45mm inlet and Plenum base inc 72 mm throttle pot.
Discussion
QBee said:
Classic Chim said:
Identification marks
Suggests 1997
Or it means what it says and was made in 1597. I sometimes think the Rover V8 predates the industrial revolution by a couple of hundred years......bit like Yorkshiremen. Suggests 1997
QBee said:
Or it means what it says and was made in 1597. I sometimes think the Rover V8 predates the industrial revolution by a couple of hundred years......bit like Yorkshiremen.
What is it with you and Yorkshiremen Nah our engines are awesome if a bit restricted but I’m about to deal with that
Classic Chim said:
What is it with you and Yorkshiremen
Nah our engines are awesome if a bit restricted but I’m about to deal with that
I used to be fine with Yorkshiremen........then I bought a used car off one. Nah our engines are awesome if a bit restricted but I’m about to deal with that
I like all Yorkshiremen that I have come across on PH and Faceache. Especially Jacko and Steve Edwards. Salt of the earth and all round good guys. And the SYTVRCC lot are good guys too.
It’s just the lying two-faced s
tbag ahole from Doncaster who sold me my Saab who has coloured my judgement regarding the inbabitants of God’s Own County. QBee said:
I used to be fine with Yorkshiremen........then I bought a used car off one.
I like all Yorkshiremen that I have come across on PH and Faceache. Especially Jacko and Steve Edwards. Salt of the earth and all round good guys. And the SYTVRCC lot are good guys too.
It’s just the lying two-faced stbag ahole from Doncaster who sold me my Saab who has coloured my judgement regarding the inbabitants of God’s Own County.
The twunt must have moved there! I like all Yorkshiremen that I have come across on PH and Faceache. Especially Jacko and Steve Edwards. Salt of the earth and all round good guys. And the SYTVRCC lot are good guys too.
It’s just the lying two-faced s
tbag ahole from Doncaster who sold me my Saab who has coloured my judgement regarding the inbabitants of God’s Own County. 
Will do 
Yep that’s what I thought.
So far I’ve lined up a gasket and ported the inlet manifold to the gasket but I can’t help but feel the tolerances in the bolt connecting holes is so big lining the manifold up to heads accurately after porting them will be a guess so I’m thinking of drilling some small holes in indiscriminate places that won’t effect gasket seal that goes through manifold/ gasket and a couple of mm into the heads, one st each end of both heads.
So when you bolt the heads to a car you can line up each side with the small holes in the heads and manifold and slowly nip down manifold on both sides You’ll be able to locate the gasket in exactly the correct position at the same time.
Years ago an old mechanic knew I had an interest in this porting lark and told me stories of his Bentley days
Drilling and putting a small dowl in place so you could line them and the exhausts up after they too had port matched the manifolds.
Trouble is I don’t think the tvr manifold will work with dowels but something similar has to be the order or it’s a waste of 60 hrs of my time if they don’t line up perfect every time
Eta the drilled holes and dowel trick might just work on the exhaust manifolds though.
I’ve been pondering this for awhile then remembered that old chap. Great bloke who re floored my old Jag many years ago. This bloke made floor pans that were like the original only better from sheets of tin
Yep that’s what I thought. So far I’ve lined up a gasket and ported the inlet manifold to the gasket but I can’t help but feel the tolerances in the bolt connecting holes is so big lining the manifold up to heads accurately after porting them will be a guess so I’m thinking of drilling some small holes in indiscriminate places that won’t effect gasket seal that goes through manifold/ gasket and a couple of mm into the heads, one st each end of both heads.
So when you bolt the heads to a car you can line up each side with the small holes in the heads and manifold and slowly nip down manifold on both sides You’ll be able to locate the gasket in exactly the correct position at the same time.
Years ago an old mechanic knew I had an interest in this porting lark and told me stories of his Bentley days
Drilling and putting a small dowl in place so you could line them and the exhausts up after they too had port matched the manifolds.
Trouble is I don’t think the tvr manifold will work with dowels but something similar has to be the order or it’s a waste of 60 hrs of my time if they don’t line up perfect every time
Edited by Classic Chim on Sunday 22 April 00:10
Eta the drilled holes and dowel trick might just work on the exhaust manifolds though.
I’ve been pondering this for awhile then remembered that old chap. Great bloke who re floored my old Jag many years ago. This bloke made floor pans that were like the original only better from sheets of tin
Edited by Classic Chim on Sunday 22 April 00:15
Classic Chim said:
Will do Yep that’s what I thought.
