Streaker Build: Start to Finish

[MrC.]

Congratulations on the new addition!

Cart is awesome too.

so, let me ask you directly, how noticeable was the larger carb and intake? is it worth the money? would you say its very noticeable? if so was it more low end, middle or top end? does it require a fuel pump, or would the gravity system support it?

Thanks
MrC.

 

[Kentucky Boy]

I only used the stock carb to break the motor in for about three hours. Never drove it with the stock carb. I did however run the original Briggs flattie with the original carb then put the Mikuni on it. It made a very noticeable improvement in everything on the Briggs. I've had no issues with it at all on the Predator. I still want to take a look at the jets in it and maybe order a few bigger ones to test in it. That will actually be the next thing I do to it.

---------- Post added at 08:36 AM ---------- Previous post was at 08:35 AM ----------

It can be used with a gravity feed tank and should do just fine. I use the fuel pump due to the remote gas tank I have and it works perfectly.

I've been using two jackstands to lift the rear tires off the ground for starting. It's a pain in the rear. So I built a starting stand today. Still have to stain and seal it. Didn't try to make a masterpiece but it turned out nicely.

 

[ond]

Nice kart Kentucky Boy !

 

[Hellion]

Now this stand is for starting the engine and allowing it to warm up, maybe blipping the throttle a few times, before setting in on the pavement. Right?

Or do you have a problem with it creeping away on you?

 

[Kentucky Boy]

Yes just for starting. With the choke on the Mikuni on , after initial start it idles fast enough to engage the TQ. I let it warm up on the stand then let the back end onto the pavement and it idled fine sitting still. I've never been comfortable cold starting it on pavement with the choke on.

 

[Whitetrashrocker]

Cool.
Steal my design if you want. Less bulky.

 

[High Octane]

Nice kart

 

[Kentucky Boy]

Thanks. Actually just bought another Streaker to restore.

Been thinking about getting a 420 to put on the Streaker. If I do it will be getting a billet rod, governor delete, cam, springs, Mikuni etc... I know it will be expensive but is the 420 a good motor to mod? What's the cheapest these things sell for with a coupon? Thanks.

 

[Whitetrashrocker]

Here.

 

[ezcome-ezgo]

Merry Christmas indeed.

 

[Whitetrashrocker]

Take that 420, buy the adj timing bracket from Vegas Carts and do a little modification. Un leash the power!

I think that mod on my 301 did as much as a carb, exhaust, port and polish, and compression job on my other engine.

 

[Kentucky Boy]

cool thanks. My goal is to be able to do somewhat of a burnout with my kart. Can't do it with a built 212.

 

[Nosandwich]

The title says Streaker...still waiting on the pics....LOL.

---------- Post added at 01:03 AM ---------- Previous post was at 01:02 AM ----------

cool thanks. My goal is to be able to do somewhat of a burnout with my kart. Can't do it with a built 212.

Why not?

 

[Kentucky Boy]

Wondering if anyone could tell me if a head with the specs in the picture would work on my hemi block with billet stock length rod and billet flywheel? It's milled 0.080.

I've looked at a head from NR Racing.

Pretty pricey. Are they worth the money? Really looking for a new upgrade to do. Would like to get a milled head with bigger valves, up the compression and boost the HP a little.

I'm building a new motor for this kart. I had an extra hemi sitting around

Been checking some clearances. My piston sits 0.025 in the hole.

Checked piston to valve clearance with a 0.010 head gasket on it. It was 0.165.

Busted the motor down. Removed the governor and oil cutoff switch. Everything looks good.

Got some good parts in the mail. Still need a SS valve kit with 26# springs. Also need to get the billet flywheel.

0.020 ARC rod, Mod 2 cam, stock length CM pushrods from NR Racing.

Billet lifters from NR Racing. Stock lifter on the left and billet on the right.

 

[Kentucky Boy]

I'm hoping these lifters actually work in the hemi. The base is flared out like a valve. Any more lift on the cam and I would be worried these may bind up. Anyone ever used these in a hemi?

Here's a closeup of the lifter profile. Stock on the left.

 

[bob58o]

I'm using the NR Hemi Racing Head with 28mm 25mm SS Valves and 37lb springs.
I didn't have tools to do a valve job, mill the head, or cut the pockets for the wider springs.

Considering the head work alone... porting, milling, valve job, and cutting the pockets... would have cost me about $175 plus shipping. Save $100 if you port it yourself. Save $25 if you don't need pockets cut.

Still all that work, plus springs, SS valves, retainers, keepers, lash caps.
It would be another $75 bucks.

The way I looked at it. It would cost me $150 ($125 without cutting the pockets) to buy the parts, port it myself, and have the other headwork outsourced.

Individually, costs might look like this...
Milling $25
Valve Job $25
Cutting Pocket for 37lb or dual springs $25
Porting $100
SS Valves $35
Valve Springs $10
Retainers $10
Keepers $10
Lash Caps $10
$250

The head is definitely worth it if you'd rather outsource the head work.
I figured I paid like $40-$60 for porting and bead blasting, which isn't bad at all. $60 doesn't go too far in a machine shop.

---------- Post added at 12:45 PM ---------- Previous post was at 12:37 PM ----------

Just curious. Why the MOD 2 Cam?
And if using the MOD2 cam, you can probably use 22lb springs instead of the 26lb ones. It will be a bit easier on the rockers arms. 26lb springs should work fine, but Dynocams specifies 18lb springs for that cam (which I automatically translated into 22 lb springs on hemis, because some 18lb springs will coil bind on Hemis.)

 

[Kentucky Boy]

Been running one with 22# springs for a while now. Just trying to build this motor up a bit. I'm porting it myself. 26# valve springs don't need pockets cut. Ss valve kit with everything is $69.

Intake.

Finished my porting. Opened up the intake and left it a little rougher finish. Opened up the exhaust nicely and polished it up.

One more. Ready to have some milled off after I figure out how much.

 

[bob58o]

What type of fuel do you want to use?
Since the cam is low lift, the fuel octane will probably limit how much you mill.

+0.020" Rod (.005" in the hole)
3 stacked gaskets (0.027" thick for 0.032" P2H clearance).

Mill 0.040" and you should be at 11:1 CR.

I try to use 100 Octane with 11:1, but lately I've been using 93 octane with Royal Purple Fuel Stabilizer/Octane Booster. You can probably get away with Premium Pump Gas and 11:1 CR.

 

[Kentucky Boy]

That's cool Bob. I've been wondering about how much I can take off. I'm going to put in the new rod today and take some more clearance measurements just for safe measure. Thanks for that info! I think I may only use two stacked gaskets for 0.025 Piston to head clearance. . I'm pretty sure that's the clearance in my other hemi and have had no issues with it. I'd like to be able to use pump gas but I have access to airplane fuel that I think is 110 octane. I could mix it in with some reg fuel if needed.

Here is the valve package I'll be going with. Can get it with 22# springs or 26#.

Got the block cleaned. Clearanced the crank and the cam. Checked rod bearing oil clearance. Installed the +0.020 rod, billet lifters and chromoly pushrods. Now the piston sits only 0.005 in the hole.

 

[Nosandwich]

THAT outta work.