Truck motor build, please advise

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V8-valiant

V8-valiant

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Hey guys I'm going to be putting together a 360 for my truck, it will be used primarily for towing. Just looking for so opinions on a decent motor that is reliable with a fair amount of power. It will consist of a 360 with some 107's and 587 heads I will be decking the block to zero and should end up with about 9.8 compression. I will be running a air gap and a 670 Holley on it. I'm just kinda looking for ideas on a good can for low end torque also wondering if I should do any head work (very light porting) or just keep them as is. It's going in a 1970 dodge 4x4 with a 727. Tall gears and tires.
 
try a 318 magnum motor with a carb. most have zero cylinder wear so you can do a ring and bearing. Reason I say 318 vs 360 is 318 in neutral balance. make a nice motor for 4wd for cheap. the stock magnum cam works good
 
9.8:1 with iron heads in a truck meant for towing?
 
hell with it...why not...

I would probably build the 360 with about 9:1 SCR, do port/bowl work on the heads to bring up the low lift numbers, run a cam with 110 LSA, < 265-270* advertised duration, about 220* @ 050* and lift numbers to make your head flow really work for you...probably about .500" lift...the low lift big number stock heads often stall out above .500", so after that you're not helping yourself. Dual plane intake port matched to your heads, 1 5/8" long tube headers into dual 2.5" exhaust, turbo or similar type mufflers to keep down the drone...mild 2200-2500 stall to get it moving, with gears appropriate to match your desired towing speed/RPM...probably a 3.73 or possibly more for your tall tires...?

I'm sure my suggestion will be shot to ribbons in short order, but at least its a direction to deviate from.
 
I guys I should have been a little more clear before I got the "smart" remarks. Im just looking for advise on suggestions. This is an initial though based on what parts I have and can put together a motor with. Also why I posted here to get an idea what help I can get from those who are willing. I have ordered everything for the trans already from John cope he's got a 12" towing specific converter and will also be going through the trans and vb. the truck has a 4.10 ratio and has 35" tires. I've got long tube headers and will be running similar exhaust. The reason I mentioned 9.8 compression is because I want to be sure it will do the job. I'm not in the flat lands of Florida. But guessing you guys are concerned about detonation?
 
The reason I mentioned 9.8 compression is because I want to be sure it will do the job. I'm not in the flat lands of Florida. But guessing you guys are concerned about detonation?
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Using old school open chamber heads with less than ideal mixture turbulence, pushing a fullsize pickup, towing often, on varying grades, fed on pump gas--yes. You can do it, but you might need to run a slow and shallow timing curve.

What smart remarks?
 
My truck has it's original 57K mile 360 (1987 vintage) with an XE262 cam in it. I love it. If you plan to go with the KBs I would NOT zero deck them. In fact a better piston might be a little shorter to keep the static low, and run a conservative cam. My truck never spins past 4500 and typically runs from idle to 2400. Cruise is 2900 at 70. If your cam is giving a torque peak higher than your cruise rpm it's wasting fuel when you're not right at it. You want something that makes peak torque down low an dpulls off idle. And do it with the cam - not compression.
 
We ran the Crane stock 340 replacement cam with Rhoades lifters in our Warlock II with a 360 and it had nice grunt and better MPG than factory.

I would stay in the 260° - 270° duration for a towing motor...

The XE262 would also be a good choice...
 
If I was building a engine for truck to tow with I would go with 408 stroker kit in 360 magnum block, cast crank, KB KB356 piston, stock rods with ARP bolts as far as a camshaft-HYD 214 224 duration @ .050 Adv Duration 288 298 -valave lift.443 .466 Lobe seperation INT108 EXH 116 2000-4800 power range
 
Thanks for the feedback. Trying to keep it a budget build, that's why I would like to use what I've got. I understand everyone these days wants everything for nothing. So I will change what I need to get it right. I was looking at the comp xe cams and based off what I anticipate the engine will turn for RPMs I was kinda looking at the XE250 or XE256 they have low power ranges 800-4800 for the 250 and 1000-5200 for the 256 but they are both shy of the 260-270 duration I'm being suggested. Am I going from one extreme to the other?
 
I am putting a 360 together for my 87 2wd pickup.Starting with a reman 1984 longblock(has 915 J heads).Measuring everything to find actual compression before I pick a cam.Going to have my machinist check it all out and do a little bowl work and check the valve job(maybe back cut the intake valve).May mill the heads and/or the block a little as I would like to see 9.00-1 but this may be a stretch.
I have a used Edelbrock performer intake which I will port match to the 360 heads.I also have some used coated long tube headers for it.
Not sure on carb but I have many here with the smallest being a 750 vacuum secondary or I can rob the TQ of a smogger 440 eating grass.

