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Different intake manifold

There is some debate over which manifolds flow better, but IMHO on a NA motor you're not gonna get a noticeable improvement by changing the intake manifold. Camshaft and exhaust is your best bet, you'll get a lot more bang for your buck, a different cam can completely change the personality of the engine.
 
Longer runners usually mean better torque but it all depends a lot on the camshaft they have to work with.

B230 style manifold worked best for me running K camshaft on na B21 with K-jet.
I used a crude "flowbench" awhile ago and compared 4 different manifolds (b21, b21ft (the worst), b230 and LH1.0) aiming for best high RPM power since that's what the K cam is for.

Mating the injection system with B21 manifold may be too much work for the torque you may gain.
 
Longer runners usually mean better torque but it all depends a lot on the camshaft they have to work with.

B230 style manifold worked best for me running K camshaft on na B21 with K-jet.
I used a crude "flowbench" awhile ago and compared 4 different manifolds (b21, b21ft (the worst), b230 and LH1.0) aiming for best high RPM power since that's what the K cam is for.

Mating the injection system with B21 manifold may be too much work for the torque you may gain.

I've heard the b21 manifold flows about 10% more than the b230 one. Were you able to verify that? As my welding skills improve, I've thought about modifying one for efi and a larger throttle body, like this http://forums.turbobricks.com/showthread.php?t=333469.

I agree with the "probably not worth it" assessment, but I would really like to know if it actually moves more air.
 
Larger throttle body very rarely helps anything, all it ends up doing is making the throttle response more twitchy. If the OEM one were undersized it would help to go larger but with Volvos that is not generally an issue.
 
You will want a head and cam combination that actually flows a decent amount before worrying about manifolds.
 
To Kenunot: No, what I saw made me want to choose B230 style manifold for high RPM flow. But low RPM torque (probably that's what the OP is after) is not about overall maximum flow at all- it's mostly about moving the max effect of dynamic supercharging (Helmholtz, pressure wave resonance) down the RPM range.

Never saw any numbers on different manifolds, would be interesting to find info on that 10%. May be it was on forced induction?
 
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Is there any intake manifold that would increase torque on a na b230 ? Why do some use a b21 intake?


Torque, for a given fuel is pretty much a function of engine volume x corrected compression ratio--aka dynamic compression...

People use B21 because what is correctly called "inter-net Lore"..

It works by making up anything you want, and repeating "I like how my car goes!!"

It works by also whining and calling anybody who innocently asks just how whatever claim it is an ******* or a know it all or I love this one "an elitist"...

You din't say it but I 'll venture a guess that you have a n.a. B230 and it is so slow you routinely nod off asleep because it is slow, right? I know what you're suffering from cause my daily is a 88 wag-goon with 300,000 miles a long time ago..

Easiest answer is:
1)pull the head, and have a mchine shop chop about 060" or 1.5mm off
2) get a cam from same place I'll be getting 2 or 3 cams in Sweden..
Why? because the vast overwhelming majority of all the guys here only f**k around a little on turbo cars and mostly concerning themelves with drag racing...

So they always answer every inquiry with "Plus Tea it"...
Then there's all the kids who have never changed a cam who just repeat s**t to hear their head rattle who always say "get this_____________ cam, I LIKE it" and the cam is always either some emission cam or copied emissions cam with lob centers diddled or some such stuff..
And the results are what has been described as "limp dick" performance..

You can pull the head yourself.. Machine shop might charge $80-100 to hack off 060..
Cam maybe around $275 with airmail and everything...

If you want do do something with the manifolds either throw them all away or weld in substantially larger runners.
 
"Flow" mein beliebt Peruvianisch amigo is all about higher Are Pea Ems..

Im think your native word 'drehmoment' gives a better idea what we'ze after

Right, but the manifolds do not present a restriction on a 530 head with an emissions cam now does it, Opa Jan?

Which is, like, 30% on an NA car.

That was on a turbo motor running a fair amount of boost iirc
 
Right, but the manifolds do not present a restriction on a 530 head with an emissions cam now does it, Opa Jan?

Yes it does give a LOT of restriction on a original 530 head with any factory cam. Just changing the manifold can see around a 30BHP gain!

For towing power run as much CR as the fuel you use will allow. 4-2-1 tubular manifold with a 2.5 inch exhaust. The K jetronic manifold is teh best of teh factory manifolds. Cam wise of factory cams you want to go for A, D or V cam
 
Id get a different ring and pinion setup over exhaust, intake, cam any day.
What gears do you have now?
I have 4:11 on a completely stock 245 and it'll spin the tires off the line like nothing.
 
Id get a different ring and pinion setup over exhaust, intake, cam any day.
What gears do you have now?
I have 4:11 on a completely stock 245 and it'll spin the tires off the line like nothing.

Good point.. We din't even ask if the poor boy has a slush-o-matic or what...My wag-goon is geared so sky high that it below peak torque at 75mph and hence a dog..And since I'm not doing primarily cross country cruise or high speed autobahn I could be perfectly happy with a bit more revs at cruise in 5th if it meant better-er ax all the other times I'm just driving around and going up hills.

Still though, if the subject is more oomph compression and a non-emissions cam ---and of course a decent exhaust (that's a foundation for everything really, and so it goes without saying but probably should be said anyway) is at some point the absolute key thing..
 
...

Easiest answer is:
1)pull the head, and have a mchine shop chop about 060" or 1.5mm off

...

Agreed. Three additional points.

1. VX Cam from IPD
2. Base timing 14? BTDC
3. Open up the exhaust. 2 1/4" pipe minimum.
 
One last point (since what I have proposed has caused me monetary loss).

Shaving the head sixty thousandths and dropping in a VX cam effectively makes the engine interference.

You have been made privy. Now, go have fun ;-) (and make sure your tensioner is new AND tight)
 
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