Spare parts single 318 turbo build

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oliver

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Building a extreme budget turbo 318, almost all of the parts will be parts on hand from other builds with the exception of gaskets and consumables. This motor will be replacing my high revving 350ci 340 that is in my 66 b-body ( I know, but small block stuff isnt too hot on the b body forums). The 340 was amazing being a solid roller high compression engine backed by a 4 speed, but it was just not enjoyable on the street since the power didnt come on until 4500 and it would pull past 7500.
First up is the heads, one is a J head and the other is a X head. Both came from different engines, the J had 2.02 valves in it and the X had 1.88. I had a set of no name 2.02/1.60 stainless valves, so I used those. Also cleaned up the ports some with some mild blending/port work. Springs are from a set of aluminum heads, they are crane springs comparable to 340 springs. That motor got set up to be a hydraulic roller so it had beehives put in.

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I haven't cc'ed the heads but i would think they are in the 70ish range after the small cut that was made. I'll update the thread as I progress. I found a forged crank in the corner of the shop that came out of an old 318 powered water pump. It looked rough but mic'ed out good, some minor rust on a few journals but will only be polishing the journals not cutting. remember.... cheap.
 
What a neat project , 10 years ago you would have never even heard of anyone doing a turbo on a mopar v8 keep us posted
 
What a neat project , 10 years ago you would have never even heard of anyone doing a turbo on a mopar v8 keep us posted
Thanks. I love turbo builds, this will be the first one I'm doing on my car. I've done plenty for customers. Usually when it's a customers car the budget is pretty unlimited.
Just before I left the shop my pops reminded me that I saved the rods and a few pistons out of the engine the crank came from. Going to see if I have a set of pistons that I can hang on it that will be close to the weight of the set that came out. I'll save 350$ on the balance job if so.
 
Since I have the crank is being polished, I went rooting around for valve train parts. Found a couple sets of roller rockers, some crane golds, old set of comp magnums, a set of 273 ductile, and the good ol' stamped sets. Dunno what I would consider using. I also found 3 used cams, i'll have to throw them in some v blocks to measure them out.

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I've got more rooting around to do to find parts. This is gonna be one hacked together motor :rofl: I hope I can make the combo work.
 
Do a big bang 318.....
Dyno test it 7, 14, 29psi.......
Inspect what breaks...repeat.
 
Do a big bang 318.....
Dyno test it 7, 14, 29psi.......
Inspect what breaks...repeat.
Dyno cost money. I'll test it in car. Im thinking max boost of around 12-15 psi. Dunno what will go first, head gasket, rods, or pistons.
 
Looks like you have a nice stash of parts to choose from.
 
Looks like you have a nice stash of parts to choose from.
That's what happens when your family business been around in the same spot for 40 years, hah.

First money spent, crank only got a $80 wash/polish because it mic'ed out good. Std/std on the journals. every main journal has rust damage, but not bad enough to be detrimental. Forged industrial 318 crank, pretty rare iirc.

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If i have the time,
 
Ooh, do the megasquirt and Ill do a parallel build on my stock 63 273/2 block. I got an MS2 and a Holset HX35W, magnum logs on backwards to dump out the front...Jeep throttle body on a MPFI intake. Im a little ahead of you as I already got the Isky "turbo grind" camshaft. Even got some ported 2.02 heads (no notch yet, shame to use them on a turbo build) I can use or just the 'ol 273's.
 
Ooh, do the megasquirt and Ill do a parallel build on my stock 63 273/2 block. I got an MS2 and a Holset HX35W, magnum logs on backwards to dump out the front...Jeep throttle body on a MPFI intake. Im a little ahead of you as I already got the Isky "turbo grind" camshaft. Even got some ported 2.02 heads (no notch yet, shame to use them on a turbo build) I can use or just the 'ol 273's.
I cant remember what megasquirt i have. Its got a little daughter board plugged into where the old processor went. I'll have to dig into it more. What intake manifold is it? That hx35 is awful small, if you've got the 12cm3 housing on it, it will be in boost by 2000 rpm's. Would be a fun charger in a stick shift car. I'll have to dig through my turbo pile to see what i want to run. I've got probably 2 dozen sitting around :lol:
 
You got the same MS2 if you got the MS1 with the upgraded daughterboard, just like mine. 4X the fuel map resolution and autotune ability over MS1 if you buy tuner-studio license. My manifold is my sheetmetal intake I made.
Pishta's sheet metal intake
Gonna have to be bank fired as MS2 only has 2 injector channels....? I got a smaller turbo but no waste gate. The HX35 has an honest 2 9/16 exducer and a 14cm3 housing on it (has 14 cast into hot side, no 12 to be seen). I had a larger one but I sold it 2 weeks ago to an LS guy for #2 on his build.
Early boost is fine by me as it has 2.92 or 3.23 gears in it, Cant remember as its been a while since I been in there. I have a welded internal brace that ties the top platet to the bottom as 10 psi boost will generate a huge amount of force on that welded top plate, at 112 square inches. May have to set the limit at 10, not sure what 1/8 welded plate can handle.
 
