My HF 6.5 build

[suicidal4life]

Nothing too fancy here. Pretty basic ingredients. Also missing some pictures along the way

HF GX200 clone

The block is basically stock with the Gov removed and a crankcase vent added.
The head has a little more work. I removed .075 from the head surface with a belt sander and finished with by wet sanding on a piece of glass until it was true and I also did a mild port and polish job.
Flattop piston
ARC +.020 rod brought the piston up to .008 in the hole
Burris .027 MLS gasket
NRracing 285-0607 cam (Thanks to edwin on this board)
GX160 lifters
Cut to length pushrods from NR
Billet pushrod guideplate
26 lb springs
Bored 24mm GX390 carb from NR
Intake manifold from NR gasket matched to head and carb
Mikuni fuel pump
Uni filter
Robertsons H-loop header
ARC flywheel
MSD plug wire
8 degree timing key
Custom girdle
AGK head studs and side cover bolts. I also also bushed the side cover holes with steel brake line to help control movement.
All bolts secured with safety wire or cotter pins.
Noram Cheetah clutch

On to some pics

Initial teardown to check piston height

Drilled out the hole between the pushrods

Block and head painted with VHT wrinkle paint

Ready to start assembly

Checking out the rod clearance

Somewhere between .003 and .004

Checking piston to valve clearance. (Plenty of room)

GX160 lifters next to a GX200 lifter

Cam lined up (Pardon my messy job with the assembly lube)

Mocking up the girdle

Beginnings in steel

And some finished pics

 

[saychz316]

cool project.

i like the block paint job.

im not too fond of your method for milling the head, but as long as it works for you, who cares right?

:thumbsup: how does it run?

 

[AKAxAUTO]

Very cool build!!!:thumbsup: I LOVE the paint.

 

[hemigremmy]

was that originally a blue clone motor? That looks really sharp!!

 

[DEUCE]

That is so COOL.... :thumbsup: Wish I had the time, smarts and money to complete something like that. How about a picture of the whole kart.?

 

[texasfabguy]

Nice work!

 

[suicidal4life]

cool project.

i like the block paint job.

im not too fond of your method for milling the head, but as long as it works for you, who cares right?

:thumbsup: how does it run?

I know the head work is a bit ghetto but it is actually really true. With the thick Burris gasket it seals up very well. Engine runs pretty strong by my standards. Next to a MDB engine or some of the other guys on this board I'm sure it's a dog.

Very cool build!!!:thumbsup: I LOVE the paint.

Thanks

was that originally a blue clone motor? That looks really sharp!!

Yes the 5 bolt valve cover 6.5 Harbor Freight Blue clone.

That is so COOL.... :thumbsup: Wish I had the time, smarts and money to complete something like that. How about a picture of the whole kart.?

Not ready to post up pics of the whole kart yet as I haven't finished the upholstery and I still need to get it to the pinstriper for that final icing on the cake. Here's a couple teaser pics.

Before paint

And a small sample of the paintjob prior to pinstriping.

Nice work!

Thanks

 

[suicidal4life]

Got the kart back from the pinstriper so I figured I'd post a couple more teaser shots and some pics of the engine girdle as well (apologies for the dusty, dirty, fingerprinty kart and engine)

Floorpan

Steering hoop

Seat back

Engine girdle

 

[Dave_In_Florida]

Can you tell me how you were able to measure the amount of material you sanded off on the head? Did you just do it a little at a time and use a depth mic to check?

Also, what's the advantage of the 160 lifter over the 200 lifter? They are smaller, so is it that they are lighter?

 

[suicidal4life]

Can you tell me how you were able to measure the amount of material you sanded off on the head? Did you just do it a little at a time and use a depth mic to check?

Also, what's the advantage of the 160 lifter over the 200 lifter? They are smaller, so is it that they are lighter?

