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How much horsepower is speed density capable of?

  • Thread starter Thread starter 87TTopGT
  • Start date Start date Dec 25, 2003
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87TTopGT

New Member
Dec 21, 2003
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Dec 25, 2003
#1
  • Dec 25, 2003
  • #1
I am just beginning to restore (and improve!) my 87 GT, I am the original owner and at present it is bone stock with the exception of a K&N air filter, a deleted fenderwell silencer, Centerforce Dual-Friction clutch, Steeda quadrant and adjuster kit, and Triax shifter. Of course, I ordered it with every option it was possible to get except leather seats, including the 3.08 gears in place of the 2.73's. I had to wait three months for the T-Tops, and three more for the Premium Sound package! (Ford said it was pre-empted by the Lincolns until they could ramp up production- jerks!) I have been driving a company car since 1995, and haven't put 100 miles on it since then. I know, I know, family kids bills etc.
My question is, how much horsepower can you get out of a speed-density 5.0 before you have to install the mass-air conversion kit? That's a chunk of change, I'd like to put on as many bolt-ons as possible before I fork over $500 to FRPP! Any former speed-density guys (oops- or gals!) out there with experience in this?

P.S.-Steeda Competition springs and Flowmaster 3-chambers are next in January- can't wait!

P.P.S.-Anybody like BBK equal-length shorties?
 

MadMatt5oh

Member
Jan 10, 2003
441
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16
St Paul, MN
Dec 25, 2003
#2
  • Dec 25, 2003
  • #2
I heard that stock for stock SD are faster- but of course that doesnt help your question
 

88stangmangt

Active Member
Nov 25, 2003
2,332
1
48
Stafford,VA
Dec 25, 2003
#3
  • Dec 25, 2003
  • #3
i found the conversion from summit for 300 (ford parts)gonna do it soon more precise and accurate. allows for bigger cam options too.
 

87TTopGT

New Member
Dec 21, 2003
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Dec 25, 2003
#4
  • Dec 25, 2003
  • #4
88stangmangt said:
i found the conversion from summit for 300 (ford parts)gonna do it soon more precise and accurate. allows for bigger cam options too.
Click to expand...

Wow, that's as cheap as buying it piece at a time on Ebay and I bet it comes with MUCH better instructions!
 

87TTopGT

New Member
Dec 21, 2003
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Dec 25, 2003
#5
  • Dec 25, 2003
  • #5
MadMatt5oh said:
I heard that stock for stock SD are faster- but of course that doesnt help your question
Click to expand...

Actually I heard that too.
 

Deths91Gt

Founding Member
Sep 30, 1998
1,394
3
39
KS
Dec 25, 2003
#6
  • Dec 25, 2003
  • #6
Theres alot of SD guys in 50tech.com. I guess other then the camshaft duration--you cant run more then 220 degress at .050 and tighter then 114 Ls. You can do anything to a SD car--You can run a blower but a small one like a SC trim or a Novi1000- I'm guessing prob no more injectors then a 24 maybe a 30 lb? but they run SD as a challenge--most guys just swap to MAF anyways.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
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Massachusetts
Dec 25, 2003
#7
  • Dec 25, 2003
  • #7
87TTopGT said:
Wow, that's as cheap as buying it piece at a time on Ebay and I bet it comes with MUCH better instructions!
Click to expand...

I paid $130 for my mass air conversion

$75 for computer

$35 for the ebay conversion harness (excellent directions btw)

$15 for stock mass air meter

$5 for air tube hoses


I have yet to install it. I have a mild list of mods and my car still runs perfect with SD. No need for it yet
 

Deths91Gt

Founding Member
Sep 30, 1998
1,394
3
39
KS
Dec 25, 2003
#8
  • Dec 25, 2003
  • #8
Mustang5L5 said:
I paid $130 for my mass air conversion

$75 for computer

$35 for the ebay conversion harness (excellent directions btw)

$15 for stock mass air meter

$5 for air tube hoses


I have yet to install it. I have a mild list of mods and my car still runs perfect with SD. No need for it yet
Click to expand...

I'm curious--what are your mods??
 

