360 rebuild, some questions/infos

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MoparFan

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Hi,

so I have my old 1978 360 on the stand in the garage now, and don't exactly know what to do with it !!!

I removed the head, and check some things ... as well as a novice can do. Now I wonder if I should give it to a rebuilder and spend the 2500$ or more it will cost me for a warm over engine.
Or is there something that I could do by myself without changing everything, to give him life. I mean if I rebuild it myself (would be my first try ever ... good idea, not so sure), the block would go to the machine shop to be check, cleaned, bore over if necessary, have the crank and cam alignement check and bearings changes, maybe a block and head shave also.

Maybe I am very wrong to think that I can do any thing close to a performer with stock piston and head, but how wrong am I.
Can an engine like that produce 350hp, with stock piston and head (milled?), an Holley street dominator intake, an Holley 1850 600cfm secondary vacuum carb, and probably a cam change. Would use a set header as well.

What I am looking for is a fun engine, that can burn tire on a open 8.25" with tall gear (for now at least). Just want to have some fun with the car before investing too much money in it.

Rigth now the piston is down in the hole by 0.100" ... here is a pic of the piston (flat ? I guess not!)
piston.jpg


Thanks and let me know what you think
 
I have a 78 360 in my 69 Barracuda, and had it milled and short block assembled by the shop, along with the heads milled and 2.02 int and 1.60 ext valves installed.

I went through the same thoughts that you are.
Here is what my thinking was.
For $2500 I now have an engine that with the addition of closed chamber heads and hotter cam should produce over 350 hp.

Spend the money upfront to either re-build the engine yourself or have the shop do it. I don't think you will be happy with the results if you keep the stock pistons and do nothing to the heads, and the shop labor will be about the same. So have it milled and the heads either milled or buy some aftermarket heads. I ended up spending a lot of money on my stock heads and for $400 more I could have gotten some Edelbrocks.

Currently the engine has the following
Speedpro HP116c pistons .030 over
New Clevitt bearings
MP 260 268 cam
Polished Crank
Stock casting heads with 2.02 and 1.60 valves 68CC chambers and ported
And a bunch of other stuff
Comp ratio 9.2

Now if you look at the end result for $2500 you can see that a short block crate engine is not to far off. If I had it to do over again, I would think about a crate engine. But that is because I have already had the experience of building my own engine. I had never done this before, and the experience was well worth it, but if I ever need another engine, I would look at a create 360.

valentek
69 360 Barracuda
86 360 Ramcharger
05 Sebring TSI
 
If i were you! I would get me a real good book on rebuilding mopar small block engines! Find a Mechanic that you can pay to come over to assist you.But mainly you do the work.Have the heads freshened up,maybe even have a little extra done to them,have the engine block checked at a machine shop and only bore it if it needs it. You should be able to do this and come out with a nice little engine for less than $2500.00. Ask around and you can probably find a mechanic to help you out or even another Mopar owner that has engine building experience.But if you know nothing at all about mechanics,and are not very mechanically inclined i would just find a reputable shop and get it done. But it really sounds like you want to gain some experience so go for it.There are different builds you can do and for $2500.00 you should be able to build a nice little engine.For performance focus on Heads,Cam,Intake,Carb.You will gain some performance if you bore the engine and change pistons to raise the compression a little.Ask a couple different shops for some advice.There are some nice books out that tell you exactly what to do to get the HP,even gives you part #s and everything.I say go for it and gain the experience,you will learn a ton and have some fun in the process.And If you get in a bind people on the board here are always willing to help with answers.Maybe even a board member lives not far from you that might want to help out for a few $$.

Bobby
 
Was this a good running engine? It doesnt look too bad. My own version of "cheapest" should run about $1500-$2000. If the bores are good, meaning no rust pits or bad scratches, and the engine was running before so you know it's not cracked. It's very easy to spend a lot to get everything perfect. It's sometimes better to leave "well enough" alone. I dont like installing new bearings on a used journal. Your horsepower is very reasonable, and can be reached safely with nothing more than factory machining and a cam change. So my build would be a crank kit (crank and mains and rod bearings), file-to-fit moly rings, cam bearings and block hardware, and the usual oil pump/pickup, good timing set, cam, lifters, nad I'd replace the rockers with MP thicker stampings, but I'd clean and reuse the pistons and rods as is. For machining, clean the block, deck it, and have it honed for the right finish with moly rings (that's much smoother than a typical ball or flex hone). Spend the money on having the heads completely redone. Guides, seats if needed, valves, the works. Add good springs, have the guides trimmed for teflon seals, and give it a good set of valves. Dont worry about adding compression any more than using MP thin head gaskets. Stick a Comp Cams XE268, and I'll bet you can go pretty well beyond the 350hp level, and more importantly, you'll have great torque and it will run on 87 octane. That's how I'd do it.
 
