What to switch out when using a 308 cam

T

Timeismoney

Member
What would I need to upgrade if I put a 308 cam in my Lo206.
I also ordered the blue ignition coil & beefy billet rod.
If springs are needed which size should I get?
 
Dyno Cams says you need 36# springs for their 308 cam, they sell a 36# dual spring kit for animal motors. Available at other retailers also.
 
The newer (larger) Briggs rocker studs can handle them, but don't try running those springs with the older (smaller) studs and rockers.
Also depends how big you're planning this build...a set of roller rockers can be a wise investment, especially with ratio built in and hopes of eventually going to bigger valves, bigger carb, etc.

-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
32 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
 
All I’m trying to do to my built is
Flywheel, billet rod, 308 cam, blue ignition coil and bigger carb.
Would I be good with just that or I’ll need more parts to keep it Durable?
The rockers cost a arm & leg
 
CarlsonMotorsports said:
The newer (larger) Briggs rocker studs can handle them, but don't try running those springs with the older (smaller) studs and rockers.
Also depends how big you're planning this build...a set of roller rockers can be a wise investment, especially with ratio built in and hopes of eventually going to bigger valves, bigger carb, etc.

-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
32 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
Click to expand...
What size are the bigger studs?
 
Brettm57 said:
The 36 pound like Dynocams recommends.
Click to expand...
Unless you are using ratio rockers, the cam maker recommendation is where you need to be.
Obviously, they know their cam better than anyone else.

Of course, change any parameter, the spring required changes. Obviously, need to use the spring which allows valve control in the rpm range required, without undue drag.(read that as frictional losses without gain.)


Ie, this is where the final .25 hp comes from, if you are searching for that.

Titanium valves require less spring pressures to control valves. Less rpm also requires less pressure. Cam profile demands a certain amount of pressure to control valve.

Most can be satisfied with a baseline setup, and tweak chassis for the last bit. (This is where it is at, anyway.)
Of course having a slight engine advantage adds confidence, if little else.
 
Last edited:
Timeismoney said:
All I’m trying to do to my built is
Flywheel, billet rod, 308 cam, blue ignition coil and bigger carb.
Would I be good with just that or I’ll need more parts to keep it Durable?
The rockers cost a arm & leg
Click to expand...
The stock PVL flywheel is fine. A nice upgrade could also be a pop-up piston.
 
Last edited:
racinnut15xm said:
What size are the bigger studs?
Click to expand...
They've come on the engines from Briggs for a few years now. 8MM, as sundog pointed out.
All you need to replace is the stud plate to use them - of course the studs, rockers, and adjuster nuts as well.
Some use an aftermarket stud plate, but it isn't necessary for a mild build like the OP's.
We keep the Briggs stud plate and all parts in stock.


-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
32 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
 
CarlsonMotorsports said:
They've come on the engines from Briggs for a few years now. 8MM, as sundog pointed out.
All you need to replace is the stud plate to use them - of course the studs, rockers, and adjuster nuts as well.
Some use an aftermarket stud plate, but it isn't necessary for a mild build like the OP's.
We keep the Briggs stud plate and all parts in stock.


-----
🏁Thanks and God bless,
Brian Carlson
Carlson Racing Engines
Vector Cutz
www.CarlsonMotorsports.com
Carlson Motorsports on Facebook
32 years of service to the karting industry ~ 1Cor 9:24
Linden, IN
765-339-4407
bcarlson@CarlsonMotorsports.com
Click to expand...
Can I get a link to stud plates
 
I do not know who "they" are but the 206 flywheel can handle anything you will be able to throw at it with that cam and a stock carb... Certainly convert to methanol. What are you using the motor for?
 
Last edited:
Chipg56 said:
I do not know who "they" are but the 206 flywheel can handle anything you will be able to throw at it with that cam and a stock carb... Certainly convert to methanol. What are you using the motor for?
Click to expand...
I run 91 not really trying to switch that either
But guys I ride with told me and also seen it online. That’ll you’ll atleast need a billet rod and flywheel if you switch coil
 
I don't mean to get this thread off track, but what RPM are you guys bringing your clutches in with 308 cams? We were at the track yesterday (sprint/road course track) and trying different RPM's, but it was so cold we couldn't get the grip in the corners to make a good determination.
 
  • Like
Reactions: HGM
You must log in or register to reply here.
Back
Top