hello.
Iam Nick from Greece.

my setup is.
B16A engine.
cp pistons 9.0:1 cr 81,5mm
eagle rods
gtX3076r turbo
3" downpipe and entire exhaust
9200 rpm limit
edelbrock intake

i want to build a ramhorn manifold. the only specs i want to know to procceed to do it are the size of the ss tubes (inlet and outlet)
what size to use to have a street car with good midle-high range??

these fullrace ramhorn manifolds and doc race what size they used?

thanks a lot!

 

As far as I know everyone uses 1.5" schedule 10 or schedule 40 pipe... if you use metric units its a 48,3mm pipe with 2.8mm wall = schedule 10, 3,7mm wall = schedule 40.

Hope it helps.

 

why the world is sooo complicated??

inchess....mm.... my head. lol.what meaning has the word schedule...
ok give me a break.
i prefere the easy way.

is ok to use 48,3mm outside diameter with 43mm inlet diameter?

i want midle-high range power.

 

48,3mm outer diameter and 43mm inner diameter... it's 2.65mm wall, right? I think if it's welded really good it will be ok, but I would try to get 2,8mm wall or 3mm wall.

For midle-high range I would suggest long runners... top mount I think.

 

What???
i uninstall a topmount manifold with the same size tubes to
use a ramhorn to be better at midle...

am i wrong with this?

 

Ok, basicly:

Longer runners - wider powerband
Shorter runnners - narrower powerband

Larger diameter - higher rpm power
Smaller diameter - lower rpm power

I'm not sure, but IMO you should think about your power goal and turbocharger used, cause IMO that turbocharger is really big on 1.6 engine, and it is not a big surprise that you lack mid range power... I don't think that you can get good mid range using a turbocharger that is capable of 550hp+.

 

I understand.
ok i have a person that want the gtx3076 and he will give me the gtx3071r.
Ramhorn with gtx3071r is better for street use than topmount with gtx3071r . right? What do you think?

 

I would just stay with the top mount, the difference in spool time is fairly small but it's much more efficient.

 

In theory ramhorn should spool up faster, but I do think that top mount would give wide/better power curve delivering more power.

What is your power goal??? if it is only up to 500bhp, I would suggest changing your turbocharger to that gtx3071 and runing it on you top mount to check if you are satisfied then.

 

Just one notice... my topmount manifold is like doc race. without equal lenght.
my goal is 500 hp.

 

Then just change this gtx3076 for that gtx3071 and go from there!

 

i will give it a try before i build another manifold.

this gtx turbo are strange.the only thing i wanted is to gain 100 hp.

i was with gt3071r with b16 cams and a mini ramhorn manifold at 400hp@18 psi and the car was strong at midle-high range.

i update my setup to gtx3076r with itr b18c6 cams and topmount manifold and this setup gave me 430hp@20 psi. i loose 30 hp at midle and gain 30 hp more at high.

too small change..