45mm inlet and Plenum base inc 72 mm throttle pot.
Discussion
Yep no worries.
I might have a go tomorrow evening but I’ve sort of bottled it for now!
I’ve just concentrated on marking head ports and trial lining up inlet manifold. Defo need a camera app !
I need a valve spring compressor for the heads which I’ll borrow off Neal1980 as buying one seems pointless at this time.
As these heads have no rockers or shafts I’ll have to source these at a later date and inevitably I start thinking about YELLA TERRA roller rockers, the holy grail for rocker assembly on these style heads, can you run softer springs with these
What’s the pros,,, and cons.
If your going to do something you might as well do the best or what’s the point!
Might take longer but the rewards should be more than worth it.
325-340 hp could well be achievable with all these tweaks in place on the right engine.
Better stop talking and start digging,,,, good advice, wear masks as micro bits of Alloy fill the air!
I might have a go tomorrow evening but I’ve sort of bottled it for now!
I’ve just concentrated on marking head ports and trial lining up inlet manifold. Defo need a camera app !
I need a valve spring compressor for the heads which I’ll borrow off Neal1980 as buying one seems pointless at this time.
As these heads have no rockers or shafts I’ll have to source these at a later date and inevitably I start thinking about YELLA TERRA roller rockers, the holy grail for rocker assembly on these style heads, can you run softer springs with these
What’s the pros,,, and cons.
If your going to do something you might as well do the best or what’s the point!
Might take longer but the rewards should be more than worth it.
325-340 hp could well be achievable with all these tweaks in place on the right engine.
Better stop talking and start digging,,,, good advice, wear masks as micro bits of Alloy fill the air!
SILICONEKID 345HP 12.03 said:
What heads are they Alun ? Looks like I'm going to be in your fear view mirror
I need some forged bits if i’m going for your compression ratio 
I don’t think I’ll get near your figures Daz.
The heads are the ones pictured on page 10 of this thread, Peters heads he had lying about.
I can see myself being called to his place on many occasions to pay for it
I’ll be more than happy to oblige
They are the late efi heads and probably the same as my own heads as they came in around 1994 on RR stuff.
Has anyone got an exhaust manifold off the car they could measure the exhaust header size for me with an accompanying picture. If you happen to have an exhaust manifold gasket or even an old one, if you can offer that up to bolt positions so I can see the orientation and give me some idea of what size I can open ports too.
The exhaust ports on stage 4 heads are no bigger than the gasket which does allow me plenty of meat to remove but it’s all controlled by how big and matched I can make the exhaust headers. Seeing one of those with a gasket aligned will give me a good reference.
I’m hopimg they are somewhat larger than the ports so I can take the ports right out to gasket line.
Lots of thinking going on right now!
Peter and I are getting around 400 bhp with standard exhaust manifolds - well, we were until Peter went shiny. But I wonder if his noo toobs are any bigger?
Them and his Emerald added 15 bhp.
I cannot speak for the exhaust ports on Peter's stage 4 heads, but I am certain mine are absolutely bog standard Range Rover - my heads cost me £50 from a guy who builds Range Rover mud pluggers for off roading. My turbo, acting on the induction, is what gives me the BHP.
So I am not convinced that you will get any improvement by making the exhaust ports bigger.
i think it's your hard work on the inlet side that will help you make the gains.
Ok, I have put that up there - and would like those who know more than me to come along, educate me and help me understand why I am wrong. But only in terms of the TVR RV8 engine - I don't want a lesson in formula 1 thank you.
Them and his Emerald added 15 bhp.
I cannot speak for the exhaust ports on Peter's stage 4 heads, but I am certain mine are absolutely bog standard Range Rover - my heads cost me £50 from a guy who builds Range Rover mud pluggers for off roading. My turbo, acting on the induction, is what gives me the BHP.
So I am not convinced that you will get any improvement by making the exhaust ports bigger.
i think it's your hard work on the inlet side that will help you make the gains.
Ok, I have put that up there - and would like those who know more than me to come along, educate me and help me understand why I am wrong. But only in terms of the TVR RV8 engine - I don't want a lesson in formula 1 thank you.
N/A for maximum efficiency wants good pulse length that helps purging. It is well known that long header exhaust pipes such as ours promote hp.
Peters promote that even further as they flow into the pipes that replace the Y piece so flow better than a Y piece.
If the exhaust manifold ports are not well matched to the head ports so present an instant restriction to flow and create turbulence as the gases hit say a step it will reduce power.
You rely on forced air producing power so overcome these restrictions quite easily.
