Class 9 Engine Questions

[mike_hinson]

I am currently building the engine for my 9 car. I am looking for advice on how far to go as far as reliability and horsepower go. With the the claimer rule, I am a little hesitant to put too much money into it. Machining the case cost $250 alone. I'm just looking for a little guidance. Some of my questions are: Do you use cast or forged pistons, stainless or steel valves, what weight flywheel, total seal rings, clutch & pressure plate type, chromo pushrods, balancing, cam selection, etc.
Thanks in advance,
Mike Hinson

 

[AllwaysRcn]

Personally I always go with "Total Seal" rings for sure.

 

[Protech975]

Mike
Don't worry about your engine getting claimed, you are one of the good, honest guys and
we don't get Engines claimed! Hopefully.
AS for the engine I would go all the way or until your engine budget runs out, I ran Cast Piston and cyl. Stainless valves,Total seal rings only after the first leak down and the Cyl, were broke in, chrome push rods. we balanced the rods, pistons and fly wheel. and I ran a VZ14 cam. right out of the box.
keep the flywheel as light as you can. and you should have a strong reliable engine. the last one I built from scatch cost me $1,250 we had 5 races on it and the leak down showed 1% drop in comp.
I do a leak down and dyno every 2 to 3 races just to keep track of any change in specs. Rob S.

 

[TimHayosh]

Here's some of the stuff I used:
Mahle forged pistons (incl cylinders and pins): $165
Kartek "1600 Race" rods.
Bug Pack valve springs
Stock push rods (they're light and hold up quite well).
Stock push rod tubes
Stock crank
Stock fly wheel with gigantic nut. W/dowel pins
Gene Berg full flow oil pump cover
Melling oil pump
Windage tray (Very important)
Cam; I never did know! It came with the car, and the original builder shaved off all identification.
Kennedy Stage I clutch and pressure plate.
All ignition components were MSD.
Case savers.
Also had some magnesium gussetts made for where the case transitions from horizontal to the bellhousing.
Rear engine mount!
That's all I remember.
All I did was change the oil and plugs between races. Never a single powerplant failure in 2 years. Thanks <A target="_blank" HREF=http://www.ce-vw.com>Competition Engineering!</A>

 

[Protech975]

Mike
Any reason you did not use a lightened flywheel? With such low compression that we have to use I have found it to be a must in order to get the revs back up quickly. Clutch is great so long as you stay away from racing or puck disks"Pinion Breakers".
We also ran a Compu-fire ignition and never missed a beat,ever. 14 races in 2-1/2 years and not one engine related failure. These engines are so tame that as long as you keep them tuned and tested they will run forever! Any stories about engines that have lasted for a long period of time racing? R.S.

 

[mike_hinson]

Rob,
I am using a lightened flywheel. I will weigh it when I get it back from RIMCO. I think it is 12 lbs. Sent crank to be ground, 8 doweled and balanced. Sent four rods to be rebuilt and balanced. Sent flywheel to be 8 doweled and balanced. I will have pistons balanced in Bakersfield after I buy them. What manufacturer and grind cam does everyone run? How about straight cut cam gears? The price keeps going up.
Mike

 

[AllwaysRcn]

My last one lasted about 2 years-ran perfect-UNTIL-racing the superstition250 night race in Oct., 2 miles from the finish, 2 minute lead, and that big red oil pressure light came on. Thats when life stops for a second and you have to decide if you want the win or a not so damaged motor. Well we (I) wanted the win so we tried to do a 20 second (add oil and go) at a strategic point on the coarse. but it was to late. When they tried to add oil, the pistons had such big holes in them, the blow-bye just pumped oil right back out of the breather. needless to say I had to start over from scratch for the New Years Eve race (case and all). OUCH! I think I will try a standard tear down every season now. I "leak down" every other race. I change oil (Syntec) and plugs and filters, Etc. every single race no matter what. If nothing else, for a piece of mind!!!!

 

[Protech975]

Mike
I am no expert by any means just a Garage Mech. that has been racing off and on for 25 years. I first started out racing the OLD HDRA Class 11s."Budget Bugs" Can you believe we actually ran stock 40hp engines, one shock per wheel in the stock location. I built my own Engines and transmission's from scratch and with used parts when I could get by with them and in 3 years racing never had one fail!
As for the Stright Cut Cam gear hear is what my Engine man told me,"Riffle Racing Engines" the straight gear does not cause side load on the cam bearings like a stock gear will and on a Dyno will actually show 3 to 5 more HP because of less load on the entire engine. So I would say go for it.
I also only ran a stock Doghouse oil cooler with an external oil filter mounted close to the engine. I only had my oil light come on one time during a race "Flicker" and stopped to find the valve cover gaskett was leaking, we always had a new cover with gaskett attached in the cockpit ready to just slap on and we did and won the race by 4 Mins. Engine showed no damage. RS.

 

[mike_hinson]

Rob,
Flywheel is 11 lbs.

What cam grind do you guys out there use?

Mike