Project Side Poppin'

[Jeff Clark]

I have a new toy coming and decided I wanted something different on it or not so popular I sould say... so I decided to build a side popper, I have some HS50's and H50's but I decided a side popper would fit just right for the look im going after.

I started with a very clean vintage H35

I didnt think of posting this till late so no tear down pics I just took a few tonight. This is the bulk of the parts after a days work

 

[Jeff Clark]

The engine was quite clean inside but I wanted to try and get a little more out of it, and it will need to be eye appealing when finished also. First thing I noticed was how nasty the back side of the valves looked, so I did a slight undercut and a swirl polish versus the oe casting. I also polished the stem and head.

The head in previous pic was milled then I polished the quench area and bead blasted the rest.

 

[Jeff Clark]

The block I did a clean up on the ports with a nice bowl blend trued the deck surface and finished with a glass bead in ports. The cylinder I did in a 400 finish.

 

[Jeff Clark]

A little better look at the head, I milled it polished the quench area then masked the surface, I put a head gasket on it cut the tape then blasted it.
This should lower the detonation rate and not allow any carbon build up.

 

[delray]

hey Jeff Clark i built a little side popper for my stepson and it work out perfect for him and even pulls me around. modified the tank bracket and mounted it in front of the engine to give it more of a factory minibike look:thumbsup: goodluck with your project...:thumbsup:

 

[Motra]

It has a cast iron cylinder too, not very common on the little Tecs. Nice work!

 

[Jeff Clark]

delray thats a clean unit! Motra Thanks when I tore it down I was going to do a quick rering but after seeing it was a large bore iron insert decided to play with it a bit. On the bottom of the cylinder I also cut a small radius on the edge, this is a comon practice on race engines that sharp edge plays hell on the pistons also it scrapes the oil off the skirts and adds resistance as well as heat. The piston I did a full polish the skirts it will ease resistance less friction and the top will lower the detonation rate and wont allow carbon to stick. Normally these days I coat the skirts but on this little dude reverted to the old days...

For 15 years I was doing R&D and building these things, this small little thing is actually kinda fun to me...

 

[mc73cromags]

The side pooper looks nice! They run pretty good to for a 3.5! I'll take one those procharger big block set ups for my 34 chevy! How many cubic inches are they?

 

[Jeff Clark]

Those are 540's they seem to be the most bang for the buck. I build some 622's but they get quite expensive. I did R&D for ATI in the early years on the marine side before any big units were ever made, It was quite fun back then getting the first big units to play with and seeing what I could get out of them and just plain making them work. I have made a variety of applications with them. Here is a olds

 

[mc73cromags]

Nice, those things are awesome! My friend mike has one on his 380inch duster w/intercooler, I dont know the hp numbers, but mid 8's in the quarter. Very impressive! I want one for my 34 sedan w/ 468 big block.
Good luck with the 3.5, but I dont think you will need it!:thumbsup:

 

[Jeff Clark]

Mikuni and other parts wont be here till the 13th :angry:

 

[Jeff Clark]

While waiting for parts I went ahead and hardened the block head and side cover, im sure overkill but I have the process so I did it. I also made the flange for the intake.

 

[Jeff Clark]

My parts look like they will be in tuesday by tracking so I spent a hour on it today fitting things and made the intake, I will be running a Mikuni 18mm carb seems to be the best fit for the size of the engine and intake runner, the 18 is a 22mm clamp on so the intake will have no carb flange. On the intake I made the mounting flange did a press fit with the tube and welded it from the back side then suface ground it makes for a clean finish and good seal, it's a little hard to tell in pics but up swept 3* when I get it mounted in chassis I will cut the length down some.

 

[zeeman]

Jeff, what Mikuni are you going to put on that Tecumseh? I am also wondering if you know where to get parts for the old Mikunis.

 

[Jeff Clark]

Im going to be running a new 18mm round slide for the volume of the intake and port should be perfect, I really have no clue on finding vintage Mikuni parts. :shrug:

 

[maddcarson]

looking pretty good

 

[spoon-man]

:thumbsup:I like it, Its cool to see someone Think out side the clone...:thumbsup:

 

[Jeff Clark]

:thumbsup:I like it, Its cool to see someone Think out side the clone...:thumbsup:

Thank You!! The idea I have for the whole project I think fits, I had to do a flat head and then that old side popper just kept staring at me from the corner, I think it will have style be different and run just fine.

 

[Jeff Clark]

I wasnt going to do anything cam wise to the engine I figured there were enough restrictions with air flow to get more power, but beeing up since 3am with a cold and nothing to do but think... I decided tonight to install the stock cam and measure it at the vaves to see what it even is if Im not happy with it I will contact Tim Iskenderian to see if he can do a weld and regrind. Should be a interesting little side popper when done.

 

[Jeff Clark]

The cam is .190 IN and .185 EX I would like to see a little more my head depth is .250 im thinking in the .225 IN and .230 EX range but need to do some research on the matter. At this point depending on the plug I will need to index it.