Possible turbo 318 build

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Rockerdude

Rockerdude

Rock n' Roll and A-bodies
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In the near future, I may be building a turbocharged 318 for my 65 dart. I was wondering what it would take to get over 500 horse with about 10-12lbs of boost with a stock headed, hopefully a mild hyd roller cammed motor.

I will definatly go to forged pistons and rods, but what about the crank? I heard that all 273 cranks are steel, but are they a direct bolt in to a 88 roller 318 block?

Thanks, RD
 
Hmmmm.

So your question is:

What will it take to get 500hp?

The general rule of thumb is 1.0 Bar will yield 100% the NA horsepower roughly.

So, 1.0 Bar = 14.7 psi

Naturally Aspirated 318 with 9:1 CR or less...would be required to make 250 hp before forced induction to attain the hypothetical 500hp on 14.7 psi.

If you want to run a lower boost level (say 8-10psi) and make the same power your 318 would have to make more power before boost to be able to reduce the boost level and make the same amount....understand?

Also, the ignition timing and fuel system would have to be upgraded to maintain the correct timing and volume for the newly added Air Pump.

The best place for you to start with your quest is:

http://www.theturboforums.com/smf/index.php

Then, get the Book : Maximum Boost by Corky Bell

Then bust out the check book, and your dream is as doable as the $$$$ you throw at it.
 
Prine said:
Hmmmm.

So your question is:

What will it take to get 500hp?

The general rule of thumb is 1.0 Bar will yield 100% the NA horsepower roughly.

So, 1.0 Bar = 14.7 psi

Naturally Aspirated 318 with 9:1 CR or less...would be required to make 250 hp before forced induction to attain the hypothetical 500hp on 14.7 psi.

If you want to run a lower boost level (say 8-10psi) and make the same power your 318 would have to make more power before boost to be able to reduce the boost level and make the same amount....understand?

Also, the ignition timing and fuel system would have to be upgraded to maintain the correct timing and volume for the newly added Air Pump.

The best place for you to start with your quest is:

http://www.theturboforums.com/smf/index.php

Then, get the Book : Maximum Boost by Corky Bell

Then bust out the check book, and your dream is as doable as the $$$$ you throw at it.
Click to expand...

All good advise. If you are into rebuilding your turbo,get a used unit out of the wreckers.Intercoolers can be had there too.Might save you some coin.
 
Rockerdude said:
Thanks a ton guys, all the advice and help is very much appriciated 8)

As for the turbo, I was looking in to a sts universal single turbo kit listed here..

http://www.ststurbo.com/universal_turbo_systems

What do you think?

Thanks again. RD
Click to expand...

you need more engine to get your power goal from that. that kit really is only capable of 5 to 7 psi. If your going for a turbo engine make sure you get a forged crank and rods as well as the forged pistons. Stock iron heads won't cut it. Boost is one thing but boost won't make up for horrible flow. So at minimum you should smooth the flow by porting the heads. But at that point with factory 318 heads I'd find something better.

Grab yourself some headers flip them side for side so they point forwards and mount ether a y pipe to one turbo or a turbo on each header, Increase oiling with an external system running to the turbo's and feeding the engine, increase oil flow through the block by increasing oil port sizes.
 
CanadianGT said:
Stock iron heads won't cut it. Boost is one thing but boost won't make up for horrible flow. So at minimum you should smooth the flow by porting the heads. But at that point with factory 318 heads I'd find something better.
Click to expand...


I would have to disagree somewhat. Forced induction will improve the amount of charge a cylinder head can flow. BUT, the thing to remember is that Boost is only a measure of the resistance to flow between the pump (Be it super or turbo) and the head of the valve. So say you bolt a hairdryer to a bog stock 318, and it makes 10psi of boost. And then you swap the heads for some real sh1thot heads like say some W2's, the boost level would fall to a reduced number due to reduced resistance in the intake tract. This analogy is kinda flawed, due to the fact that the boost figure with a turbo is usually controlled by a wastegate. So although the boost figure might be the same, the volume of charge which enters the chamber will be greater. More charge, means more chemical potential energy and greater thermal expansion and more go!