Thanks for the all the advices...I will continue to think at all the things you said, and see what I will do.

moper said:
Was this a good running engine? It doesnt look too bad. My own version of "cheapest" should run about $1500-$2000. If the bores are good, meaning no rust pits or bad scratches, and the engine was running before so you know it's not cracked. It's very easy to spend a lot to get everything perfect. It's sometimes better to leave "well enough" alone. I dont like installing new bearings on a used journal. Your horsepower is very reasonable, and can be reached safely with nothing more than factory machining and a cam change. So my build would be a crank kit (crank and mains and rod bearings), file-to-fit moly rings, cam bearings and block hardware, and the usual oil pump/pickup, good timing set, cam, lifters, nad I'd replace the rockers with MP thicker stampings, but I'd clean and reuse the pistons and rods as is. For machining, clean the block, deck it, and have it honed for the right finish with moly rings (that's much smoother than a typical ball or flex hone). Spend the money on having the heads completely redone. Guides, seats if needed, valves, the works. Add good springs, have the guides trimmed for teflon seals, and give it a good set of valves. Dont worry about adding compression any more than using MP thin head gaskets. Stick a Comp Cams XE268, and I'll bet you can go pretty well beyond the 350hp level, and more importantly, you'll have great torque and it will run on 87 octane. That's how I'd do it.
Click to expand...

As far as I know the engine was running when it was top 5 or 6 years ago. Before we removed it from the car, we cranked it and pour gas in the crab ,and the thing was trying to fire up and run on is power ... but did not do it (my guess is either the carb or the lean burn or both)
I was wondering about the machining of the deck. What is the maximum that it can be machined? Can I have it zero deck with the piston so far in the hole? How much to remove from the head?

Thanks
 
I'm not sure if you can mill the block that far. (I forget these things because there on paper somewhere.) But I do like mopers idea.
The Fed-Mougal pistons are a good deal. KB also has a set @ around 200 and less bucks. I like the Fed-mog's for the coated piston skirts.
A basic rebuild with ethier piston would be a great start.
The new piston is taller for increased compresion and without milling the engine block or head. This is good not to do if you can avoid it. It makes bolting on parts easier, later.
From there it is just a cam selection and carb. Preped stock heads will do well.
 
FWIW,

I had the machine work done on my 360 at a shop that specializes in performance work so they weren't the cheapest but are a top notch machine shop in my area. The cost to have the block cleaned, magnifluxed, bored, decked, the mains check for alignment, the crank ground/polished 0.010 under and the rotating assembly balanced was $1300.

Parts were $950. That included all bearings, gaskets, pistons (KB107), rings, oil pump, cam, timing set, lifters, valve springs and Eagle SIR rods.

Depending on how much you want to invest in the heads (I used stock magnum heads and I have ~370HP) you will have an engine that will easily put out over 350HP and have a bottom end that will easily support over 400HP.

The best thing you can do for a stock 360 is get the stock pistons out of it. The KB107 or the Sealed Power pistons mentioned will allow for a zero deck block with minimal machining to the block.
 
dgc333 said:
The best thing you can do for a stock 360 is get the stock pistons out of it. The KB107 or the Sealed Power pistons mentioned will allow for a zero deck block with minimal machining to the block.
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well said. Milling creates issues you dont need to deal with, and you will spend more than 2/3 the cost of those pistons fixinf the issues you create by paying for the extra milling.
 
moper said:
well said. Milling creates issues you dont need to deal with, and you will spend more than 2/3 the cost of those pistons fixinf the issues you create by paying for the extra milling.
Click to expand...
And back at ya, well said.
Build it with a taget in mind andtry to get there with the right parts the first time. This will save headaches later.
 
Thanks again for these great advices. :thumbup:

Well I guess I am not the only one like that, wishing to have that kind of thing done in a short time and for the cheapest as possible. I almost did not use the car, because of the lack of time and the lack of fun of the 318 that is tired :sleepy1: . I was hoping to be able to do a fun engine for 1000$ :error: :lol: Thanks for pointing a more realistic cost, at least I won't plan on a budget of 1000$ ! (I am a real newbie I guess)

I am kind of debating with myself to rebuild the 360 completly or at all. You know the way it works: "Bah, I already put new pistons, ring, cam and crank bearing, new camshaft, new valves train, I migth as well put new timing chain and ... and ... and... $$$$" and then blow the 904 and the 8.25" !!! :banghead: :toothy7:

I may just have to do the rebuild on a longer time period, but do it rigth, and not try to save $$$ and cut corners at the wrong place.

