rebuilding after the crash

It ain't a cheap date. I'm not getting any younger. I don't know how many years I have left doing this. I want to hit the loud pedal and see flames blowing out of the pipes as high as the roof before I hang it up. I figured why wait.

 

With the extreme cylinder pressures a nitro engine sees keeping this pressure in the cylinder requires extra care.
Stock gaskets won't last a spit second.
Solid copper is used. A groove is cut in the top of the cylinder. A matching groove is cut into the head. A ring of stainless wire called a hoop is inserted into the heads groove. It sticks out above the heads deck. When the head is torqued down the hoop pushes the gasket into the receiving groove in the top of the cylinder. This provides the seal. The cylinders are set .004 above the deck for the ultimate seal. A little rtv around the oil return holes eliminates a oil leak.

 

Those heads are a work of art

 

DDDenny the intake ports are extra large to accept big bills to flow through easily. The volume consumed on a pass will go up a few gallons per pass.

 

Money exchanger

 

Well that didn't take long I just had to see what they looked like on the engine.
Actually I need to mock up the engine because the car is going back to the chassis shop this week. I'm going to start the car off the blower now. The fuel tank needs to be moved to make room. I'm also adding capacity to the tank. What looks like a large funnel will be added to the bottom of the tank. It will add about 2.5 gallons for a total of nine gallons. Even this much is cutting it close for a quarter mile.

 

I've heard of "o-ringing a block" to increase sealing, and the "hoop" sounds like this. The cylinders being set above the deck height is new to me though - is this the cylinder liners, like the drawing below?



Cheers,
Harv

 

The blower starter. Starting a nitro car requires this starter. It's powered by 48 volts. Nitro engines have fixed timing. There is no advance. To keep the engine from rotating backwards this starter and 48 volt battery pack is a must. The starter can also be used to spin the engine for oil pressure just before the ignition is turned on. The starter locks into a cage mounted to the blower. The round handle moves a dog into a dog on the blower pulley. The engine is fired and the starter dog releases. The starter is turned to disengage it from the cage. Off to the starting line.

 

Yes harv that's it. I ran my sleeves even with the deck when I ran water like the top pic. Now I don't have to worry about that I'm going for the max in sealing. This will also help prevent gaskets getting pushed out. I pushed a few out trying to both street drive and race the car in the past.

 

Oringing is similar to hoops.
A normal stainless o ring comes from a spool of wire. Usually around .035. The wire is set in the groove and butted together as close as possible.
A hoop is a piece of tubing cut off at the desired length. It's set deeper into the head. It's slightly larger that's why the sleeves receiver groove needs attention.
It's the same idea only the better modern way of doing things. The hoops are less likely to push out torching a head; block or both.

 

Many thanks - I learned something today.

Cheers,
Harv

 

A follow up to the discussion about mag drives. This is the most modern design. It's what used to set my mag up.

 

Like a kid on x Mas morning I had to go out to the shop and mock things up. There were questions on the manifold if it would fit on the heads. The other question was the ports if they would line up. Good news it all fits. I can keep my manifold.
It's a big deal because mine fits a 8-71. A Allen Johnson is for a 14-71. A adaptor plate would have to be used to cover up the huge opening. Plus it saves me huge cash.
I just got a notification from ups. More parts arriving tomorrow. Too bad I work 12 hrs. I can't wait to put this part on. The car is mocked up enough for the chassis shop.

 

Harv that's what it's all about. A exchange of ideas and learning new things. It's more fun for me that way. I learn things from the guys on this site and others sites here. Cheers.

 

Sorry to go over same point but I know stainless wire around cylinder but you cut that wire to butt close at ends. Hoops look like one piece no end just a perfect tight fit in groove. You can find & get right size hoops for groove. Is that right. Sweeet heads unreal.

 

Since ur going full race I think it'd look killer if u got a grill shell on there again and ran a vertical tank in there for fuel. I know it's ur car but it would look great with a shell to complete the front end with an aluminum tank crammed in there. Ud also be able to carry more fuel.
She's ugly(my photoshop skills)but u get the idea. I always love that look of the hollowed out grills with sheet metal, colored lexan, or a moon tank.

 

Hey, Brian;
Looks just killer. All that stuff just makes me smile, I can momentarily go back in time to when you fired the rig off for me at the Bttt50's. It's just too bad I messed-up the recordings, & for some reason the camera shut down 99% of the sound - of course, nothing could/would capture the physical impressions(exhaust pulses, motor sounds) & smells. I found a new addiction that day. . I also remembered the nitro smell from my gas-powered-model-airplanes, but yours' was so much better! & any other loud exhaust has become just that - an annoyance. There was one nitro-funny the next yr at the Btt50's, but I knew what to expect. . I do believe I'd like to hear both of you two, doing a "dueling Nitro exhausts" session. Banjos indeed...
& thanks again for putting this info up. Only way I'll ever get to see it.
Marcus...

 

The hoops are bore specific. In my case 4.187
The grille was destroyed in the crash. There has to be a chassis bar offering protection to the tank. Something they didn't do in the old days. I get what you are saying it just won't happen.

 

Those heads are KILLER. I could probably fit my whole closed fist into those ports

 

go big or go home. i had the best heads for the street now i have the best for the track. it didnt come easy i worked alot of over time to get where im at.

 

So, with the "hoops" cut off from tubing, is the cross section square or rectangle vs round for an o-ring?

And what is the hoop material? Stainless steel also?

Who supplies the hoops? Are they stock items? Or custom made to order?

 

They are made from tubing. The end is machined to be round. Maybe from a lathe I'm not sure. It's cut off at the correct depth. Usually around .070. That end is square. They are bore specific. When installed they look just like the old stainless wire they just don't have the tell tale line where the two ends meet. They can be ordered from cylinder head companies. I don't think you will find them at summit or jegs.

 

Thanks for that info. Been thinking on how to eliminate the butt-seam in the o-rings. Looks like that issue has already been solved by using these hoops.

And as already been mentioned many times - Thanks for taking us along on the ride with you. Lots of interesting info you're sharing.

 

Man, this thread just keeps getting better and better.
Nitro Evolution!!

 

Alot more to come.

 

Big enough to suck in pigeons, or small children.

Cheers,
Harv

 

Keep the tech coming Brian, very interesting stuff, and FUN! Are you going to tip the can a little more with this combination?

 

Better put some of that "moonshine" in there!