Advanced Hemi 212cc Predator Build

[bob58o]

Conciseness...
I'm learning!

---------- Post added at 10:24 PM ---------- Previous post was at 10:19 PM ----------

104 Lobe Center Line
22 overlap
230 duration
.275 lift
(0.05" event timing)...
Intake open 11 BTDC
Intake close 39 ABDC
Exhaust open 39 BBDC
Exhaust close 11 ATDC

 

[Jrgunn5150]

I'm merely speculating, but I bet 3600 rpm, is very near the stock cam's TQ peak, and thus the reason for the governor RPM.

 

[Poboy kartman]

I'm merely speculating, but I bet 3600 rpm, is very near the stock cam's TQ peak, and thus the reason for the governor RPM.

I can't say for sure...but in the back of my mind...I'm thinking every engine has the same hp and torque curve meet at about that rpm....

What does that mean? ...Time for me to shut up and get some sleep.

 

[Jrgunn5150]

I can't say for sure...but in the back of my mind...I'm thinking every engine has the same hp and torque curve meet at about that rpm....

What does that mean? ...Time for me to shut up and get some sleep.

HP and TQ cross at 5252. HP= TQ x RPM / 5252

 

[bob58o]

so how's your project coming there Bob ???? Mine still sucks. Hahaha. Lol

But to answer your question I just took the bar stool from 1900 RPMs to 2900 RPMs and it's actually a lot faster. The ideal time for it to shift into high gear would be right after the peak torque RPM of your motor

As far as I know. It is good. No holes in the piston. 30% increase in RPMs. Flywheel still in one piece.

 

[bob58o]

HP and TQ cross at 5252. HP= TQ x RPM / 5252

Which is why I say HP isn't real. It is just how much torque at a certain RPM!

https://www.youtube.com/watch?v=iE8CJwXSPRs

---------- Post added at 01:56 PM ---------- Previous post was at 01:51 PM ----------

Well...Bob....I could probably help you....BUT...I don't want to peruse 70 pages of Encyclopedia Jr. to find your cam specs....refresh my short term memory....(Cliff Note version please....)

Give me the answers!!!:toetap05: LOLOLOL

---------- Post added at 02:37 PM ---------- Previous post was at 01:56 PM ----------

I find this amusing...
http://karting.4cycle.com/showthread.php?50340-torque-motor-or-hp-motor

 

[Jrgunn5150]

I've long been of the opinion that you cannot make big HP without making torque, or vice versa. You build the best engine you can afford to and let the chips fall where they may.

If you have HP, you will have torque. If you make 500 HP at 6500 RPM, trust me, that engine isn't boring at 3000 WOT either.

It's part throttle where tuning comes into play, and the combo makes it either a pleasure or a penance to drive.

 

[bob58o]

I've long been of the opinion that you cannot make big HP without making torque, or vice versa. You build the best engine you can afford to and let the chips fall where they may.

If you have HP, you will have torque. If you make 500 HP at 6500 RPM, trust me, that engine isn't boring at 3000 WOT either.

It's part throttle where tuning comes into play, and the combo makes it either a pleasure or a penance to drive.

What is part throttle? My engine doesn't know what that is. Lol

 

[bob58o]

While you all have been avoiding my band brake questions like the plague, I went to go take a look because the band and drum/hub should be here today.

Tickled pink that I only have to remove one wheel hub!

I imagined having to pull the whole axle. I can fit the drum on the outside of the swing arm and think it will be just fine while I work on the hydraulics.

Once It gets here, I guess I will figure out if a cable and pedal spring is all I need or If I need another return spring on the band.

 

[bob58o]

Right deer on the left.

 

[bob58o]

Did I mention for the millionth time how much I love my 1.25" solid steel fully keyed 48" shaft from McMaster Carr?

EDIT: This old picture with the original 40T tooth sprocket has me thinking about the the 420 gearing options.

---------- Post added at 01:54 PM ---------- Previous post was at 01:27 PM ----------

I guess I like the 6:1 with 18.5" Tires and a 40 series.
61 MPH at 6000 RPM
33 MPH at 3200 RPM
300 Lbs force at Launch


Now.

Assuming 600 Lbs weight with driver...
60% of the weight of the back tires
30% on each rear tire

180 lbs on each tire

Coefficient of static friction for tires and dry road 0.7?
http://hyperphysics.phy-astr.gsu.edu/hbase/frict.html#coe

Force of Friction = (0.7) N
N=mg
Force of Friction (for each rear tire) = (0.7)(81.65kg)(9.81) = ~560N
Times two Tires = ~1120N

27 Nm at crank * 6 * 2.45 = 397 Nm at axle
0.235 meter tire radius
397/0.235 = 1690 Newtons linear force

Minus 20% belt loss.

= 1351 Newtons at the street vs 1120 Newtons of static friction between the rubber and street.

Burnouts?

Admittedly the math may be flawed.

Give me the answers Bro!

 

[ezcome-ezgo]

For $115 I certainly hope you love it.

Smokin' Newtons!

 

[bob58o]

https://www.youtube.com/watch?v=425GpjTSlS4

---------- Post added at 02:52 PM ---------- Previous post was at 02:41 PM ----------

Missy is covering my shift tomorrow so I can play all day.
Brakes, steering, and fuel in the bowl means I can get to the jets, spark plug, tires, TC settings, and then eventually 420cc the battery, winch, alternator.

I may take the New fronts and use them as temporary Rears.
The old rears and new fronts are about the same size ~16".

I'm not really sure I want the bigger tires. I will test and see what I like.

 

[bob58o]

Brakes

 

[bob58o]

The beginning.

 

[bob58o]

Then maybe weld a bolt on like so...
????

 

[bob58o]

So when brake pedal is pushed, the cable pulls the free end towards the swing arm pivot.

 

[Jrgunn5150]

Seems logical to me.

 

[rk970]

Make sure the cable pulls in the direction of rotation. its called "brake self servo" the rotation of the drum will help "pull" the brake lining tighter...
I would drill a hole through the frame rail and use a longer bolt welded on both sides.
rk

 

[chancer]

I have used band brakes, and installed a return spring on the band only. none on the pedal.
I also only use a rod.
I did not mean to avoid your question, but I do not think I was doing them correctly LOL.
So I did not want to spread bad info around. But I dunno my brakes work.