Modifying The Inlet Port

[DamirGTI 325]

Hi!

 

Can some one tell me is it oright to do this on inlet and exhaust port ? :

 

http://i27.photobucket.com/albums/c151/Pie.../Picture201.jpg

 

http://i27.photobucket.com/albums/c151/Pie.../Picture203.jpg

 

i have bend this sharp edge , also do the port match (inlet mainfold to inlet ports) and lightly polish ports on inlet side..

 

cheers

[sutol 0]

The most benefit from least effort there is to blend the steel of the valve seat into the aluminium of the port giving the airflow a smooth path without the step which is present at the moment.

If you haven't got carbide cutters then a stone will do it, take care to blend it in and flow will be much improved without messing with polishing.

 

 

 

edit crap spelling

Edited January 22, 2007 by sutol

[DamirGTI 325]

edit crap spelling

 

sorry i'm from Croatia - still learning to write english

[sutol 0]

If you can imagine the air rushing up the port then the first obstacle is the valve stem and guide, then the air turns downward and some of it hits the step which is the steel of the valve seat. This causes turbulence slowing the air as it negotiates the passage into the cylinder.

Next major obstacle is the wall on one side which is the divider beween the chambers shrouding the valve on one side when it is open.

Blending the valve seats and cutting back this dividing wall to the line of the head gasket on the most shrouded bit will produce more power than opening up and polishing the port upstream near the inlet appertures.

Precision and care in these areas is the way to go for cheap and easy power increases.

Works for me

was meaning my spelling lol

Edited January 22, 2007 by sutol

[DamirGTI 325]

sounds oright to me too

i didn't wish to enlarge any part of port

[Malachy 0]

i have been doing a fair bit of reading on diy porting as i plan to do some myself on my 16v turbo conversion,

 

some good sites to read a bit of info on are :

 

here especially this bit with a bit of info on how to identify where to port using a thread.

 

This is for the c20let but again some usefull info

 

this Again is worth reading.

 

now i know the results are unlikely to be as good as a "pro" ported head but i enjoy doing everything on my car myself, hence the ecu, the fact im making my own manifolds etc etc. I like learning new things and with my background in engineering i am happy to take on most jobs.

 

i would advise though you should practice on a scrap head first really as you can run into oilways etc and trash the head. Not advisable really.

 

Regards

Andy

[sutol 0]

,

 

 

would advise though you should practice on a scrap head first really as you can run into oilways etc and trash the head. Not advisable really.

 

Regards

Andy

 

Good idea but if you keep metal removal to a minimum then you will be OK

I find that the only time serious port enlargement is required is when high revs are used to produce power.

Huge power increases lower down the scale are possible if care is taken. It is the attention to detail that gets results I find.

But there again thats my opinion and what I personally have found with my own work.

[DamirGTI 325]

wow! great links

 

i have one spare head for practice

 

thanks man !!

[sutol 0]

,

 

some good sites to read a bit of info on are :

 

Yes , great reading mate, good reference sites.

Not impressed with the butchering job on the valve seats though, but maybe I'm too fussy

[sutol 0]

i have bend this sharp edge ,

 

 

I see what you mean now

 

Yes you have taken a bit off the short radious dropping into the valve seat area which is good. It is important to have a smooth radious here rather than a sharp drop. I have never ported a 205 head so I cannot say how much can be taken out at this point but I would personally try and remove some of the ridges in that area so that any protusions etc are as gentle as possible. You can get a feel for the airflow with your finger and much can be done with emery paper and a sensitive finger, but then you can read all this on websites so I'll shut up whilst I'm ahead

[DamirGTI 325]

any advice will help mate !

 

yes that edge is very sharp step on both inlet and exhaust port so i smooth it up

i will continue doing the rest bits tomorow - much wiser now

 

thanks

[Ahl 4]

The lower bend (or short side radius) in the 8v ports is quite sharp.

 

I did some DIY porting to mine concentrating on that and generally tidying everything up. The car made 110bhp at the wheels (roughly 134hp @ fly) on an accurate rolling road, so it is worth having a go.

