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Ok guy's, I am throwing around the idea of building a cheap single turbo 318 to run on 5-10psi.. any 1 got any tips, pics or info?? I would like it to be non intercooled. An remember cheaper the better.
 

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I have rebuilt many 318 and several turbocharged engines but I have never built a turbo 318. I have often thought about twin turboing a 318. I think two small turbos would be sweet. Fuel injection would be best by far. Keep the compression down. Cam selection would be important but I don't know what to look for. Thx-Ace
 

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just bolting a set of 360 heads on is usually a fail on a carb motor without any other mods because it lowers the compression but lookin for a pair of em might be a good start

the right ones would breath better and take compression away without going into the bottom end
 

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Discussion Starter · #7 ·
just bolting a set of 360 heads on is usually a fail on a carb motor without any other mods because it lowers the compression but lookin for a pair of em might be a good start

the right ones would breath better and take compression away without going into the bottom end
I have done what I'm doin to the motor. The compression on my 318 probably ain't no more than stock. I'm just lookin for a cheap junk yard turbo build. I found a 20g turbo an a t3t4 off a wrx but bolth those to small?? I am not buildinga 1000hp monster just somthin fun an non n/a lol
 

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also, people use cheap Ebay turbos when doing a V8. On a 4 banger your doing 30-40 PSI of boost in a race car, not smart with a cheap turbo. If your running low boost with a v8, which low boost really means something lol. Then the cheap turbo is fine. just don't get huge with a single turbo. A 60 trim T04E or B with a turbine near 1.0 AR is fine. The hybrid uses a T3 turbine, too small for a V8. Most Holsets are also smaller T3 housings, for a Diesel that also works on a little 4 banger. A HX40 with a T4 housing, not the T3 is easier to get as the people hunting for them want the T3 version. That is also a good turbo, but it will need the external wastegate. Myself I go 60mm and run a 2.5" exhaust for the WG, then it allows a smaller turbo. Same type of thinking with the SRT 4 lol, little turbo with a big WG.

Like my PM though, you still don't want to run a carb. By the time you buy everything you need to run a carb you went past what it cost to run a used FI system. I am testing the larger "blue" TBI injectors right now to see what they'll hold and run. If they work well at 75 PSI it may be possible to run the factory system still. Give shelby Dakota owners something to do lol. Hacking the Shelby 318 computer and adding the 2 bar map and spark retard and such from the turbo computers shouldn't be that tough. Still a low boost plan as the injectors only go to about 135 lbs of fuel, but better than nothing lol. The turbo I'm doing is with the Holley pro jection 4 barrel, 4 injectors, but Holley claims they don't work above 25 PSI. Hopefuly Mr Injector tells me something different. Otherwise I am going to use a rise rate gain regulator with it.

To use a carb today you need a custom boost built carb, that means the power valve is drilled for an external vac / boost source. So you run the power valve to the intake and it only opens for boost. The valve is then a possitive pressure valve, much much larger than vac types for the fuel for boost. This also mean that you get it going and set you boost level at your fueling, you can't have different boost levels like with FI. You get a set amount of fuel and that is where your at. Go bigger or smaller in power valve for different boost levels, sucks. This is also about a $700 carb from a supercharger store.

Then comes the MSD boost retard controller.
this allows for adjustible boost retard, which means you need a $200 EGT gauge too to adjust this. That brings your spark retard to $470 roughly.

So for anyone to be stubborn and decide FI is too much work and trouble you end up barely streetable with on off switch power that costs more money and harder to live with. Megasquirt is also a great idea, but starting from scratch costs more. If you get MS and a cheap TBI your looking at 2 injectors. If it was a poly 318 then running 2 Dodge TBIs and a dual 4 intake would work, I don't know if Offy still sells the dual 4 intake for the SBD still or not. Otherwise the only 4 barrel TBI system is Holley. Then comes MPI, tough with an older Dodge unless you buy the Edelbrock intake. But then up goes cost again. Making the 4 barrel Projection the most affordable.

My Challenger is different, 2 360 TBIs. I have to get the injector flow dealt with first then I can decide. I believe the stock injectors will work at high pressure, the "performance" Holley injectors are designed a lot different and I am doubtful. I believe I will be using MS2 with the Challenger all on the computer and the turbo car will be pinch valved with the Holley system. Keep in mind though the Pro Jection system is using all the old Dodge sensors. It has 4 injectors that goe up a lot under pressure. The system also has electric fan and electronic boost control. It also uses the stock TBI / Magnum Dis hall effect sensor. Here is the system I just bought off Ebay.
Holley Commander 950 TBI Kits 950 22S | eBay

Yes the 950 system is a lot harder, starting from scratch like megasquirt. BUT it is also cheap like Megasquirt in cost. Tom, the owner of the turbo car I'm doing wants to tune it under boost with a screw driver on the wideband. Little leaner with race gas and that would make boost fueling that easy. So it may be pinch valved anyway. If I get done in time he wants to run drag week in Hot Rod mag in the street class. My retired muscle car customers don't under stand why I can't up and leave for 2 weeks.... That's 2600 miles to get there one way, then 1000 roughly in the race car and then the trip back... Us younger people in our 40s have to work!
 
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