I have one guy recommending the old comp 268 HE cam,my machinist wanting to with either the comp XE262 or XE268 and I am wondering about the Hughes Engines SB HYD FLAT TAPPET CAM 220/224 -111ºLSA .503/.518 or one size smaller on a 112 if I can sneak by with the stamped rocker arms.
 
V8-valiant said:
Am I going from one extreme to the other?
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Your mistake's a classic one that's getting pretty common. If you try to run that compression with open iron heads and a small cam you'll not only have a truck bad for towing, it won't drive well either. If the compression's gonna be that high it'll need some more cam to it. Yes it will detonate, and if it does it will be next to useless even as a street truck without a load. Due to loads you may end up having, I'd never aim a tow rig at running premium gas even if it always will- it should be able to run cheaper gas in case it ends up getting some as premium so it'll still run acceptably.
 
JMO I would just build a STOCK 383 or 440. You will have torque for days. MT
 
1) Leave the block alone, do not deck.
2) cam choice 260° pick a company, Crane, Comp or whoever. Hughes cams are a favorite of mine, but not cheap. Plus many need special springs, remember your budget.
3) Factory iron intake. An iron intake will be fine for your application, plus, in 5 years there will be no galvanic corrosion at the back of the intake over the water jackets.
4) Dual exhaust with 2.25" pipes and an "H" crossover. Dual 2.25" is more than enough for a 360 turning less than 4800rpm. If you go big pipes, velocity will be lost. Mufflers that do not drive you crazy with drone, suggest Dynamax or similar.
5) Electronic Distributor: recurve, with max 32-34°
6) Phenolic insulator under carb since you are using an all metal carb.
7) Make this 87 octane friendly!
8) Skip the head porting
You want this truck to start with the touch of the key, never complain about the octane of the fuel, not have any mismatched components that fight each other.
Do lots of research before you buy.
 
Best bang for the buck is a low mile 5.9 magnum from a wreck. By a carb intake, buy a camshaft snout extension and change the timing cover over to the "la" style. Cheaper than building a motor, can do the whole swap in a weekend.
 
V8-valiant said:
I guys I should have been a little more clear before I got the "smart" remarks. Im just looking for advise on suggestions. This is an initial though based on what parts I have and can put together a motor with. Also why I posted here to get an idea what help I can get from those who are willing. I have ordered everything for the trans already from John cope he's got a 12" towing specific converter and will also be going through the trans and vb. the truck has a 4.10 ratio and has 35" tires. I've got long tube headers and will be running similar exhaust. The reason I mentioned 9.8 compression is because I want to be sure it will do the job. I'm not in the flat lands of Florida. But guessing you guys are concerned about detonation?
Click to expand...

Where were the smart comments?

And no, "I" am not concerned at all since "MY" truck has 8:1 compression.
 
replicaracer43 said:
Best bang for the buck is a low mile 5.9 magnum...buy a camshaft snout extension...
Click to expand...

I can't disagree with using a 5.9 Magnum as the base for a towing engine--a good friend of mine used to have one in his '01 Ram, but I'll part ways with ya on that cam snout extender nonsense...that damn thing only cost $30 to buy, but then it has to be machined to work correctly...and that effectively doubled the cost of a spacer, a key, a cup washer, and a bolt...if I had it to do over again, there is no way I'd use that product or recommend it to anyone I valued as a human being.
 
The advance curve is your best friend for towing in the Pacific NW.
A standard edlebrock performer topped with a Holley 600.
Lunati 60401 [email protected] 454 lift int. 220@ .050 474 lift exh.
 
txstang84 said:
I can't disagree with using a 5.9 Magnum as the base for a towing engine--a good friend of mine used to have one in his '01 Ram, but I'll part ways with ya on that cam snout extender nonsense...that damn thing only cost $30 to buy, but then it has to be machined to work correctly...and that effectively doubled the cost of a spacer, a key, a cup washer, and a bolt...if I had it to do over again, there is no way I'd use that product or recommend it to anyone I valued as a human being.
Click to expand...

I have t wonder why you had to machine anything to make it work? The first one I used was 10 years ago, bolt on deal no issues, probally used the exact part from hughes engines 5 or 6 times since.......the last one was about 2 months ago on a friends 5.9 swap. Maybe you got a bad part or something?
 
Back in the late 80s I did a basic freshening up on the 360 in my 75 Dodge B300 van, rings, bearings, oil pump, valve job. While I was at it I put on a factory TQ manifold with a spreadbore Holley, Cyclone headers and a Crane RV/towing cam. The trans and converter were stock and I had 4:10 gears in the back.

The cam had a powerband of 2600-3500 rpm. 70 mph was around 3300 rpm. I did a lot of highway towing then, so this worked out great for me, more power where I needed it and even slightly better mileage. Previously the van always got 9-11 mpg, 9 while towing, after the changes it got 11-12 mpg even while towing.
 
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