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I'm looking for all the help I can get, I've raced on the dirt for about 9 years. Due to going to college we sold the race car, however I ended up staying local and going to my community college. This will be my second year out the car and being away from my passion is painful. I'm attempting to start piecing together a 318 based sprint car enginewhich will eventually power a USAC West Coast 360/VRA 360 sprint car. You may be familiar, but these small block V8s are very expensive to build due to the high number of extremely specialized parts required. For now I'm just going to try to get the ball rolling on an engine, while the cost may be too high to jump right into sprint cars; at earlier stages in the process I may be able to get it into a VRA Hobby Stock then maybe an IMCA modified. I need all the help I can get; I'm looking for mentors, supporters, sponsors, fans, and anyone else who is willing to help. I need all hands on deck. Here in minor league racing in local So-Cal, Mopars on the dirt tracks are almost non-existent. I'd like to change that. It might be easier and cheaper to build a small block chevy, but unless someone gives it to me I'm not gonna spend any money on something that isn't a Mopar. It's been my dream to have a Moparsprint car for about 7 years now, and I'm on the search to make it happen. I have a 74 Duster, everything that has been done to it I have done myself and I strive to be as self sufficient as possible, daring to do things that are tedious and difficult; but I'd rather spend the money I have on the tools to do something than to spend the money on labor. As a result of this mentality I continue to learn more and more about cars, I love it. I'm willing to do all the work myself I just need someone to help me by either teaching me, or supplying me with the resources to do it myself (for example, the machining to the crank and rods).

Here's what I have:

-I've got a forged 273 crank that needs to be turned, I'd like to have all the old school hands on work done to it; radiused journals, nitrided, lightened, etc. It needs to be inspected and worked someone who knows what they're doing.

-I've got a set of bushed 318 rods that need to be worked over; I'd like to get them shot peened, inspected, lightened, machined also by someone who knows what they're doing.

The Goal:

Okay, so this thing is going to be a beast. Unlike almost any high rpm race engine built today, I'm going to be using almost an entire OEM short blockthat's been reinforced and done up old school to maximize strength. I wanna pull out all those old tricks for when there were no specialty parts available. I have the rods, and the crank. I'm gonna use an 318 block. I'm not sure what heads would be best, but they will need to flow 300+ cfm. This engine is going to make max power between 7000-9000 rpm in sprint car trim. Maybe less if it's to go in a hobby stock or a modified first. It will need to be built for maximum longevity due to the very tight budget I have. Roller lifters, rockers, and maybe even a roller bearings for the cam. We're talking 13:1 compression at the least, so it's gonna need to be o-ringed. All the hardware will be ARP. I'd like to maintain shaft mount rockers of the LA variant because I strongly believe that they're just better than the oil through the pushrod stud mount type. It will be a dry sump also. The class limit for displacement is 360 cubic inches, which will be hard to get out of a standard 318possibly, at a later time a stroker crank could be installed possibly but for the time being about 326-332 c.i. should suffice.

Idea for what's going to go into it:

-Early 70s 318 block (maybe a truck block for the thicker casting) or a late 80s block for roller lifters
-Bore Sleeves
-ARP Rod bolts
-ARP Main studs w/windage tray
-King Bearings
-Main Stud Girdle
-Forged Pistons
-Bushed Piston Pins
-O-rings for heads/block
-Double Roller timing chain or gear drive preferably
-SFI Harmonic Balancer?
-ARP Misc. Hardware
-3 or 4 Stage Dry Sump oil pump
-Cam mount or belt drive for Oil Pump
-Kevko Oil Pan
-Oil Tank
-Magneto or electronic ignition with a small alternator(No battery)
-Roller lifters
-Roller Rockers
-Titanium/Chromoly Retainers
-Hardened locks
-Dual Valve Springs
-Oval Track Cam
-Heavy duty rocker shafts
-Heavy duty rocker hold downs
-High pressure Fuel pump
-Carburetor for now (hilborn injection eventually)
-Brodix/Edelbrock/Procomp Aluminum CNC-Ported heads (eventually)

and probably more that I can't think of off the top of my head. Thanks for reading
 

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A don't think a word "budget" can be really used when you talk about building a sprint car :)
Are you going to build it on the base of your 74 Duster?
 

