intake manifold design

[deaf_rattle]

I am thinking about going front facing intake manifold on my 7mgte.
Alot of people dont bother getting their modified manifolds flow tested.

is getting it flow tested essential? or are there calculations or designs you can use without the need for flow testing?

Cheers

[CelicaGT8]

essential? no.

But i wonder how much it cost....

[cat007]

For forced induction flow testing and then adjusting to suit, isn't so important

[xsspeed]

I would say more important for NA, but probably still beneficial for FI motors.

There are oldschool ways to flow test a head using vacuum cleaners apparently, so you may be able to rig something up and test yourself?

It was mentioned over on oldschool in the twincam head design thread.

[mjrstar]

suggest that it depends if other flow increasing mod have been done, with the 1g i have extensive head work reaps very little benifit as the valves are too small to flow more, wheras if you put some bigger cams in then yes you do need manifold work.

[QikStarlie]

make all the runners the same and your half way there. the way the air enters the plenum and plenum design will effect the flow to each runner.

[deaf_rattle]

the reason for doing this is to tidy things up in the engine bay
shorten i/c piping
i/c doesnt have to run over the engine.

the 7mgte manifold is 2 part, runners and then manifold. so would probably run the runners then new manifold

[the fallen303]

why not do similar to what suze did and got a 1jz plenum grafted onto the runners of her 7m?

other than the obvious giving you shit cause you've got 1jz stuff on your 7m, could be something to look into? one drawback of front facing plenums is if the plenum is equal size right from front to back is the back cylinders can get a bit on the rich side due to not as much air? so i've heard...

[blackmk3]

^ That looks ugly having 1j parts on a 7M, easy to make your self, well i did and i aint no welder or engineer, biggest issue was bonnet clearance. I just made sure when making it that all the openings into the manifold were all of equal size, runner length is the same for all. Been on there for around 30,000kms now and all spark plugs are the same color

I PM'D you some pics of my build a while back Matt

But in general its the best thing i ever did, clears up the engine bay, spark plugs are easily accessible, intercooler pipes are easy

I have a MA70 however

Nick

[deaf_rattle]

Hey Nick

Thats right, you still got the pics?


Just been looking into the jz swap John, but apparantly its not the best for flow due to the ports not matching up or something.

id like to keep the alternator in place, which will make things slightly more difficult, but im able to relocate the fuse box, which will give some more space.

[postfach]

This is a perfect excuse to get ITB's