But I digress. The other side effect of a less restrictive intake tract is due to the charge being compressed by the narrow tract, less heat is generated. Less heat=more density, and more power.
What I'm saying perhaps pertains more to superchargers, but turbo's are still quite similar. I know a bloke who was able to max out his standard injectors, just because to heavy porting. Although the boost level was still at the standard figure.
 
Hmm, this is very interesting...:read2:

Ive heard that all LA 273 cranks are forged, if true would a 273 crank fit in a late model LA 318 block?

Thanks again for all of the input,
RD
 
I do not remember correctly, but I think you will get som issues with the converter? the 273 have too small center-hole in the back of the crank? or is this only if the crank has come from a stick trans?

500turbo-hp is doable on a stock 318 shortblock i believe! remember a turbo make the cylinder pressure furter down on the stroke, this is not stressing the piston and rod as much as a high output n\a engine who has the pressurepeak near tdc. you could also back of timing at the lower rpms (<4000rpm)to avoid the tq-peak early in the register that usually blow the shortblock in a turboengine....

the main rule is that a strong n\a engine needs less pressure to make great turbo-power compared to a low hp n\a engine with boost. this low-output engine have to work hard to get 500hp,while the high-output does not struggle to get a little more:)

I'm sorry for my bad english ! hope you understand someting at least!
Turbo is underestimated!8) its CHEAP and easy power! at least if you can do something in the garage yourself!!
 
Thanks again to all. I have a bit of saving up, and research to do before I start on this journy for power. Ill keep updated
 
318's had steel cranks if they were a truck engine in the 70's with a 4-speed or if they came drilled for a 4-speeed. At one point they startee shot-peening the cast cranks for the trucks, but not sure what year.

I have one an engine my garage, and another in the engine in my Ramcharger. And Dad's got one in an engine in his Barn.

I know the one in my garage came out of a 77 3/4 ton P/U.

At any rate. They are out there for more than just the 273.

Now for Turbo, You'll probably want the dish pistons and lower C/R. Why not build one non-turbo. The turbo's wont fit under the hood of your 65 very well. Supercharger might fit better. Put a stroker kit in it, and engineer it to push the 400-500 hp you are looking for. My .02



I've never compared the steel crank in my 273 to a 318 steel crank OR cast crank.
 
I didnt really think about truck motors.. That opens up some more options...

And Ive been adding it up and it might actually be cheaper to build a boosted 500hp motor insted of a N/A stroker pushing 500hp. I also like the idea of being the only guy with a turbocharged 65 dart gt around.. Well in Arizona at least. :toothy8:
 
Hi Rockerdude,
As has been said use the best flowing heads you can afford or get hold of.
Keep comp ratio to 8.0:1.
For reliability definitely use forged pistons and try to install oil sprayers to spray the bottom of the pistons to help keep them cool.
Use only fully synthetic oil. And install water injection along with an intercooler.
Turbo's do generate a lot of heat so use the biggest radiator you can get hold of.
Don't over cam it. And even though you want to achieve 500hp, peak hp isn't that important with a turbo as the torque band has been more than doubled by using the turbo. Keeping the revs down will help with reliability.
When others are revving the hell out their n/a motors to get into the torque band you'll just blow right past them.
You can get 16G turbo's from the eclipse, Galant VR4, cheap from ebay, a pair of them should work fine on a 318 and will be capable of flowing more than 500hp.http://cgi.ebay.com/ebaymotors/TD05-BIG-16G-Turbo-Turbocharger-EVO-3-4G63-4G63T_W0QQcmdZViewItemQQhashZitem25580d8166QQitemZ160391070054QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
Make up your own headers out of steam pipe, you can buy mandrels at different angles and weld them together.
Hope this helps.
 
I will probably go with the iorn RHS LA-X heads, they seem to flow very well and cost alot less than Eddys and Indys. I also like the closed chamber design, but how am I going to get such a low comp ratio with forged pistons?

Thanks to all for the input. RD
 
chewy said:
The turbo's wont fit under the hood of your 65 very well.
Click to expand...

This is why I wanted to fab up a rear-mounted turbo system, no custom headders, way less heat to the turbos, and way less under hood temps than under-the-hood turbo systems..
 
it would take 2 of those to make 500.

When it comes down to it.....you need a minimum of a 60mm Compressor inducer and a .85 A/R 58mm exhaust housing and when I say Minimum.....I mean minimum for a single turbo.