I used a micrometer and wrote down the measurements at the bolt mounting bosses on all four corners before starting to "mill" the head. As I progressed I would constantly check the measurements to make sure they were staying even. I also rotated the direction I was sanding fairly often to try to keep it as even as possible. The measurements never got very far off at all. When I got closer to the desired amount I switched to a finer grit paper. Once I was real close to the final product I switched to some 400 grit wet paper and did it by hand on a piece of glass. I sprayed some guidecoat on the head surface just like a bodyman would do on his bodywork and slowly finished the head. The guidecoat came off very even. There was one spot where there were still some larger scratches but they were out near the very edge of the head and not where it seals at all. I'm pretty confident the head is quite true. Honestly my job can't be too much worse then the Chinese factory does. With the MLS gasket from Burris it seems to seal very well.

160 lifters are supposed to be lighter then the 200 lifters since they are shorter. Since the pushrods are hollow the extra length they need to make up for the shorter lifter is probably still lighter then the lifter would have been. I doubt it makes much performance difference at all but for less then $10 I figured what the hell.

 

[cpu77]

I love that motor VERY Cool!

 

[saychz316]

I used a micrometer and wrote down the measurements at the bolt mounting bosses on all four corners before starting to "mill" the head. As I progressed I would constantly check the measurements to make sure they were staying even. I also rotated the direction I was sanding fairly often to try to keep it as even as possible. The measurements never got very far off at all. When I got closer to the desired amount I switched to a finer grit paper. Once I was real close to the final product I switched to some 400 grit wet paper and did it by hand on a piece of glass. I sprayed some guidecoat on the head surface just like a bodyman would do on his bodywork and slowly finished the head. The guidecoat came off very even. There was one spot where there were still some larger scratches but they were out near the very edge of the head and not where it seals at all. I'm pretty confident the head is quite true. Honestly my job can't be too much worse then the Chinese factory does. With the MLS gasket from Burris it seems to seal very well.

160 lifters are supposed to be lighter then the 200 lifters since they are shorter. Since the pushrods are hollow the extra length they need to make up for the shorter lifter is probably still lighter then the lifter would have been. I doubt it makes much performance difference at all but for less then $10 I figured what the hell.

lighter lifters is just one more thing to contribute to the greater good of the engine. if the only thing you ever did was replace 200 lifters with 160 lifters and longer chromoly push rods, then you wont see anything. but when you add this mod in with all the other things you can do, or will do, it helps make a difference.

sum of the parts is greater than the whole.

 

[copenhagen59]

I'm just wondering, but whats the wire running from bolt to bolt for exactly ?

 

[suicidal4life]

I did it more for the visual appeal but safety wiring the bolts makes it impossible for them to loosen up. It's used in the aviation industry where a loose bolt could spell disaster.

 

[jprice]

Nice Job!

 

[suicidal4life]

Nice Job!

Thanks!

 

[1BadFox]

lighter lifters is just one more thing to contribute to the greater good of the engine. if the only thing you ever did was replace 200 lifters with 160 lifters and longer chromoly push rods, then you wont see anything. but when you add this mod in with all the other things you can do, or will do, it helps make a difference.

sum of the parts is greater than the whole.

Dont you mean that the sum of the parts are greater than any individual one?
Thats a 13 or 14 hp engine at best. Not to take away from the OP by any means. But good lord...... he spent a lot of money for just a little bit above stock with air cleaner and header.

 

[suicidal4life]

Not to take away from the OP by any means. But good lord...... he spent a lot of money for just a little bit above stock with air cleaner and header.

No offense taken. I know I'm not putting out tons of power especially compared to some of the other builds on this site but I don't feel like I spent a bunch of frivolous money on this build. I could be way off base here but I would think an engine with only an air cleaner and exhaust would not be all that close in HP unless you removed the governor. As soon as you remove the gov you need a flywheel and rod for safety. Those are some of the biggest expenditures but necessary from what I've read. I got the cam, springs, rockers, lash caps, and retainers as a used set for a really good price. Not much more then a new Mod2 cam. I purchased the header used for a bit more then 1/2 price and the flywheel was a used purchase as well. I did spend a bit to get the carb, flattop piston, clutch, and a few other bits but I did my best to keep it somewhat reasonable. The main purpose of this build was to have a fun reliable engine that looked halfway decent and in my eyes I met my goal.