aftermarket cams?

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rebeltaz83

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just a thought rolling around in my head, but i was wondering if anybody knows if aftermarket cams are available for the vmax gen 1. shorter lift with a longer duration, so i can possibly get 12,000 rpms or more out of the engine, the 9,000 just doesn't seem like enough. seems i could get 11,000 out of my 78 goldwing at wot. I was also wondering if you could change the duration and the lift by using shims? i'd like to get this to kinda cam like a big block when it idles, lol..... with an extremely high lift short duration cam shaft. just some easy top end upgrades for now.
 
Mega Cams might grind whatever you want but I think they have a Vmax can on hand.
 
You'd need valvesprings too, the bottom ends aren't really all that good to take that kind of rpm either especially stock. Focus on making more horsepower under 10,000 rpm and you'll go faster and it'll live longer.
 
Stock pistons won't clear. Also, stock rods will take a shit on you. The original vmax's (for many years) had a 9500 redline. The last few years (with even the best rods) were dropped to 9k even though the engine can rev much higher. You'd need to get a longer rod (which can easily be provided) and lighter pistons with deeper valve reliefs for the bigger cams. The shim under buckets, the heavy duty cams and more.

I can provide all of that but it's not very cheap at all.
 
We can get any profile made you'd want but again with stock pistons this is not worth the cost or effort required for the install. His goal of 12k rpm is not going to produce a very long lived engine either way.
 
We can get any profile made you'd want but again with stock pistons this is not worth the cost or effort required for the install. His goal of 12k rpm is not going to produce a very long lived engine either way.

was just a thought. i would prolly go with a shorter stroke if i went with a bigger cam. sounds like a major headache just for a few more Rs, i'll leave it as is for now. if something internal lets go, this engine (if salvageable) will get a major, major overhaul. but thats a big IF something lets go. i know with car engines a small block will turn faster than a big block due to the shorter stroke of the crank and the rods. kinda new to motorcycle engines.
 
Sean.
This is kind of a theory question.

Based on what you know about these engines.

If you destroked one of these motors to something around 1000cc's

Put the best rods and pistons money could buy, balanced with great care.

Did the best most thorough upgrades to the oiling system possible.

Assembled it with extreme care in regards to bearing clearances.

And good valve springs.

At that point what would be the weak point in the motor as far as spinning the hell out of it?

I'm still guessing rod bearing or oiling system?????

I think it would be a very interesting build if it would stay together.....not for any good reason other than "just because you can"
 
I would not even think of building a vmax for that sort of RPMs. Among other things, Thats not where the fun is on a max. The fun of a Max is torque. If you are serious about building the motor, You should call Sean and talk to him. He can build you an engine with mega torque for less then a motor to turn 12,000 rpms and on the street that big torque motor will be many times more fun. If you want to turn a lot of RPMs and sound like a bunch of bees in a can, sell your V-Max and get a B king. won't be as much fun, but as long as you want to tap dance on the gear shift it will be much faster
 
I would not even think of building a vmax for that sort of RPMs. Among other things, Thats not where the fun is on a max. The fun of a Max is torque. If you are serious about building the motor, You should call Sean and talk to him. He can build you an engine with mega torque for less then a motor to turn 12,000 rpms and on the street that big torque motor will be many times more fun. If you want to turn a lot of RPMs and sound like a bunch of bees in a can, sell your V-Max and get a B king. won't be as much fun, but as long as you want to tap dance on the gear shift it will be much faster





I've already got a stroked Vmax, 1540cc that makes mega torque and HP.



I am just intrigued by the idea of high revving, smaller displacement V4.



Aprilia and Ducati have done it at 165-175 HP and they're quite impressive.



They sound awesome too. Still sound like a nasty V4



I have destroked a SBC 350 to 327 (305 crank) and a 327 to 302 (283 crank) and they were no slouches either. Less torquey for sure, but screamers that pulled hard all the way to redline of 7000-7500
 
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The gear head in some of us makes cams a subject for thought, and why not? It worked wonders in our car engines. But, it seems like the bang for the buck is in displacement with our bikes, boring and stroking. I like stroking to keep the cylinder wall thickness. Just my H.O. but cams aren't cheap. And the mods needed to run high lift are pricey too. Stroking like you did Rusty, seems to be the way to go, for a street motor especially. A safe bump in compression and good tuning, and the fun begins.
Steve
 
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The gear head in some of us makes cams a subject for thought, and why not? It worked wonders in our car engines. But, it seems like the bang for the buck is in displacement with our bikes, boring and stroking. I like stroking to keep the cylinder wall thickness. Just my H.O. but cams aren't cheap. And the mods needed to run high lift are pricey too. Stroking like you did Rusty, seems to be the way to go, for a street motor especially. A safe bump in compression and good tuning, and the fun begins.
Steve

as i am slowly finding this out, lol...... but atleast i asked before i went and bought high lift cams just to find out they won't work the hard way, lol. cams are not cheap, for a cam set with a slight higher lift and longer duration it was over $800. definatly a build for when this engine needs a rebuilding some time from now, i hope. it's fast now, so i'm conetent..... once you open the up the bag for the mod monkey, and speed demon.... they don't go back in very easily, or not at all.
 
I destroked a SBC to 283ci and it was no slouch either. Less tourqey for sure, but a screamer that pulled hard all the way to redline.

NASCAR engines are basically destroked 400SBC motors, (4.185x3.25) and look at the hp they crank out. Granted, those cars run on race fuel, and do not have a whole lot of bottom end torque.

If I were to build a motor for a Vmax to produce a ton more power, I think I would set the limit at 10k rpm, and even then, I would want the bottom end built like a tank. The only reason I might want bigger cams would be if the displacement of the engine was up there in the 1400+ range or higher, which would then need more airflow through the heads.
 
Yea, you can do the shorter stroke, longer rods, light pistons, different profile cams, larger valve heads with port work, and get some more rpm's out of it. I don't think you'd really get much of a gain in over all power (when compared to a big bore) but the range would shift that it makes the power at.
 

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