Roller Rockers

Post by **Coops** » Sun Feb 03, 2008 12:43 am

I'll mail v8 tuner and ask, but i think other members have had discount on any parts bought from Paul.

kokkolanpoika · Post by **kokkolanpoika** » Sun Feb 03, 2008 8:21 am

thev8kid wrote:I'll mail v8 tuner and ask, but i think other members have had discount on any parts bought from Paul.

Ok..

I just look at my note.. And i get very small discount 4% because i higgle.

Here is a "copy" of part my E-mail at Paul..

We only offer discounts on Crower Camshafts for V8 forum members as all our website prices are discounted to all. We have however reduced some prices as follows:

I get 4%/8,31£ discount when i higgle the prices. Original price 215,99 new total 207,68..

Is this normal price cut from them because i higgle, or is there some discount from V8 forum members also?? Thats i dont know..

But i understand that all their website prices are discounted to all of their customers.. And usually all prices inc some higgle "afford"

robert · Post by **robert** » Fri Feb 15, 2008 5:36 am

over here in Australia the cheapest way to have roller rockers is to start with P76 heads (better IMHO than rover) easy to machine to accept chev 1.6 rollers with modified ford guide plates. cost all up about $580 aus. (inluding machineing etc)
266 uk pounds roughly!!

see pic

mgbloke · Post by **mgbloke** » Mon Feb 25, 2008 4:59 pm

Well its all back together and running great. Rolling road showed 293hp @5800rpm with torque about the same as before, which on paper is only an 11hp increase.
Just to recap Ive changed from an RPI piper 285 cam , gone from an edelbrock performer to huffaker inlet and fitted roller rockers.
Strange thing is its like a completeley different car to drive, it now has serious attitude and I am very happy with the M238 cam.
Im now wondering if the exhaust is restricting things as the system is only 2 1/4 inch diameter.
Is it worth spending 600 odd quit for a new 2 1/2 inch custom system?

Looking forward to some track action!

CastleMGBV8 · Post by **CastleMGBV8** » Mon Feb 25, 2008 5:15 pm

Mark,

What type of manifold have you got, block huggers or RV8 style? Could be your primaries are a little on the small side, they need to be a little larger than the actual port size to avoid Exhaust gas reversion.

Kevin.

minorv8 · Post by **minorv8** » Wed Feb 27, 2008 7:04 am

I think it is easy to measure the exhaust back pressure. I would do that before spending cash. IMO even 2" dual exhaust will support a lot more HP that 300 odd before getting restrictive. Mufflers (or silencers whichever you prefer) are another issue. I have about the same hp with 1,5" primaries, 2" dual system with Jag X-type silencers.

mgbloke · Post by **mgbloke** » Wed Feb 27, 2008 6:43 pm

Kevin
Im using the Rv8 manifolds.
Have decided that its going to be too loud with a 2 1/2 inch system as I have only room for one silencer.
At present its about 98db @ 4500 rpm measured 500mm @ 45 degrees.
Minor V8
My system is 8 into 2 into 1 with the final internal size of only 2 1/8 inches! not ideal, but Ill have to live with it for now.

Mark

CastleMGBV8 · Post by **CastleMGBV8** » Wed Feb 27, 2008 7:22 pm

Mark

Where did you get the exhaust from? My RV8 single box system is 2 1/2" external diameter in stainless steel from MGB Hive was £399.00 may be a bit more now. Was reasonably quiet when I first had it but when i put some new plug leads on I cocked up and got it wrong, causing a couple of very loud backfires when I tried to start it.

I think the backfires must have compressed the packing as it's been louder ever since, I'm going to have a front box fitted which according to Mr. Vizard is good for power if fitted just after where the two down pipes meet.

Kevin.

mgbloke · Post by **mgbloke** » Thu Feb 28, 2008 10:55 am

Kevin
Mine is also from MGBhive! bought 8years ago at an MG show £350
It was a terrible fit so I had to do a lot of re working. I put an extra join just below the collector to make fitting easier.
I even port matched the flange area.
Its definateley 2 1/4 inch outside diameter.
Im booked in to the Siverstone GP circuit trackday on 17th March should be fun.
Mark

CastleMGBV8 · Post by **CastleMGBV8** » Fri Feb 29, 2008 5:23 pm

Mark,

I have heard that quality differs but the quality on mine is superb, a young friend of mine who welds to F1 standard said it was some the best welding he'd seen and the fit was perfect.

I'll check the primary size tomorrow if I remember.

Have fun at Silverstone.

Kevin.

desertrover · Post by **desertrover** » Sat Mar 01, 2008 12:18 am

If u have a standard engine, is there a diff in power and torque, when u use roller rockers instead of normal ones?

Do I feel a diff on my 4.6, stage 2 heads, Piper 270/108 cam, mallory unilite dizzy, headers with 3" straight thru exhaust, edelbrock 500, magnecore leads engine?

mgbloke · Post by **mgbloke** » Sat Mar 01, 2008 9:54 am

Desertrover
As I under stand it Roller rockers have less friction which must translate into a few hp.
A high lift cam puts more stress/side loading on the valve stems and tends to wear the guides more. This is the reason that I fitted them.
V8 tuner claims a 10bhp increase.
http://www.v8tuner.co.uk/product.php?id=533
I only saw a 11hp increase with higher spec cam included but thats not to say that more is there if I upgrade my exhaust and maybe heads.
Mark

HairbearTE · Post by **HairbearTE** » Sat Mar 01, 2008 7:14 pm

Don't forget there are two main types of roller rockers. Those that are bushed and fit in place of the originals on a regular shaft may gain a little power by reducing friction on the valve tip and thus reducing any side loadings on the valve but a more measurable gain can be had by using rocker systems that feature needle roller bearings instead of bushes. Even then the gains would work out very expensive in £/HP. For this reason roller rockers are a poor choice of mod on their own in an otherwise mild engine.

mgbloke · Post by **mgbloke** » Thu Mar 06, 2008 6:13 pm

Just checked the valve clearances again and have had to adjust most of them. Now I hope its all bedded in!
How often should I check them? after each trackday maybe.
Problem I have is it says adjust them Hot, but by the time Ive finished the engine has cooled quite a bit.
Car is used for road and track days.

Thanks
Mark