do you think about the fuellab 1800hp epump?
http://www.fuelab.com/index.php?page...emart&Itemid=3

sounds like you dont even need a fuel/boost regulator as its builtin
also all the ports are 10AN

a2000 kit doesnt seem bad either as it comes with a fuel regulator(not sure if its boost referenced) and its a tad cheaper...theres also a univeral kit for 900 which includes lines and fittings but not sure if thats a deal or not..havent prices lines yet

[Turbo455]

what do you think about the fuellab 1800hp epump?
http://www.fuelab.com/index.php?page...emart&Itemid=3

Looks like a very good pump and will definitely handle what every any of us are going to do.

[Nothingface5384]

bump for link above

I'm ready to order one soon and want to double check that'll it'll suit 10 to possiblt 15psi down the road
I know it states 1800hp carb but it also says @ 20psi..

Wouldnt I need more then that, if s i guess i'll have to go with one of their efi version pumps?

http://www.fuelab.com/index.php?page...emart&Itemid=3

[sailbrd]

Things I have found out.
1. Fuel pressure guage. First you MUST know your fuel pressure. Loss of pressure=loss of motor. You will find that the fuel pressure guage will tell you how much boost you are making above the carb. Lets say you see 7 psi at idle. If the fuel pressure guage goes to 15psi then you are making 8psi above the carb. I really like RobbMc regulator.
2. Return line is really important. I run -8 to the regulator -10 back.
3. 100 micron prefilter. Do not use anything smaller (ex 40 micron)
4. So far I am very pleased with my QuickFuel carb. Bobb M got one for me for less than $600. They come a little fat but good place to start. I am running a 650BAN that made 630 HP on Anthoneys 370 SBB.
5. AFR guage. Not really an option. This is a different ball game. Whatever you know about carbs is now changed. Right now I know I run 10.5 WOT so I can start taking fuel out of it. Going to the track and trying to use the old tuning methods? OPPS too lean... good bye piston.

[TaxBBBuick]

Hi guys, I new to the site. I have been wanted to turbo my car so I went to turbobuick.com and the are convincing me that i should just do a camm job. the amount of money that i want to spend (3k) is no where near enough to turbo it.

How much was your overall project. Im not looking for as much HP as you.

thanks,

Tax

[sailbrd]

Hi guys, I new to the site. I have been wanted to turbo my car so I went to turbobuick.com and the are convincing me that i should just do a camm job. the amount of money that i want to spend (3k) is no where near enough to turbo it.

How much was your overall project. Im not looking for as much HP as you.

thanks,

Tax

What car, what motor etc. Also give the topic its own post in high tech for old iron

[Nothingface5384]

hey, what filter combo would you guys think would be best

summit inline billet fuel filter 100 micron ss pre filter and 10 micron celleous filter


or

fuelab 75 micron ss prefilter with 10 micron celleous filter?

the summit is cheaper buy like a good 60 bucks but not sure how well they're made

[BRUCE ROE]

11 Enjoy your 600+hp that idles like it is just a stock 150hp sbc. Can you say sleeper. I wish you guys could hear my car in person. I have had a lot of people say that it sounds like a stock small block.

WARNING !!!!!!!!!
If you drive yours on the street be warned that the massive torque that the turbo makes when it spools will over power the tires at very low RPM's. Mine has caught me off guard several times. It usually goes something like this: I need to just speed up a little to merge or switch lanes and so I press the gas just a little and it builds boost and shifts gears at the same time and breaks the tires loose. Once on a merge the car went sideways at about 1/4 throttle. Another time I was switching lanes at low speeds in town trying to make it to my next turn and almost hit the sidewalk.

Has happened to me. One instant nothing, next instant tires broken loose. Seems to me, it would be better if the max torque/boost were limited by the
throttle position. That could be done with a control from the throttle position sensor, to the waste gate. Why not? Bruce Roe

[sean Buick 76]

WARNING !!!!!!!!!
If you drive yours on the street be warned that the massive torque that the turbo makes when it spools will over power the tires at very low RPM's. Mine has caught me off guard several times. It usually goes something like this: I need to just speed up a little to merge or switch lanes and so I press the gas just a little and it builds boost and shifts gears at the same time and breaks the tires loose. Once on a merge the car went sideways at about 1/4 throttle. Another time I was switching lanes at low speeds in town trying to make it to my next turn and almost hit the sidewalk. Although this sounds like a good problem to have just keep this in mind if you decide to let someone else drive your car. As a matter of fact the only place I will let anyone drive my car is at the race track in a straight line.

