Is anybody here running a 74 degree cam in an L series ?

I know it is not what you asked but I run a 76 in my L20.
Works beautifullt and the car is my everyday driver. Will happily idle away at 600rpm and makes max power at 5600rpm. I think the timing of the cam is a bit out as I expected the power to be higher up in the rev range.
It also makes excellent torque but comes on really strong above 4000rpm. it will still happily pull 5th gear at 2100rpm up all but really steep hills.
Personally I wouldn't bother with anything smaller.
Jake

Why does that not surprise me, Jake...

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I must have my degree's wrong..........I have some wade cam specs...it says "works 74 degree" type cam has a 4000-7500rpm range.


Somebody?anybody? Help!

dont think you do jake, i had a 74 in my previous engine and it didnt come in till 2500 and made power to 7000. I have rebuilt the motor with a 76 degree cam in it and it doesnt really have power till 3500 and so far goes to 8000 power drops off around 7800 but with the gearing i have a few more rev's are good.

Turbo510 i would interested to see the specs on your cam if it idles at 600 as mine wont go any lower then 850 without having a big hissy fit.

I run a cam which is based on a 74 degree,
Idle's happy at 800rpm and makes a heap of mid range power.
Starts to make power at 3000rpm.

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Official organisor of Thursday nite pizza.

so would that make a 78 degree cam bring on power from 2000 to 6000

Cams Catalogue Selection of Popular Profiles


Datsun 4cyl L series 1600 - 2000
Select Your Profiles from here - click >>>>>>>>>>>>>>>>



568a Ex .335
In .335 82-36
44-74 252
252 .012
.010 .507
.509 107.5 Works 74 Rally cam


479c Ex .344
In .344 70-30
40-75 260
260 .011
.009 .521
.523 106 Works 76 Rally cam

Lukey,
I think I know what cam is in my engine. It is a Wade 479c. You can see the specs in KKK289's post.
I think it is a bit advanced and I am planning on putting a vernier cam wheel on it when funds allow.
Quite a few of the Vic boys have seen my car and it does happily idle at 600rpm though it is very lumpy. I usually set the idle for 700-750rpm.
Maybe your engine needs a bit more work on the tuning as I have seen L20's with 76 High Lift cams idle at 650rpm no probs.

Lurch,
you have seen how my car runs, it is perfectly streetable so why go smaller unless you are going forced induction. I swear I am not trying to compensate for any inadequacies either.
Jake

turbo510,

Would you consider a more aggressive cam ??
Like a Crazy Racer Brown profile, or are you happy with the current one ?
I'm sure his top two profiles have more than .600 lift ( i think it's lift )

I remember asking Baz about some of those crazy profiles and I'm sure he mentioned sumthin along the lines of "piston to valve clearance" issues, meaning I guess than you needed to have deep valve pockets in the pistons. Correct me if I'm on the wrong trck.....

Individual setup will make the most difference.
I'm running a 72 works copy in a L18 and I made peak power @ 6000rpm.
Cam is very advanced so peak power could rise even higher.
A 72 cam in a L20 with same induction/ports/etc etc would make peak power at "less" rpm than the L18 due to the bore/stroke.
In a L16 I'm guessing it would be a higher peak rpm than the L18.

Is hard to compare cam's without comparing the "whole" motor.

My plans are to push the 72 as far as it cam go then move up to a 76.
All depends on the 44mm SU's keeping up really.


EDIT: Typo folks. I have not run the L18 with the 72 works on the Dyno. only the 25/65 (Great Cam). I would expect the 72 to push the peak Hp up 1000+rpm.

DatSSS73,
Piston to valve clearance is the issue in my engine with larger lift cams, otherwise I already would have gone to a bigger cam. I am planning on swapping over to ARP head studs and flycutting the pistons while the head is off so I can go for a cam with more lift in the future. But first I want to try a vernier cam gear and mess with cam timing to see what gains I can get.
Jake

What pistons are you using atm ?
I'm using 1mm OS standard dished items. Could they take a 76 cam ?

When I pulled the head from my Rally car and checked out the flat-top forgies that lived within, on every piston there was this ( shaped indent. Right about where the valves would be fully open. at some point they had come "VERY" close.

Hope you guys are using and degree wheel to set your timing.

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[quote="turbo510"]Lukey,
I think I know what cam is in my engine. It is a Wade 479c. You can see the specs in KKK289's post.
I think it is a bit advanced and I am planning on putting a vernier cam wheel on it when funds allow.
Quite a few of the Vic boys have seen my car and it does happily idle at 600rpm though it is very lumpy. I usually set the idle for 700-750rpm.
Maybe your engine needs a bit more work on the tuning as I have seen L20's with 76 High Lift cams idle at 650rpm no probs.

Turbo510, i wasnt having a go was just amased to see you get it to idle that low. Mine idles ok at 650 aswell but its not a street driver car so i prefer it to idle a little higher. The tuning has been done by with the twin 45's on and it goes a treat. Just surprised that yours runs out of power around 6000 as you say as thats when my 76 is coming on strong. Could be that it is advanced.

525C 82 42 47 77 304 304 230 230 .514" .514" .012" .010" 76 Wks.- twin carbs . Thats the specs on mine off the Tighe cams website. SO maybe its a little different im no good at reading the specs.

Luke