360 - Rebuild - Information & Opinions Needed

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JRapley

JRapley

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Just picked up a 79 Lil Red Express (I know, I know, not an a-body :eek:) and am planning on taking the engine out this winter and either rebuilding as stock, or maybe hopping it up a bit. The whole reason the engine's coming out is because she's tired and at least needs a freshening up.

The engine is the E58 spec 360, all stock minus a new Edelbrock carb.

If I plan on hopping it up my goal is to just have a little more kick from the engine for more fun. Nothing for racing, nothing fancy, just more of a 'budget' build I guess.

So, keep in mind, I'm a total newbie when it comes to cam specs and what works best with what, so all suggestions and information are more than welcome!

I was thinking of putting in a better cam, getting the deck height milled down for a little more compression, cleaning up the heads, better intake and installing headers.

So, my questions are:

1) What amount is safe to mill off the deck?
2) Will there be valve interference issues with a lower deck height w/stock heads & cam?
3) What's a good cam to upgrade to? From what I've read the stock cam is a '68 340 cam.
4) Best intake choice on a budget?
5) Are all these mods not worth it if I don't get some head work done?

Thanks in advance for all advice and input. If I'm totally out to lunch let me know! I enjoy the learning experience.
 
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Hop up on a budget?

Stock carb is good, the edelbrI I is fine.
The cast iron intake is a very good one.
Leave the heads stock. Just use the matching valve springs to the cam which I'll get to In A second.
Mill the head only to make them flat on the bottom. Don't bother with a valve upgrade. Stock valves will do well. No port work.
Ke Th Black or Speed Pro make Hyperutecic pistons at good prices for increased compression, but you'll need to do some math work on IF the deck needs to be killed down for a good ratio. 9.5-1 is the MAX! I'd do with iron heads and a small cam.

The 340 cam is OK but I like the upgrade 340 cam. Similar advertised specs, a bit different at .050 lift. This will not interfere with the pistons at all. Stock or aftermarket.

The '68 / 340 cam is a 4spd trans cam. It is a good cam but rarely seen made.
 
Only deck the block to square it up. KB 107's will give you around 10:1 (.011 in the hole), Speed-Pro H116CP30 around 9.8:1 (.026 in the hole).
Comp 268AH-10 cam, Heads stock, Intake stock, headers, 32* total timing all in by 2800. Some 3.55 & factory or aftermarket hi stall converter
around 2800 rpm.
 
After thought....

IF you do not want to change the torque converter out for a higher stall, then I suggest a of no larger than [email protected] duration.
Cam selection is also dependent on vehicle weight
Tire size
Gear ratio
Torque converter stall
Intended useage of the vehicle

You have told us the vehicle and its intended useage and we will assume stock tire size.

IF you know the trucks tire size and gear ratio as well as IF you are OK with changing out a torque converter, then that would help a good bit.
 
Thanks for the reply guys, good info to start with. I'd have to double check tire size when i get home.

I know the stock rear end is still in it, so a 9-1/4 with 3.55 and the stock stall is 2500. 6050lbs weight.
 
WOW I didn't realize those trucks were that heavy.

I'd give Dave Hughes at Hughes Engines a call and pick his brain.
 
EDIT: my mistake on the weight, I knew it seems ridiculously high, going through the charts I obviously got the wrong column, should be a curb weight of 3815lbs.
 
I'd put pistons in there that at least attempt to put the crowns into the open chambers, like the 340 pistons did.Or a swap to closed chamber heads, and zero deck pistons.I'm not a fan of decking the block for compression, but rather getting the piston crowns up to the existing deck,instead.With 3.55s it's gonna be a long pull to redline in first gear, so no sense in putting a big cam in there.Nor much sense in hi-rpm head work.I would concentrate on getting the Scr/Dcr just right.
On the other hand if an O/D tranny can be fit relatively easy, and 3.91s or better,are on the table; that would be a totally different engine.Ima thinking 4.30s and a 2.45-1.45-1.00-.69. That would be a starter gear of 10.54, a trap gear of 4.30 and a cruiser gear of 2.97, BaBam!
This should easily get you 106 mph in the qtr at 325 hp, which is a pretty mild build. And it will cruise at 2400@65 with 27s. And it will boil the hides through two gears or to at least 60mph.
As to ET, nobody can say cuz that will depend on your tuning skilz and the amount of money you put into the suspension. But I can tell you that the Direct Connection race Bulletin#40 says that 106 can be mid to low 12s.
325 is easy on a 360, with mostly bolt-ons, and a little attention paid to compression. If you are a little careful you can push 350 plus, even 400, cuz high-rpm is back on the table. If mpgs are important to you,a tight squish and a good cam has been recommended by Rumble, but then think closer to 300/325 hp, which will still be whopping big fun with 4.30s. The 218 cam will make a mountain of torque and so 3.91s might be the ticket(depends on your tire size), which will put your Rs to under 2200 with 27s @65. Your Trap speed might suffer some and your ET will suffer for sure.But your Mpgs will be up. The 3.91s might also require a bit of a TC to crank off the line, it's hard to say; that 218 is some nice off the line with a 4-speed and 3.55s(10.97 starter) , so 3.91 x 2.45=9.58, plus say 5% minimum in the stock TC is an equivalent starter gear near 10.06, so I imagine an 1800 TC (about stock) would be pretty peppy.
Anyways I'm just dreaming about what I would do...
 
