• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Fox Phenolic spacer on Systemax intake. Are long tube headers worth it?

  • Thread starter Thread starter Brent Francis
  • Start date Start date Aug 20, 2023
B

Brent Francis

Member
Feb 19, 2019
48
5
18
Maryland
Aug 20, 2023
#1
  • Aug 20, 2023
  • #1
Hello, I have a ported Systemax 2 intake from Ed at Flow Tech ready to go on. Engine is a stock bottom end 1990, TW 170 heads, mild Crower cam with 1.7 rockers, powerdyne BD11A supercharger, 3.73 gears, T5. Current intake is Performer RPM 1 with 70mm BBK throttle body. When the Systemax goes on should I use a phenolic spacer? Should I change to a 75 or 80mm throttle body? Lastly is it worth changing from bbk shorty headers to bbk long tube headers? Thank you in advance
 

Bullitt347

I have been doing it wrong this whole time
15 Year Member
Mar 23, 2007
3,974
2,956
194
Middle of Maine
Aug 20, 2023
#2
  • Aug 20, 2023
  • #2
How much power/boost?
What is the rest of the exhaust system?
The spacer increases the runner length which will move torque down in the rpm range, maybe even increase torque slightly, but it will sacrifice higher rpm HP by a bit. WIth the S/C you may not notice either.
 
B

Brent Francis

Member
Feb 19, 2019
48
5
18
Maryland
Aug 20, 2023
#3
  • Aug 20, 2023
  • #3
Bullitt347 said:
How much power/boost?
What is the rest of the exhaust system?
The spacer increases the runner length which will move torque down in the rpm range, maybe even increase torque slightly, but it will sacrifice higher rpm HP by a bit. WIth the S/C you may not notice either.
Click to expand...
Boost is around 6-7. Rest of exhaust is 2.5 off road H pipe into Black Widow Venom 250 mufflers. Then 2.5 tailpipes to the bumper
 
B

Brent Francis

Member
Feb 19, 2019
48
5
18
Maryland
Aug 20, 2023
#4
  • Aug 20, 2023
  • #4
Brent Francis said:
Boost is around 6-7. Rest of exhaust is 2.5 off road H pipe into Black Widow Venom 250 mufflers. Then 2.5 tailpipes to the bump. 42 lb injectors
Click to expand...
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,302
1,645
214
Acworth, GA
Aug 20, 2023
#5
  • Aug 20, 2023
  • #5
That doesn't make any sense. Why are you putting a Systemax 2 intake much less a ported one on TF 170cc heads? Frist off I would ditch that intake and get like a Cobra intake or something. That thing is going to kill your intake velocity going into those little heads. Throttle body 65mm or bigger is fine. Always do the longtubes. Shorties suck the life out of these cars.

Kurt
 
Reactions: Noobz347

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,913
4,036
183
Claremore, OK
Aug 20, 2023
#6
  • Aug 20, 2023
  • #6
Did you work with Ed when you chose the intake and having him port it or did you buy it from someone else? I agree that intake let alone ported is overkill for those heads. Send you Edlebrocks to TMoss and that will help more than anything. 75mm TB is plenty for your setup.
 

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
8,485
8,708
234
S.I.NY
Aug 20, 2023
#7
  • Aug 20, 2023
  • #7
70 or a 75 is fine - the factory hole on the intake is a 75 .

I ran a stock systemax on a 170 TFS head with a blower for a long time and it the car ran great .

FWIW I made 728 to the tire with a 70mm tb . So 70 or 75 is more than enough on that bd11a .

Do you need the spacer ? No . But to clear the driver side VC a 3/8 - 1/2 spacer wouldn’t hurt . I’d go as thin as possible with a stock hood .

Headers - a set of BBK 1 3/4 LTs would do the trick .
 
Reactions: General karthief
B

Brent Francis

Member
Feb 19, 2019
48
5
18
Maryland
Aug 21, 2023
#8
  • Aug 21, 2023
  • #8
Good morning, thank you for your advise. I bought the intake from Ed when I was planning on getting a 363. Then economy tanked and kids in private school. I cancelled the 363 I had on order. I would consider selling the intake.
 

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
8,485
8,708
234
S.I.NY
Aug 21, 2023
#9
  • Aug 21, 2023
  • #9
Brent Francis said:
Good morning, thank you for your advice. I bought the intake from Ed when I was planning on getting a 363. Then economy tanked and kids in private school. I cancelled the 363 I had on order. I would consider selling the intake.
Click to expand...
Intake is fine forced induction
 
B

Brent Francis

Member
Feb 19, 2019
48
5
18
Maryland
Sep 4, 2023
#10
  • Sep 4, 2023
  • #10
TOOLOW91 said:
Intake is fine forced induction
Click to expand...
If I find a good set of used 15/8 ceramic BBK long tubes at a decent price do you recommend I pass on them and wait till a set of 13/4 ceramic coated come along? Happy Labor Day to everyone
 