So far I’ve lined up a gasket and ported the inlet manifold to the gasket but I can’t help but feel the tolerances in the bolt connecting holes is so big lining the manifold up to heads accurately after porting them will be a guess so I’m thinking of drilling some small holes in indiscriminate places that won’t effect gasket seal that goes through manifold/ gasket and a couple of mm into the heads, one st each end of both heads.
So when you bolt the heads to a car you can line up each side with the small holes in the heads and manifold. You’ll be able to locate the gasket in exactly the correct position at the same time.
Years ago an old mechanic knew I had an interest in this porting lark and told me stories of his Bentley days
Drilling and putting a small dowl in place so you could line them and the exhausts up after they too had port matched the manifolds.
Trouble is I don’t think the tvr manifold will work with dowels but something similar has to be the order or it’s a waste of 60 hrs of my time if they don’t line up perfect every time
The doweled intake method is what I used on my fast Ford X Flow back in the 90's however no good for a V config, I indexed my inlet manifold on the RV8 to the heads with a fine tyre pen marking gasket to valley/block and both heads Yep that’s what I thought. So far I’ve lined up a gasket and ported the inlet manifold to the gasket but I can’t help but feel the tolerances in the bolt connecting holes is so big lining the manifold up to heads accurately after porting them will be a guess so I’m thinking of drilling some small holes in indiscriminate places that won’t effect gasket seal that goes through manifold/ gasket and a couple of mm into the heads, one st each end of both heads.
So when you bolt the heads to a car you can line up each side with the small holes in the heads and manifold. You’ll be able to locate the gasket in exactly the correct position at the same time.
Years ago an old mechanic knew I had an interest in this porting lark and told me stories of his Bentley days
Drilling and putting a small dowl in place so you could line them and the exhausts up after they too had port matched the manifolds.
Trouble is I don’t think the tvr manifold will work with dowels but something similar has to be the order or it’s a waste of 60 hrs of my time if they don’t line up perfect every time
your right quite a lot of movement and you need to keep an eye on your ref marks as the intake pulls down into the valley Sardonicus said:
The doweled intake method is what I used on my fast Ford X Flow back in the 90's however no good for a V config, I indexed my inlet manifold on the RV8 to the heads with a fine tyre pen marking gasket to valley/block and both heads your right quite a lot of movement and you need to keep an eye on your ref marks as the intake pulls down into the valley
It’s all very well just lining them up on a perfect centre but as you say will they bolt down like that when on the block. Heads might not even fit square for all I know. I’ll need a big set square to check them when putting it together,,, mad scientist comes to mind but if you ignore this it’s all a bit of a waste of time. your right quite a lot of movement and you need to keep an eye on your ref marks as the intake pulls down into the valley I did think some marker pen would do the job and you’ll see any changes when you tighten them down. It’s the gasket I’m also trying to get spot on but the pen idea would work there too.
The Valley gasket is fairly rigid after all and won’t de form.
I just like the idea of a permanent solution and easy reference points.
At a rough guess something like this
The head has a raised platform for the manifold to sit on, I’m sure I can drill through the manifold and into the head a few mm for my reference marks.
It will go through the gasket too so all three matched for position in one go.
Ok I’m coming to a decision, tell me if it needs work
I port heads to gasket line. Bolt head and gasket to manifold. Use camera to check for steps And fine tune porting to match, repeat this process until it all lines up every time then finally drill my small pilot holes for future reference
Repeat on other side of manifold and 2nd head.
Hope it all lines up when on an engine!
Good or bad idea ?
The head has a raised platform for the manifold to sit on, I’m sure I can drill through the manifold and into the head a few mm for my reference marks.
It will go through the gasket too so all three matched for position in one go.
Ok I’m coming to a decision, tell me if it needs work
I port heads to gasket line. Bolt head and gasket to manifold. Use camera to check for steps And fine tune porting to match, repeat this process until it all lines up every time then finally drill my small pilot holes for future reference
Repeat on other side of manifold and 2nd head.
Hope it all lines up when on an engine!
Good or bad idea ?
What valve sizes do you have?
Intermediate usually means Inlet at 41.4mm / 1.63" but those don't come as standard on any rover factory heads,
Stock rover sizes are;
Standard 39.83mm
Small 38mm (Rover P5 only IIRC)
Aftermarkets are;
Intermediate 41.4mm (limit of what will fit on a standard seat)
TVR Big Valve 43mm
44.4mm
46.8mm
You're starting from the wrong end, bowl work first.
