Need help on Turbocharging a 318

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7duce swinger

7duce swinger

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So ive recently bought a turbo setup, and had some questions for all you turbo people.. Its a garret t3 turbo, it came with a bunch of tubing, an intercooler, a blow off valve and clamps lines n such.. So i wanted to know is this turbo set up okay for a 318? Or is it on the small side, would i benefit from a twin turbo setup, using the same turbos like say two t3 garrets? Or would i be okay using one turbo?.. As for what im looking to get out of it, i would like maybe 400 hp or so. somewhere in that neighborhood. Its for a 72 dart swinger if that matters,... Besides for 100 bucks i just couldnt pass it up lol, i had to and ive always wanted a turbo set up haha.. Also when people say shaft play, is that the compressor that has play or not? Sorry for the long post, any helps is greatly appreciated. Thanks!
 
You are going to need to supply a LOT more info than what you have....
 
Like what?Thats why i said i need help lol.. What do you all need to know? 318, with 360 heads 9:1 cr 3.23 rear. I dont know weight of the car, i dont expect to race it to much at all. Just some more power. Auto trans for now.. What else as i need help??????
 
How big is the T3, 50mm in size? Once you figure out what size Turbo you have then someone will reply to say if you need 2 of them. I would guess right off the bat that you will need 2. You should post up some pictures of what you got. 9:1 Compression will work. What cam is in it? I am guessing you have a 245/60/14or15 in the Rear so a 323 gear is fine if so. Auto or stick? What do you have for a Fuel System? Your going to need quite a few more $100's to get this complete and running, I do know that.
 
Ah ok thanks... A/r .48, so im guessing i need to go twins since it is small right? Auto trans at the moment, right now stock tank, to an elec. Fuel pump, not sure of hose size. Is there a specific fuel supply needed for a turbo set up. 245/60/14's right now .. Will it be a problem, if i go to 295's Later on?? As for cam i was planning on getting one for the turbo, right now i have a thumper hyd flat tappet, can i get away with using this cam or will i have to go with a cam for turbo specific applications? Yes i know its not the end of the road, i know im going to need more stuff to comlete it. Thanks for the replies
 
7duce swinger said:
Ah ok thanks... A/r .48, so im guessing i need to go twins since it is small right? Auto trans at the moment, right now stock tank, to an elec. Fuel pump, not sure of hose size. Is there a specific fuel supply needed for a turbo set up. 245/60/14's right now .. Will it be a problem, if i go to 295's Later on?? As for cam i was planning on getting one for the turbo, right now i have a thumper hyd flat tappet, can i get away with using this cam or will i have to go with a cam for turbo specific applications? Yes i know its not the end of the road, i know im going to need more stuff to comlete it. Thanks for the replies
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Yes you are going to need twins no doubt. Those are pretty small. 295 Tires will be fine, the Taller the gear just about the better with a Turbo. I would use everything you have right now. You will most likely need a new fuel pump. I like the GSL-392 from Walbro. They are about $100.00 and it will flow enough to support 600HP Easily. You will also need a regulator and a by pass ran back to the tank. Don't forget you will need a Boost Ready Carb or you will need to build one on your own. Your converter for the 318 will probably be good enough for now. Are you going to use stock manifolds and flip the sides or Headers??
 
Sorry but how can i find out if its an 50 mm or what size it is, is that the .48 or is that somethin else. The only thing i can read is that, and some other numbers, no way to post pics, sorry. Can anyone let me know where to look?
 
Sorry about that, Well i was thinking of flipping some shorties, and welding the flange back on that way. That or making my own again. Yeah i got the blow through carb figured out, is there any particular carb people like to use for forced ind. ? How would i go about making my own blow through carb, is there a kit or something someone sells? I would like to know, Thanks mad dart
 
Another thing you might do is buy a set of (cough, gag) Chivvy headers FOR a turbo, and weld the tubes to a set of Mopar flanges.
 
I'd try and off the turbo you have and upgrade to a better fit turbo also try and keep it as simple as you can twins for a newbie may be a harder to tune and will require more hardware witch equals more money more headache
Listen to maddart the walbro 392 is a good pump im running one on mine, also do some research you will find some good info on this site but there's not mine of us forced induction guys on this site you I'd recommend the turboforums for a place to start alot of us are on there as well. Response time over there isn't always great but that's where all the knowledge is at.
Any mech secondary carb can be modified for blow through I think there is a sticky at the top of this section hanger18 mods its not hard to do the basic mods but the tuning process is where the difficulty is
One more thing I'd recommend is don't buy anything else till you figure out what your power goals and the correct turbo size for your application it will save you some time and alot of money I changed my setup multiple times until I was happy
Just one man's opinion
 
Thanks 67 dart, theyd be a helluva lot cheaper lol.. Thanks also srixon, so are you saying find a bigger turbo, as to only run one for less tuning? Does it have to be a mech secondaries carb or can it be a vac secondaries? Thanks for all the info guys!
 
7duce swinger said:
Sorry but how can i find out if its an 50 mm or what size it is, is that the .48 or is that somethin else. The only thing i can read is that, and some other numbers, no way to post pics, sorry. Can anyone let me know where to look?
Click to expand...

It is the Inducer/impeller sizing on the intake side. If there are any markings on the housing you may be able to research them other wise you will need to dis assemble it and measure it.
 
srixon4406 would be correct. Go over to theturboforums.com and start some research over there. Like he said the response time is sometimes very slow. You can also just do searches and find out alot of stuff pretty quick there is MEGA information over there.

