As title really.
It would be good if you said what porting you had too as that affects things.

Just trying to work a few things out, and to save on trial and error hopefully you guys can chime in with your results

Thankyou

 

iirc i have 16"hg at idle(my idle is 1200 rpm) and 22"hg decel.

my porting is a early opeing med size street port. IO at 24* and IC at 65*

 

large streetport. about 22"/550mm on decel. at idle it is between 275-325mm or 11-13" inches at 1000-1100rpm, depending on temperature and accessory load

 

I have BNR stage 3's on a street ported motor from MazMart in Atlanta, I pull ~ 16 -17 inches at idle (1000 to 1100 rpm). Engine has 6000 miles on it.

Sorry, This is from a FD ... misread the title.

Danny Gamble

 

IRP Stage 3 streetport of a new mazda crate engine approx 8k miles ago with 2mm RA Black/Super Seals..... -350 to -370mm at 1000 rpm idle, and -630 to -650 when letting off the throttle in 5th gear at around 3300 rpm.

 

Big half bridgeport with huge primaries 14"hg warm idle at 1500 rpm
timing at idle is 25*and split at 15* from 500 rpms up to 1500,it pulls mid 20"hg on decel and the motor has 1000 miles on oem seals.

 

hybrid 6 port turbo engine with late close mildport turbo center plate, LPG mixer
17 inch Hg at 1000-1100 rpm
will pull 25 inch Hg on decel

 

8 inches of vacuum at 1000 rpm very large street port

 

^
That's were my old 10th AE was. Those are typically very fun motors.

 

^^ do you have any issues with the booster and having that low of vacuum?

 

No, I did not.

 

Everything works fine

 

mine does 11 inhg @ 1550rpm idle on the autometer boost gauge but we installed a ems stinger and it read 5.5 vacuum. now i don't now which one to believe.

fresh rebuilt RA black superseal half bridge port engine, T61 turbo.

what is the vacuum suppose to be at?

still not tuned or dyno. will see what happens when i take it the tuner.

 

17-18 @ around 900-1000RPM
S4 turbo keg, street ported
So the haltech and guage tell me
Must not be a large port.

 

Its not about being large its about how early a port opens as to how much vacuum it pulls their are other factors involved but the above is one of the larger factors

 

Ports with big overlap tend to affect vacuum cause they open way early than a regular ported motor(bridges and big street ports)but you can gain a little more vacuum running more split at idle and a little more timing,i do have some brake booster issues if i drive the car cold.

 

anymore vacume #'s at 1k rpm?

whats is high and what is low?

 

I get 14''-15" vac. at 900rpm and it works up to 17'' if the idle goes up to 1,100. when I let off it and coast it goes past 25'', just depends on what rpm I am at.

Large Street Port- Single turbo-RA 2mm superseal (10,000 hard miles on them)- Atkins solid corner and cryo sideseals- Built by me.