Back in about 1962 or so, I had a 58 Corvette. Stock 283 cube 245 HP motor. I used new Chev 327 fuelly outer valve springs, 348 350 HP inner valve springs, new chev solid lifters on a Clay Smith 284 degree cam set straight up. Stock ignition and exhaust. I shifted it at seven grand by the stack tach. Years later, when visiting with a fellow who raced a Corvette, he said my figures didnt come out right when I told him how fast I went in each gear. I knew the tire size, and I knew I had a 4:11. He did some math, and told me because of the cable operated tach off the back of the generator, because of belt slip, I was actually shifting at 8,000 or just a tad over. It did sound really good doing it too! And it lasted for years.
One of my favorite movies is, "Frankenstein". I thinks it's because of the Mad Doctor Frankenstein. He's a guy, trying to make something that's crazy powerful, with just a bit of knowledge to go on. Love it!
I'd be concerned about the cast caps for sure @ 8000rpm. Unless you are using a stud girdle and some really good valve springs and valve train components, that's where the problems will begin. What cam are you using with cast heads that will make any power up there anyway? Don't see the need to try for that rpm?
Sounds like my first engine when I was 17, and many others as we learned . Back to the O.P. , for what you want to do , be sure to have a good scattershield or blanket. As for a Three or four run engine, seriously, I'd get a runner, put a good cam, lifters, and maybe springs, and run it. more points for used parts. Yes, I have done it, yes it was fun, yes I destroyed things, Ironically, it was a 327 out of a 3/4 ton truck, and in the end, the block cracked
It's not so much how many RPM you're turning, it's load that is trying to blow the crank out of the block.
Thanks everyone, lots of constructive comments. Additional plans and thoughts are.. Head are a set of 69 or 79 lt1 heads fully ported by Joe Mondello and are art work. Planning on some Yella terra shaft rockers, considering beehive springs if suitable but accept the valve train is the week spot if gotten wrong. Induction is undecided as is final cam specs, but will be a non roller solid lifter but as I said I've got modest goals. RPM limit is 8,000 to allow for missed shifts etc or a banzai run but just building to be able. If the heads don't flow enough to support it then the revs will be limited. As to why, well it's a fun car for a couple of times a year and I've always wanted to build a mad motor and I've got a doug nash 5 speed so why not. Will run some compression, 11+ with race gas and 0.040" ish quench, care for the oil control naturally. Has certainly helped my focus on the squaring of the block and a good balance so the short block is tight and together, and if done right will survive.
I ran D/GAS in 1964 with a two bolt 301 built on a 283 block. The machining was done by the best engine builders in New England and balanced as close as parts would allow. I ran it to 8K most of the time and tore it down several times during the season to freshen the rings and bearings. The thing you need to watch is valve springs. By the best stuff you can get and keep it light weight. Titainiun retainers and keepers are cheaper than destroying the engine. Roller cams and stud girdles are your friends. Why are you running the long rods by the way?
Running long rods to allow for lighter pistons as you use pistons design for a 350 with 6" rods and reduce the CH. Also many more choices.
I freaking love Talking with Lamar. It's for real. He did it and he didn't ask anyone if he could. He just did it after he thought about it for a while. He was smart so he was good at it.
I was wondering about the long rods. Cant remember if that was good for high RPMs but the stroke / rod length has a hole lot of other factors. As stated the 2 bolt main wont be the problem. If the top end is not correct it wont make it that high anyway.
And more importantly, he doesn't give a fuck whether you believe him or not--meaning, he has no reason in the world to lie or impress anyone. Having been in shops as a magazine guy for 15 years, my bullshit meter is calibrated pretty well. Lamar is the real deal, and I knew it five minutes after meeting him. When he helped me with my stroked 283, I asked him what cam specs I needed to make 400hp with a max 7,000rpm redline, on pump gas. He asked me the bore, the heads, the compression, leaned back on his stool with his hands folded and resting on his belly, stared off into the distance for a couple seconds and said "Write this down: ..." 403hp at 6,000rpm was what the dyno said when the engine was done. I asked him about 4-bolt caps for small-jourmals, and he said they aren't needed; the caps are the same whether they're large or small journal: the difference is GM hogged them out more for the large journal, which took material away, which makes them a little weaker. The factory fix was 4-bolt caps for HP applications, but the 2bbl small-journal caps are already beefy enough. -Brad
2 bolt mains aren't a problem ran 331's in two cars one car had 5.67 gears went through the lights at 8000 rpm on every two days a week from may to oct. ran a good pan and oil had to re-ring a couple time a season checked or changed all springs if a coil broke one spring ti-retainers 10*locks bbc size rocker studs(to-day I would use ARP) roller rockers
The longer rods are in your favour. Light pistons help a lot too. The force generated are a combination of the mass you are decelerating and accelerating, and the rate of said acceleration. The lower L/R ratio reduces the peak piston acceleration, and the mass you are yanking on is less, both will go a long ways towards reducing the violence on the webs, caps and crank. As Afaulk says, the power level is more of a concern than RPM when you are looking at the forces that will cause cap walk.
Probably cant add much than whats been said, aside from my latest sj 327 i built for my 32. Its a 6" rod with forged 383 slugs to drop comp for a blower. H beam rods, 7/16ths rod bolts and main studs. Id have NOOO problem what so ever pulling 8k out of this thing. It may not make power up there, but it'd probably live til the boost became too much. Lol But, i also did up the valve train in similar fashion. My point, just make sure you cover all the bases, top and bottom. And truly cant stress enough about have a quality machinist do the work. There's some good info in this thread. It all works together. Tony
I turned a 302 in my stock car 8.5 once sucked all the rings off the pistons all junk after that run stock SBC 7500 and moded ones in stock cars and they live forever
The same forces acting on the piston pins are acting on the rings. As the mass of the ring is reduced, it will become more stable in the land at high rpm.
personally, Id throw it on a dyno and find the curve, Then keep it in it.... My weed wacker can spin 10K, think id power my car with it??
