bridge vs. extended port

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tj19985
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bridge vs. extended port

Post by tj19985 »

i am wanted to build a 12a for my dd. my question is which would be more reliable and practical ? also would it be a good idea to run a turbo without low compression rotors?
biznatch
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Re: bridge vs. extended port

Post by biznatch »

An extended port should be more user friendly as a daily driver. Full bridgeports idle high and are loud as a rule and low end torque is compromised - that said they come into their own later in the rev range. f-f
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Re: bridge vs. extended port

Post by TOOL »

Can of worms now wide open lol
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Re: bridge vs. extended port

Post by Lucky »

My personal experience is that the irritation of a bridgeport doesn't compensate for the few times you can get it on full honk on an open road. But then, I use my cars for pottering around shopping and plodding to work as much as for ****s and giggles. For me (and I stress this is only a purely personal opinion), the poor low-down manners of the bridgey are too intrusive and annoying for everyday use. But then, maybe I'm just too milky :oops:
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Re: bridge vs. extended port

Post by TOOL »

In my opinion, I think this is looking too black and white.

There's bridgeports and then there's bridgeports. Full bridge. Half bridge etc.

You can get away with a reasonable size BP on the street. It comes down to personal preference. The bigger the BP, the harder it will be in traffic. I have a pretty big BP in one of my RX2s. It idles at 1500rpm all day. This isn't an issue imho.

Here is a pretty big 13B BP:

Image

Image

It really doesn't like low revs. But how much of this is down to the fact that I am running an IDA?
With an IDA, you lose the primaries and secondaries. But with a Niki carb, you keep the primaries and secondaries and therefore you can extend port the primaries and BP the secondaries, giving you the best of both worlds.
For me to do this, I need to source a 13B Nikki manifold, which are few and far between in the UK.

My 2 cents.
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Re: bridge vs. extended port

Post by RamoNZ »

Who said worms?? Lol

You forgot drill bridge, full and partial eyebrow too.

Low down manners comes from a variety of factors aside from the above - vehicles weight, gearing, exhaust and inlet tuning, fuel atomisation and port/runner separation.

In saying that, I'd say get an extendy and equip it with the best outside bits and you can't go too wrong ;)
1980 Series 1, Minty Pea Green 13b Turbo
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