Heads refresh stage 5 heads
Discussion
Stage 5.
What’s the difference from stage 4 which I always believed to be the most blown heads you could get but now we have stage 5.
I presume these are shorter/ stronger valve guides so allowing a better flow into / out of heads
Having seen stage 4 heads which are ported about as far as you would dare to go without hitting water jacket. These valves also look the same size from here so I assume it’s the guides but then shortened guides have been available for years.
What sort of gains over stage 4 would you be hoping for or is it just a tidying up of what are basically stage 4 heads.
They look lovely
Some specs might help the boffins on here lol
What’s the difference from stage 4 which I always believed to be the most blown heads you could get but now we have stage 5.
I presume these are shorter/ stronger valve guides so allowing a better flow into / out of heads
Having seen stage 4 heads which are ported about as far as you would dare to go without hitting water jacket. These valves also look the same size from here so I assume it’s the guides but then shortened guides have been available for years.
What sort of gains over stage 4 would you be hoping for or is it just a tidying up of what are basically stage 4 heads.
They look lovely
Some specs might help the boffins on here lol
On this topic and not wanting to start another thread, where do the diminishing returns kick in with head work on these? I love the character of the engine in my 450 but would like to free up a bit more top end. It's about time for a new cam / top end refresh and was contemplating a bit of head work at the same time. Of course I will discuss with V8 developments etc, but it would be good to get some thoughts from the PH collective.
Adam205 said:
On this topic and not wanting to start another thread, where do the diminishing returns kick in with head work on these? I love the character of the engine in my 450 but would like to free up a bit more top end. It's about time for a new cam / top end refresh and was contemplating a bit of head work at the same time. Of course I will discuss with V8 developments etc, but it would be good to get some thoughts from the PH collective.
Head wise depends on what size valves you have , mine has had the new style valves fitted that allow more flow. Depending on how many miles you have done valve guides and some porting won’t go amiss. Talk to rob at v8 dev he will give you the options and honest opinion
Edited by hoofa on Tuesday 21st December 07:03
Probably best to speak to V8D about it, they are the experts.
I went with the Warriors on my 400 which are listed as a stage 2 on their site.
Combined with their 3 stage induction package and MC1 cam it made a big difference.
I would have gone Stealth cam but was told it couldn't be used without valve reliefs in the pistons.
I went with the Warriors on my 400 which are listed as a stage 2 on their site.
Combined with their 3 stage induction package and MC1 cam it made a big difference.
I would have gone Stealth cam but was told it couldn't be used without valve reliefs in the pistons.
Belle427 said:
Bet its fun trying to trim the gasket on those centre ports, they are close!
Buy Powers bigger manifold gaskets and you won’t have to trim anything. They have there very own pressing tool to enlarge the holes in standard gaskets
I presume V8D have a similar tool if they are porting heads.
Edited by Classic Chim on Tuesday 21st December 09:03
Zener said:
rev-erend said:
Is there a thermal coating in the chambers of those heads?
Certainly seems like it 
bizzarely I was using bigger inlet valves than these RV8 heads back in the day on a Ford X flow 44mm 
Yes but your Ford was missing 4 cylinders and therefore half an engine
Edited by Zener on Tuesday 21st December 14:50
Classic Chim said:
Belle427 said:
Bet its fun trying to trim the gasket on those centre ports, they are close!
Buy Powers bigger manifold gaskets and you won’t have to trim anything. They have there very own pressing tool to enlarge the holes in standard gaskets
Edited by Classic Chim on Tuesday 21st December 09:03
I can't find the gasket on Power's site, do you have a link? If not, I'll call them tomorrow. Thanks.
Edited by Boosted LS1 on Tuesday 21st December 16:32
hoofa said:
Zener said:
rev-erend said:
Is there a thermal coating in the chambers of those heads?
Certainly seems like it bizzarely I was using bigger inlet valves than these RV8 heads back in the day on a Ford X flow 44mm Yes but your Ford was missing 4 cylinders and therefore half an engine
Edited by Zener on Tuesday 21st December 14:50
just saying and all from less than 3.5 litres combined Boosted LS1 said:
That's really helpful, I've some TA heads on a turbo build and the gaskets definitely need trimming. I've seen some engines where the excess has been hammered over, into the ports.
I can't find the gasket on Power's site, do you have a link? If not, I'll call them tomorrow. Thanks.
Hmmm. Maybe they don’t do them anymore. Yes call Dom, trouble is I think he left the parts business to TVR Parts a bit which is a real pity to my mind but servicing keeps him very busy. I can't find the gasket on Power's site, do you have a link? If not, I'll call them tomorrow. Thanks.
Edited by Boosted LS1 on Tuesday 21st December 16:32
He stocked a lot of TVR stuff you don’t sell every week which I very much appreciated over the years and I’m sure he still does.
If you get standard gaskets his press will cut them to the size you see above or near as damn it. I presume he made it for 5.0 ported heads many years ago. The press was working around 3 years ago that’s all I can tell you.
If they then fit V8D heads exactly is another thing.
Do V8D have gasket options I wonder?
I have a standard inlet manifold gasket I had opened up so I could match the head ports to the gasket size exactly.
Just never seem to get on with finishing them. So much work it needs commitment lol but the gap between the ports are similar to the heads above so I’d say the closest thing to fit these heads you’ll get without adapting the gaskets yourself.
Zener said:
Well if it had the other 4 a good RV8 5.0 would be in trouble just saying and all from less than 3.5 litres combined
I had the privilege of being blown away at the drag strip by a Mk 1 Escort with a Harris engine I think? . I did like 13 seconds which is fast in a standard ish car while he did some mad 10.8 or lower just saying and all from less than 3.5 litres combined Gassing Station | Chimaera | Top of Page | What's New | My Stuff