[DylanZ]

I don't know if anny of you were reading the post a day or two back, but it was about wheather or not 510's handle as well as z's, anyways, there was a link to Paddy510's cite in there:

http://www.geocities.com/paddy510/

And he has a cool draw thru turbo setup. I have always thought that this would be an awesome and cheap way to do a turbo, and was wondering if anyone has seen or done this on an L28??

 

[zx-ae]

I've been thinking about how to se one of those up since I seen his post. I think its pretty feaking cool.

Here my idea got from the picture

Pull all the FI stuff off the car, plug all the holes left from the FI stuff and leave everything else the way it was before but with out the TB(maybe you could just leave it wide open or take out the butterfly valve) and AFM. Get some kind of carb(s)(anykind really) and weld a fitting (to bolt the carb to) at the end of some pipeing then conect it to the turbo input. then set up some kind of trottle cable to hook to the carb(s).

What do ya think would it work?? what are the any problems with a system setp like that?? would the air and fuel stay mixed(atomized??) well enough after going all that way?

Well its sounds good to me anyway.
Justin T

 

[DylanZ]

You's still need a turbo exhaust manifold, but it should work. The fuel/air mixture should be well atomized after getting run through a turbo and heated by it. I think a person would be better off making a custom intake manifold, just to simplify things. I don't think you can run much boost at all, or an intercooler, for the simple fact that if there was ever a backfire, you would have several litres of compressed fuel/air going bang. Heck, if you run an intercooler around the front, you'd have a huge bomb on hand. I think that the shorter the intake tract, the better. Mabee a person could set it up as a twin turbo. A couple of little k-car turbos (cheap and plentiful) each with their own bank of three cylinders, feeding 2 intakes. It could be made with a couple of build your own header kits and some enginuity. I've seen a big block v-8 that was done like this off of propane, no carb. The thing looked terrible as it was built with 2" square tube bent with a torch and a vice, and bird sheited together. but ****, it went fast in an old camaro.

 

[zx-ae]

I was thinking of motor with the turbo/manifold already installed. So you think it would be better build a custom manifold? I figured it would, but I was thinking of a low cost solution. It would since you could put the pipe from the turbo outlet right to the closest place on the manifold and not have to go all the way around to the front. And I agree with you on the intercooler thing, BOOM.

I was also pondering a tiwn turbo setup similar to your idea. Get a header hack the pipes off of it route some piping to two turbo flanges, get two turbos, twocarbs(overkill?) and have them run into two intake manifolds(or would it be better to have them both run into one big one?).

And I have a 3rd idea but its not draw through. not sure if this would work or not seems like it would bring too much air into the system. Instead of putting the carb at the begining of the system, bolt it on the intake manifold and have the turbo system piping as it normaly is. Well after I think about it all the compressed air would just come out of the intake on the carb(right?) so that wont work. Nevermind, I just brainstorm that idea anyway.

Wouldnt a draw through carb system be hard to start?

Justin T

 

[paddy510]

a pic & some ideas, (LONG)

g`day,
theres some pics of a 240z with a suckthru turbo setup on the OZDAT website under feature cars.

a cheap way to set it up would be to use the factory turb mani and the SU mani, make up a Y pipe to join the SU mani to the turbo and make up an adapter to bolt a 350/500holley to the turb. or you could just use the SUs and make a Y pipe to mount them to the turbo, itd be easier to setup the throttle cable/linkages with the holley but id say the SUs would work better.

i dont know if any L6 motors came out over there with the downdraft carb or not but the manifold from these would be the cheapest(also ugliest) way to set it up as you only need to run a single pipe from the turb to where the carb mounted.

you could also make up an new inlet manifold if you want(somthing similar to mine) by using some 2.25" or 2.5" exhaust pipe as the plenum and some 1.5"(about 6" long) pipe for the runners, a bit of 2" pipe for an intake(placed so as to go as directly to the turbo as possible(the shorter the distance from carb to head the better)), get a flange plasma cut by copying the gasket shape and get it all TIG or MIG welded together, this way will look the best and probly work the best but it is more expensive, but if you know someone that can do this type of work then it can be done very cheap.

