stage 2 drivability

[stage274]

I have a complete 274 busch motor , from intake to pan , full dry sump, alt,strater,with a 100 miles on it, I need help with build up , i would like to keep my dry sump set up , just because its bad ass, I need help with a cam choice, I want this thing to be drivable to car shows and such, I know I should go with a solid roller , but I heard that you , you have to rebuild the rollers after x amount of miles, how feasable is a flat tappet cam non roller, does any body make one for a on center motor, I would like a traceble Idle, I am putting this motor in a 2002 colletors edition trans am, that was a theft recovery, so drivabillity is a concern, does any one else out there drive there stage 2 headed motors .I would like to have the car runing low nines occationally, with good Idle quallity. also is the dry sump reliable for street duty.

 

[Bob Mustic]

Stage II on the street

Well where should I start? First if your motor is like mine ie a normally aspirated 274" Stage II motor you will go in the 9's if you drop the car into a mine shaft. Unless you use a LOT of nitrous. Also you talk about street driving but how much is your compression. I believe the average Busch motor had a compression ratio of 14 to 1 (or higher). In my Cobra we lowered the compression down to 11.5 to 1 which works well on the street. I also use a Weaver dry sump system on my car and think its the best oiling system going. I've had zero trouble with it. It has an idleing oil pressure of 55lbs and at 8,000RPM its just a shade above 100psi. This is with Mobil 1 10/30 oil.

By the way the Cobra runs 10.8's and weighs 2550 with me in it so your trying to get a Trans Am into the 9's is a pipe dream normally aspirated, IMO.

As far as the idle goes I use a circle track cam (Reed Cams) that pulls hard from 2500RPM with a peak of 390 ft/lbs of torque and 473 HP at 7600RPM. Also your probably running Titanium valves but you should replace them for street driving as they WILL fail at some point.

The above cam idles at 800 RPM very well. Motor runs extremely cool on the street. At 85 degrees in traffic I never turn the radiator fan on and I've never seen the temp get past 185.

Bottom line is, again IMO, I'd go to a SBC for the Pontiac. The Stage motor in normally aspirated form is perfect for a very light car IF its modified correctly. By the way I did not have the answers on the mods. I relied on guys like Chuck Leeper, Steve at Reed Cams, and G. Grimes to show me the right direction and I have to say they knew exactly the right combination, IMO...

Hope this helps,

Bob

 

[stage274]

I look into turbo charging the the ls1 , its a awsome motor,but it wont produce the numbers I like to see, they have a hard time getting past the 600 horse mark at the rear wheels , and that is with heads cam and turbo system, I was going to lower the compression of the stage , I figure the heads of the stage has between 33-40 cc with a 6.5 rod , I have done the math on what size piston I need , je make a piston with 1.2 comp hieght and a 50cc dish, that should bring my compression to 8.5-9.2, depenting on the cc of my head, I want to run 800 horses with 800 pounds of torqe, but I want the motor realiable , unlike the ls 1, you would need a c5r block billiit crank rods and c5r heads , that will cost over 30000$ dollors for the same streangth as the stage , plus I would have a 2002 turbo trans am. and how cool woud that be.

 

[GNSCOTT]

To clarify, are you talking about converting the bush motor over to a turbo motor? ie. changing piston, cam, ex valves, springs, converting to FI etc?

Solid roller cam at best will weaken the springs quickly with street driving, and will eventually destroy the lifter. I'd go with a hydraulic roller. I was thinking of doing the same thing with my old 02 WS6, but knew I wouldn't have the patience for it.

 

[Bob Mustic]

GNScott your on the right track. Trying to take a Busch motor and convert it certainly is possible but why? Put a SBC Chevy in the car and with the right heads it will do everything the Stage motor will and be a LOT cheaper. IMO, of course...

As I said previously I've used a Stage II motor for my Cobra and I love it. BUT I didn't reinvent the wheel with it either. Lower compression different cam grind and some minor other stuff worked great. BUT I wanted a "one of a kind" Cobra and since John Spina already had a GN motor in one I thought I'd like to do the N/A Stage II.

To each his own though. If that's what you want go ahead but your going to have a TON of money in the conversion. Just ask the guys on this board who have done it.

Regards,

Bob