The graph below shows head flow at 28" for a port match in red and in blue, removing the lip in the aluminium at the valve throat to seat insert and a quick blend in the same area. Both for a standard ERC0216 head with standard 39.83mm inlet valve. HRC2210's are nigh on identical ( maybe 1-2cfm flow advantage at a couple of lift points stock, and no advantage when ported)
Intermediate usually means Inlet at 41.4mm / 1.63" but those don't come as standard on any rover factory heads,
Stock rover sizes are;
Standard 39.83mm
Small 38mm (Rover P5 only IIRC)
Aftermarkets are;
Intermediate 41.4mm (limit of what will fit on a standard seat)
TVR Big Valve 43mm
44.4mm
46.8mm
You're starting from the wrong end, bowl work first.
The graph below shows head flow at 28" for a port match in red and in blue, removing the lip in the aluminium at the valve throat to seat insert and a quick blend in the same area. Both for a standard ERC0216 head with standard 39.83mm inlet valve. HRC2210's are nigh on identical ( maybe 1-2cfm flow advantage at a couple of lift points stock, and no advantage when ported)
Edited by SuperApeInGoodShape on Sunday 22 April 10:52
SuperApeInGoodShape said:
What valve sizes do you have?
Intermediate usually means Inlet at 41.4mm / 1.63" but those don't come as standard on any rover factory heads,
Stock rover sizes are;
Standard 39.83mm
Small 38mm (Rover P5 only IIRC)
Aftermarkets are;
Intermediate 41.4mm (limit of what will fit on a standard seat)
TVR Big Valve 43mm
44.4mm
46.8mm
You're starting from the wrong end, bowl work first.
The graph below shows head flow at 28" for a port match in red and in blue, removing the lip in the aluminium at the valve throat to seat insert and a quick blend in the same area. Both for a standard ERC0216 head with standard 39.83mm inlet valve. HRC2210's are nigh on identical ( maybe 1-2cfm flow advantage at a couple of lift points stock, and no advantage when ported)
Thanks for your post. Intermediate usually means Inlet at 41.4mm / 1.63" but those don't come as standard on any rover factory heads,
Stock rover sizes are;
Standard 39.83mm
Small 38mm (Rover P5 only IIRC)
Aftermarkets are;
Intermediate 41.4mm (limit of what will fit on a standard seat)
TVR Big Valve 43mm
44.4mm
46.8mm
You're starting from the wrong end, bowl work first.
The graph below shows head flow at 28" for a port match in red and in blue, removing the lip in the aluminium at the valve throat to seat insert and a quick blend in the same area. Both for a standard ERC0216 head with standard 39.83mm inlet valve. HRC2210's are nigh on identical ( maybe 1-2cfm flow advantage at a couple of lift points stock, and no advantage when ported)
Edited by SuperApeInGoodShape on Sunday 22 April 10:52
I haven’t actually started on the heads.
I’m mainly concentrating on roof porting for exhaust ports and matching to inlet.
Yes to both points re throat porting and seat area as there are some serious steps in that area.
These are the standard 39.8 mm valves and the seats look very good but I havnt decided on valve size yet so no point touching that area until I decide. Be easier to dress up without seats there for a start so I’m thinking big as I can get really.
Have you had your current heads off?
It's just that it's impossible to make 300bhp on stock unported Rover heads, so i think either you actually have already ported heads on the car, or you don't have 300bhp as is. (Unless i've missed you saying it forced induction somewhere )
Really 260hp would be pushing it for a totally unported head.
It's just that it's impossible to make 300bhp on stock unported Rover heads, so i think either you actually have already ported heads on the car, or you don't have 300bhp as is. (Unless i've missed you saying it forced induction somewhere )
Really 260hp would be pushing it for a totally unported head.
Edited by SuperApeInGoodShape on Sunday 22 April 17:01
Engine has been rebuilt but with standard heads and exactly the same as the ones I’ve pictured here other than steel rockers and double valve springs, 5 years +
4.6 engine with main cat in place. You can add 5-10 hp straight away by removing Cat.
My long term plan is to prove these heads and manifold on my car on a dyno while I then rebuild/port my own heads to similar spec incl inlet manifold then sell them as a matched set to pay off my friends
If I can show what they can do hopefully someone will want them
These heads the ports overall are very impressive if small.
I was told the later cast ones are good and I’d fully agree.
There’s very little room around the throat area and some of that needs to support the seat.
Looks to me like biggest valves are the only real solution and no amount of burr grinding can change that fact.
I’d really like to look at Tvr 5.0 heads but also a Boggo 4.0 head off an earlier engine to see if these castings are indeed better or not. The port shape etc
Edited by Classic Chim on Sunday 22 April 18:07
Ahh yes 254 hp seems about right for stock heads, sorry not sure where i got 300hp from.
