NA intake runners vs turbo

Post by **Sveedy** » 17 Sep 2020, 18:40

I came across a '94 na 850 in the wreckers yard the other day. I've been thinking of doing the na intake/throttle body etc mod but this intake had some sort of linkage system between #3 and #4 runners so I left it. My question is; is there a difference in the size etc of the intake runners between the two intakes ? Or is it strictly a difference in bore openings where the throttle bolts on ?

Post by **FLXC90** » 17 Sep 2020, 20:44

IIRC the plenum and runners are the same. The t/b inlet is choked down, maybe for off-boost velocity? I've seen where people have bored the turbo manifold entry. Also, the 93 and some 94 manifolds were double ported with variable volume intake system (VVIS)that would be the linkage you saw, two sets of runners in one, operated based on RPM and Load.

If you're in to it, that motor has the preferred cams for swap into the T-5 motor!

Post by **Sveedy** » 17 Sep 2020, 23:18

Well then maybe I'll grab them. Question - What is the usable lifespan of the cams ? The car at the wreckers has 160K on it. Looks like catastrophic engine failure due to timing belt breakage.

Post by **abscate** » 18 Sep 2020, 01:12

That Variable intake manifold has got to be hard to find and I’m guessing NLA from Volvo. Grab the whole thing!

Post by **erikv11** » 18 Sep 2020, 10:40

But who wants VVIS??? No P80 manifolds are still available from Volvo are they?

Get a 95+ intake manifold, straightforward.

callahanoffroad · Post by **callahanoffroad** » 18 Sep 2020, 10:57

I have a variable intake manifold it's great when the thing actually works. Otherwise it's got no get up and go in the bottom end

Post by **Sveedy** » 18 Sep 2020, 11:12

If the only difference between the two manifolds is the throat opening, then I'll bore out the opening on my turbo manifold. That way I don't have to spend $50 buying a different ( na) one. And I believe I'd still need to drill/tap that one for vacuum lines anyway.

Post by **erikv11** » 18 Sep 2020, 11:45

Yes, one solution is to bore out the turbo manifold.

Post by **abscate** » 18 Sep 2020, 11:54

I don’t have time to sit next to my manifold all night reading “Great Expectations”

Post by **Sveedy** » 18 Sep 2020, 14:00

Guess I'm a fast reader

With the way I'm planing on doing it, I should be done in a bit over an hour. Most of that time will be spent in set up.