To stroke or not to stroke......

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Vortex

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Hmmm....Big choice to make. I'm thinking of swapping my 318 for a 360 in my 68 barracuda. Well, I've been kicking around the internet and I haven't found the answer to my questions.
I want a STRONG street/strip engine. I use my Cuda only in the summer months as a dd. (garage in winter) And I race a couple of times a month.
I haven't read anything on building a hot 360 or going for a stroker. Which will give me more at the track? And will it be driveable on the street as well? What are the pros and cons? And have any of you built a stroker?
My buddy(an engine instructor at a near by univ) plan on building the engine over the winter so I want to get a head start. And my budget is high enough for pretty much anything.
Please, any imput would be great. And I don't want a crate motor. We want to do it ourselfs.
 
I built a 360 +.030 with the Mopar cast 4.00" crank. I think it was 408". That damn car was a runner. I just had the edelbrock RPM cam and air gap manifold. The heads were stock 360 heads w/ 1.88 1.60 valves. I did gasket match and clean up the area under the valve a little bit. The car ran 12.70's with a bad 3rd gear 904, 2400 and 3.23 one leggers. I barely got into 3rd at the track. With a loser converter, a solid roller cam, a shorter gear, and a good tranny, it would have been running low-mid 12's.

Also, I just ran a 600 VS holley. Probably could have used a 650 or 700 DP.
 
If you have the cash go with the stroker. The longer stroke will keep it tamer on the street.
 
Being your racing will be bracket racing horsepower is irrelevant. You mainly want a reliable package for your motor regardless of size. I have raced street cars as slow as 17's and race cars as fast as 10's and have had just as much fun running 17's as the 10's and really fun is the name of the game at least in my opinion. I have seen many 318 run very well but if your car needs and overhaul anyway and you already have the 360 you might as well go the 360. There is no clear cut answer to your question, it is mainly a matter of how much you want to spend or how fast you want to go. Again you don't need to be the fastest to do well in bracket racing.
 
Again you don't need to be the fastest to do well in bracket racing.
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Never truer words on the subject!
If I had your budget,
And my budget is high enough for pretty much anything.
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I would suggest to any freind of mine that the 4 inch stroker is the way to go for many reasons.
It's abilty to make crazy torque. More torque is, in other words, the abilty for you to say to the engine, jump, and it will without effort at the drop of a hat. (Or foot)
Bigger engines can take bigger cams for more power without getting the streetabilty in the garbage can.
The con is extra expense and time in parts selection, clearancing rods. Thats about it. Gas consumption???????? Do we care???????? LOL, NO!

Nothing wrong with the 360 in anyway shape and form. It's your choice on a 40+ cubic inch difference or not. Thats really it.
 
But we forgot piston side loading and crank stress on the main caps, and loss of ring seal, piston rock even with tight clearences, bad rod ratio and rod angle, bad bore to stroke ratio and stroke to rod ratio, hummmmmm did I miss anything maybe let's see where it go's from here, then I'll think of some more.
But when you can crank 400 - 500 HP out of a 360 for the same money that the parts will cost then it just doesn't seem feasiable to build a stroker.
But this is my opinion, and can be taken for what it's worth.
 
But you wont need to rev it to the moon, plus lighter rotating assembly will bolth add to longer life.
 
I have built both a 340 and a 4" stroker 340
I was very happy with the stroker motor feels like a big block.
I would never go back to a standard stroke in a street or drag car.

The down side is premature wear of the rear tires :toothy7:
 
My $.02...For a summer months car, side loading, and premature wear would not top my list of things to watch for. The typical car around here (CT) runs for 6 months, and gets between 3-6K a year as a daily driver during that time. If it makes it to 50K, that's 10 years of use. The "high milage" ones I've seen locally are still in the 30-35K mile range, but run just fine. And that's running them all year, from 100° (last week) to 0° in the winters. (ok, the forged pistons get noisey when she's really cold..lol.) It's cheaper and easier to build the 360. In an A body, that's some cruiser, some race car, mid-low 12s and easy repeatability on pump fuel is a cinch with 4.00:1 or lower series gears and an auto. But, for a cruiser, 4.10s can be noisey (engine wise), and will add wear and tear on that engine, just like any other. For about 15% more, a 408 can be built, that will run very low 12s, on pump fuel, but do it on 3.23s, with a tight convertor. In terms of budget, a "typical" 400-450 hp 360 will run $5000-5500. That's carb to pan, all new except head castings, rods, crank, timing cover, and block. A 408 will run around $6K, plus a few hundred more for aluminum heads if you chose them...and I would if it were me. Again, all my opinion...
 
