Thread: Thoughts on a full race motor setup

There is an Australian company that makes harmonic balancers. The will custom make them to any size, width, belt profile, how ever you want them they will build it. They also offer a lifetime warranty on them no matter what the application including racing. They are however pricey as you can imagine. I think from memory they are in the vicinity of $800 AUD. But I suppose if you are sinking 5k+ into a motor $800 is nothing compared to the cost of the vibration loosening your rod bolts.

:| ROSS Tuffbond |: - ROSS Racing, ROSS Balancers, Heavy Duty Harmonic Balancers, Automotive Parts, Bus and Truck Components |:

Is the issue with the 4cw crank its vibration i.e could a decent harmonic balancer fix it or is it the vibration problem due to the 4 cw cranks lack of rigidity

i personally will never run an undampened front pulley, and the only time i would upgrade is to a heavier one like ross

hmmm so what's the alternative for guys who are running pulleys? I know LOADS of them,....no I mean us, are.

Drop the lower oil pans and re-torque rod bolts every X amount of miles?

I know I'm late to this discussion. I tried to stay out of it as best I could. I admittedly haven't read most of it. Also, I'm not trying to pick on Andreas or anything (God knows I don't need to keep arguing with him over tiny stuff) but this caught my eye:


If the pistons/rods counterbalance each other, then why are the counterweights there at all?
Okay forget that question because that's just too open ended. How about this. I know you know that the counterweights are there primarily to counterbalance the pistons and rods. Are you trying to say that the counterweights have an easier job of things if the pistons/rods are balanced with each other to begin with?

Also I'd like to add to what mrslappy said about harmonic dampers.

I agree. I know I spent a long time maybe a year ago arguing that harmonic dampers were useless. That was before I learned enough about them. This is the second time I'm coming out in favor of them.

The biggest problem is not mentioned which is a large crank throw. When the rod journals are far from the crank center line you get much more rotational flex between each crank shaft arm. Rotational flex between each crank shaft arm is the problem harmonic dampers try to remedy.

The statement above really needs to be about torque, not horsepower. High torque creates high crank harmonics, not high horse power.

Funny you mentioned about the rod bolts. I ran a Toyota 22R about 20 years ago. long story short, a poorly lightened and balanced crank, aluminum undampened front pulley, Rod bolts by Pepco (I think) ARP did not make bolts for foreign motors then. While the assy. was balanced I think the machine shop (v-8 shop) gave up after a while trying to balance the motor. This was the result.



One of the rod bolt nut was found in the oil pan. It ran for two race weekends before it let go during a test session. What a Torque monster it was...

I want you guys to know how lucky you are to have all these parts (while still expensive) available. The SR-20 is way better designed motor than the 2,3t, 22r, or lb20 motors. You can get away with more than we did back in the day.

I went to the PRI show over the weekend. I saw a guy walking around with this piece on his tote bag. I chased hin down and had to snap this photo. It's for a Honda. Made of carbon and aluminum, beefed up for about 35 psi of boost. Its still in the development stage. May retail for about $1200. The guy was not sure if it will make to market. That's what it's going to take.

that intake manifold is not anything new. i had one to dyno test over 3 years ago. very nice piece i must say

Looks to me like the angle of the TB flange could use a lot of work. But what do I know. =/



vs.

You cant build that manifold design in a FWD car.

You can build the plenum design on a FWD car. Intake on the rear (SR20) or intake on the front (Dodge and some Hondas).