99' stock head maximum hp - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Engine Performance This section is for discussion on all engine building related questions.
Sponsored by:
Sponsored by:

Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 04-13-2015, 04:26 PM   #1
Newb
Thread Starter
 
Join Date: Dec 2008
Posts: 7
Total Cats: 0
Default 99' stock head maximum hp

Hello I have a 99 ' 1.8L miata with gt3076r and made 395 whp at 1.8 bar of boost (more pressure did not made any difference)! I have stock sized valves and head except from retainers and springs ! Also stock intake manifold and throttle body! I want to ask you if I will have any gains from bigger throttle body and a begi intake manifold at the same pressure and what the maximum horsepower anyone have made with stock oem 99' head (stock cams without any porting)
hatzi_dim is offline   Reply With Quote
Old 04-13-2015, 05:29 PM   #2
Senior Member
iTrader: (2)
 
Join Date: Nov 2007
Location: Saint Paul, MN
Posts: 1,296
Total Cats: 22
Default

You'll see gains with a bigger TB and better intake (there are threads on that very thing). You'll see significant gains from a port/polish, +1mm intake (and exh if you can afford it) and if you can afford them some springs, shim under bucket with high lift cams. It's all about that flow without sacrificing velocity. There are threads on porting the head but in essence, be careful. Too much will be way too much.

The SUB setup is required for high lift cams or you could spit out shims and grenade the head. That's essentially what I've gone with, except for the intake/tb. It should get rid of that knee in the torque at 6k and let me rev to 8k with plenty of torque. I hope at least..
Der_Idiot is offline   Reply With Quote
Old 04-13-2015, 09:48 PM   #3
Senior Member
iTrader: (1)
 
Join Date: Mar 2008
Location: Cromwell CT
Posts: 1,107
Total Cats: 48
Default

now i know there are a lot of variables here, but

my built 99 head (thats for sale) made 65whp more on 3 psi less boost on a gt3071r

just sayin
ctdrftna is offline   Reply With Quote
Old 04-13-2015, 10:45 PM   #4
Junior Member
 
guttedmiata's Avatar
 
Join Date: Sep 2012
Posts: 438
Total Cats: -3
Default

Quote:
Originally Posted by ctdrftna View Post
now i know there are a lot of variables here, but

my built 99 head (thats for sale) made 65whp more on 3 psi less boost on a gt3071r

just sayin
Been waiting for a comment along these lines. This one was WAY nicer than I expected.
guttedmiata is offline   Reply With Quote
Old 04-14-2015, 02:10 AM   #5
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,367
Total Cats: 1,331
Default

stock intake manifold = fail fail fail fail fail
Savington is online now   Reply With Quote
Old 04-14-2015, 02:34 AM   #6
Senior Member
iTrader: (2)
 
Join Date: Aug 2013
Location: Houston, TX
Posts: 598
Total Cats: 31
Default

Did someone say squaretop?
SchmoozerJoe is offline   Reply With Quote
Old 04-14-2015, 05:13 AM   #7
Newb
Thread Starter
 
Join Date: Dec 2008
Posts: 7
Total Cats: 0
Default

I know that a built head will make more power but mine is stock cams valves ! I want to make 30 whp with begi intake manifold and skunk 2 throttle body do you think it is possible or it will be a waste of money ?
hatzi_dim is offline   Reply With Quote
Old 04-14-2015, 05:55 AM   #8
Senior Member
iTrader: (1)
 
Join Date: Mar 2008
Location: Cromwell CT
Posts: 1,107
Total Cats: 48
Default

i also had a custom fabricated manifold and 75mm throttle body.

square top manifold or a skunk2 ultra street manifold welded to a mazda flange.

But still at those boost levels with that turbo and a built head you should be me making a lot more power ( depending on fuel, on C16 you should be around 480)
ctdrftna is offline   Reply With Quote
Old 04-14-2015, 06:39 AM   #9
Newb
Thread Starter
 
Join Date: Dec 2008
Posts: 7
Total Cats: 0
Default

With honda intake i must use honda throttle body and iac as well ? I have ms3 by reverant
hatzi_dim is offline   Reply With Quote
Old 04-14-2015, 09:31 AM   #10
Newb
 
Join Date: Apr 2014
Location: North wales UK
Posts: 40
Total Cats: 0
Default

Interesting reading, i'm just building my engine,and essentially im only changing my head to a fully ported (CNC Heads UK) 99 head with SUB lifters and supertech double valesprings,Supertech valves and Catcams high lift cams,but im still running my standard GTR turbo (VJ23) and inlet manifold.
I've no idea what it will make after its built,once its running its going on the Dyno to see what it can do. I was running 330BHP at the flywheel at 1.8 bar.
i'll post up the results here.
chrisgtx is offline   Reply With Quote
Old 04-14-2015, 10:28 AM   #11
Elite Member
iTrader: (5)
 