One of the 360's that we have runs on pump 93 and runs in the mid to upper 11's, including all the machine work and parts the total bill is just at $3000.00 when we did it a year ago. The price now would be 25% higher as parts went up like everything else. The car scaled @ 3290 lbs. and never went over 6000 rpms I believe it went thru the traps @ 5700 rpm's or so.
The aftermarket parts were a comp cams cam, mopar intake, holley carb., comp springs, adjustable rocker arms (iron), a set of chrome moly pushrods 5/16, and comp lifters.
The rest of the engine was a rebuild kit with rings, brgs., gaskets, chain and gears, oil pump and screen, after this the rest was in machining $1600.00 worth. This engine now would cost about $3300.00 - $3400.00 due to parts cost. This would be a very streetable engine and run too and could easily go 100K mi.. Mine did after 3 years in the work truck at 35,000 mi. a year and now at the track.
Just my .02 worth.
 
BJR Racing said:
One of the 360's that we have runs on pump 93 and runs in the mid to upper 11's, including all the machine work and parts the total bill is just at $3000.00 when we did it a year ago. The price now would be 25% higher as parts went up like everything else. The car scaled @ 3290 lbs. and never went over 6000 rpms I believe it went thru the traps @ 5700 rpm's or so.
The aftermarket parts were a comp cams cam, mopar intake, holley carb., comp springs, adjustable rocker arms (iron), a set of chrome moly pushrods 5/16, and comp lifters.
The rest of the engine was a rebuild kit with rings, brgs., gaskets, chain and gears, oil pump and screen, after this the rest was in machining $1600.00 worth. This engine now would cost about $3300.00 - $3400.00 due to parts cost. This would be a very streetable engine and run too and could easily go 100K mi.. Mine did after 3 years in the work truck at 35,000 mi. a year and now at the track.
Just my .02 worth.
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List your combo, not just the name of some of the engine parts you used either, I mean a complete detailed breakdown of what you did exactly to the engine, trans, and what gear and tire combo.

As to cost, I am with the others on this, if you are doing a rebuild anyway, and your budget permits, build the stroker, you will not regret it as the cost will only be slightly more than a standard rebuild and you will get way more bang for your buck, and it will last longer than a stock 350 cheby or a 351 turd. As for BJ's concerns, I am sorry to disagree with you but it is considered to be ideal to be somewhere between .80 and 1.2 for a bore-to-stroke ratio in general, and as a stock 360 is at .89 and a stroked 360 with a 4 inch crank is going to be 1.0, I do believe that places it smack dead center of what is considered to be ideal. Do a little research and you will see that I am correct. If it's all out max horsepower your looking for, then running a short stroke at high rpms is what you want, but if you want something you can drive on the street and has so much torque it can lift the front wheels with 2.72 ring gears and still go out and tear up the track, a stroker is the only way to go.
 
The bore to stroke ratio is 1.126 on a stock 360 engine and the rod to stroke ratio is 1.710, which is better than the 4" stroke. I'm sorry that we have to agree to disagree but everyone has there own way of doing things and if you feel that your way is better then by all means do it your way. Once again I'm only voiceing my point of view, the originator of this thread asked for the pros and cons and why.
As for the list on the engine the short block used a stock crank .010/.010 ground, stock rods that were resized on the big end only as the pistons were pressed fit, the pistons were .030 cast dished 10.8 cc's, they used .030 hastings rings std. ductile iron, the brgs. were king performance rod and main and cam brgs., the block was square decked and slick finish honed with 420 then with 600 w/wiper. The chain and gears were a melling HP dual roller, with a melling HV pump this pretty much takes care of the short block less the cam and lifters.
As for the aftermarket stuff the cam and lifters were comp cams .507/.510 240/246 @ .050 XE 284H, the carb is a 3310 750 with the secondary metering block kit and spring kit for the diaphram, the check ball was removed and the idle and power bleeds were enlarged .008 then jetted for air conditions and elevation. The intake is a M-1 mopar w/2" spacer, the rockers were crane's iron and crane 5/16 pushrods, the springs were comp cams 995's.
The heads were gasket matched and bowl blended with stock valves and a comp. valve job (narrow 3 angle) the valves were lightly back cut to remove most of the lip on the back of the valves but not all. The heads were cut to minimum as not to increase the comp too much as pump gas is the goal, the gaskets are .050 thick on the heads to block. The valve springs were set at 1.680 installed height at 130 lbs. seat pressure, but springs will vary so the installed will vary also due to spring tension, but this is where these were set at. The dist. is factory mopar and a chrome box, and timing is set at 35 total. The rear end has 4.10 gears and 28" tires, the converter is a 8" 4200 but will only stall 2800-3000 on the brakes before sliding the front tires. The transmission is a street and strip setup with a auto/manual shift valve body. The hedders are dyno max 1 5/8" street tubes with the race dyno max mufflers.
The engine was balanced to the gram on all parts, the ring gap's were .018/.024/.050, the brgs. were set at .003 rods and mains, this was the need for the HV pump. This is all that we did the car ran 11.784 @ 113.46 mph.
I hope this appeases the critics that are/were skeptical, but as always the machining will be different from one shop to another so your results will vary.
Sorry I PO'ed you krabysniper, but the engineers are alot more knowledgeable than you or I and I'm not trying to reengineer the wheel, just make it better by machining it better than production specs..
 