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I thought J heads were U heads with the edge cut off by that cast box. Who ever seen a backwards J? Yeah, I know they are real J's from the one on the underside of the head. They both look 2.02 to me as the valves are almost touching.
 
I want to see a 273 (any year, 9:1 or 10.5:1) Stock Bottom End....get a 70mm turbo installed....and turned 6500 with 7, 14, 21, 28psi.....and prove what exactly one can Take, and what breaks first.
 
It would surprise everyone......
By my math.....(and I dont claim to be any kind of mathematician)
235 x 1=
235 x 2 = 470 at 14psi
235 x 4 = 940 at 28psi

180 x 1=
180 x 2= 360 at 14psi
180 x 4= 720 at 28psi

Either 273 falls right into the range of a GT45 or s475.

And a 273 can make More NA power than 235....right?
A 273 has the smallest bore of the LA's, and the thickest factory blocks, right?.......surprised someone hasnt done this yet, just because
 
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I've never seen a 1.88 X head.

I mixed it up. 1.88 in the u/j head and 2.02 in the x head.

I thought J heads were U heads with the edge cut off by that cast box. Who ever seen a backwards J? Yeah, I know they are real J's from the one on the underside of the head. They both look 2.02 to me as the valves are almost touching.

Yes, U head. Lol. Now they are both 2.02/1.60 after i did the head work.
 
I mixed it up. 1.88 in the u/j head and 2.02 in the x head.



Yes, U head. Lol. Now they are both 2.02/1.60 after i did the head work.

Well dang. I was ready to see somethin new. lol
 
I dug the block I'm going to use out of the store room. It was a 318 out of a 70 challenger. Customer wasn't happy with 350ish hp so I built him a 650hp 512 stroker. It's .030 over, had one bad bore that had a sleeve installed. Beyond that, pretty standard. If I recall, I gave him a $150 credit for keeping the block.
I stuck the crank in it and hung a set of plane jane 318 pistons that I had on the shelf. The rods bushed narrow 318 units. Looks like the piston is .084 down in the bore! Lol. I'll probably use a .039 compressed head gasket and I'm guessing 70ccs on the chamber volume. That equals roughly 7.8:1 static compression.... Little low but will be easy to toss 10-15 psi at it without worrying too much about detonation I suppose.
I saw several old boxes of piston rings with no part numbers. Hoping one of them will work. I also need to see if I can avoid doing a balance job. I'll do some weight comparisons and continue the rest on Monday.

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well, if you find a set of 273 STD rings in 3.625" ...toss them my way!
Holset HX35W
56.60 mm; Exducer:74.71 mm; Trim 54.8 and I got the 14cm3 so whatever that changes. Supposedly a 450HP potential on a 5.0. The other turbo I have is even smaller with no wastegate so that gonna get saved for the slants Supra CT26 upgrade if needed.
 
Dyno cost money. I'll test it in car. Im thinking max boost of around 12-15 psi. Dunno what will go first, head gasket, rods, or pistons.
My vote is head gasket between 12-14 psi. Several of us have tested this theory.
 
well, if you find a set of 273 STD rings in 3.625" ...toss them my way!
Holset HX35W
56.60 mm; Exducer:74.71 mm; Trim 54.8 and I got the 14cm3 so whatever that changes. Supposedly a 450HP potential on a 5.0. The other turbo I have is even smaller with no wastegate so that gonna get saved for the slants Supra CT26 upgrade if needed.

Never thought a hx35 would make that kind of power on a gasser. I have a small collection of them from 5.9 Cummins and they are the first to go as they are already undersized on a diesel engine that only spins up to 3200 rpms. I bet we don't have rings for a 273 bore. I don't ever remember building one.

My vote is head gasket between 12-14 psi. Several of us have tested this theory.

Block deck and head surface were finished for mls gaskets. Thinking of doing the .027 cometic gaskets. Not too excited about the $80 price for one gasket tho.
 
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