Join Date: Oct 2007
Location: Canton, Ga
Posts: 1,707
Total Cats: 19
Default

The stock 99 intake manifold is a piece of crap. I'd resolve that first personally before ripping into the head.
Stealth97 is offline   Reply With Quote
Old 04-14-2015, 01:04 PM   #12
Elite Member
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,519
Total Cats: 259
Default

I would be surprised if anyone made more power on a stock 99 head than me - which is 458whp.

I got my head at a junkyard. The only work was to was machine it flat. Stock valves, guides, springs, seals, stock 7200rpm limit. Unknown mileage on the head

edit: 1.8 bar of boost sounds about right, I was at 2 bar (29 psi)
soviet is offline   Reply With Quote
Old 04-14-2015, 03:34 PM   #13
Senior Member
iTrader: (1)
 
Join Date: Mar 2008
Location: Cromwell CT
Posts: 1,107
Total Cats: 48
Default

Soviet, what intake setup? This was with your EFR? Ops power seems low for the gt3076 compressor at 26psi. I had a built setup off the bat with nothing to compare to.
ctdrftna is offline   Reply With Quote
Old 04-14-2015, 03:39 PM   #14
Newb
 
Join Date: Apr 2014
Location: North wales UK
Posts: 40
Total Cats: 0
Default

My intake manifold is a stock familia GTR one. I should of added my car is a 4wd 323 GTX. Or familia/protege over there.
chrisgtx is offline   Reply With Quote
Old 04-14-2015, 06:24 PM   #15
Elite Member
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,519
Total Cats: 259
Default

Quote:
Originally Posted by ctdrftna View Post
Soviet, what intake setup? This was with your EFR? Ops power seems low for the gt3076 compressor at 26psi. I had a built setup off the bat with nothing to compare to.
With stock 99 manifold and stock throttle body I did 400whp on 93 gas using EFR6758 turbo at 26psi (https://www.miataturbo.net/dynos-tim...-6758-a-68914/)
With flat-top manifold and stock throttle body I did 458whp on E85 using EFR6758 turbo at 29psi (https://www.miataturbo.net/dynos-tim...et-fuel-75011/)
soviet is offline   Reply With Quote
Old 04-14-2015, 06:36 PM   #16
Supporting Vendor
iTrader: (10)
 
Reverant's Avatar
 
Join Date: Jun 2006
Location: Athens, Greece
Posts: 5,441
Total Cats: 198
Default

It looks like the square top added maybe 15whp and the rest was the E85? How much timing were you able to add with the E85?
Reverant is offline   Reply With Quote
Old 04-15-2015, 11:31 AM   #17
Elite Member
iTrader: (10)
 
soviet's Avatar
 
Join Date: Jan 2010
Location: VA
Posts: 3,519
Total Cats: 259
Default

Quote:
Originally Posted by Reverant View Post
It looks like the square top added maybe 15whp and the rest was the E85? How much timing were you able to add with the E85?
a lot of timing, at least 10*

disclaimer: it was on different dynos, but they were both calibrated dynojets.
soviet is offline   Reply With Quote
Old 04-16-2015, 02:47 AM   #18
Elite Member
iTrader: (2)
 
Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 8,782
Total Cats: 119
Default

Quote:
Originally Posted by Reverant View Post
How much timing were you able to add with the E85?
All of it.
Faeflora is offline   Reply With Quote
Old 04-16-2015, 03:10 AM   #19
I take big bites
iTrader: (1)
 
turbofan's Avatar
 
Join Date: Sep 2010
Location: Hurricane, UT
Posts: 6,926
Total Cats: 526
Default

Appropriate post, fae.
turbofan is offline   Reply With Quote
Old 04-21-2015, 02:46 AM   #20
Junior Member
iTrader: (6)
 
Join Date: Feb 2011
Posts: 421
Total Cats: 9
Default

Quote:
Originally Posted by Faeflora View Post
All of it.
Who the hell let this happen?
Twibs415 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 59 Today 09:00 PM
WTB MP62 (Hotside) (NB2) Rick02R WTB 3 01-03-2016 08:18 PM
Expected intake temps on the track? tazswing Race Prep 20 10-03-2015 12:04 PM
Going back to stock. Need some 1.6 parts. Trent WTB 2 10-01-2015 01:15 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 11:52 PM.