Thanks
 
Hey ... just got an offer for a set of 8 pistons Keith Black KB107 0.030 over with the pins ... for 250$ cnd, never use still in the box.
From what I have seen it looks like a fair deal, what do you think? Does the pins normally come with the pistons?
http://store.summitracing.com/partdetail.asp?part=UEM-KB107-8&N=700+115&autoview=sku
I don't see anything telling me the pins are coming with it, are the pins expensive?

Well maybe if I am lucky I can build it slowly gathering some good deals...

btw is these parts good quality and a good deal in your opinion:
MP Gasket Teardown Kit
MP Block Hardware Package

thanks again
 
Why the Street Dominator and Holley 1850? A performer RPM and 3310 would be better suited to a mild 360. The Street Dominator is a single plane intake and will give up some low RPM response compared to a dual plane. So unless you already have one, or have a severe traction problem, you may wish to reconsider. And while an 1850 is a fine carb, its really only going to support 275-300 horsepower even with the SD's open plenum.

Piston wise, the KB's will go a long way towards boosting compression without excessive machine work. Plan on having the bores redone as well as having the crank resurfaced. Balancing the rotating assembly is money well spent.

Here is merely a suggestion:

KB107 pistons .030 over (you really should redo the bores)
Moly rings (note the KB specs a larger top ring gap due to high placement)
Crank resurfaced .010/.010
Balanced (if you even THINK you may ever take the car to a track invest in an SFI approved flexplate and damper and have them balanced as well, torque converter too).
Stock rods resized with ARP bolts.
ARP main cap bolts
New stock volume oil pump
New double roller timing chain
Comp XE268 K-Kit
Stock heads with Ferrea stainless 2.02/1.60 valves (generally found on eBay for decent price), new guides and a good multiangle valve job.
New HD stamped rockers, new HD retainers, and pusrods as needed.
Performer PRM (non-airgap) intake.
Edelbrock 1407 (or Holley 3310) carb
Decent ignigition system (decent doesn't always mean expensive)
Torque converter with 2400-2800 RPM stall speed
TransGo TF2 shift kit
Headers and dual exhaust.

Something along these lines will be reliable, run on pump mid-grade, have decent street manners, and make a Dart scoot for well under $5000 USD. Given your taller gearing, you may wish to consider a slightly milder cam/converter. OR just learn how to walk it out of the hole and add 3.55's and a SureGrip down the road.

I'm sure the Magnum/Eddy head camp will weigh in, and it is well worth your while to consider this option. There is something to be said for all-new, high flow parts out of the box.
 
It sounds like a winner, expect I would put a high pressure spring in that stock oil pump. After you get 3.55 gears or even 3.91 depending on offen you drive on the freeway you can swap intakes and see what you think is better.
 
The stock heads will work fine with the cam and build. The more flow the better, but not the end all.
 
MoparFan said:
Hey ... just got an offer for a set of 8 pistons Keith Black KB107 0.030 over with the pins ... for 250$ cnd, never use still in the box.
From what I have seen it looks like a fair deal, what do you think? Does the pins normally come with the pistons?
http://store.summitracing.com/partdetail.asp?part=UEM-KB107-8&N=700+115&autoview=sku
I don't see anything telling me the pins are coming with it, are the pins expensive?

Well maybe if I am lucky I can build it slowly gathering some good deals...

btw is these parts good quality and a good deal in your opinion:
MP Gasket Teardown Kit
MP Block Hardware Package

thanks again
Click to expand...

The KB pistons come with pins and they also come with spiral locks if you happen to be using them with rods that are bushed for floating pins.

The machine shop that did the machine work on my 360 told me that he likes KB pistons because they are dimensionaly better and the weight more consistant than even high end pistons from the likes of JE, Ross, Probe, etc. He actually reduced the cost of the finish honing of my cylinders because he did not have to fit each piston to a bore.

At the current conversion rate 250 cnd is $217 US verse the Summit price of $188 US, not such a good deal. Before jumping you should consider getting the pistons as part of a complete engine kit. I purchased a kit from Mancini and had them upgrade the pistons to the KB107's and the upgrade price added to the stand alone price of the kit pistons was about $30 less than the stand alone price of the KB pistons.
 
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