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single port? twin port?
BLUE_62 - June 1st, 2005 at 03:09 AM

I currently have a 1600 single port
(1300 with 1600 bore).

Is it worth my while getting twin port heads fitted
or will a nice cam, 009 dizzy, good exhuast and a decent carby do the trick?

I thought seeing the case has to be split to accomodate fitment of a new cam i might ask the question now, and get some good twin port heads fitted up at the same time..

i dont see point if the added expense is not justifiable.

Any advice or comments welcomed. ;)

Dasdubber - June 1st, 2005 at 08:20 AM

I would strongly recommend twin port heads - no point having a lumpy cam if you don't have the flow to fill the chambers quick enough (within reason of course).

Just my 2c but I'd say go with some twin ports.

PurpleT3 - June 1st, 2005 at 08:25 AM

Twin ports. Much easier to install, and more bang for your buck.

lugnuts - June 1st, 2005 at 02:21 PM

Single carb or twin.:duh

BLUE_62 - June 1st, 2005 at 05:43 PM

It'll probably only be a single carb set up.
Dont want huge power, just fun power.

And trying to keep budgets down and i know a good set of twin carbys will cost me 500+

Looks like i'm gunna be finding me some twin port heads.

Cheers guys. :thumb

Chewy - June 1st, 2005 at 05:47 PM

Just things I have heard..
SP gives better bottem end torque, DP gives better top end HP
SP seem to be more reliable.
The stock VW cam is the best for a stock engine, putting a lumpy cam is just going to move your powerband higher up.. which isnt really what you want on a stock 1600

lugnuts - June 2nd, 2005 at 02:34 AM

I woudnt worry about a bigger cam if your staying single carb,its under carbed already.;) and twinport heads are only an advantage with twin carbs.

VWCOOL - June 2nd, 2005 at 10:18 AM

Do you have a 009 distributor? Extractors/exhaust?

[Edited on 2/6/2005 by VWCOOL]

Dasdubber - June 2nd, 2005 at 11:58 AM

You also have to think about potential future upgrades - that is one day you might go with dual carbs etc, so rebuilding wtih single port heads now may restrict what you do down the track. I know its only a 1600 with single carb, but I still think twin ports win hands down.

VWCOOL - June 2nd, 2005 at 12:08 PM

yeah, but not on a worn-out SPR case... ;)

pete wood - June 2nd, 2005 at 04:41 PM

Quote:
Originally posted by Chewy
Just things I have heard..
SP gives better bottem end torque, DP gives better top end HP



I agree with this. I had two almost identical donks. Both 1640s. Extractors, 009 and a 30pict. One was SP ands the other DP. The SP pulled off the lights heaps better, but the DP would rev out to 5k, if pressed.

Of interest, Class 5/1600 in the US offroad scene has to use SP motors and they get 80 plus HP out of them with mostly stock parts. And they thrash them. That is with a slightly offset ground crank for exactly 1600cc, but even still, with a single carb they go hard. Not sure of the cam they use but it's not standard either. Look up some specs on one on the net somewhere. I try and find some specs in a mag if I can.

Do a search on 'Adam Wik' racing engines, you should find something. He's the top 5/1600 guy I think.

Oh the other thing to remember is this. A single carb motor self regulates. So you can hold your foot flat and it shouldn't over rev valve bounce. The carb chokes it enough to rev limit it. This is what helps VW motors last even when thrashed.

[Edited on 2/6/2005 by pete wood]

BLUE_62 - June 2nd, 2005 at 05:33 PM

I have to be honest i have given my a fair old flogging at times and have found that high up it just floods itself causing the motor to lose forward motion, snap next gear, tyres chirp and away you go again!

I have toyed with 2 x 1600TPs on 2 occasions now and both seem to get legs off at the lights and up top end.
I love my motor and i would do nothing to wreck it.
I would just like it to be ultra reliable and have that little bit extra to out power an unsuspecting P plater at the lights.

Yeah yeah, i am the traffic light grandprix king. :thumb

pete wood - June 2nd, 2005 at 06:01 PM

It will run rich, cos the jet acts like an open pipe once you get to much air flow, but it shouldn't flood.