351W Twin Turbo
(Crazy Joe's Budget 351W Twin Turbo, Intercooled, EFI Mustang)
Mods for 2001
Crazy Joe's stock/unmachined 351W short block had finally failed after two years of abuse (one in the SCTC, one in CJ's TT). We were on our way to a local car show (yea I know you're all laughing now, but it's true), cruising on the expressway when we first noticed the slight knock. By the time we reached our destination, it was hammering pretty good and oil pressure was dropping. After making the decision that we'd rather be safe than sorry and risk the chance of damaging one of our JY turbos, we sent my brother Dave back to the house to fetch the trailer.
Here is a shot of the upper main bearings that are out of CJ's car, the copper seen here is actually from the lower bearing wear and deposited here. Unfortunately I put the lower bearings in a safe place so I'd have them when I got around to taking pictures....but can't remember where that safe place is - go figure. We've been finding that bearing life is about 2 seasons in these stock 351s with a reasonable amount of boost (12-15 psi).
In order to get the engine ready for this season we had to start by getting the crank fixed. The mains cleaned up with 0.010" removed, but since it was a rod bearing that spun, it needed to go to 0.020" on the rods. In an effort to add some extra durability, we switched to a set of 351W truck rods and had them resized to ensure round big ends. The block was bored 0.030", zero decked, and line honed by Dave Straley (Straley Racing) to make sure everything was squared up. A high volume oil pump driven with an ARP drive rod hopefully will keep all of the spinning stuff lubed and happy.
The pistons are sealed power hyperutectic pieces, we would have liked to use a low cost set of forged pistons but could not find anything suitable for this application under $200 (CJ's limit). This is my first time using hyperutectic pistons - we'll just have to keep a close eye on the tune and stay a little on the safe side, a heck of alot easier said than done... Finally we slipped the new flat tappet hydraulic Crane Cam into the short block and checked it's position. It degreed in about 1 degree retarded from where I specified, but that's probably due to the timing chain which has been used for one season. We'll run the engine as it is and then make a decision of we want to move the cam a little or not.
Once the short block was buttoned up, dad went right to town installing the heads. Were using the same Iron GT-40s that he used last year with one exception, we replaced the stock valve springs with a set of Crane Cams conical springs normally sold for use with the 5.0 roller cams. These spring kits allow you to use cams with as much as .560" lift yet still retain the stock ford valves with different keeper groove heights. All 5.0 stock and GT-40 heads (not equipped with stainless valves) use different keeper groove heights on the intake and exhaust valves.
Next up was the intake manifold, I did port the lower intake, but not quite to the size of the gasket, as you can see on the photo to the left, the intake ports on the head have had flash removed, but have not been gasket matched. I just tried to make the intake manifold match the port as good as I could and we bolted it on. I'm sure there is more improvement to be found in porting these GT-40s, but with the amount of time involved, we decided to bolt them on and keep an eye open for a used set of aluminum heads to work on instead. These heads have already run a best ET of 10.73 on Drag Radials with a very mild tune, we think they should still be good for mid to low 10's this year on slicks with some additional tuning.
On the left is a shot of the Summit SFI balancer that moves us one step closer to being legal for the speeds that this car is capable of ;). On the right is a final shot of the bottom end just before buttoning up the oil pan. As you can see, there is nothing special about this engine, with just a couple good parts in the right places you have a 10 second capable twin turbo engine.
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