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
8,485
8,708
234
S.I.NY
Sep 4, 2023
#11
  • Sep 4, 2023
  • #11
Brent Francis said:
If I find a good set of used 15/8 ceramic BBK long tubes at a decent price do you recommend I pass on them and wait till a set of 13/4 ceramic coated come along? Happy Labor Day to everyone
Click to expand...
I’d run the 1 3/4 stuff if it were me that’s what I ran in the past
 

bird_dog0347

still married haven't seen testicles in years
15 Year Member
Jun 7, 2012
2,301
2,037
174
Little Elm, TX
Sep 6, 2023
#12
  • Sep 6, 2023
  • #12
I never ran the BBK 1 3/4 but I have heard they fit better and are easier to install than the 1 5/8 headers I had on mine. Be prepared to fight them to get them installed but it's WAY easier if you have the heads off. If not, just skip the attempts to do it without disconnecting the motor mounts and jack the engine up, just jack it up a bit and get it over with and save the time.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,133
21,302
234
Box behind Walmart
Sep 6, 2023
#13
  • Sep 6, 2023
  • #13
revhead347 said:
That doesn't make any sense. Why are you putting a Systemax 2 intake much less a ported one on TF 170cc heads? Frist off I would ditch that intake and get like a Cobra intake or something. That thing is going to kill your intake velocity going into those little heads. Throttle body 65mm or bigger is fine. Always do the longtubes. Shorties suck the life out of these cars.

Kurt
Click to expand...

TOOLOW91 said:
Intake is fine forced induction
Click to expand...


I would install it and run it while keeping a casual eye on the market for an intake that is better suited. On a turbo car, we wouldn't be having the exhaust discussion but the big intake would still be an issue IMO.

The LT exhaust in my [brain dyno] says that the LTs will be worth 20+ HP and 10+ ft/lbs. When you get around to addressing the intake, I think you will notice a significant improvement in the car's performance at all power settings except for maybe WOT. The lazy air will be most noticeable when the hammer isn't fully planted and the blower is doing nothing.
 
Reactions: revhead347

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
8,485
8,708
234
S.I.NY
Sep 6, 2023
#14
  • Sep 6, 2023
  • #14
Noobz347 said:
I would install it and run it while keeping a casual eye on the market for an intake that is better suited. On a turbo car, we wouldn't be having the exhaust discussion but the big intake would still be an issue IMO.

The LT exhaust in my [brain dyno] says that the LTs will be worth 20+ HP and 10+ ft/lbs. When you get around to addressing the intake, I think you will notice a significant improvement in the car's performance at all power settings except for maybe WOT. The lazy air will be most noticeable when the hammer isn't fully planted and the blower is doing nothing.
Click to expand...
My combo drove totally fine with an a trim and that intake not ported with 170 heads and a 70 mm tb
The intake ports are the same as a gt40 port size untouched on the lower . His is ported but I doubt it’s crazy . They are not lazy one bit . With a blower he’ll have zero issue and to sell for a smaller intake isn’t wise in my
Opinion . If ed did the cam . It is spec in mind for all of this . If he thought intake was an issue he would’ve told him it’s an mis match

Once I ported to the 90 yes I noticed a slight and I mean slight difference just off tip in . Otherwise car drives the same
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,133
21,302
234
Box behind Walmart
Sep 6, 2023
#15
  • Sep 6, 2023
  • #15
TOOLOW91 said:
My combo drove totally fine with an a trim and that intake not ported with 170 heads and a 70 mm tb
The intake ports are the same as a gt40 port size untouched on the lower . His is ported but I doubt it’s crazy . They are not lazy one bit . With a blower he’ll have zero issue and to sell for a smaller intake isn’t wise in my
Opinion . If ed did the cam . It is spec in mind for all of this . If he thought intake was an issue he would’ve told him it’s an mis match

Once I ported to the 90 yes I noticed a slight and I mean slight difference just off tip in . Otherwise car drives the same
Click to expand...


...and my contention is that with another intake, it would be [better].
 

TOOLOW91

If you're the village idiot what's that make me?
20+ Year Stangneter
Nov 29, 1999
8,485
8,708
234
S.I.NY
Sep 7, 2023
#16
  • Sep 7, 2023
  • #16
Noobz347 said:
...and my contention is that with another intake, it would be [better].
Click to expand...
I think it will be out of breath . Rather quickly
 
Reactions: Noobz347

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,133
21,302
234
Box behind Walmart
Sep 7, 2023
#17
  • Sep 7, 2023
  • #17
TOOLOW91 said:
I think it will be out of breath . Rather quickly
Click to expand...

I know. That's why we have more than just one guy answering questions on Stangnet.
 
Reactions: TOOLOW91
You must log in or register to reply here.

Similar threads

Fox 329 HP low for a stroker?
  • Andresquintana.mma
  • Apr 15, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
23
Views
1K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Apr 19, 2025
Jarhead67
J
5
Hello Everyone !
  • 5150K
  • Jul 3, 2026
  • The Welcome Wagon
Replies
0
Views
83
The Welcome Wagon Jul 3, 2026
5150K
5
Exhaust 1 3/4” Long Tubes on a Fox Body AOD – Easiest route?
  • 5.0 Mike
  • Mar 19, 2025
  • Fox 5.0 Mustang Tech
Replies
6
Views
2K
Fox 5.0 Mustang Tech Mar 21, 2025
5.0 Mike
M
Engine Unexplainable Exhaust Pop and Gurgle
  • Mrnissen122
  • Feb 14, 2026
  • Fox 5.0 Mustang Tech
Replies
12
Views
577
Fox 5.0 Mustang Tech Feb 18, 2026
Noobz347
S
Requesting Guidance for 306 motor swap - Fuel? - SD? MAF?
  • So_Flo
  • Jul 26, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
32
Views
2K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jan 4, 2026
Mcmahst
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?