Yesterday I finally bit the bullet and dropped an engine at a local machine shop to get it rebuilt. They'll give everything a look-see and cook up a quote for the labor. I've still got some decisions to make on parts. Some of which can't be decided until I get more info from the shop. But I've got a plan in mind pending more info.

Budget? We don't need no stinking budget! Seriously though, I'm thinking ~$1,000 for machine work and maybe that much again on parts when everything is said and done. Plus the cost of flywheel resurfacing, a new slave and a new clutch because why wouldn't you since the engine is coming out of the truck anyway?

First, there's the 240 head I ported over a year ago that's needs finishing and assembly. Gonna do new guides plus those fancy teflon seals all around, mill and tap for ARP studs, cut valve seats then mill flat.

I picked up a set of Elgin stainless 1.94/1.60" SBC valves (good enough for an engine that lives below ~5,000 rpm, I reckon) and I'm hoping to reuse a set of springs I pulled off a pair of worked D0OE 351W heads. They'll measure the spring height and check the springs once they've cut the valve seats. Saving $80-90 reusing springs and retainers equates to "free" ARP rod bolts and a one-piece oil pan gasket down the line so fingers crossed there.

As an aside, if you're contemplating a 300 rebuild I'd stay away from the 240 head and use a 300 head. In the case of a normal (i.e. mostly street driven truck) rebuild you can pick up all the compression increase you want with different pistons and decking the block. I'm going to end up with an engine that probably will need premium gas, which isn't a huge worry since it's going in a vehicle I only use for fun. But if it were a DD I'd seriously consider starting over with a 300 head.

The block, crank, and rods have been machined before. The block is already .040 over and needs a rebore. I'm 95% convinced i want a never-been-remachined block instead. I'll wait to see what the shop says but I've already got my eyes open for another block.

The crank and rods are .020 over but the crank looks okay maybe with just a polish. Again I'm kind of meh on them if they need complete refinishing. If I can find another cheap core I may start from scratch on the bottom end. Hate to spend all that money and end up with an engine that "only" goes another 100,000 miles.

Block selection aside, after the standard block prep they'll measure and mill to put the pistons .010" below deck. I'm going with hypereutectic pistons for a '96 EFI 300 mostly because they use shallow rings (less friction).

Those pistons at that deck height with a 240 head will put the compression ratio at ~9.6:1. With a 300 head it would be ~9.1:1.

I'm pretty much settled on the Comp 268 cam. It ought to bark pretty good when I stand on her tail and the Comp kits are a pretty good value.

That's the plan, but subject to change until the shop calls back.

 

Subscribed!! Sounds like you got yourself a great build going there bud! I too am itching to redo my head I wanna put bigger valves in it and go with a bigger cam but maybe later, next year I'm gonna take it to a shop to re-gear the differential


Good luck on the build and post pictures please!!

 

Sounds good. If you are getting a Comp Cam kit, I think springs come with it. Also, the only thing that was a bit of a bump in the road in mine was the gear set had a knock and the machine shop swapped it out and it's been peachy ever since.

 

Why not just pull the sought after ratio rear from the j/y and install new bearings, seals, fluid. That is what I did. I can now get a diff. here for about $100. I went from 374:1 to 331:1. (On the latter ratio I don't remember the exact number, but I'm close.)

I've been looking at the Super duty rear end with the emergency brake drums and disc's.

The 10.5 sterling is the rear end used in the '99 to '04 (I believe) F250/350 Superduties. It's a super tough axle, but uses the metric 8 on 170mm bolt pattern which I changed to 8 on 6.5". Since the brakes are a factory setup they have mechanical mini drums inside the "hat" of the rotor for a a parking brake. As small as they are they actually hold my truck on a good hill and will also stop it eventually.

 

Good luck with your rebuild. Its a great bit of fun. The only thing I can recommend is put it together yourself. The shop I use here locally decided to "give me a break" since I've used them for over 20 years. They assembled my short block and that was a huge mistake. To make a long story short, There is no better quality control then yourself. I guess I'm **** but I want it right.
The only other thing I had a problem with was the "high performance" gear set knocking at temp. Seems the slots cut in the back of the cam gear to clear the retainer bolts are just a bit too beefy. Mine would heat up and sound like a rod knock. A few passes with a bench grinder solved that problem.
Keep us informed and updated!!!

