29 replies to this topic

[mini-geek]

I see your point, but looking at the 7port heads like MED and MiniSport they both seem to have tight angles on the two outer inlets the SC one hasn't so on paper should be better. But I don't know how important that is.

oh and IIRC the MED head is only sold as a dry deck so don't forget the block work costs.

[stardude]

yeah the MED head is sold as dry deck. it also comes with the dry deck kit they charge £150 quid for. link

upon talking to them, they said that no work needs to be done to the block waterways, other than the core plug on the left of the engine for the drydeck feed. this is due their head gasket which they provide, which has no waterways through it, so blocks off the waterways in the block.

i think it would be best to get the block waterways plugged, as that means i can use other headgaskets if needed, as well as the fact that i thought the purpose of dry decking was to stop any water contact with the deck/head face??? to prolong headgasket life, aswell as allowign the engine to limp home, without oil and coolant mixign and going into the worng places.

although if i didnt get it machined, if needed i could run other heads.


i will be using this stack and filter kit from them but with a larger filter. this is compatable between the weber 40's and jenveys. link




ohh and if and when i want to go to jenveys i can buy this kit minus the filter, for £950 link

[AndrewJ530]

I'm thinking of a 7 port for my project in the next coming year so this thread has answered some questions i had but, what's the real advantage of jenveys over the webers? Do you get a massively noticable power difference? I know you'll get slightly more power but there is an engine tuner near me that's an official stockist of webers so he practically has them coming off the walls so i won't have to pay through the nose for a pair of 45's.

I realise that if you went megasquirt then you also get the mappable timing aswell but i was planning on using megajolt anyway so this would make no difference. Sorry to jack the thread but i think it's closely linked.

Cheers,

Andrew

[richieg]

Will a 7 port with twin 40s fit under a std roundnose bonnet?
What filtration will you get away with or will it just be the mesh covers?

Slightly off topic but can I ask what cam are you planning to use?

[Turbo Phil]

Have you had a look at the HRE 7 port head ? Cheaper than all the others. HRE 7 port.
This is where I've ordered mine from, I will be using a single throttle body which was £10 from the scrappy, I'm Turboing as well.
Dry decking the block is easy, the waterways can be tapped & grub screws inserted, simple & cheap. Dry decking.

[mpihornet]

To be honest, considering the cost of a set of carbs, I'd go straight for injection.

Buy this book http://www.amazon.co...-...9215&sr=1-3

There are cheaper options than Jenvys.

Second that! what about taking a motorcycles engine management system? the pros are, cheap, compact, already sorted on the maps, and yet still lots of tuning options...

it would be pretty easy to do early kawasaki injection, its a 4 injection system, just needs crank angle, engine temp and throttle position and a nipondenso air flow meter with air temp in it, and spits out timing and fueling signal.

next option would be bmw k series injection, but it may need lambda sensor as well.



or for even cheaper, a set of motorcycle carbs until you can afford injection, you should be able to get like a set of kehins from a 1100 cc bike that are essentially tiny su's or a set of flat slides that will sort you out from a breaker for pretty cheap.

[richieg]

I've been waiting to hear what Paul was performance getting out of his. Do you know?

I did not know the HRE version had to be dry decked, are you sure?

Do all 7-port heads need to be dry decked?

[Turbo Phil]

I don't think it has to be dry decked, no. But I've already done my engine So I'll be keeping it with this head to.

[mini13]

oooooohhh,

joining the club eh Phil,

[stardude]

im pretty sure the HRE head is the same as the one MED provide, but with standard valve sizes.

Webcon sell the 7 port head with std valve sizes for less than £1000

[richieg]

I think HRE are working on a fast roas head as well as the std one.

What valve sizes are in the webcon one compared with MED version?
How would the std valve head compare with say a Rally special or clubman MED head for performance?

[stardude]

the webcon uses std 1275 unleaded valves. the med head uses 37mm inlets and 30mm exhausts.

i dont know how the std head flows compared with a 5 port, but MED's trackday/hillclimb head produces 22% more flow, than the best fully modified 5 port head

[jayare]

I know it's boring but it may also be worth considering the additional fuel costs from running carbs rather than injection. You'll also get a more drivable engine (or be able to run a bigger cam without sacrificing drivability) from going injection.

JR

[AndrewJ530]

Surely with webers you could get them to fuel pretty well with all the interchangable jets and chokes and what have you. Obviously need someone who knows their way round a weber though, not some heavy handed fool who'll 'dive in and have a go'.

[samsfern]

definately twin 40's or bike carbs!