Pred 670 RPM to MPH?

[slonomo]

I'm also going with a 23" tire. I do like low end torque and I'm not trying to go fast anymore, just smooth cruising and lots of acceleration. Post some pics!

[dpalacio1]

Here some pics!

[slonomo]

Nice cart!

[dpalacio1]

Thanks Slonomo! I did just order a header pipe for this too instead of this one that came with my kit. Geoff at VC took care of me as it is custom order. I guess they don't make it any more but will on request.

[kgsc]

Nice ride. Helped you out with the pics.

[dpalacio1]

Thanks for the assist on the pics, wasn't sure why they were rotated, I took them off my phone??

[kgsc]

Not the expert but try rotating the phone on its side to take the pic.

[dpalacio1]

Originally Posted by slonomo

If people are reporting 35mph on stock gearing with 22" tires.....they are about to blow the engine up

Safe speed with your setup is 25mph. Stay at that speed. And yes that sounds about right. If you rev that engine up past 4500 rpm it will likely damage the engine. If you want that much rpm you need to build the engine to handle it. A good rev kit will get you to 5000 safely. The rev kit will eliminate the valve float.

Past 5000 you'll want billet rods with replaceable bearings, that will get you to 6000. Revving that high you'll surely want to get a new flywheel. My 2 cents.

Bigger tires will give you more mph for sure. Going up to 25" tire will give you 5-10 mph at the same rpm. I did this on my last cart. Didn't affect low end pull at all with the 670.

Swapping gears in the transaxle to 8:1 will also give you 5-10 mph at the same rpm.

If you do the rev kit and 8:1 gears....you'll like the results. I just hope you also get front brakes.

Question: So i do get 5 to 5200 occasionally I just don't keep it there long. This motor is stock. Would you advise getting heavier valve springs? I don't know that I want to go the extra for billet rods and flywheel for a golf cart that is used to cruise around the neighborhood. It runs fine and seems to be turn key on any given day. Oh, BTW I just got 23" tires installed and it rides nice with 15 lbs of tire pressure!

[slonomo]

Originally Posted by dpalacio1

Question: So i do get 5 to 5200 occasionally I just don't keep it there long. This motor is stock. Would you advise getting heavier valve springs? I don't know that I want to go the extra for billet rods and flywheel for a golf cart that is used to cruise around the neighborhood. It runs fine and seems to be turn key on any given day. Oh, BTW I just got 23" tires installed and it rides nice with 15 lbs of tire pressure!

The stock valvetrain is not up to the task of 5000+ rpm. I've heard of bent pushrods above 4000 rpm. I'd get the heavy valve springs, not the dual racing springs, and get the steel pushrods. A cam isn't hard to change, I'd probably get a cam too, but that's just me. Watch rpm above 5000 it'll wear the connecting rods and eventually you'll be knocking.

[dpalacio1]

Originally Posted by slonomo

The stock valvetrain is not up to the task of 5000+ rpm. I've heard of bent pushrods above 4000 rpm. I'd get the heavy valve springs, not the dual racing springs, and get the steel pushrods. A cam isn't hard to change, I'd probably get a cam too, but that's just me. Watch rpm above 5000 it'll wear the connecting rods and eventually you'll be knocking.

Thanks Slonomo! Where do you suggest purchasing heavier valve springs, and cam? I seen some cams up of around $500 plus. That's almost as much as I paid for the entire engine lol ... What advantage will a cam do on a v twin?