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I also live in SoCal but gave up on attending sprint car (and other short track series), because, as you said, Mopars on short tracks are almost non-existent and I don't waste my money to spectate at races full of "Brand C" powered stuff. I admire you for attempting to build one but you'll have a long road to make it really competitive. On this board, "Fast Eddie" would be the one to converse with as he worked on performance small blocks for years at Chrysler.

Why would you try so hard to build a 318 when there were some very competitive 360 Mopar engines in Sprint Cars and Outlaws as recently as 6 or 7 years ago? I posted a lot about them on the "IRL/Sprint Car/WOO" thread in the historical motorsports section. I think that I posted that there was one year with 4 major engine builders building competitive Mopar Sprint car motors, including for Tony Stewart's Mopar teams. With that many teams having run Mopar motors, there may be some engine blocks and other good stuff still floating around for sale. The companies that built the motors (Kistler, Stanton, Guerte etc) might be able to offer you some tips if you contact them.
 

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I don't understand why you are starting with a 318 when 360s are plentiful.

Mike
 
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. You may be familiar, but these small block V8s are very expensive to build due to the high number of extremely specialized parts required. For now I'm just going to try to get the ball rolling on an engine, while the cost may be too high to jump right into sprint cars; at earlier stages in the process I may be able to get it into a VRA Hobby Stock then maybe an IMCA modified.
 

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I think the issue is that most tracks for hobby class limit to a 358cid engine, thus , which has always eliminated the 360cid engines and blocks, however, the heads will fit just fine on the 318cid, but you have to have a much earlier version with thicker castings to be able to bore it out. Has been a while since I have looked into these parameters though, there could be a mistake about the 318Cid blocks. As I remember, best way is to start with the 340cid block, more meat in the castings to overbore with. Buy 360cid blocks are rare these days
 

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For what it is worth, our local class allows up to 370 c.i. for Mopars in the hobby division. The top Chevy guys (360 c.i. limit) are easily spending 7 K. to 10 K. on their motors and producing over 400 horsepower on a two barrel carburetor.
 

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Wow. Itll take me a week to respond to this, but I will say this.

Ive been involved in the West Coast 360 Sprinters, was engine chief on a couple of the winners of the West Coast Nationals. I KNOW what it takes to make an engine live under the rigors of sprint car racing.

Stock 318 parts aint gonna cut it. ONLY thing that MAY be usable would be the 273 crank, but in comparison to what you would be running against, its so heavy that you would literally be being accelerated away from coming out of the corners. 318 rods are a disaster waiting to happen at those RPM's, 340 rods, or 360's that have been bushed would be better. But for the money spent you can buy Scat I beams for $350 from Summit and be money, and parts quality, ahead of the game.
360 rotating assembly would be a much better place to start, but there are issues there as well. Later model 360 Magnums are pretty easy to come up with, and MRL Sells a drop in solid roller lifter that requires no block mods to make work. However, both LA and Magnum need oiling system mods to live above 8000 RPM reliably..... and that's another chunk of coin. Stock main webbing is also suspect, and a splayed 4 billet 4 bolt main/half fill is most likely your best bet to make a stock block work ( LA 318/340/360 OR magnum, doesn't matter ).
Heads are going to be your big holdup. Most of the Chev guys are using Brodix 11X heads, and those are good for an easy 340 CFM on the intake. To get those kind of flow numbers out of any SB head, you have to step up into Indy or W5's at a MINIMUM.... PLUS you have to be able to find injection setups for them, and AFAIK Kinsler and Hilborn only make them for W8's and W9's. So plan on budgeting W9's for your build. And 59* W9 builds have their own set of issues that limit engine RPM for longevity. The pushrod angles are so severe, that they cant reliably be run up in those RPM's for long periods of time. We wont even talk about the price of quality ( T&D/Jesel ) rockers for that build.