Since I am using a manual valvebody on my th400 I will be in control of the shifts which should help. I can not wait to leave the line at 3200 RPM off the trans brake with the turbos spooled up!

[jay3000]

Has happened to me. One instant nothing, next instant tires broken loose. Seems to me, it would be better if the max torque/boost were limited by the
throttle position. That could be done with a control from the throttle position sensor, to the waste gate. Why not? Bruce Roe

That sounds difficult, complicated, and not necessary.. The TWO waste gates are pressure activated. No way to do that with a lever.. Just run some sticky tires.. Throttle position sensor??? Come on..

[BRUCE ROE]

That sounds difficult, complicated, and
not necessary.. The TWO waste gates are pressure activated. No
way to do that with a lever.. Just run some sticky tires.. Throttle
position sensor??? Come on..

Might not be necessary for the track. But to me the beauty of a turbo,
is the ability to make a huge amount of power with a relatively
ordinary, completely streetable engine. Sticky tires are useless on
my gravel road, or in the rain. You are welcome to deal with difficult
to control torque, but I choose not too. It doesn't appear at all
difficult to do, compared to all the engine stuff on cars these days.
If I ever have another turbo system, I'll need to work on this.

Bruce Roe

[Justa350]

I think a TP sensor based boost controller is an awesome idea. Low boost at part throttle cruise and big power when you want it.

[pmuller9]

I think a TP sensor based boost controller is an awesome idea. Low boost at part throttle cruise and big power when you want it.

You can put one together without much trouble.

The minimum boost pressure is determined by the spring in the wastegate.
You can check your minimum boost level by disconnecting the air line from the boost controller and running the car.
It is important that you leave the wastegate port that was connected to the controller OPEN (not plugged) during the test.
We want a spring that barely allows any boost or near 0 manifold pressure.

The manifold pressure will track the air pressure controlling the wastegates and it is not necessary to control boost using manifold pressure feedback.
We use a MSD boost controller as a pressure regulator to the wastegates and the manifold pressure tracks the regulated air perfectly.
The difference between the air pressure to the wastegates and the manifold pressure is determined by the wastegate spring so if the spring pressure is very low
the boost pressure will be close to the regulated pressure to the wastegate.

An Electro-Pneumatic Transducer converts a voltage or current signal from an electronic controller into a pneumatic output pressure signal.
An increase or decrease in the input signal proportionally increases or decreases (respectively) the output pressure.
They can be controlled with variable voltage in the range around 0-10 volts or 4 - 20 ma.

You will also need a constant air pressure source of around 20 psi. A small electric pump or a mechanical pump converted from the old mechanical fuel pump.

Attach a TPS to the throttle and make an interface to supply the voltage or current range needed to control the EPT.

What do you think?

Paul

[BRUCE ROE]

You can put one together without much trouble.
+++++++++++
We use a MSD boost controller as a pressure regulator to the wastegates and the manifold pressure tracks the regulated air perfectly.
++++++++++++
Attach a TPS to the throttle and make an interface to supply the voltage or current range needed to control the EPT.
++
Paul

Do you have some drawings? Bruce Roe

[pmuller9]

Do you have some drawings? Bruce Roe

Bruce

I will put a drawing together for you.

Paul

[alan]

I feed the boost signal to the pressure side of the wastegates, and through a regulator to the vacuum side of the wastegates. The wastegates have 4psi springs in them, so setting the regulator to 4psi results in 8psi boost. Setting the regulator to 8psi would result in 12psi boost. I plan to install an electric valve that will vent the vacuum port on the wastegates to atmosphere until the throttle is wide open (small electric switch), at which time the valve will then connect the vacuum port to the regulator and increase the boost to whatever you set it to.

4psi boost max until you floor it.

[pmuller9]

I feed the boost signal to the pressure side of the wastegates, and through a regulator to the vacuum side of the wastegates. The wastegates have 4psi springs in them, so setting the regulator to 4psi results in 8psi boost. Setting the regulator to 8psi would result in 12psi boost. I plan to install an electric valve that will vent the vacuum port on the wastegates to atmosphere until the throttle is wide open (small electric switch), at which time the valve will then connect the vacuum port to the regulator and increase the boost to whatever you set it to.

4psi boost max until you floor it.

That's what I'm talking about!

Alan, Nice solution

The scheme I presented is nothing more than taking your solution and adding a variable regulator that operates off the TPS to vary max boost between no throttle and WOT.

Thanks for your input

What are you using for a boost controller?

Paul

[alan]

What are you using for a boost controller?

For now, 2 Turbonetics race gates and 1 low pressure (10 or 15 psi max, I forget which!) pnumatic regulator.