Well said. If I had my stroker to do over again - I wouldn't. The outline above by BRJ of a cost conscientious simplistic 360 build is the way I would go - maybe a few 10ths slower - but a lot more $$$ left in my pocket. :thumbup:
 
Actually with our cars and the way that we do them they are faster than the 408's, and 416's around here. We get accused of haveing bigger engines but the truth is we don't. We just have our S**t together, keep in mind I've been racing longer than some on here have been alive 30+ years so this isn't new, it's just very well refined. Also haveing 5 engineers for friends isn't bad either but is well earned. A trust that WON'T be betrayed, so I have 3 at Mopar and 2 at Ford the way I look at it is that I EARNED IT!
I'm here to help and not compete, I compete on the track most weekends, this also helps where I get my info from, I do it and test it, I also machine it and assemble it so QC is the highest and to (in my opinion) the highest standards. I'm sure that there are better than myself out there but with the help that I have it will take alot of $$$$ and training to get the same knowledge. Sorry for sounding arrogant but this is the way that it is.
If some don't like my opinions, than in your opinion you think that I'm stupid, then go about your way just as I will mine, don't take my advise I really don't care. I'm here to inform and discuss different things to the best of my knowledge and give the best answers to my ability.
If you want a stroker, then build one, if you want the same power out of a factory CI engine then ask, I don't turn my engine's any harder than the strokers and run as fast. Sorry but this is my opinion and take it for what it's worth.
 
BJR, Theres no doudt in my mind that you can build a killer motor on the cheap. You do what you do well. :thumbup:

Have you built many strokers though ? Im just thinking if you can build all that power with a 360 you could easily go 10s with a streetable stroker.
 
Adam,
Actually the torque is the only difference in a stroker and it will be more only if done properly, and the answer is yes I have done strokers and some very fast ones at that. But for the $$$ spent they could have went just as fast for less. But I don't spend others $$$$ needlessly, I show them what they want and then show them the drawbacks.
For instance a fellow builder spent $13,000.00+ $$$$ for a competitor and a stroker and I was .10 behind and saved $10,000.00, the fellow racer then listened to me and did a engine for $2,600.00 and ran just as fast. His comment to me was I should have listened 3 years ago. He was running low 11's with a chevy.
 
If I had the budget for almost anything for a smallblock build, here's what I would do. Contact Hughes Engines for one of their 4.18" forged stroker rotating assemblies. Then I would get Mopar Performance on the line for an R3 siamesed bore, 9.6" deck block. While you're there, throw in a pair of aluminum W9 heads with the 2.15" intake valves. Finish bore the block to 4.20", assemble with the intake, exhaust, cam, and ignition of your choice, and let the 468" worry about the power. You would still have .020 for cylinder wall cleanup if necessary and the engine would still be oversquare, which improves the bore/stroke ratio. Just my $.02. :thumbup:
 
I am sorry you took offense BJR, was not the intent, and I most certainly was not "po'd" . As you said, we can disagree, one of the things that does make the US a great country indeed. I just dislike when someone comes on and says " I put joe blow racing cam, super john racing pistons in and ran a million miles an hour on crap gas" (being facetious intentionaly) because truthfully, I find it hard to believe and it really serves nobody well, when the idea of a bbs like this is to share info and ideas, which is what you say you want to do. That is why I asked about your combo. If you did it, beutiful, but don't get all offended if someone wants details. Maybe someone else out here in never never land would like to duplicate it. They say imitation is the greatest form of flatery. Also I was not "attempting to compete" on the contrary again, I was merly asking about how you did what you claim to have done. I can say I climbed Mt. Everest or dove to the bottom of the ocean or flew to the moon, if I can't back it up with details it's all just so much BS. And :wack:

