Lets build a motor

[lilsumo]

GVX posted on another post of mine and gave me an idea. He said build the motor yourself with advise and research from this site.

First off, this is a UMP modified motor built on a budget. It was going to be a backup to my primary, but now has to be my main.

So today I was in the garage and started working on my 421 backup motor. My Go Pro was there so i fired it up and took some clips. I will video the engine process and let you guys blast me on how dumb I am and correct mistakes I made.

First things first. I have a decision to be made. When i went all out on my motor I purchased this, Forget about the mess, I just pulled it off the blown engine.

external oil system.jpg

I also have this that i was going to run.

Internal oil pan.jpg

Since my primary motor is not going back together any time soon, probably take me a year, should i run the external pump?

[wyrmrider]

external pump for ground effects, I like it

[lilsumo]

I did a short video of me installing my crankshaft and checking clearances. The volume is low, but if I continue on I will fix that.

At the very end I talk about my piston rings and I was hoping you guys could give me some advice.

http://youtu.be/-fbKe_mGMvY

[user-612937456]

Nice start as for the rings use the .040+ rings and file fit the ring end gaps. your local speed shop will have a el-cheapo rotary ring grinder for probably $24.95 or something like that. You can make them tight per some of the recommendations but .012+ end gap will be fine unless you are planing on boost or NOS. I have to admit that I am uncomfortable with the pistons but maybe there will be some more input on them. As far as the crank it looks like you are in control with the clearances. One thing you might consider would be to remove the 3 middle main caps and there upper bearing half's and get a mag base dial indicator and check the run-out. Plus check the thrust end play while you have the indicator.

[racinnut15xm]

I havent built anywhere near as many engines as any of these guys. But doesnt that sound like a lot of clearence for the pistons?

[wyrmrider]

set the piston clearance to whatever the piston mfg says it should be measured exactly where indicated
different alloys and hypertectic take vastly different clearances from old TRW or Fordgtrues

[BigBro74]

you need to use the champ pan if my understanding of rules is correct from UMP it must be a wet sump oiling/cast iron block set up.
how hard are you turning the engine?

you may need to set the rev limiter down a ways for a 421 if that's your build as they are time limited turning them hard from what I see. I know like, everyone runs them, but even with the best stuff they don't seem to (always) last a season if 8200 rpm is the deal. too many fpm IMHO. to me 75-7600 max if 4" stroke, about 77-7800 for 3.875" stroke on a circle car. if you already do this then kindly disregaurd my ramblings J

[BigBro74]

I would also say on ring end gap, me personally, I would go much wider than .012 (if that is what was suggested im unclear), more in the .020 or a bit more. I cant really hear all that you said in the video though...... wider is safer. what does the piston Mfg. say for Circle track gap? rings look pretty high on those pistons....

[BigBro74]

set the piston clearance to whatever the piston mfg says it should be measured exactly where indicated
different alloys and hypertectic take vastly different clearances from old TRW or Fordgtrues

^^^^^^^this!

[lilsumo]

http://youtu.be/aN7dOnF95DI

I went on vacation with my family for a week, but now Im back and got another little clip.

I can use the external pump in UMP, it is technically still wet sump since the oil is in the pan. The ring gap ended up being .023 on first and second rings, according to the total seal paperwork that came with the rings.