The weight difference between the pistons is minimal. A 6" rod will stay at TDC & BDC (dwell) a bit longer, helping take advantage of your iron heads. A 6" rod will reduce some side loading on the cylinders, but you have a shorter piston that is prone to "rock" a bit in the bore. If you are looking for an engine that will last for many years and miles, a 6" rod is probably not a good choice. On your build, a 6" rod will be worth less than 15 hp. If it were a max effort build, then yes, a 6" or longer rod would be optimal. If you are going by Smokey, he was a fan of long rods, to make up for the poor flow of the old heads. Plus he built RACE engines, that were used and rebuilt/replaced often. Reher Morrison used to have articles about long rods on their site, not sure if its there still? Isky cams also has/had articles on their site. Do some more research of the pros and cons before making up your mind. Also, the magazines have been preaching long rods for years, why? That's how they make money, advertising products for company's and sponsors. If you get a product for free, you better write about it.
Reher Morrison changed their site since I was there last. Go to the tech tips, the rod length debate is there somewhere, I just didn't feel like going thru all the articles. Here is Isky tech articles, scroll down to the rod length post. http://www.iskycams.com/techtips.php#2005
Once again lots of good comments and I feel comfortable to continue with my plans without splayed caps, especially after Brads comments so thank you mate. Re the rods, I'm using the 6.125" rods so I can buy off the shelf pistons designed for a 350 and a 6" rod which reduces the piston CH 1.675" to 1.250". I needed new rods and a great deal on the H beam 6.125" SJ rods came up so decision was made. Ideally a 6.250" rod would have been used but not many SJ configurations out there. For me it's the overall approach, I have a good block and crank and a beautiful set of Mondello Porting Services fully ported heads that deserve some attention and to be used in anger again. The rods allow a better choice of pistons with metric rings which for some are unnecessary but to me sums up the why leave something on the table approach if you know about it. Except a roller cam due to the cost enough though it would make a dramatic difference. It's a mechanical exercise that I have studied for a lot of my life and will be fun car drive and to watch, there's not enough high revving small blocks any more. Yes a big inch what ever will out perform etc but hey, it'll be fun. Thanks for everyone's comments, its been an interesting and very helpful.
I have your dream 327 in my 67 Nova 327 + .040 (small journal) Filled Block 6.125 H beam Rods Wiseco 14.1 Pistons 210cc AFR comp ported cylinder heads AFR "Titan" composite intake manifold 900 cfm Holley Carb (methanol) Comp cams solid roller 2" step headers All this in a 67 Chevy Nova, 1/4 mile times (9.30 et at 147 mph) makes 625HP at 8500 rpm PM me for more details Desert
ARP stud kit on original main caps, Just for reference this short block machine work was professionally done my engine guy in Delaware. His shop is called "Awesome Engines" Stock block was bored, plate honed , filled to water pump holes with block filler to strengthen the cylinder walls. Crank align bored , Balanced with the aluminum flywheel , ATI balancer was added after assembly. Pistons are zero decked to achieve maximum compression. I know this is a lot of work on an OLD 2 bolt small journal block, but I wanted to tell anyone where I race its just an old 327 block...LOL My idea came from an old article in "Chevy High Performance" magazine about a 550 hp 327. Tony Mamo of AFR was quoted in the article by saying if I knew it would make this much HP I would have done somethings differently. His changes included: *Longer connecting rods (6.25 with Honda journals) *Larger heads (195cc-to 210cc) *Larger intake manifold (His AFR Titan Composite) *Larger lift solid roller camshaft *Extra rpm , 8000 plus http://www.chevyhiperformance.com/t...k/0811chp_327_small_block_chevy_engine_build/ I contacted him about his comment , this led him working with me on this engine. He also had his own camshaft grind made for me from "Comp Cams" I had another gift from Tony at AFR , I received one of ten prototype composite intake manifolds that came port matched to my 210cc heads from AFR. He was shocked this combo made over 600 hp, I'm not sure how safe the combo is for longevity. But I run an engine diaper that with stand anything catastrophic from leaving the motor area. Desert
The magazines fail the mention the CONSIDERABLE decrease in peak piston acceleration due to the longer rod, and the improved rod angularity, both of which reduce the forces transmitted through to the caps and main webs, which is the entire point of this this thread. And yes, Comp Cams spend more on ad money than anyone out there, and therefore, get more ink. I'm gonna sign off of this, before it gets too thick.
I'm sorry this thread has strayed off track. Please let me end my post by saying I would not be afraid of any combination of parts you can assemble for a "Street Engine" my situation shows what these little motors are capable of. Is there better stuff out there? Hell yes. The whole 2 bolt vs 4 bolt IMO doesn't matter on a street engine. (I'm talking about NO Nitrous or Turbo boost) It all depends on you stroke combination. Desert
Great info Desert, your engine must sound pretty mad with the compression and rpm, bet its a track favourite! Thanks for sharing your thoughts and details, with attention to the detail, the parts and the approach most things can be acheived, maybe not for 100k miles but that's not the goal anyways. Had been considering a 1/2 fill as well, what's you view on main cap girdles, any benefit in a N/A engine? In my head the fill, good machining and the studs would result in a happy place without detonation.
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