Roller Cam

[debaron]

Get in! - Roller Cam arrived from the US today. Been hunting around for a while - TA Performance do them but when it actually came to getting a quote and shipping, The Wedge Shop came through on top.

Figures are

Lift - 544
Dur - 318
Dur@50 - 246
LCA - 110

Has the relief already machined for retaining plate.

Cost landed was around $1300. Hoping that it's an investment that will pay off in terms of power and longevity. Will be running in 4.8L with forged pistons and stage 3 intake, megasquirt etc



[url]

|https://thumbsnap.com/ZbH1wmz5[/url]

[Sardonicus]

debaron said:

Get in! - Roller Cam arrived from the US today. Been hunting around for a while - TA Performance do them but when it actually came to getting a quote and shipping, The Wedge Shop came through on top.

Figures are

Lift - 544
Dur - 318
Dur@50 - 246
LCA - 110

Has the relief already machined for retaining plate.

Cost landed was around $1300. Hoping that it's an investment that will pay off in terms of power and longevity. Will be running in 4.8L with forged pistons and stage 3 intake, megasquirt etc



[url]

|https://thumbsnap.com/ZbH1wmz5[/url]

Hats off be nice to hear how you get on but I know it will be good roller cams are the bks IMO

[phazed 11.83]

Very, very nice.

Looking forward to seeing final figures when you have it up and running.

Will you be running the 72 mm plenum?

[SILICONEKID 345HP 12.03]

Will it give more power ?

Why arnt they manufactured in the UK ?

[debaron]

SILICONEKID 345HP 12.03 said:

Will it give more power ?

Why arnt they manufactured in the UK ?

Good questions Daz

Yes it should give more power because the valve is 'more' off it's seat quicker and for longer compared to flat tappet. Roller Cams can run much steeper 'up ramp' compared to flat tappet - flat tappets would just dig in to the side of a roller lobe but the wheel on the roller lifter can easily handle it.

I guess because there are only a couple custom cam grinders in the UK for what is a comparatively rare engine these days, and being that a flat tappet cam is around a quarter of the cost of a roller for this engine - there just isn't the demand...

Plus it means different valve springs, roller rockers (£££), custom pushrods (££) vernier timing etc.. it's not just a straight swap.

[debaron]

phazed 11.83 said:

Very, very nice.

Looking forward to seeing final figures when you have it up and running.

Will you be running the 72 mm plenum?

Thanks Peter - Only have the standard plenum currently - do you think the 72 would pay dividends?

At what sort of power does the standard become restrictive?

[phazed 11.83]

Now there is a question .
A 72 mm plenum Will definitely help with the breathing and improve hp

What general specification are you going for and what size engine?

[carsy]

Really pleased someone has taken the plunge with this set up. Really look forward to the results.

What have you gone for; low down torque or an 8k rpm racer. Im assuming the Wedge shop had a few offerings.

[rev-erend]

That is one wild cam .. but hopefully the roller cam profile will help a lot with the low down torque to compensate.

Wish I had gone to one of those for my engine instead of the M256 but I can always upgrade later.

Seems a shame the Wedge shop does not have some off the shelf cams and profiles to choose from.

How were they to deal with, did you have to specify all cam details or just describe what you wanted from it.

Edited by rev-erend on Friday 2nd June 15:17

[SILICONEKID 345HP 12.03]

What would it cost for all the parts needed to change to a roller cam .

Can you give me a list of parts ?

[debaron]

SILICONEKID 345HP 12.03 said:

What would it cost for all the parts needed to change to a roller cam .

Can you give me a list of parts ?

Sure Daz

You'll need:

http://www.v8tuner.co.uk/product.php?id=533 - Roller Rockers

http://www.v8tuner.co.uk/product.php?id=422 - Pushrods that can be cut down - there may be some chevy/ford ones that already work without cutting

http://www.v8tuner.co.uk/product.php?id=680 - Vernier timing chain to get cam spot on

http://www.johnealesroverv8.co.uk/9.html - not essential but a good investment

http://www.thewedgeshopstore.com/products/Roller-C... - Plus the cam of course

[Steve_D]

What revs will that take?

My understanding is that the extra mass of the roller lifter brings valve bounce in earlier limiting the revs.
I have a Chevy engine in another car and fitted roller lifters to that and was advised to fit a 'Rev kit' which is basically an extra set of springs that sit on top of the lifters.


Steve

[debaron]

rev-erend said:

That is one wild cam .. but hopefully the roller cam profile will help a lot with the low down torque to compensate.

Wish I had gone to one of those for my engine instead of the M256 but I can always upgrade later.

Seems a shame the Wedge shop does not have some off the shelf cams and profiles to choose from.

How were they to deal with, did you have to specify all cam details or just describe what you wanted from it.