 

I'd really like to get myself some sort of flowbench for comparing mods and port shapes.

 

Have a look at these very good websites for even more information:

www.pumaracing.co.uk

www.guy-croft.com

[DamirGTI 325]

I did some DIY porting to mine concentrating on that and generally tidying everything up.

 

my point egsaktiy

134hp that's not bad , considering that standard 1.9 8v engine rearly produce claimed 130hp

 

thaks for links , aldhou i have read all "PumaRace" articles before

 

cheers

[Ahl 4]

Make sure you check out Guy Crofts site though. Im sure it has an indepth explantion of how to port the 8v, along with fairly detailed pictures.

[DrSarty 90 1 Cars]

Thankyou and Grrrrrr!

 

This thread with its embedded links has proved fascinating. I had no idea people used a cotton(?) thread to visualise flow in/into/out of a cylinder head etc. I see the logic but had no suspiscion (spelling gone astray - tired) that people did this at home!

 

It's given me a heads-up as to how brave some of you are in modifying your own cylinder heads, and how clever (also read: experienced) certain individuals are such as Guy Croft, Dave Baker aka Puma and the bloke behind this web site are.

 

Respek!

 

That doesn't mean others on the forum aren't switched on cookies either; I'm just throwing a few names in that spring to mind regarding both the specific subject of head mods and the overall subject of performance engine tuning.

 

In fact I'd go as far as to say - and here I actually would primarily blame the marketing behind certain wonderous, power adding mod products, trends and methods - that I can almost understand the demeanour and apparent attitude of the likes of certain individuals who kind of get ratty at people when they have clearly but innocently been taken in by said bunk!

 

I can't locate the author's name of the above site (the link), but I had a tickly, annoying cough in bed about 3 hours ago and only came down for a drink . Nuff said - what a highly entertaining, educational, well researched and above all honest site. I simply cannot recommend enough a comfortable seat and several visits to this site.

 

If this site has been recommended before then I apologise, but despite not focussing at all on anything Peugeot (or indeed French), it covers everything from the useless mod cycle which is all encompassing and frank (been taken in me ) to book reviews on where and how he has built up his knowledge. And he's not backwards in coming forwards either in crediting everyone who's ever helped him.

 

Thanks to this thread, MALACHY and DAMIR with his sh1tty spelling (ha ha SUTOL I RLMFAO at that earlier mix up), I and anyone else who is often hoovered up by what I can only describe as hype, can well and truly become better educated IN ADVANCE, and not be duped into buying complete crap (wasting hard- earned cash) and dare I say it annoying the f&ck out of very clever people who perhaps have run out of the patience needed to deal with the innocently ignorant, that the marketing fraternity prey on.

 

Rant over. Oh the benefits of a real-world education, only realised too late. But I AM trying!

 

Rich

Edited January 24, 2007 by DrSarty

[DamirGTI 325]

Make sure you check out Guy Crofts site though. Im sure it has an indepth explantion of how to port the 8v, along with fairly detailed pictures.

 

Guy Crofts site - great ! i've been hanging all nigth till morning on that site reading , seen some pic of 1.6 head , yes great thanks

[DamirGTI 325]

Rant over. Oh the benefits of a real-world education, only realised too late. But I AM trying!

 

Rich

 

never tired of learning there's always something new too know abaut this subject ..

i've been read some books too i can especially recommend this book : "FOUR STROKE PREFORMANCE TUNING" by A. Graham Bell great book allthou it dosent have too much D.I.Y stuff , but great read

 

i will post some new pics of my head work later

 

cheers

[Malachy 0]

i've been read some books too i can especially recommend this book : "FOUR STROKE PREFORMANCE TUNING" by A. Graham Bell great book allthou it dosent have too much D.I.Y stuff , but great read

I'd reccomend all of "A.Graham Bell" books i regularly refer to "forced induction tuning" I imagine there is a fair bit of overlap in all the books but also a fair bit of new info.