So, unless you want to be one of the perpetual squirrels at the back of the pack, best bet is to look on racing junk.com for a used USAC or WoO 410, and redo the rotating assembly to destroke it for your needs.

Oh, another issue is going to be building compression for your build. Unless you have some SUPER small CC heads, getting the 14.5:1+ compression required to be competitive ( one of ours was 15.2:1 compression ) is either going to require a lot of stroke, or some custom heads with 50 CC chambers.

IE, you have a lot of roadblocks, and some of the limitations you are putting on yourself are just that, limitations that will keep you from having fun doing what you want to do. Because running middle-back of the pack, and blowing up poopies, and wrecking poopies, aint no fun. And it sure as hell aint cheap.

What I detailed above is just the tip of the iceberg, there are more limitations and reasons to do it different/correct than I have time to type out. Take it for what its worth.
 

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Ive been involved in the West Coast 360 Sprinters, was engine chief on a couple of the winners of the West Coast Nationals. I KNOW what it takes to make an engine live under the rigors of sprint car racing.
Were you racing Mopar stuff?.................................or "Brand C"?
 

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Were you racing Mopar stuff?.................................or "Brand C"?
Brand C, but the whole time I was plotting and planning on what it would take to put a real motor in the car. Even approached the car owner about it at one point, and took him for a quick jaunt in my 68 340 Cuda to show him that Mopars could make power. I had him set his wallet on the dash, told him to hang on, and launched the car and his wallet smacked him in the face :p Anyway, this was about 5 years before Mopar got involved in sprinters heavily with Stanton and crew. Funny enough, one of our drivers was Jason Sowold, who is now running with the WoO tour, and we used to race against Kasey Kahne regularly as well.

Guess I was just a bit ahead of my time eh? lol.
 

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A route you can go with the heads is the W2 or Commando heads, which will port out to above 300cfm. They require a matching intake, but with the route you are going, not that expensive but worth the money with the setup, including the 2.02 intakes, which fit inside the 318 bore, so that would take care of breathing. Scat rods would be best, also. Given the external dry oiling system and all, just make sure all your oil holes are champhored well and galling bearings shouldn't be an issue. Sounds like you are going to have some fun. Additionally, if sleeving the block is something you were going to do, you could step up to a 4.04 bore and have a 340 out of a 318 along with the steel crank, you should be pretty sturdy with a main saddle girdle.
 

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Discussion Starter #13
Why I'm not building a 360 - 360s have different size main journals than 273/318/340 and no 360 has ever come with a forged crank. Yes, you can buy an aftermarket forged crank with 360 journal sizes but it's gonna cost upwards of $700. Almost all of the extra displacement in a 360 comes from the longer stroke, they make 3.58 stroke forged cranks for 273/318/340 sized journals. So if I get extra money, I can always rebuild the bottom end and keep using the 318 block. A 318 block/bore that is .030 over with 360 stroke of 3.58 will result in 354.3 cubic inches of displacement. Also, I already have a 273 forged crank and a 318 block. Also, the stroke of the 273/318/340 crank has a more optimum stroke to rod ratio of 1.84 approximately with 6.123" (factory length rods) and the most optimum of almost exactly 1.8 with 6.000" rods. Also, the smaller main journal of the 273/318/340 cranks means less friction in the main bearings, and a 273/318/340 crank weighs less than a 360 crank. I don't know how many of you guys have the Mopar Performance books, but I've been reading them quite a lot. I'm fairly sure the 273 forged crank is also the same 1053 alloy as the Mopar Performance racing cranks. Not to mention, almost all high revving Mopar small blocks use 318/340 main sizes, not those of the 360. I'm sure they probably do that for a reason. And, almost all 360's have lower compression ratios than 318s. 360s never came with bushed piston pins, 273s, early 318s, and 340s all did.