It’s true to say though and if you fancy an experiment we can prove it but bigger heads that flow in and out better with bigger valves will give you extra power with the same boost. Less restriction just lets it’s spin up faster and takes less power off the engine trying to force air in and out.
More efficient.
You’ll be well over 400..... probably above 420 hp with this lot on,,,,
Peters not going to like this
I just want to prove I can do it.
Not without taking very informed advice which is really the secret rather than me coming up with anything new.
If you noticed the difference in the size of the inlet ports on Saturday you’ll see much more air can travel through them.
Win win.
Contrary to what your saying Anthony and YES Peters are big bore manifolds
They present even less restriction at the ports so the results he got on the rolling road were what I was hoping and half expecting to see.
The turbulence caused when each bank of headers meet the Y piece is going to be considerable.
His car should be quieter up front If a bit louder out the back if my theory is correct.
Peters promote that even further as they flow into the pipes that replace the Y piece so flow better than a Y piece.
If the exhaust manifold ports are not well matched to the head ports so present an instant restriction to flow and create turbulence as the gases hit say a step it will reduce power.
You rely on forced air producing power so overcome these restrictions quite easily.
It’s true to say though and if you fancy an experiment we can prove it but bigger heads that flow in and out better with bigger valves will give you extra power with the same boost. Less restriction just lets it’s spin up faster and takes less power off the engine trying to force air in and out.
More efficient.
You’ll be well over 400..... probably above 420 hp with this lot on,,,,
Peters not going to like this
I just want to prove I can do it.
Not without taking very informed advice which is really the secret rather than me coming up with anything new.
If you noticed the difference in the size of the inlet ports on Saturday you’ll see much more air can travel through them.
Win win.
Contrary to what your saying Anthony and YES Peters are big bore manifolds
They present even less restriction at the ports so the results he got on the rolling road were what I was hoping and half expecting to see.
The turbulence caused when each bank of headers meet the Y piece is going to be considerable.
His car should be quieter up front If a bit louder out the back if my theory is correct.
Edited by Classic Chim on Wednesday 18th April 21:35
Edited by Classic Chim on Wednesday 18th April 21:42
While my minds on the subject
There’s a few reasons why someone like me finds this stuff and using tools and hand crafting rewarding.
It’s not so much how much power you have but how efficiently it can do the work.
I’m looking into single valve springs for instance as the less energy you use up operating the engine the more energy the engine can produce.
I find the idea of making it efficient at making the power and especially flowing the gases in and out as smoothly as possible something well worth doing.
Port matching is about as funky as you can get on a car,,,, that’s what I think
There’s a few reasons why someone like me finds this stuff and using tools and hand crafting rewarding.
It’s not so much how much power you have but how efficiently it can do the work.
I’m looking into single valve springs for instance as the less energy you use up operating the engine the more energy the engine can produce.
I find the idea of making it efficient at making the power and especially flowing the gases in and out as smoothly as possible something well worth doing.
Port matching is about as funky as you can get on a car,,,, that’s what I think
I also believe doing both exhaust and inlet increases the useable power curve
Extend it further up the revs towards limiter as often they just get really inefficient over 5200. Revs, that can make a lot of difference to overall performance and make the car a lot faster overall.
Even Mac mentioned the other week the better it all flows and just as importantly on a Turbo car it just adds lots of useable power let alone the two sets of numbers we go on about.
If you read into exhaust effects which are essentially the same as induction pulse or bounce as air gets sucked in then forced back out up towards Plenum, these forces on the exhaust side can help suck or push so allowing different can duration times, it gets complicated but the more purging you get from better flow rates the quicker you can fill or empty a cylinder so can reduce or lengthen these cam opening times to get best volumetric efficiency ( VE )
Talking about F1
The Gurney/Weslake V12 3.0 l engine of around 1968-72 that Weslake had built as a two cyl test engine with 4 valves per cyl. It was the first engine they’d ever tested on the bench that pumped out 158/160 Bhp per litre. BRM was persisting with a V16 and wouldn’t take on the design, Weslake showed Dan Gurney the test engine and it’s heads and the plans for a V12 based opon it and Gurney provided the money to build it. He won at Spa one year with this very engine. 450 Bhp from a 3.0 litre V12
Getting air In and out is always the key.
I thought it was thoughougly interesting
Extend it further up the revs towards limiter as often they just get really inefficient over 5200. Revs, that can make a lot of difference to overall performance and make the car a lot faster overall.
Even Mac mentioned the other week the better it all flows and just as importantly on a Turbo car it just adds lots of useable power let alone the two sets of numbers we go on about.
