L20B Race cam Ideas

[GreaseMonky]

I need to change the cam in my L20B the cam now I guess is from Bills Datsun, and has a chip in one of the lobes, pretty good size, I cant change springs, or do any port work yet, but I want to put the largest cam I can and. I run High rpms durning the race I am looking at a cam with these specs

 

Lift is .480/.480 duration is .292/.292, and lobe seperation is 108

 

 

 

I am limted to a single carb, any 2 barrel, and am thinking about going to a holley 350, or 500 cfm

[banzai510(hainz)]

any 2 barrel??????? you sure.

 

if regulated by this I would try a DCOE or Mikuni sidedraft with a LYnx manifold.

 

 

the 350, 500 idea I think the stock manifold cant really flow it as good as the air comes in and has to make that sharp 90deg bend. ,I think it would slow down the airflow.

Could try a weber 38/38 and match port it best you can.

 

isky makes cams and Webcamshafts.com has a 488 252 duration cam and others.

I dont know your valve train set up and lash pad selelction or if you have spares so alot of this is just a guess on my part

 

isky might have the cams in stock others they might have to grind and a few weeks to a month wait time

 

 

Schneider made cam but only do regrinds now. No more new cams. they had a Asymetric profile what I seen

[GreaseMonky]

no side drafts, it has to be a stock style downdraught manifold, valve train at this point is mostly stock from what i can tell

 

 

[banzai510(hainz)]

.480 is near or collasped coil at the height

[Cheater Dan]

For what its worth, we raced 510's with the stock head, holley 350 rule many many many years ago.

We stumbled across an assemetric cam made by DL Potter in Mitiplas California.

I can't remember too much about the grind numbers (28 years is a long time)

I think he called it grind 5 or 6 ???But that thing made absoutely incredible power from 3500 to about 7600.

It was a wierd thing to time but...

The car ran on the pavement and when we got told to not come back with it it ended up on the dirt and did just as well.

FWIW maybe hes still around, was a real curmudgeon when I dealt with him, in a good way.

He sure knew his stuff.

[banzai510(hainz)]

Don Potter held his cam secrets.

I talked to him about 15 years ago. Dont know if he is still even around.

 

He claimed he had a a cam and with stock SUs would beat a Vtec Honda civic. I personally found that hard to believe