using 2 headgaskets on an otherwise std motor the comp ratio should be low enuff for around 7-10psi. the main prob with getting high hp from the suckthru setup is avoiding detonation/preignition since you cant(safely) use an intercooler. you could run water injection to help cool the charge but it does strange things to the metal in the L heads apparently.

i think it is a really good option for those that are on a tight budget. cheaper than getting the power from NA and a lot cheaper/easier than converting to efi. fuel economy should comparable to a mildly worked NA too
my 510 setup cost me around $1000AU(2.5" home made mandrel bend exhaust($160), 1.75" SU carb($35), RX-7 turbo and custom manifold($700), hoses/bolts/clamps etc etc(~$150).) i did all the work, except for make the manifold, myself which cuts the costs down a helluva lot.
sorry for typing so much i kinda got carried away there
Later
Paddy

 

[zx-ae]

Re: a pic & some ideas, (LONG)

I looked at that page and that is a crazy setup, If you were to put that kind of money into a motor why not just use FI?

Say I wanted to do a carb turbo setup, I have a turbo parts car. Icould grab the exhaust manifold and turbo off of it bolt it to my motor. Find me a dual SU manifold put a Y pipe on it run it to the output on my turbo. Get a peice of pipe weld a flange for a carb(probably a SU, but it would would be hard to tune that far down in the engone bay) and attach it to the turbo inlet. Pull my head and put two head gaskets on. And that would give me a pretty decent cheap turbo set up right?
Man that sounds way too easy am I missing something??

Justin T

 

[DylanZ]

Re: a pic & some ideas, (LONG)

This 240 on Ozdat is almost exactly what I was thinking of for a single turbo. Minus the carbs. There's no point in having two small ones on one large hole when you could simplify with one large, cheap and readilly availible used carb, as mentioned before, the holley. I just wonder where the [email protected] he got that fancy little adapter from to get the two carbs onto that turbo... But despite what ZX-AE thinks, I don't think this would have been verry expensive. I could build a monifold like that, no problem - somebody scratch built that one on the 240. The welds ar'nt even that nice. I have acess to such tools, and have a welder. I think I could do a conversion like this for not alot of dough. Just the cost of the turbo manifold and turbo, and the normal huge list of unforseen little cheap stuff that tag on to every mechanical endever, and a few spare parts. and the new exhaust (I need one anyway). I like it. But it would never have the potential of an injected turbo I wonder what kind of gain could be seen at a safe 6-8 lbs? mabee it's not even worth it. Mabee money could be better spent with an injected setup. I do like the simplicity of it all though. It would be fun to build. I wonder if it would be ok with flat-top pistons. I could probably wonder for hours and hours.

Dylan

 

[paddy510]

Re: a pic & some ideas, (LONG)

g`day,

in theory it is as easy as that, theres a few little bits n pieces that you have to do aswell, like tap in a oil feed for the turbo(from the pressure sender), run water hoses if the turbo is watercooled, put an oil return in the sump, setup a cable for the throttle, install a boost guage, but thats all minor stuff that you should have no trouble with if you got time and tools.

the cost to convert to efi is quite high thats why i went with the carby, looking at around $1000au for a cheap programable computer(why use factory if you want power?), around $50each for 2nd hand injectors, then theres about $500 to rig up a decent efi fuel system(efi hoses, return line, low pressure pump, anti surge tank, high pressure pump, regulator etc.), and then theres all the sensors and tuning which all adds upto a lot.
for less than the cost of setting the car up for efi you can have a turbo up and running with a carby, plus if you ever want to go to efi later the amount you spent on the carby setup isnt going to be a big loss, its just a few bits of pipe really hey.
A single 2" SU would probably be good enough for about 160-180hp at the wheels, a 600holley should be good for around 250+hp if you built the motor up to handle/make that much.

you can make some good power with this type of setup still, i know a guy over here thats running a similar setup to mine but he use`s 2 cd175 stromberg carbs and hes making 230hp at the wheels from a L20b(2L 4cyl), he runs about 15-20psi with water injection and his setup was pretty cheap too. he`s planning on going efi later on and hopefully getting around 300hp, not bad for a 25yr old sohc 4banger eh.
im actually quite surprised that theres noone else on here running a carby turbo setup.
later
Paddy

70 510
77 260z2+2
Sth Aus