while my cars out of action i've took my manifolds off to have a go at porting them, but i've got a few questions;

1. how much can you safely take off/need to take off?

2. what's the easiest way of getting all of the manifold done (drill will only go so far), can you use those flexi extentions?

3. do you port the exhaust ports on the heads aswell as the manifold?



kev :)

Kev, you dont need to go all the way down when porting.

When you take the headers off, you get a darker ring where they dont match up to the heads. This is where you need to open out to.

All you need to do is open it up, i.e. instead of a step, you give it a slope.

Use someing like a die grinder.

Dan

that's what i thought when i took them off but the gasket is 2-3mm bigger than both the ports (hard to describe, but the ports both seem to be the same size :confused:)


i did take the ring out of the bottom of the uppipe and smooth off the step :)


kev :)

You can actually enlarge the gasket... Hold the gasket to the head and have a look... it only needs porting in the direction of flow... You can remove far more than 3mm in places... Use a tct cutter in a die grinder... a drill doesnt go fast enough really...

David

so we're safe to port the head and the manifold 3mm, i.e. 6mm bigger diameter?

how deep do i need to go from the heads into the manifolds?


kev :)

As far as I know you are... but I would only port the head off the car.... wouldnt even risk getting sh1t in the engine... but you could tape it all up I suppose...

go as far as you can making the slope gradual, thats what I've done anyway.

David

just finished them off today (did the uppipe also), exhaust wrapped it up aswell :D marks out of 10 ;)

http://homepage.ntlworld.com/horsley...anifolds-1.jpg


kev :)

10 out of 10 for the porting... what did you do it with? looks better than mine :eek:

How much was the wrap and where from?

David

[Edited by David_Wallis - 6/16/2002 7:41:21 PM]

What about the link pipe from LtoR, The expansion sleeve inside does reduce the diameter of the exhaust link quite a lot. Does anyone do a replacement for this, since we are all bothering to port the manifold, and get uprated 'up pipes'.
Have to say, doing the manifolds on my mates car, we didnt really notice any difference!! Im still gonna do my own as well anyway, coz mine just doesnt have as many goodies as his engien, so i might feel the difference more. I didnt port the head to match though, although I am going to be doing this on my car, since the engine is in bits anyway. Gonna do a simple clean up around the valve seat/throats also. Nothing to dramatic, coz I will only make a balls if I get too carried away with it.

got the wrap from autosports exhibition last year, got it at trade price, normally 60 quid i think (only used half of it on the manifolds, the rest will go on the new DP)

angle ground off all the heat sheild bosses (weight saving ;)), wrapped it then sprayed with heat resistant paint to seal it from oil etc.

ported them with grinding wheels then just used a sandpaper flap thingy for a drill to finish them off :D although i did use emery tubes & a polishing mop for the heads (aluminium is easier to polish)

i'll put some more pics up in a minute


kev :)

just a quick one of the heads

http://homepage.ntlworld.com/horsley.../porting-1.jpg


kev :)

Sad but that looks really nice... almost something to be proud of. :)

David

i'm dieing to try the car out, just need to put the gearbox back together :rolleyes:


kev :)

I bet the manifold will smoke like crazy for the first few miles. Be prepared for comments like " I think your cars on fire mate" ;)

F
PS nice work!

Kev

Nice job - not sure about the paint on the exhaust wrap, but it certainly looks neat.

Tell me that you took the heads off before grinding them out!

Duncan ;)

Duncan, I believe that he used cotton wool to bung his ports whilst grinding away at them in situ(ooh er misses). Remember that the ports are vertical and waste material should fall out anyway.

F

paint on the exhaust wrap is standard practice to seal the wrap against oil etc.

i'd like to say that i took the heads off but..........did what was said above :rolleyes:


kev :)

btt to remind myself and others :)


kev :)

Looks fantastic.

I'll send mine straight down!! :D