If you read into exhaust effects which are essentially the same as induction pulse or bounce as air gets sucked in then forced back out up towards Plenum, these forces on the exhaust side can help suck or push so allowing different can duration times, it gets complicated but the more purging you get from better flow rates the quicker you can fill or empty a cylinder so can reduce or lengthen these cam opening times to get best volumetric efficiency ( VE )
Talking about F1
The Gurney/Weslake V12 3.0 l engine of around 1968-72 that Weslake had built as a two cyl test engine with 4 valves per cyl. It was the first engine they’d ever tested on the bench that pumped out 158/160 Bhp per litre. BRM was persisting with a V16 and wouldn’t take on the design, Weslake showed Dan Gurney the test engine and it’s heads and the plans for a V12 based opon it and Gurney provided the money to build it. He won at Spa one year with this very engine. 450 Bhp from a 3.0 litre V12
Getting air In and out is always the key.
I thought it was thoughougly interesting
Yella Terra, took two minutes looking and reading.
Less side load on valve guides for one. Less friction another.
I’m going for shortened guides as they are a massive restriction if you just look into the ports,
So these Yella Terra look great value if they are reliable and long lasting. Can’t see any reason why not. It’s not just the Rv8 these things are made for.
There just damn fine looking things.
Better get earning some investement funds
Anyone need a gardener
Less side load on valve guides for one. Less friction another.
I’m going for shortened guides as they are a massive restriction if you just look into the ports,
So these Yella Terra look great value if they are reliable and long lasting. Can’t see any reason why not. It’s not just the Rv8 these things are made for.
There just damn fine looking things.
Better get earning some investement funds
Anyone need a gardener
spitfire4v8 said:
Ive never had any success using cartridge sanding sets .. ive always left mine as carbide finish. As long as the shape is smooth the difference in airflow is minimal. But for the extra bling factor if you want to sand them smooth then go for it.
Agreed, thrown them aside there s
t. If you can learn the art of consistent pressure and shaving uniformly I’m close to thinking you could do 90% with the carbide bits alone. Very satisfying when it’s all nice and smooth I’ll say that
Classic Chim said:
Yella Terra, took two minutes looking and reading.
Less side load on valve guides for one. Less friction another.
I’m going for shortened guides as they are a massive restriction if you just look into the ports,
So these Yella Terra look great value if they are reliable and long lasting. Can’t see any reason why not. It’s not just the Rv8 these things are made for.
There just damn fine looking things.
Better get earning some investement funds
Anyone need a gardener
Some porn for Alun Less side load on valve guides for one. Less friction another.
I’m going for shortened guides as they are a massive restriction if you just look into the ports,
So these Yella Terra look great value if they are reliable and long lasting. Can’t see any reason why not. It’s not just the Rv8 these things are made for.
There just damn fine looking things.
Better get earning some investement funds
Anyone need a gardener
Got To Do Something With My Time Waiting For Parts 
Sardonicus said:
Some porn for Alun
Got To Do Something With My Time Waiting For Parts
These look loads easier to set up once you’ve done the intitial set up work fitting them to the heads. Got To Do Something With My Time Waiting For Parts Are these your heads Simon. The sound of your car coming past was confirmation more than words can say, glorious.
All that air induction and thunder, I could almost feel those big valves opening
It’s going to look great too. Polished cyl heads anyone,,, not just the inside either
If it looks good it surely must go good
phazed said:
Alun. you could have borrowed my old exhaust manifolds for matching up.
Rushing about I didn’t even rack Simons brains,,, maybe collect them next week somehow. If I’m into this I should really come see all the cars at Snetterton and take notes
Just confirmed with QBee I’ll pop up to Snetterton
Classic Chim said:
Sardonicus said:
Some porn for Alun
Got To Do Something With My Time Waiting For Parts
These look loads easier to set up once you’ve done the intitial set up work fitting them to the heads. Got To Do Something With My Time Waiting For Parts Are these your heads Simon. The sound of your car coming past was confirmation more than words can say, glorious.
All that air induction and thunder, I could almost feel those big valves opening
It’s going to look great too. Polished cyl heads anyone,,, not just the inside either
If it looks good it surely must go good
agree with Rev-erend Kenne Bell are also fine RR's if your going the Yella Terra route start looking for new old stock rocker shafts mine are old stock genuine Range Rover items no point putting new rocker arms on old shafts IMO (unless you want to fk-em up of course) outrigger posts are available and just need a minor fettle to fit,, those spacers between the rocker arms I had made just because I could they are not essential however but why not? .......... and even less needed for moderate cam grinds or more sedate RPM use , I intended to use regular high RPM so it was a no brainer for the outlay and trouble Edited by Sardonicus on Thursday 19th April 15:48
Thanks Rev, I’ll look out for them.