As far as the stock forged 273 crank goes - I'm going to see about getting it full radiused, nitrided, stress relieved, and lightened.

As far as using stock rods goes, small block Mopar rods break down like this. All SBM after 73/74 I believe had pressed pins (with exception of 340 in the year of 73). The 360 never had bushed pins. The 273/318 used the same rods in the earlier years (late 60s). The 340 had heavier rods than its smaller counterparts. Once the 318 switched to pressed pins, it used a forging that was very similar if not identical to those of the 360 (same forging number). All SBM rod lengths are the same, as are the small end and big end sizes up until the Magnum. So it would make no difference if I used late 360 rods instead of 318 rods. I believe the later pressed pin casting is slightly heavier than the earlier bushed pin one. Either way, I have a set of late pressed pin rods from a 318/360 that have been bushed as well as a set of earlier 273/318 rods that are bushed from the factory. If I end up using OEM rods, I'm going to shot peen them, maybe lighten them, and equip them with ARPs 2000 rod bolts (which I'd like to use with whichever rods I end up using). However, I'm now considering using either the Scat or Eagle Rods depending on what my engine builder says in either the 6.000" or stock 6.123" length.

Block - As far as using the stock 318 block, the earlier block which I have is a heavier casting (68) than the later ones with pressed pins. I'm planning on removing all the casting flash, sharp edges, and stress risers, having it machined fully. Possibly I'll cut the bore and insert ductile iron bore sleeves for extra strength. I'm going to use a 1/4" thick stud girdle with ARP studs. If my budget allows it, I may do as Danno suggested and get the Milodon 4 bolt splayed main caps and put those in along with the stud girdle (if that will work). According to the Mopar Performance book, a seasoned block is already stress relieved so I don't know if I'll need to stress relieve it again after having it machined. I'm going to port the oiling system for less resistance, possibly install lifter bushings for better oiling. A valley pan and windage tray. If I can't afford a dry sump I'm going to do something trick with the oil system and get either an oil accumulator or some sort of remote oil reservoir that takes oil from the back of the valve covers and feeds it to the reservoir which is connecting directly to the oil pump. I'm a little concerned about finding a gear drive since they are very expensive, so at the least I'll run a cloyes billet double roller with the Mopar Performance timing chain tensioner. And then I'll do any other oiling system modifications that are recommended in the MP book.

Yes, on a large track I will be at a great disadvantage, but at Ventura which is 1/5th mile I should have a decent chance.
Currently I'm most concerned like MoparDanno said, about being able to get the kind of compression I need and the pistons. I'm not too concerned about the cylinder heads, I'll either get some aftermarket heads from Indy or I'll used Brodix B1-BA heads. You're not allowed to port them so I think it should be fine. Once I find out my compression ratio, the flow of my cylinder heads, etc, I'm going to contact Comp Cams for a recommendation on valvetrain and they will recommend me all the matching valve train components to optimize what I've got.
 

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Any aluminum intake can be modified with injector bungs to work. I would think a Victor Jr. Air Gap or M1 Mopar (I think that's what it's called) intake would be a good start.
 

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Discussion Starter #17
Yeah but it can't be electronic, only mechanical fuel injection. :( So I'm not sure how to find a hilborn injection set up for a Mopar, or where.
 

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Kinsler offers mechanical fuel injection of several types, as well as stacks and throttle bodys. It'd likely be easiest to work with a throttle-body setup.

Don't get me wrong, I'm no expert on this stuff, but it looks doable to me. I've always maintained that the 318 is an underrated motor (mainly because the 340 and 360 stole the show), and would love to see you have success with it. Good luck!
 

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By the time you spend the money to make the 273 crank work and then come back and redo the bottom end later...

You could easily buy a forged crank and use a more plentiful 360 block.

I understand racing on a budget, but taking short cuts should not be part of the budget. Build your engine right from the start, it will be worth it.

I'm with Danno, you may want to consider simply saving your money and picking up a Kinsler/Tony Stewart engine off Racing Junk.

Mike
 
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