The turbo you linked to is 10mm smaller and would suit upto a 2.5L 4 cyl perfectly.

The 60mm Compressor turbo I recommended as a Minimum will flowout around 500whp....and by that I mean it will make 625-650 at the crank, on 1.4 Bar/20 psi and race gas.

Here is where you need to shop for a turbo:
http://www.precisionturbo.net/small-frame-turbochargers.php


Good Luck.8)
 
Thanks for all of the great advice and information Prine, you really know your turbo stuff.
:read2:
 
for a bare minimum Single Turbo for your 318....ok...on a Penny Pinching Budget...maybe....and I'll tell you WHY.

IF you have 8:1 Compression....you might be able to squeeze 20 psi with that turbo and make 480-500 at the wheels....but if you will open that ebay link/window and look that those specifications.....that turbo is a T3 twin scroll exhaust housing (another words-divided exhaust inlet) with a 2.5"discharge....but the Kicker for the Flow Limit is the Compressor INDUCER...57mm is 3mm LESS than I recommended for a minimum.

You can only stuff so much air through a certain sized hole.....and as you begin to play with exhaust driven compressors...you will very quickly discover the limits of small diameter piping....because it all boils down to VOLUME...not PRESSURE.

60mm is 2.36 inches and 2.5" is 63.5mm

This is semi important.

A 2.5" 18ga exhaust tube will flow enough air for roughly 330 hp, (and I am NOT going to go into the math of interior pipe volume or fluid and thermal dynamics) so suffice to say a turbo WHILE not compressing air needs to be able to flow the amount of air the Driver Engine makes at peak hp Naturally Aspirated.....in your case lets call it a Mild 318...and peg the NA peak hp around 350 crank hp.....the Base size for your Turbo - Compressor Inducer should be around 2.5" and the exhaust should be sized just a tad BIGGER for thermal expansion flow capability....so around 65mm Turbine Exducer.....because at 1x atmospheric pressure, the exhaust pressure also increases roughly 14.7 psi, then flow is doubled, so there it is, a properly designed/setup turbocharger system will yield 100% more power than the driver engine made NA.

The A/R number most turbos list is the Ratio of the size of the Exhaust Inlet to the turbine exducer size, and is generally given to help determine spool-up characteristics....the smaller the A/R the lower in the RPM band full boost can be achieved, the larger the A/R the higher in the RPM band full boost will be available. You can run a T3 exhaust housing...but I highly recommend a T4 housing if you stick with a Single Turbo App.

For a 5.2L engine with a RPM Ceiling of 6500-7000 rpm, I would suggest a .96, or even a 1.06, and would expect full boost around 3500-3700 rpm.

I would suggest a SINGLE Tial 44mm wastegate.

The price/quality of the turbo you settle with will and can only be decided by and funded by you....but I personally would start with a quality piece and not a Ebay Special.


Ohh and NOT ALL THOSE Turbos' cost $1200.00 When you say GT or Dual Ball Bearing you can expect the price to double over the cost of a regular thrust bearing type turbocharger.

I have called them up personally, NUMEROUS times and ordered a custom spec'd turbo and had it to my door for less than $800...Quality is not Cheap my friend.

Forced Induction is one of those things that will hammer home that message.
 
Yea I hear you, you definatly pay for quallity. Same goes with alot of things, Im going to have to really know where to spend my $$$. Im going to need to learn alot more about forced induction before I start spending left and right.. Any idiot books available on the subject of turbos would probobly be a good start I think...

Thanks again Prine for all of the helpfull information. RD
 
A wery simple rule to size the compressor side on a turbo is:

inducer(mm) * inducer(mm) / 6.

57mm * 57mm / 6 = 540hp


and a wery easy way to get a cheap turbo, is to look at trucks! if you have a 5L petrol engine, you roughly need the turbo from a 10L diesel engine.

so by looking at a Scania 11L or 14L v8, you will find what you look for!
I'm sure you have alot of trucks over there that are out of business(?)!
 
Don't trucks run much higher boost figures which will make them less efficent at the lower boost number that a car will run?

I got offered a brand new garett T04E last night for about 1/3 what it's actually worth. Would that be any good on a 318?
 
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