I’ll start looking for rocker shafts Simon.
Just had a few hours at Powers and what fun I’ve had.
Used Dom’s blasting machine to proper clean my inlet manifold, borrowed/ robbed a 45 mm manifold for dimensions and something to work too.
I’ve got to go over and paint the walls to pay for all this brain stealing I’m doing
Anyway Jason set me up and here’s my porting that wasn’t finished but I thought I’d see what it turns out like with some proper blasting /cleaning.
I’ll do the heads next week when I’ve got valves out. Wait til you see those babies.
Never say never I say
I’ll start looking for rocker shafts Simon.
Just had a few hours at Powers and what fun I’ve had.
Used Dom’s blasting machine to proper clean my inlet manifold, borrowed/ robbed a 45 mm manifold for dimensions and something to work too.
I’ve got to go over and paint the walls to pay for all this brain stealing I’m doing
Anyway Jason set me up and here’s my porting that wasn’t finished but I thought I’d see what it turns out like with some proper blasting /cleaning.
I’ll do the heads next week when I’ve got valves out. Wait til you see those babies.
Never say never I say
Edited by Classic Chim on Thursday 19th April 17:48
Sardonicus said:
Yes Alun thats my engine, the adjustable bit is useful for me because of the mechanical/solid cam no faffing with adjustable push-rods agree with Rev-erend Kenne Bell are also fine RR's if your going the Yella Terra route start looking for new old stock rocker shafts mine are old stock genuine Range Rover items no point putting new rocker arms on old shafts IMO (unless you want to fk-em up of course) outrigger posts are available and just need a minor fettle to fit,, those spacers between the rocker arms I had made just because I could they are not essential however but why not? .......... and even less needed for moderate cam grinds or more sedate RPM use , I intended to use regular high RPM so it was a no brainer for the outlay and trouble
I get all that about the spacers and outrigger posts as I talked to Peter earlier.
Those spacers are bang on
Desperate for a valve spring compressor now as I can’t wait to clean the heads up so I can make some marks that will need working I might rent workshop space and his tooling at Doms to do at least one head there so I don’t fk it up.
Infact the inlet manifold I’ve borrowed was ported by one of the guys who’s been there like 20 years on and off, he did it all those years ago.
Also I looked at the one they have cut down into the runners until it’s broken through. Gives me a clear idea of which runners to be very careful with.
It’s worth some money I know that
agree with Rev-erend Kenne Bell are also fine RR's if your going the Yella Terra route start looking for new old stock rocker shafts mine are old stock genuine Range Rover items no point putting new rocker arms on old shafts IMO (unless you want to fk-em up of course) outrigger posts are available and just need a minor fettle to fit,, those spacers between the rocker arms I had made just because I could they are not essential however but why not? .......... and even less needed for moderate cam grinds or more sedate RPM use , I intended to use regular high RPM so it was a no brainer for the outlay and trouble I get all that about the spacers and outrigger posts as I talked to Peter earlier.
Those spacers are bang on
Desperate for a valve spring compressor now as I can’t wait to clean the heads up so I can make some marks that will need working
I might rent workshop space and his tooling at Doms to do at least one head there so I don’t fk it up. Infact the inlet manifold I’ve borrowed was ported by one of the guys who’s been there like 20 years on and off, he did it all those years ago.
Also I looked at the one they have cut down into the runners until it’s broken through. Gives me a clear idea of which runners to be very careful with.
It’s worth some money I know that
Edited by Sardonicus on Thursday 19th April 15:48
Standard inlet manifold ports
Against nearly completed ports matched to the largest gaskets that are also chopped out by about 1.5 mm so as big as they get
I’ll be removing my heart shaped groves for the more accepted flatttened option too.
Proper into this now I am, what a great hobby, just got to get off my arse and start grafting. Porting is proper mental and physical graft. Hours and hours of it but worth every second when it starts to look good.
Mega.
Against nearly completed ports matched to the largest gaskets that are also chopped out by about 1.5 mm so as big as they get
I’ll be removing my heart shaped groves for the more accepted flatttened option too.
Proper into this now I am, what a great hobby, just got to get off my arse and start grafting. Porting is proper mental and physical graft. Hours and hours of it but worth every second when it starts to look good.
Mega.
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