 

they are very well written and explainations are easy to understand for anyone with a small level of technical aptitude.

 

im using his formulas and tables to design my inlet/exhaust manifolds for my 16v turbo head conversion

Edited January 24, 2007 by Malachy

[DamirGTI 325]

some new pics :

 

before

http://i27.photobucket.com/albums/c151/Pie.../Picture026.jpg

http://i27.photobucket.com/albums/c151/Pie...icture030-1.jpg

http://i27.photobucket.com/albums/c151/Pie.../Picture024.jpg

 

after

http://i27.photobucket.com/albums/c151/Pie.../Picture011.jpg

http://i27.photobucket.com/albums/c151/Pie...icture001-1.jpg

http://i27.photobucket.com/albums/c151/Pie...icture007-1.jpg

http://i27.photobucket.com/albums/c151/Pie...icture008-1.jpg

 

comments please is this of any good ?

 

must get valve guides out and work around them ....

 

cheers

[Ahl 4]

You seem to have modified the most important bits, although its impossible to tell how smooth it is from the pics.

 

As long as you haven't gone crazy im sure it must be fine.

[DamirGTI 325]

yes i know it was also difficoult to take a good picture

 

...beasicly i didn't remove too much metal , just focused on smooth sharp edges in throat and under the valve seat

just hope i didn't mess something up

 

cheers

[DamirGTI 325]

little update

 

finished with basic head porting :

 

inlet mainfold :

http://i27.photobucket.com/albums/c151/Pie...etmainfold1.jpg

http://i27.photobucket.com/albums/c151/Pie...tmainfold11.jpg

arrow is pointing on the square area which i have remove .

 

inlet port entry :

http://i27.photobucket.com/albums/c151/Pie...inletports1.jpg

http://i27.photobucket.com/albums/c151/Pie...nletports22.jpg

same thing arrow is pointing on the area which is removed to mach the inlet mainfold on head .

 

combustion chamber lightly polished :

http://i27.photobucket.com/albums/c151/Pie...tionchamber.jpg

 

valve throat little reshaped and removed ridge wich was deep inside the throat :

http://i27.photobucket.com/albums/c151/Pie...valvethroat.jpg

 

around valve seats :

http://i27.photobucket.com/albums/c151/Pie...dgeremoved1.jpg

arrow is pointing on the ring around valve seats where was a small edge between the valve seat inserts and combustion chamber which i have remove and smoothed ..

 

short side radius on two inlet ports :

http://i27.photobucket.com/albums/c151/Pie...ninletports.jpg

smoothed ( with three diferent grades of sanding paper ) and bend in the valve throat .

 

short side radius on two exhaust ports :

http://i27.photobucket.com/albums/c151/Pie...xhaustports.jpg

also smoothed ...

 

beneth the valve seats inserts :

http://i27.photobucket.com/albums/c151/Pie...s/valveseat.jpg

arrow is pointing on the area where was a sharp lip which i have remove and smoothed .

 

and some more picture of the head :

http://i27.photobucket.com/albums/c151/Pierrepenis/head.jpg

http://i27.photobucket.com/albums/c151/Pie.../Picture085.jpg

http://i27.photobucket.com/albums/c151/Pie.../Picture087.jpg

 

i know is not so much , but something must hapend now

only three angle seats left to do

[Ahl 4]

Pics looks nice - you've done a hell of a lot more than I did!

Goodluck with it, you definitely deserve some increase.

[DamirGTI 325]

Thanks man !

 

I have register on Guy Croft's site and show him this pictures and he's exsamine my work and sead that all this job wich i have done on this head is fine .

 

cheers

[PumaRacing 1]

Although it's hard to tell much from pics what you have done so far looks pretty good. The 205 head is a fairly common sense one in that for basic mods what looks right also works fairly well. Other heads are not so easy to do and I can guarantee you that if you tried to port a CVH or Pinto you wouldn't get anywhere near optimum without being told what to do or spending ages on a flowbench.

 

If you get the seats and valves right too you'll have achieved a good power gain on this head.