Edited by rev-erend on Friday 2nd June 15:17

So I mentioned to Woody how the engine was setup and that I was running a Crower 50234 and was looking for mid to high end tractability like the Crower does - but with maybe figure of around 350BHP and he came back with two specs:

Cam 1

Lift 544
Dur 318
Dur@50 - 246
LC - 108 - 110

Cam 2

Lift 542
Dur 310/318
Dur @ 50 - 240/246
LC 108-110

"Cam 1 will make more torque - cam 2 will rev quicker"


He was quick to reply and seems to know his stuff. Very knowledgeable.

[Sardonicus]

Steve_D said:

What revs will that take?

My understanding is that the extra mass of the roller lifter brings valve bounce in earlier limiting the revs.
I have a Chevy engine in another car and fitted roller lifters to that and was advised to fit a 'Rev kit' which is basically an extra set of springs that sit on top of the lifters.


Steve

Swings and roundabouts Steve now look at the roller cam profile look at how much easier the spring has of controlling things nice egg shaped ramp and toe transition compared to this for example conventional

[Steve_D]

Sardonicus said:

Steve_D said:

What revs will that take?

My understanding is that the extra mass of the roller lifter brings valve bounce in earlier limiting the revs.
I have a Chevy engine in another car and fitted roller lifters to that and was advised to fit a 'Rev kit' which is basically an extra set of springs that sit on top of the lifters.


Steve

Swings and roundabouts Steve now look at the roller cam profile look at how much easier the spring has of controlling things nice egg shaped ramp and toe transition compared to this for example conventional

Yes the profile is much nicer and will help a lot but the problem is that the lifter is now quite a bit heavier. Once it has started moving upwards its additional mass/inertia makes it want to continue upward rather than coming back down with the cam. This could be controlled with stronger valve springs but then you need to start looking at stronger rockers etc etc.
The rev kit helps the existing valve springs.

There is an additional benefit claimed for the kit.
A valve train related failure is most likely to be rocker, valve spring, dropped valve etc. In this case a standard lifter and pushrod normally get ejected and end up laying in the valley. If this happens with a roller lifter it comes out of its housing and turns its partner through 90 degrees and the roller on that lifter digs in and wrecks the cam and possibly the block as well.

Steve

[Sardonicus]

Steve_D said:

Sardonicus said:

Steve_D said:

What revs will that take?

My understanding is that the extra mass of the roller lifter brings valve bounce in earlier limiting the revs.
I have a Chevy engine in another car and fitted roller lifters to that and was advised to fit a 'Rev kit' which is basically an extra set of springs that sit on top of the lifters.


Steve

Swings and roundabouts Steve now look at the roller cam profile look at how much easier the spring has of controlling things nice egg shaped ramp and toe transition compared to this for example conventional

Yes the profile is much nicer and will help a lot but the problem is that the lifter is now quite a bit heavier. Once it has started moving upwards its additional mass/inertia makes it want to continue upward rather than coming back down with the cam. This could be controlled with stronger valve springs but then you need to start looking at stronger rockers etc etc.
The rev kit helps the existing valve springs.

There is an additional benefit claimed for the kit.
A valve train related failure is most likely to be rocker, valve spring, dropped valve etc. In this case a standard lifter and pushrod normally get ejected and end up laying in the valley. If this happens with a roller lifter it comes out of its housing and turns its partner through 90 degrees and the roller on that lifter digs in and wrecks the cam and possibly the block as well.

Steve

I appreciate the failure part Steve (thats a known with roller lifters and those strap's) but worries of valve control bounce etc at high RPM I just dont think your average Tivver builds or as built a RV8 to rev to those dizzy heights to become an issue, you can probably count those that do on one and that regularly exceed 6.5k even if they say they do bragging rights and all that , I dont even believe that the double springs are necessary on many of the softer profiles owners run with either i.e MC1 , 218 etc

Edited by Sardonicus on Saturday 3rd June 18:06

[Boosted LS1]

I was going to attempt something like this using buick v6 profiles but ground up on a v8 blank. The solution I was going to use would be a rev plate either welded or bolted into the V. It seems like a decent mod as the top end gets to act completely normally whilst the rev plate takes care of the lifters.

I never progressed beyond the parts stage as I discovered turbochargers :-). I was also worried about rovers having small journal cams that only allowed small lobes.

[Matthew Poxon]

Very much looking forward to hearing how you get on. Many people have spoken about roller cams but no-one to my knowledge has one working in a RV8 TVR yet.

[debaron]

Boosted LS1 said:

I was going to attempt something like this using buick v6 profiles but ground up on a v8 blank. The solution I was going to use would be a rev plate either welded or bolted into the V. It seems like a decent mod as the top end gets to act completely normally whilst the rev plate takes care of the lifters.

Hi Boosted - can you elaborate? Is it something I will likely need on a 6K revving 350BHP ish motor?

[QBee]

Going back to Phazed's earlier point about the 72mm plenum, getting more air in seems to me to be the biggest problem area restricting one from making serious BHP out of the RV8 engine.
Over the last 4 years i have modified my car, with a bigger engine, bigger heads, wilder cam, bigger plenum, bigger injectors, finally to realise that without starting again on the heads etc i was never going to get anywhere on getting serious amounts more power.
So do look at the rest of the spec of your engine and let us advise.