Porting And Polishing Cylinder Heads On A 1.6 Gti

[Atari Boy 11]

I need some advice/opinion please.

 

I need to take the head off my 1.6 GTi and the stem seals have gone and need replacing.

The car is weekend toy that has done 153k so I dont want to spend too much time/money on an engine that is in the departure lounge of life, ultimately I will upgrade to 1.9 lump.

Whilst the head is off though, is it worth porting and polishing the head? I have read the information on the Puma Racing website, which is very detailed and informative but mainly concentrates on the 1.9 lump. Obviously if there is no advantage in doing it or there is a risk or reducing power then I will leave alone.

 

Any advice or views would be appreciated.

[Richie-Van-GTi 71 2 Cars]

it would be worth it as the head can be used on the 1.9 lump as well, done right there are gains to be had although mainly in conjunction with other mods such as carb, TB's etc.

[Anthony 1,003]

1.6 and 1.9 heads are the same, so what applies to one applies to the other.

 

Pumaracing's site sums it up pretty well though - good headwork is worth having, but there's alot of people out there who'll make the head flow worse rather than better.

 

A few people have had success using an XU10 head (do a search) from a 2.0 8v as these have bigger valves and flow better as standard - there's been a topic in the past week or so if I recall that explained alot about it, and there's loads if you do a search. Won't flow as well as a fully ported XU5/9 head, but will give a nice improvement for comparitively little cash.

[Atari Boy 11]

Thanks chaps, useful advice.

I forgot that the heads were the same on a 1.6 and 1.9.

[PumaRacing 2]

If you want to do a bit of porting yourself just try to blend the short side turn on both inlet and exhaust ports into a smooth radius leading away from the seat insert. Don't touch or enlarge any other parts of the port especially the straight bits leading to the manifold. You won't improve anything there at all. You won't know what ideal shape or curve to aim for but you'll probably find a few bhp.

[Ahl 4]

Just as Puma says, thats exactly what I did to mine when I had to do the stem seals etc.

 

I also did the valve shims and relapped the valves while I was at it. My 1.9 made 110bhp at the wheels (approx 134hp@fly) at a reputable rolling road. A worthwhile improvement.

 

BTW Dave, did you get my email?

[PumaRacing 2]

Nope because my email is blocked. Try a PM.

[Atari Boy 11]

Puma and Ahl, thanks also.

It is refreshing to come across a website such as Puma Racing, as a new boy it can be bit of a mine field and your straight talking attitude is refreshing. You also write in manner than can be understood by a novice.

 

Thanks to everyone for the advice.