If you want to achieve 320bhp to 340bhp range you will need at least the 41.4mm valve. 300hp+ from the stock valve (39.83mm) is only just doable with a very, very well developed head that is not achievable for a home porter.
To give you some idea of headflow needed for power, the superflow manual gives an equation that works out to being able to produce 2.05 horsepower for every CFM @28" (this is a fully optismised engine with everything holistically developed), for a more normal rv8 build 1.7 to 1.8 is ballpark.
I've found that it's difficult to achieve more than 87 cfm per Inch squared of valve area on the stock castings (merlins & TA perf can do more) so that gives you an upper limit of what is achieveable with each inlet valve size that is available.
If you want to achieve 320bhp to 340bhp range you will need at least the 41.4mm valve. 300hp+ from the stock valve (39.83mm) is only just doable with a very, very well developed head that is not achievable for a home porter.
To give you some idea of headflow needed for power, the superflow manual gives an equation that works out to being able to produce 2.05 horsepower for every CFM @28" (this is a fully optismised engine with everything holistically developed), for a more normal rv8 build 1.7 to 1.8 is ballpark.
I've found that it's difficult to achieve more than 87 cfm per Inch squared of valve area on the stock castings (merlins & TA perf can do more) so that gives you an upper limit of what is achieveable with each inlet valve size that is available.
Edited by SuperApeInGoodShape on Sunday 22 April 18:10
The graph is at the wheels so adding a rather generous 15/17% road train loss and if you also add the known quantity of a Clive Y piece at around 7/10 hp I can easily make it add up to 300 but thats just games
I have used a Clive Y and my car was faster by over 1/2 second on the drag strip.
That’s interesting math on what can be gained. I thought I’d have more to do on these heads but it’s really just tickling them mostly. Shortened guides look to be a must going by the little space available around them.
Steep learning curve and I’ve only just got the heads so I’ll be taking my time and learning off a master or two hopefully.
Without that knowledge I wouldn’t touch these heads as the ports look good to me and as your graph earlier shows very little will be gained unless the valve and throat area is shaped.
I was hoping to use original seats but the bigger the valve the more I can smooth the steps out.
On my own car I’d possibly risk using the guides which are like new and just shortening them but it’s false economy and just a worry factor so if new big valves are going in then billet guides on the list.
I better start earning some money I know that.
Great fun though as I know a RR head better then I thought I would already and I’ve only had them a week.
I have used a Clive Y and my car was faster by over 1/2 second on the drag strip.
That’s interesting math on what can be gained. I thought I’d have more to do on these heads but it’s really just tickling them mostly. Shortened guides look to be a must going by the little space available around them.
Steep learning curve and I’ve only just got the heads so I’ll be taking my time and learning off a master or two hopefully.
Without that knowledge I wouldn’t touch these heads as the ports look good to me and as your graph earlier shows very little will be gained unless the valve and throat area is shaped.
I was hoping to use original seats but the bigger the valve the more I can smooth the steps out.
On my own car I’d possibly risk using the guides which are like new and just shortening them but it’s false economy and just a worry factor so if new big valves are going in then billet guides on the list.
I better start earning some money I know that.
Great fun though as I know a RR head better then I thought I would already and I’ve only had them a week.
Porting is very non-intutive, air flow is simply not doing what you think it should be doing. Often grinding in a place where you are positive will increase flow will actually kill it.
Also every change is interdependent on everything else you do in the port, seat and chamber. It's often also very subtle, where removing as little as 0.5mm off the wall in the right (or wrong) place can have a big effect. I've seen bulleted valves kill flow over the big fat standard guides in some ports etc.
The main gains are not to be found where people think, i.e it's not at the port face on the heads, and it's not the 38mm round section on the manifold. It's easy to end up with an inlet tract that ends up going big-small-big-small-big with too sudden a port taper and end up killing power potential. Pay attention to your cross sectional areas throughout the total run from inlet trumpet to valve.
I would double check the at the wheels thing, it's a simply astonishing figure if they really are bone stock rover heads.
Also every change is interdependent on everything else you do in the port, seat and chamber. It's often also very subtle, where removing as little as 0.5mm off the wall in the right (or wrong) place can have a big effect. I've seen bulleted valves kill flow over the big fat standard guides in some ports etc.
The main gains are not to be found where people think, i.e it's not at the port face on the heads, and it's not the 38mm round section on the manifold. It's easy to end up with an inlet tract that ends up going big-small-big-small-big with too sudden a port taper and end up killing power potential. Pay attention to your cross sectional areas throughout the total run from inlet trumpet to valve.
I would double check the at the wheels thing, it's a simply astonishing figure if they really are bone stock rover heads.
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