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While that GM tranny is a sweet install, the ratios are just a bit wider, and my thinking was a 518.
I don't know what the LilRed looks like underneath, but it can't be too different from my 84D100, and it's looking pretty roomy under the old D. The 518 looks like a pretty easy project.
 
Firstly, tire size is 275/60R15, just so you guys know a little more info.

Thanks for all the info guys, this is definitely A LOT of info to take in, especially for a newbie to engine building. Please bear with me if some of the questions seem silly or too simple, but I'm still getting the basics of it. Guess you have to start somewhere!

If I tear the engine down, send it to the machine shop to get hot tanked and checked over. Get a couple thou. taken off the decks to square them up, and get a couple thou off the heads to get good and flat, could I purchase the KB107's w/ring kit ( https://www.summitracing.com/int/parts/uem-kb107ktm-std/overview/make/dodge), re-use my connecting rods and crank (w/new bearings), use these head gaskets (https://www.summitracing.com/int/parts/mrg-1121g/overview/make/chrysler) and get a good bump in compression with the stock heads?

@DARTH V8R, when you refer to 0.011", that's the distance from the top of a KB107 piston to the deck, correct? Also, I believe the stock heads are 66cc, but that could be different for the cop heads? The Comp 268AH-10 cam, after looking it up it's the stock PN for 383 & 440's, this shouldn't be an issue in a 360?

@rumblefish360, what's the upgrade 340 cam? When you advise for no more than 218 @.050", how does that compare to the stock cam's 252deg duration? Is that listed at a different point, or am I confused and thinking of two totally different numbers.

Thanks again, I appreciate all the help
 
JRapley said:
when you refer to 0.011", that's the distance from the top of a KB107 piston to the deck, correct? Also, I believe the stock heads are 66cc, but that could be different for the cop heads? The Comp 268AH-10 cam, after looking it up it's the stock PN for 383 & 440's, this shouldn't be an issue in a 360?
Click to expand...
Yeah .011 is the deck clearance. 383/440 cam will be a huge problem lol. Sorry I shoulda posted a link with it. 340 cam: http://www.compperformancegroupstor...Product_Code=20-309-4&Category_Code=LACAMHFMM
 
Are headers in the budget? I'd put those on and have the exhaust built to reach the vertical exhaust and let that motor breath. One other thing to mention, i'd measure the cc chamber volume of your heads to actually be sure before ordering pistons to put your compression ratio where you want it instead of what volumes are commonly published on the net. The 360 heads I have and are currently porting, chambers measured at 78 cc's with the stock 1.88/1.60 valves. Most of my books list them at just 68-70.
 
@racerdan80, headers will be in the budget. From what I've read the TTi a-body headers fit great without clearance issues, and I'll definitely be going to the stacks.

I'll have to take a quick look around and how to calculate chamber volume, I'm assuming it's not too much of a process once the heads are removed?
 
Go to the section "mopar general discussions", at the very top in the sticky's is "how to's", 3rd post is a link for compression check. The post is by Krazykuda, very detailed and well written. Also youtube is at your disposal.
 
Just re cc'd my 360 heads. Casting 4343475, dished intake valve alone measured 2.25 cc, chamber with valves and sparkplug installed 78.25 cc

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Yep, mine are 80's smog heads. The book How to Hot Rod Small Block Mopar Engines list them as 66.0-72.5 cc's. And yet mine measure at 78. That is why I recommended to the OP to measure his heads to be sure what he has before he buys any parts. Otherwise his combination will be disappointing and a waist of money
 
Well now. I also cc'd some 3671587 smog heads, they were around 71.5cc on average. Interesting that the 80's heads (well at least in your case) chambers are larger.
 
It's easy to overthink things. If the goal is budget build, and cruising/fun then I'd replace the pistons with KB107s and internally balance the thing. If it were me I'd also align hone the mains and square deck the block. Those with a modern hone and wall finish will give you some power and economy. On the heads - have them rebuilt and expect to do exhaust seats and guides, replace the valves, and have the guides and spring seats cut. The valve job is critical. Have a modern 5 angle "cutter" valve job done. That basic blueprinting work will also add power and economy regardless of the cam choice. You don't need aluminum, nor do you need porting. I agree with the "keep it under 220° @ .050" crowd. You don't need a ton of cam. It will be plenty quick and torquey and run good on pump fuel.
 
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