13 replies to this topic

[G'Racy]

I have an MG Metro inlet manifold fitted to my 1988 998cc mini together with a maniflow lcb and exhaust, new carb needle and k&n filter, would the Maniflow HiFlow inlet be a better option or?

[G'Racy]

Should have mentioned this is all bolted onto a 12g295 cylinder head, standard valve sizes I believe.

[unburntfuelinthemorning]

The MG metro inlet manifold flows well but by virtue of having large ports.  Good for 1275s and up but less so for small bore motors due to low port velocity so on a 998 you'll have less low down torque than you would have with a manifold that is more suited. 

 

See what the others say about alternative manifolds.

[Turbo Phil]

Are we talking about the Maniflow alloy manifold ? If so it’s flows better than the MG manifold but iirc the ports are even bigger. So as described above, it would be even less suited to your 998.
I’ll have a look later for you as I have these manifolds and have run flowbench testing with both.


Phil.

[dyshipfakta]

I like the metros vac take off I don’t think you would really see any difference. Apart from a lighter wallet

[G'Racy]

Thanks for the responses, I’d consider both the alloy and steel options from maniflow if there was benefit in my application, bear in mind this is for road not track use.
I understand the points your making on velocity, Phil I’d be interested to see the test results you refer to if you get chance.
Does anyone know if the minspares version is basically the same animal or does this have better/worse characteristics?

[luismx123]

Also interested in this. Just got myself the Yellow bible but inlets like the minispares/minisport arn't tested. How do they compare to the older type manifolds? 
 

[G'Racy]

I notice on the Calver website he’s tested the MG Metro manifold at 96.5cfm, Minispares small port manifold at 108.1cfm, and states the higher the cfm figure the more power potential (although as stated above port velocity being a limiting factor).
I notice in the same article he refers to Howley and Titan manifolds, seen these on eBay every so often, anyone know the port sizes on these compared to the MG and Minispares?

[andyapanel]

There is a graph in Vizard comparing flow, tho some of the manifolds I have never seen-but it's an old book.

I have never been disappointed with the Minispares inlet manifold.

[Turbo Phil]

The higher the power output the more air is required to support that, but simply bolting on a manifold that flows the most isn’t necessarily the way to go. Poor port velocity will reduce VE and kill off performance. So while a 7000+rpm full monty 1380 may need big ports in order to flow sufficient air, your stage one 998 won’t.

Phil.

[G'Racy]

Yes I totally get that, I’m just trying to determine if there is a better option for my stage 1 998 than the MG manifold, I’m guessing not.

[Turbo Phil]

Yes. Minispares do a manifold with smaller ports, ideal for the 998.

Phil.

[G'Racy]

I believe you’re referring to C-AHT770 on Minispares website, thats the one I referred to above and tested by Calver at 108.1cfm compared to 96.5cfm for the MG, an increase of 12% and sized correctly for gas speed on a 998, unfortunately showing as out of stock at minute.
Thanks for your help and advice much appreciated.

[unburntfuelinthemorning]

I have been assured that the Minispares manifold will be back in stock in about a week.  (Here, have a pinch of salt.)