I was going to say you should get new turbo's also but I figured you wanted to start with what you have. I do know that 1 of the turbo's I am running would be a good size for your 318 and the cost is not that bad at $260.00, it is a 70mm with 1.05ar. There are guys with 5.3 Chevy's making 600RWHP with one of them. I am sure your 318 could do at least the same with some good tuning.

67Dart273 has a good idea also and this may a real good alternative by getting a set of Chevy Turbo Headers and welding on new flanges. Just make sure they clear the inner fender wells before you hack on them incase you need to return them. Also if you run twins with headers like this be mindful of where your turbo exhaust out will go cause sometimes you will be limited with room and need to start cutting up your car pretty good to get them to fit. I chose the Hedman Shorty Headers for this very reason. I wanted the exhaust to exit past the K Frame and everything to fit under the hood without a Hood Scoop.

Plan,Plan and then Plan some more is the best advise. I had to change directions a few times with mine and it can get expensive real quick when that happens.
 
Yeah imma check out the turbo forums im not jumping in to this right away either.. Ive been looking on amazon/ebay and other sites to see whats cheap,im mostly looking at the turbo's around 250-350 bucks, to keep on the low side. what would be a good turbo, im thinking of a single for now, theres t3/t4 hybrids for 230 or so,what would be a good single turbo to run with my 318, as im not looking for 700 hp or so more like a quick boost in power around 450or somewhere in that neighborhood. Thanks for the help so far guys.
 
Yeah i was looking at one of those, pretty sweet lol, and a gt35 i think i was also considering at least i think it was a gt35 , so with that specific one, how do i go about the headers, would i route both headers into it or one. The part i dont get is if i route one header, the other header just sits down under the car alone? Or would it be better to route both headers into that one turbo? Can someone please clear that up for me. By the way thanks for all the help mad dart
 
So the first link u posted for the gt45 would be a good candidate right? Im thinking ill use one of those for a first time build then grow into a bigger one. So this t3 i have, what would it do exactly pretty much nothing right? Would it even do anything at all performance wise, Im not gonna use it now that i know it is too small, most likely a paper weight for my desk..... this thing is tiny lol..
 
First you need to set a horsepower target & stay with it through the design process. You first said 400 horsepower, then 450 horsepower.

Second, you need to learn to read a compressor map & begin thinking in mass air flow, generally expressed in pounds of air per minute on compressor maps.

For your initial goal of 400 horsepower from a 318, the basic calculation shows 40 lbs/min. airflow, and a little under 7 psi of boost with a discharge temp of 160f. For 450 horsepower, you need 45 pounds per minute & 9.5 psi of boost.

Next you need to calculate the pressure ratio. That is atmospheric pressure plus boot pressure, then divided by atmospheric pressure:
14.7 + 7= 21.7 then 21.7/14.7 =1.476 That leaves you with a 1.476 : 1 pressure ratio.

Garrett shows 3 compressor maps for the GT35 series. None of them will support 40 pounds per minute flow at that pressure ratio. The map shows that compressor way out in the choke area. However two of them would be just about right.

For a single turbine on a 318 a T70 would be as much as you would need at that power level. A T72 would be ok, but it would barely be spinning - look at the T72 map:

t72.gif


Now, that same unit @ 650 horsepower pushing 65 lbs / min & a 2.80 pressure ratio (23psi) puts things right in the sweet spot on the map.

Good luck with your project.

B.
 
Here is an example for you. 1 Single GT45 on a Junkyard 5.3 and a 75 shot of Dry NOS.

This is extreme but you can get a good idea of what 1 of the GT45s will do for your 318 tuned properly.

[ame="http://www.youtube.com/watch?v=wTV8QTIVYB0&feature=player_embedded"]michasmovie.wmv - YouTube[/ame]
 
I think i read that somehwere, and another one, which was just dyno pulls.. Well i said 400-450, i meant somewhere in that area, lets say 450 then.. Thanks again maddart, and thank you bohica for the info .
 
If you want 450 now, you will probably get hooked and want more later.

If you plan to run a single turbine, then a T72 would be the way to go. At 450 horsepower @ 5500rpm, with a BSFC of .5, a VE of .8 & a charge temp of 185f you need 12psi @ 45 lbs/ min flow. That is a pressure ratio of 1.8

Plot the point on that map where 1.8 & 45 cross. Keep in mind that the center island in that map is the maximum efficiency for that compressor. The curved lines that cross the islands are turbine speed.

B.
 
bohica2xo said:
If you want 450 now, you will probably get hooked and want more later.

If you plan to run a single turbine, then a T72 would be the way to go. At 450 horsepower @ 5500rpm, with a BSFC of .5, a VE of .8 & a charge temp of 185f you need 12psi @ 45 lbs/ min flow. That is a pressure ratio of 1.8

Plot the point on that map where 1.8 & 45 cross. Keep in mind that the center island in that map is the maximum efficiency for that compressor. The curved lines that cross the islands are turbine speed.

B.
Click to expand...

You are giving some great information and technical at that.:D
I plan on my charge temps being under 100*, the cooler you can keep the charge air the better. This is where an intercooler can make or break your system. Meth injection can also help keep the charge air cooler, along with the use of e85, Race fuels & Nos. Pick your poison.
 
Thanks for all the input guys. So since some turbo's are oil cooled and some water and oil, where do you get the oiling from. Can i weld a bung into the oil pan, or would i be able to take a fitting off the back of the block.?in other words where would the best oiling area for the lines be.
 
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