350-400hp budget build 360 ideas???

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dusterdan

dusterdan

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i recently purchased a 71' 360 with 727 trans that's never been apart and only had 60,000 original miles. this is the factory 2-bbl engine rated at 255hp as is. this motor has the 1.88 J heads. what are some economical ways to get about 350hp-400hp from this setup? i was thinking 2.02 valves, higher compression pistons, cam etc... i'd like to spend under $2,000. i have acquired an edelbrock performer rpm air-gap intake manifold and i also have a 600cfm thermoquad. this is going in a street driven duster with 3.91 gears. i'm 20 years onld and this is my first engine build so any and all advice is greatly appreciated! thanks again everybody!!!
 
flat top pistons, better cam, 2.02/1.60 valves and a 750(or so) carb. That or you could stroke the thing and easily get that power and more.
 
XE274 hyd
750 vac sec
Find a way to get your stock pistons and head to net you 9 to 1 compression
Edelbrock Air Gap
3/4" headers
 
Important lessons to learn early. Compression is key. Know what yours is with any given combination of parts.

Chances are your pistons are significantly down in the hole, so you'll have to use a pretty small chamber and a thin gasket to get it tolerable.

RHS LA-X heads (they've got the big valves, flow better than any stock head, and have a smaller combustion chamber to aid compression.
Skinny head gaskets (318 gaskets are .035, Mr gasket and Mopar make a skinnier one)
Air Gap
750 Holley

Camshaft is hard to quote, because there are a lot of unknowns with his motor. I would keep the duration down to a reasonable level to salvage dynamic (rather than static) compression.

Good oil pan is cheap horsepower. I like my Kevco.

Headers are obviously going to be needed to make that horsepower.

Avoid a high pressure oil pump, they cost hp to run.

Take your time.

Steve
 
Get a set of EQ Magnums with the LA intake pattern. Bolt them on and stick in a cam like the XE268. Run a set of cheap headers and what you have. If it doesnt make 350hp it will be very close.
 
you guys have already been tremendously helpful! perhaps i'd like to mention this car will be running power brakes. is it worth it to buy the LA-X RHS heads or have 2.02 valves put in mine along with all the necessary work? i'm not too familiar with the price difference between the two options.... i'd love to have the eddy rpm's but not exactly in the "college budget" at this point in time unfortunately
 
For as much as you'll be in a set of factory iron heads putting 2.02's in them, suck it up and buy a better head.

350hp deal

360
9.5:1
J heads
LD340
750DP
Comp XE268H
1 5/8 headers

Be right at 350hp and 400tq
 
heres a awesome link to dyno proven 360 builds hopefully i can do build nine someday for my duster and like mentioned in this article with a little more tweaking to the engine and upgrading parts you can easily sqeeze more horses out of the engine good luck

http://www.mopar1.us/dyno.html
 
The first problem is "Collage Budget" and the listed $2000 dollors to spend on this. Your not going to rebuild this for that amount. To get to the tagert amount of power with the money at hand, I suggest the following;

Shop the classifieds/Craigs list for used and inexpansive parts.

To use the TQ carb;
An Edelbrock LD340 and have the carb pad modified to work with the TQ. Add a 1/2 spacer under the carb. The TQ comes in 2 sizes, 800 & 850. Measure your primary throttle plates. If the 1.50 inchs each, you have the 850.

To use the RPM air gap, add a 750 cfm carb.

Cam, IMO a 340 cam will do it. Purchase this brand new along with the matched springs for the cam.

As Moper said, cheap headers into 2-1/2 inch exhaust

The heads are where the big expense comes in. Mill the heads a little bit and have them bowl ported. (AKA Pocket ported) with a bracket valve job. Add 2.02 intake valves if the wallet allows it.
 
Yeah, that budget for me is very limited. That's why I said EQ Magnums. They'll support that power level and can be gotten for $600/pr or so. The rockers are stock Magnum, any boneyard or probably members here have a spare set. You'll need oil-thru pushrods and a lifter that has the oil feed in the top. Most mopar stuff do now anyway but technically they are for AMCs. I think by tring to rebuild the short, or the heads, you'll wade thru that $2K before you get a running engine out of it. I figured $700 for fresh heads and the rockers, the rest can go into headers, exhaust, gaskets, paint, belts, hoses, etc etc etc...
 
yeah i plan on saving up as much as i can i'm about $1500 already but that's not far enough unfortunately duster731, that link was awesome!!!! of all the packages, number 8 seems like a hot ticket as it still has street friendly compression! got me thinking about some "plans" haha thanks again ya'll!
 
I agree with Moper, rebuild is going to eat your whole budget before the hot-rodding starts.

If your short block is running, throw a good set of heads on there and you'll be miles ahead.
 
When I converted my duster from a slant six to a 318 purchasing all new parts and machine work I think at the end my tab was about 4000$ but I started from scratch and all new parts.... what would save you a lot of money is doing the work yourself
 
350-400 HP is well within the reach of a 1.88 intake valve. Some of yall need to look up the definition of the word "budget". Jus sayin. Far as I'm concerned, crackedback is right on the money.
 