Having engineering friends is just great, I have many myself (several who are so smart they cant tie their own shoes. No, really, I am serious). :munky2:

I wont even get into an engineering disscusion as I just dont type fast enough to bother, the info is out there to be had by anyone who is dilagent enough to search for it. I do have to apoligize for my inacurate bore-to-stroke ratio, I took it straight from, you guessed it, an engineers book regarding performance building of the small block mopars, and as it turns out, he either had a brain fart, typo'd, or as I said about my own engineering friends, is so damned smart that he actually forgot the proper math of bore/stroke=ratio. Gosh, I guess them engineers can make mistakes too, eh? (I probably should have double checked it before posting it, but it was late (yes, I said late, I had already been awake for 20 hours at that point so I never realized it was wrong) and I was tired. **** happens. Which by the way, after rechecking the math, makes the true b/s ratio to be 1.117.. and a r/s ratio of 1.71 with a stock rod of 6.123, stock bore of 4.0 and stock stroke of 3.58. A stroker with a 4.0 crank and bore and same stock rods would be at a ratio of 1.1 and would have a r/s ratio of 1.53, which if you want to bring those engineers back into play, means squat actually. I will qoute an engineer that I am certain you know of at least even if you havn't met him and talked to him in person, his name Larry Shepard, the qoute "There is NO IDEAL rod ratio. The lower the rod ratio, the more torque the engine will make." So to say that rod ratio is "bad" in a stroker engine is wrong statement. Key thing to consider in rod ratio is placement of the little end of the rod in the piston, as a longer rod requires the pin to be moved higher up in the piston limiting and/or limited by oil control ring placement. But by moving to a longer rod to improve rod ratio you would reduce piston weight (usually a good thing) and would reduce the side loading of piston and cylinder walls you are so concerned with but would increase issues with piston rock. As I said, I believe a properly thought out and executed stroker can be done for just a little more (a relitive term actually) tha a stock build, and will perform better in a dual purpose machine. But as you said, we can agree to disagree.

On a final note though, I am seriously taken aback by your "I am greater than thou" attitude (smells alot like other holier than thous from another A body forum that I will leave namless as I am just as offended by some of their memebers attitudes and I will not leed anybody to a forum full of people who are so full of themselves they are blinded to reality), really unbecoming of someone who claims to have been racing longer than I have been alive, which you have not. I have been alive a much longer than 30 years. I am sure you do build fairly decent engines, and probably do well, but a holyier than thow attitude sure as heck wont get anybody to believe what you have to say, and may well drive some to seek info/advice else where, and would certainly not lead me or others to want to suggest your advice or services to anybody. Being so old and wise you should have learned that by now. :thumbup: Seems to be a character flaw with guys in your age bracket though, I guess. My old man seems to have that attitude about some things now and again and it tickles me to no end when he runs off on how brilliant and smart he is about something and I or someone younger than I succesfully demonstrate him to be wrong, tends to shut him up quick. Don't get me wrong, he is (and you may well be, I know I am) very intelligent, but, he is human and can be wrong sometimes (as can you, and so can I) so don't be so full of yourself that you insult others who may know alot more than you give them credit for. Please continue to share your wealth of info, but do it in a more apropriate, to your age, way and realize that not everybodies an idiot just because your old.

Glad to see we can debate the subject though as it sure drags the info out for others to chew on. :angel9:
 
Hey if everyone built motors the same way they would all be stock. What fun would that be ?

Anyway you look at it the extra stroke is going to add torque and/or lower the rpm range of the motor making it more fun on the street.

In my case the 4" crank would be the perfect way to make my motor more streetable. With a 7000rpm peak, 1200rpm idle and only 406ftlbs of torque at 5300rpms its not currantly the tamest thing.
 
Interesting read... As my wife would say " Anyway..."

