wedge engine 821/697 the ultimate evolution.

[MRN I J]

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Hermes ones were exactly that, they used the original head type with the really bad inlet ports, one thing I found whist buying every Renault engine part that would fit my car was the last non crossflow heads had beautiful small round individual inlet ports, ideal for porting by someone who knows how to / uses a flowbench for guidance rather than accepting the flowbench as the be-all, end-all.

    Hi MRN I J or Valerio , do you have any flowbench results of any crossflow or wedge in its stock form? Or Modified? there seems to be no documentation in this area.
dakazman
[/quote]

Quite a few years ago I had a lot of airflow work carried out (in 1995 or there abouts) however I'm not sure that it was ever carried out properly, I never gave my head man from 2009 on to airflow test as I have spent the last 20 years on my core business, 50s Aston Martin's getting the hp up from 77 hp per ltr (61 CI) o 92.5 + bhp per ltr (61 CI). I can look at the figures & see if they were BS, I could also have new tests carried out as one of my apprentices carries them out & my companies ex employee owns the rig but I'm unwilling to give them any advantage in my field, engine building.

[MRN I J]

I found the airflow sheet, it doesnt record the size & type of inlet valve tested, nor does it record exhaust flow at all so its all rather irrelevant.
I'll have to have some new test done, but more likely i'll speak to our (retired) head guy and ask his advice then use my own intuition to get the head ported the way it should be.

[Valerio Leone]

I don't have any air flow results, the head has been prepared by an engineer that is working on Superbike championship.
In general the port design on an wedge head is just horrible, that is why the guy had to use Devcon to straighten the general layout.
I dont have anymore this masterpiece, Serge from Belgium have it now.
I think he will enjoy the 123HP and at the same time the huge torque that the engine provide.
My new setup is made with a Xflow head. more than 160HP is now pulling my Europa but the usable range is between 5000 to 8000RPM. unusable on the road.

[dakazman]

Thank you Valerio,  I’m really just happy to learn and do an engine build step by step. Understanding why I did , what I will do is based on all the experts I’ve talked to and what I read. I also understand the limitations of this engine.
 Dave Kaczmarek

[MRN I J]

There are at least 3 'wedge' heads, we call them bathtub chambers.
Chambers are largely the same but need improvement to flow better around the larger inlet valve, the 1st photo is a Europa head which is awful, the 2nd photo is a R16 head from the late 70s, which is better.
The last photo is from a Renault Traffic circa 1981, this could be a really good head with its round inlet ports & square exhaust ports, I already know a crossflow head flows around 118cfm on a small Superflow (110?) flow bench, this would give 170+ bhp, if a non crossflow can be got up to somewhere near 110cfm & beyond it can give really good power.
The heads really need checking on a bigger machine as it's been found that the bigger machines give a more real world result.
I have a 45DCOE on an Else manifold, this can easily be modified to fit the later Traffic head, however it really needs twin 40s or 45s to make it really work, exhaust manifold would be 4 into 1 as it often gives more midrange with better low down pickup than a 4 into 2 into 1 system

[dakazman]

MRN,  thanks for posting that information .
Dakazman

[lotusfanatic]

Hello MRN,

I am interested in keeping a wedge head on the 1470 engine in my car and I would like to find the best variant of this head.
Thanks for posting the photographs,

Mark

[MRN I J]

Not easy to find 40 year old R Traffic heads though

[MRN I J]

wedge heads were still being used on new vehicles until the late 80s, in round port form to R18s, Trafic's & others.
although the round port looks best in reality the late 70s square port, what I call the middle head might be the one to use with the top of the port made into an arch (D laid on its side) as it looks as though it would promote a great deal of swirl, the round port has less but still some port induced swirl, both heads induce swirl into the centre of the cylinder away from the cylinder wall, only flow testing will prove which head to use but I have 2 mid heads & only one late head.
The biggest inlet valve ypu could use with either head is 41mm using a MECA PARTS 82.5mm bore head gaskets and a lot of head mods, this would entail the fitting of new valve seats, an easier & better inlet valve to fit would be 40mm, both 41 or 40mm inlet valves need a 31.5mm exhaust valve, it would need a new seat fitting as the heads are at least 32/33 years old.

[MRN I J]

Help Needed:

My S2 was an Else converted car, I have the inlet manifold & Weber carb, if anyone has an Else rocker cover they would be prepared to loan me for a few weeks so I can get a casting pattern made it would be much appreciated, thanks
Chris Adams

[MRN I J]

Looking at the middle head (R16 821) the inlet / exhaust manifold bolt pattern is the same as a 697 early head, which means that the Else inlet manifold fits, just need to work out how to get the head to work with that inlet manifold - does it need port dividers welding into the manifold or not ?, a new manifold will need to be made to get the later head to work, but i've almost made uo my mind to make (fabricate ?) a twin Weber 45DCE Hermes conversion for the later head then I can race on similar / reasonably equal terms with the TC's in HSCC roadsports before I get too old and keep the rebuilt original engine on the shelf

[MRN I J]

Help needed :
can anyone tell me the distance between the manifold face (on a wedge) & the fuel tank on an S2 as mine isn't in one piece just now

[dakazman]

Can you project a line down from where you want the measurement to the glass body? I can install my tank and give to a measurement from there . I don’t have the engine or tank installed.
Dakazman