 

That's what I wanted to do originally is pull the gears and carrier from another housing at the j/y I've come by a lot. But on summit racing they sell a whole kit that includes just about everything for about 525 bucks, At this point I dont mind about how much I spend as long as it gets done and done right. Ive seen a couple disc brake conversion kit for my rear end but that may be later in the trucks life.

 

Quite a few members report problems with the gears that come in rebuild 'kits.' If I swap my cam, as I'm considering, I would use only a Cloyes set.

 

That's what I used. The problem in my case is that the machine shop obviously couldn't find the original cam retaining bolts and substituted cap screws which were just a tad too high. Like I said, not a huge deal but attention to detail is what I'm talking about. If I had disassembled completely then reassembled the short block, it would not have been a problem.

 

Subscribed

 

Popped back by the shop today to check up.

I just had the shop order some rocker studs, they're on the way and they'll cut the pedestals and tap the threads. Other than that the head is ready to assemble and check if the springs I have will work. I forgot to check if they resurfaced the gasket face.

After some discussion we decided to punch the block out to .06" over. I trust them and they say no worry. The block is prepped other than resurfacing and rechecking the deck height. They'll call to confirm that before I order pistons.

With waiting time for parts I figure three weeks until it's even close to being ready to go in the Bronco. I may splurge and have it dyno tested just to see how it stacks up against the Powerblock TV guys.

Parts list for those keeping score:
http://www.summitracing.com/parts/cc...48-4/overview/
http://www.summitracing.com/parts/ue...-060/overview/
http://www.summitracing.com/parts/ar...6001/overview/
http://www.summitracing.com/parts/fel-1024/overview/
http://www.summitracing.com/parts/fe...601r/overview/
http://www.summitracing.com/parts/fe...028r/overview/
Ford 240 300 4.9 liter 6 cylinder engines Cylinder head bolts / fasteners

 

[QUOTE=BaronVonAutomatc;13969293]Popped back by the shop today to check up.

I just had the shop order some rocker studs, they're on the way and they'll cut the pedestals and tap the threads.

I did that too. I sheared off the top of two of the studs. I was on the freeway and only the big guy up stairs kept that valve from dropping. Now I use ARP studs for a sbc, $50 more or less.

Also, I love the way the 268 cam sounds, but really, they should relabel it and raise the operating rpm from 1200 on the bottom end to 2400 rpm. It cracks me up how cam co's do that.

 

If I may....mind sharing machining prices?

For decking, overbore, magnafluxing, shave head, and install cam bearings and freeze plugs I was quoted $470 from the Carquest machine shop.....seems about right remembering a 318 I built probably 7-8 years ago.

Thanks!!

 

I have a theory on the 268h cam contrary to the popular wisdom.

When you look at the cam card vs. the stock 300 cam (someone was kind enough to degree the stock cam over on the FSP big block six board) the valve timing is exactly the same except the Comp cam is advanced 10°. Both have 268° advertised duration, both have the same LSA @ 110°, but the ICL on the Comp is 106° vs. 116° on the stock cam.

So the intake valve actually closes 10° earlier with the 268h vs. the stock cam. In theory - because earlier intake closing decreases the air that can flow at higher rpm and increases dynamic compression ratio - it should actually move the engine's power down in the rpm range and increase "low end" power.

From a practical standpoint it's like advancing the stock cam 10° and using ~1.85:1 rocker arms. In the big block six FAQ at FSP their recipe for the ultimate low end 300 is to advance the stock cam 8° and use 1.75 Chevy rockers.

So I expect the 268h will idle fine ~650-700 rpm like the stock cam but have even more grunt off the line. We shall see.

 

For sure, I'll share once everything is all done and I've ponied up the dough.

 

Dropped off the rod bolts and caught up with my machinist. The block has been decked .010 before, so no worries with the pistons sticking above deck. He's going to measure once the pistons are in hand (finally ordered parts today now that I know the deck height) then put the pistons ~.006" below deck.

So a couple of weeks from having the short block ready to go.