34 replies to this topic

[slar]

Hey all.....my engine is in being machined as we speak......bored, honed, squared decked, flat tops, full rotating balance.

 

304 carby, VN heads........im told the compression ratio will be about 10.3:1 when finished with standard un machined heads.

 

I will be using one of the standard VN carby manifolds...ie Come, Redline, Harrop etc.....I haven't purchased a manifold yet as I need info on a good cam ---manifold combo before I make my decision.

 

So please offer your advice or specs that you know work well with a 304 carby VN headed engine.

 

Thanks Al

 

[torana_nick]

I have similar setup with a torque power manafold and a crow cam equivalent crane 286 cam. Can't realy comment on how it goes yet as I haven't driven it.

[Ice]

The 286 is ok with an auto but with a manual i would go for the the Crane 288 with an Edelbrock performer manifold good electronic dizzy for the street that would be sufficient

Oh a good set of diff gears

[slar]

Thanks Gene will do a bit of research on it.

More info on set ups welcome

[rexy]

Do you want to keep it under the bonnet? This will limit your intake choices.

[Redslur]

The 288 solid is a pretty grumpy cam and will need good engine enhancement to make it worth while. While the 286 is a hydraulic and great street cam for mild applications.

[slar]

Do you want to keep it under the bonnet? This will limit your intake choices.
Yeh rexy inder the bonnet preferably

  

The 288 solid is a pretty grumpy cam and will need good engine enhancement to make it worth while. While the 286 is a hydraulic and great street cam for mild applications.

Just to clarify Red....is the 286 your talking about known as the crane compucam H286
Cheers Al

[rexy]

If you want it under the bonnet then both the COME and redline hi winder will fit.
I don't know of anyone with a torque power or harrop that's under bonnet. I have an Active manifold in the shed and it doesn't fit either.

[Ice]

Yeah the 288 Crane is pretty angry the 286 will be more than ample to do the job in a Torana

[torana_nick]

If you want it under the bonnet then both the COME and redline hi winder will fit.
I don't know of anyone with a torque power or harrop that's under bonnet. I have an Active manifold in the shed and it doesn't fit either.

I have a low rise dual plane it looks like it will fit under the bonnet but i haven't fitted an air cleaner yet.

[rexy]

Brain fart. I was only thinking about single plane manifolds.

[slar]

Ok thanks fella's.......seems like the low rise dual plane manifold with a H286 cam seems to be the good mid power setup.

Been researching on the net and just about every auto forum dealing with holden V8's seems to point to this set up over and over again.

 

The only thing that made me ask this question about cams for a 304 was my engine guy asked me what cam I would be running and I told him probably a 286.

He said nope....good grind for old style heads but not so good for VN heads with their over sized intake ports compared to the exhaust ports.

 

He said the 286 was an equal cam ie 230 -230 deg @.050 lift- gross lift .496.......he then said the best cam for a street engine (carby 304 with 10:1 comp) was a

split cam 214-224 deg @ .050 lift- gross lift .490 he said it needs more duration on the exhaust port.

 

Does any of this sound correct.....Im not really up to speed on camshafts so Im trying to learn.

Can some one explain the differences between these two cam grinds.

 

Cheers

Al

[Struggler]

A quick explanation is.....

 

Yes the VN head is biased toward the intake, flow wise. If you wanted to compensate for the average exhaust port by increasing the exhaust duration then be aware that this will bleed off compression and therefore torque lower in the RPM range, not good for a street engine.

 

Increasing exhaust duration will however make more upper RPM HP and stop the engine nosing over after peak HP. This is desirable for an engine intended to operate above about 6000 rpm.

 

Personally I have found that single pattern cams will make more torque and be more responsive in a street application, regardless of the head used. Once the owner wants to rev it up and make a bit more HP at the expense of mid range torque then by all means give it some more exhaust duration.

 

Short answer..... the 286 will be fine and really is hard to beat in any street Holden V8.

 

JMHO

[Redslur]

The comments above are from a man who know his 308's so I would listen to what he has said.

 

From my experiences, the Perfomer (dual plain) and Crane H286 hydraulic is probably the best set up for a good streeter 308. Not had a H286 with a VN headed engine but from all accounts I have heard, they also work well.

[slar]

who is building it?

Gday......Im putting it together but machining is being done at Pryce Engines Newcastle

 

A quick explanation is.....

 

Yes the VN head is biased toward the intake, flow wise. If you wanted to compensate for the average exhaust port by increasing the exhaust duration then be aware that this will bleed off compression and therefore torque lower in the RPM range, not good for a street engine.

 

Increasing exhaust duration will however make more upper RPM HP and stop the engine nosing over after peak HP. This is desirable for an engine intended to operate above about 6000 rpm.

 

Personally I have found that single pattern cams will make more torque and be more responsive in a street application, regardless of the head used. Once the owner wants to rev it up and make a bit more HP at the expense of mid range torque then by all means give it some more exhaust duration.

 

Short answer..... the 286 will be fine and really is hard to beat in any street Holden V8.

 

JMHO

Thanks Andrew....your explanation makes sense......this engine will be a mild streeter so no need to have peak Hp and torque towards the upper end of the rev range....

Im after good mid torque and i would like it to be a comfortable driver.

 

The comments above are from a man who know his 308's so I would listen to what he has said.

 

From my experiences, the Perfomer (dual plain) and Crane H286 hydraulic is probably the best set up for a good streeter 308. Not had a H286 with a VN headed engine but from all accounts I have heard, they also work well.

Thanks Gerry....Im listening with open ears.....and all the info I can find on the net and forums points to the same conclusion as Andrew just explained....so Im going to go with the H286 set up.

 

Thanks everyone

Al

[Redslur]

Flat top pistons, H286 cam, Performer manifold and a good exhaust and carby will get you around 300hp and flying along in a torry.

[slar]

Flat top pistons, H286 cam, Performer manifold and a good exhaust and carby will get you around 300hp and flying along in a torry.

Yep she's getting flat tops as we speak....square decked 15 thou..hot tanked..new bearings.....and got the crank linnished as it was in really good nick and still within spec....new flywheel and a complete rotating balance.

Ordered the new cam today H286 so Im committed now... got it for $285.00 which is pretty good......new stainless valves for the head...new pushrods...new crane lifters.

So heaps of money spent but I'm on my way lol.

 

Just have to sort the intake manifold now so any more advice on the pro's and cons of each brand would be great. Looking for good driveabilty with a strong mid range.

 

My old orange LH had a stock stroke VL 304 with Crane H286, VN type heads with a Harrop dual plane & 650HP Holley mechanical secondary carb. It ran off the shelf Pacemaker headers & dual 2 1/4" exhaust. It made 365hp at the flywheel & all fitted under an unmodified bonnet.

 

Was a very street friendly car to drive.

 

From what I've heard, the ports on the Redline Hi-winder don't match up too well on the heads & need some work, the Harrop was much better with little to no work needed, but then look at the price difference between the two.

 

Just my experience on this subject.

Nice....just what Im aiming for...thanks

[Redslur]

Torque Power or Harrop dual plain are the best options I reckon.  But both are quite dear. Worth it though in my opinion.  You will have a stout little engine by the sounds of things..

[Ice]

What carb you thinkin of runnin Al

[slar]

What carb you thinkin of runnin Al

 Hey Gene.....thats another good question......lots of info around about all sorts of carbies, some people swear by the Qjet...... so again feel free to suggest size and type combinations as I havent bought a carbie for it yet......I do have a Qjet here but not sure whether it will fit the VN carbie manifolds......never done this conversion before so I need all the advice I can get ....go for it lol