StrokerScamp said:
350-400 HP is well within the reach of a 1.88 intake valve. Some of yall need to look up the definition of the word "budget". Jus sayin. Far as I'm concerned, crackedback is right on the money.
Click to expand...

I agree the 1.88's rebuilt with some minor work will give you the HP and save you money.

My 360 combo is a 9:1 PAW short block with reworked 1.88 J-heads. 280H Comp Cam with Weiand Stealth manifold, 750 Eddy carb and Hooker headers. Runs great, pulls hard and lays rubber at will.
 
MY340, what exactly are you referring to when you say "reworked" heads...as in a good valve job or something? as far as compression, how far up could i go to still run on 91 octane...perhaps 9.5 or 10:1?
 
StrokerScamp said:
350-400 HP is well within the reach of a 1.88 intake valve. Some of yall need to look up the definition of the word "budget". Jus sayin. Far as I'm concerned, crackedback is right on the money.
Click to expand...


That was never in question. Cost is the determining factor for me. Good headwork (I'm talking about all the labor, parts, etc) costs too much on a $2000 budget.
 
No doubt. That would be the first or last thing to do. Because of expense. Considering that if your starting with old greasy heads, the price in total could very well be $2,000 from start to finish. I don't care who or what site price list you point to. By the time you take off the head and get it back on the engine, it'll add up real fast.

Cost of shipping to and fro, cleaning up the head from degreasing to machine work on the deck side, (Clean up cut) gaskets, new valves and relateed hardware up top matching the new cam. All I hear is ka-ching - ka-ching - ka-ching....

All left over monies go to cam, intake, and headers into simple straiught tubeing and mufflers and cheapies at that to stay under budget. If even possible.
 
dusterdan said:
MY340, what exactly are you referring to when you say "reworked" heads...as in a good valve job or something? as far as compression, how far up could i go to still run on 91 octane...perhaps 9.5 or 10:1?
Click to expand...

Offten "Re-worked heads" refur to a rebuilding of the heads with minor performance mods done to it. Things like a milled deck for compresion, trick valve job and/or new valves along with it is the basic idea.

While basicly a stock rebuild, the added "Tricks" allow for nice gain in performance with still what is basicly considered a stock head. No porting done at all.

IF 91 octane is your best gas at the pump, I would stay at 9.5-1 as a absoulte max. If your running a small cam, back it down a 1/2 point of compresion.
 
Hey dan.. If you do decide to go with a comp xe268 cam i have one over on the classifieds.
 
hey appreciate the offer i checked out your posting....upon trying to decide "where-to-go" with this motor i think i'll end up being in the hole ALOT more than anticipated but i want to do it once and do it right ya know so i'm really looking bigger hp numbers. i like your 416 stoker that is badass!
 
dusterdan said:
i recently purchased a 71' 360 with 727 trans that's never been apart and only had 60,000 original miles. this is the factory 2-bbl engine rated at 255hp as is. this motor has the 1.88 J heads. what are some economical ways to get about 350hp-400hp from this setup? i was thinking 2.02 valves, higher compression pistons, cam etc... i'd like to spend under $2,000. i have acquired an edelbrock performer rpm air-gap intake manifold and i also have a 600cfm thermoquad. this is going in a street driven duster with 3.91 gears. i'm 20 years onld and this is my first engine build so any and all advice is greatly appreciated! thanks again everybody!!!
Click to expand...

I'd get some Keith Black HyperEutectics they'll get your pistons higher in the bore and increase compression quite a bit. Funny the 360 KBs are cheaper than the 318 KBs. I think it has something to do with a larger bore and a longer stroke makes for a shorter piston overall. There's a website called 'enginekits.com' that will sell you a complete kit to rebuild the bottom end of your motor and allow you to swap in the Hypers for a small price. Much cheaper than buying the set by itself. Quite a deal, go for the Master Kit. You get mains, rod bearing, gasket set etc., everything you need. I think your going to need an adapter plate to bolt that TQ onto an airgap intake. TQs are 'spreadbore' the secondaries are larger than the primaries and the Airgap is made for a 'squarebore' where all throttle plates are the same size. The TQ needs extra room for the secondaries to open otherwise they will hit. Look at different intakes on Summit you'll notice some will have a larger opening on one side to accommodate for spreadbore carbs. I have a 800 cfm TQ for my 318 I am building, they are nice because even though they are overrated for the motor the use of a 'air valve secondary' allows the engine to only use what it needs for flow. It takes a little adjusting to get it right by setting the spring tension while the engine is running but they are worth it.
 
I give Ricks post 4 stars.

(I also think that the reason behind the cheaper 360 piston vs. the 318 piston is customer demand. I beileve machining the 318 slug is a short step, but one that takes them out of there normal route of machining a 4 inch plus slug so often seen and used by the big 3. And like you said, the extra aluminum in the slug itself.)
 
Rick thank you very much for the detailed info i'm definitely looking into that website it looks like they are very affordable i'm narrowed it down that i'm gonna take my block to the machine shop and have them hot tank it and then see if they have to bore it at all from there, i'd like to clean everything up like the crank, rods, heads etc and then start purchasing a set of pistons. how much would you guys say the basic hot tanks runs?
 
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