I think (again, only opinion, but one BJR and I share from his posts) that the majority of enthusiasts know a lot about their car. They know a lot about a lot of things. But, when the science of a certain assembly in that car needs to be addressed, they may not know as much. The "jack of all trades, master of none" deal. Some know more than others. Some know the theory (the math). Some know the hands-on (the experience). That's why it's so important to have open dialogue such as here. One thing some better machinists know (and I am not a machinist by trade) is that the operator AND the equipment make the job. If one of them is off for any reason, the minimum result is lost power. It can get worse from there. Breakage, loss of $$, even injury depending on the incedent. (ever seen a "good" fueler crank making "only 870hp" as opposed to thousands come apart at 6K in 3rd? An exiting rod took the RF tire off the rim at 100+mph) The math never lies, if the inputs are correct. To accelerate 2800lbs to 114mph in the 1/4, one must make about 330hp to the tires thru the whole run. Those calculators assume that the rest of the system is optimized for 0-60+ acceleration. No tire spin, very limited torque convertor slippage, no trans slippage. The part BJR lists, and the small to medium cam he lists, can easily make that number (420ish at the crank) when the ring seal is right (the plateau honing), the balance is good, the valve job is good (the single biggest spot for power loss in my experience). I have an aquaintence who just spent $10K+ on a 500" race motor from a "reputable" local mopar guy. It's the 3rd one for him in 3 years. In a full race (2600lbs with driver) A body, it has managed a best of 10.30. It's barely making 1hp per cu inch. It just broke again. From what I've heard, the owner's remark was "For 10Gs, why do I have to adjust the valves?". I know of a 383 that's had more $$ tossed into it than I've spent on all the customers' stuff I've done in the past 3 years combined. That fellow hasnt smiled about that car in 3 years. But he still spends to get faster (mid to high 12s now). The last set of heads I did to replace exisitng ported ones due to a crack that developed, picked up .2 on a 11.60s 440 B body. It cost him 2/3s of what the first set cost 3 years earlier, and $300 less than a set of Edelbrocks. Most people dont have the experience to knowledge to know how good "done right" can be. So they rely on the $$ spent for the indicator. I've always used results to point me in the right direction. When I won a race over a bigger $$ setup, that was just the proof. When I watched my buddy's stock Cleveland Ford run 11teens, I knew who to ask and listen to for my questions. It's a long sales pitch really, but a good book to pick up is "How to Tune Demon Carburetors". It's loaded with basic info on engine theory, tuning, and physics. In addition to putting down "the industry" and elevating BG systems ;) .

"To Each, His Own"
 
Moper,
No better words that I could think of but you said "To Each, His Own" I agree.


krabysniper,
I guess you take my knowledge and abilities, and talants as a "I'm greater than thou" attitude, sorry you feel this way this definetly was'nt the way I intended it to come out. But since your younger than I and your more intelligent than myself, I look forward to your knowledge on how to machine and build engines, and I hope you can show proof of your work and detailed specs ( which I have never seen you post). I have delt with alot of people with your mind set. The way that I look at it is I've done it and I'm talking from experience no BS. So from now on I have nothing to prove to you or anyone else. If you don't like my thoughts then this is your choice, but don't belittle me from your lack of understanding. I look forward to your solutions for cam, head, and carb options, modifications, and results, and a explaination of why you choose these parts, along with other relative info.
Sorry that I have the confidence and the abilities to do so, and sometimes it comes across as arrogant or better than thou. But it's not intended to come across this way it's to be informative. But as Moper said " To Each, His Own" you have your way and I have mine.
 
BJR Racing it sounds like you know what your doing. but it would be awesome for the site if you posted some really good combos. it could help out alot of us here.
 
Working along the same lines, I will be rebuilding the 340 for my dart this winter. Now this all hinges on if the block will take another overbore as it is already .030" over. My plans are as follows.

another .02-.03 overbore (if possible)
360 crank turned down
aiming for 10-10.5:1 compression
eddy mag heads (will be mildly ported)
mag air gap
I'm thinking the xe 274 comp cams
700-750 cfm carb (no prefence on make)

I figure the turned down 360 crank is a cheaper way to gain some cubes.
The reason I'm going with the magnum heads is I plan to fuel inject the engine in the future and already own a M1 fuelie intake for mag engines that is on my 97 dak at the moment.

Now by my calcs, I figure I should have a very solid 400 hp possibly more.
I still not sure on the cam and would like some suggestions for this.

Thanks
 
Do you mean turning down a 360 crank to a 340 main size? If you do I believe this really weakens the crank badly.
 
dartfever,
IM me with the year of the block, cc of the heads, length of the rod's, what type of rockers, and pushrods, what cfm TB you intend to use when FI, what Injector nozzel size, the rpm's you want to turn, port volume of the heads, as they rarely are the size they are advertised at, and valve size. Then I can give you what you need to get the job done.
 
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