87TTopGT

New Member
Dec 21, 2003
173
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Dec 25, 2003
#9
  • Dec 25, 2003
  • #9
Mustang5L5 said:
I paid $130 for my mass air conversion

$75 for computer

$35 for the ebay conversion harness (excellent directions btw)

$15 for stock mass air meter

$5 for air tube hoses


I have yet to install it. I have a mild list of mods and my car still runs perfect with SD. No need for it yet
Click to expand...

Man, where did you get such a clean interior? Wish mine still looked like that...


P.S.- Your mods link is dead
 

BigDaddyCee

Founding Member
Jan 1, 2000
1,404
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0
Canada
Dec 26, 2003
#10
  • Dec 26, 2003
  • #10
I would say that one of the biggest bangs you would get for your buck would be to get a free-er flowing exhaust starting at the headers all the way back. Then to get some new gears 3.55's or 3.73's this wouldn't affect speed density at all and would be a good start at waking up your stang.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Dec 26, 2003
#11
  • Dec 26, 2003
  • #11
87TTopGT said:
P.S.- Your mods link is dead
Click to expand...


SHould be up now, but it's a little out of date.

Here are my engine related mods.

Cobra Intake w/ 1/2" phenolic spacer
65mm Throttle Body
BBK shorty Headers
Off-road H-pipe
Mac cat-back
BBK fenderwell cold air
underdrive pulleys
adjustable fuel pressure regulator
1.7 cobra roller rockers
electric fan
180* thermostat, new plugs wires, coil all those little things 14 degrees timing

I pretty much have the major bolt ons short of heads and cam. I plan on putting on some Gt-40P's and am pretty confident the SD setup will work with them. I also hear that the Trick Flow Stage 1 cam will work well with SD. I have this cam in my '85 motor, but may pick up another and see how it works with SD.

If i need mass air then, i have the conversion ready, but right now the idle is rock solid and it runs perfectly.
 

stock50LX

Curmudgeon
Founding Member
Oct 2, 2001
1,858
0
0
University Place, WA
Dec 26, 2003
#12
  • Dec 26, 2003
  • #12
Save your money. Stay with SD until you get many many mods. You can change intake, TB, heads, etc. Be careful with cam selection as you must maintain vacuum for you SD to work correctly. Your limitations are not really severe ones. I planned to change immediately too. Now I don't even consider it.
 

bmorrisj

Member
Sep 26, 2003
449
0
17
Buena Park, CA
Dec 26, 2003
#13
  • Dec 26, 2003
  • #13
i just got my SD 87 GT in september....but only thing i have on is CAI, adj. fuel regulator, and some flowmaster 40's...and i just recently noticed i have eibach springs all around with kyb shocks, next thing will be an o/r x-pipe or h-pipe... with some shortie headers..... after that it is a must for me to go to mass air....
 
S

Schlodes

Founding Member
Feb 26, 2001
354
0
0
Lidsville.... West side dawg..
Dec 26, 2003
#14
  • Dec 26, 2003
  • #14
Back in 1996 I had a friend with an 87 GT he bought cheap. He was going to College at the time so $$ was limited... but we street raced every weekend back then... tons of cars used to come out.. Anyways, about mid summer he ended up buying a bunch of stuff from a guy who was going 351. Ended putting 4.10s, stock dart heads, 1.7 rockers, GT 40 upper and lower, 70 mm T body and a better fuel pump, shorty headers and stock H pipe with the cats still in place but no muffs or tails.. Everything else was still stock inlcuding camshaft, injectors and fuel regulator.

One night he called me over and says lets go for a ride.. [had no idea he did any of this.. cept for the 4.10s] his car had always sounded sorta loud & goofy due to always having had an open H pipe. It never really sounded much different. We get away from where everyone was gathered and go find a dead stretch of rd [windsor Ont.] and he slows down, downshifts into 2nd with a big smile and says "watch this" and just floors it... goes bananas spinning and smacks the limiter... he pwershifts 3rd and the car is going sideways spinning uncontrollably... finally it hooks after about 30 feet of spinning in 3rd and the tach just gone..., he smashes 4th and man did that thing pull!

He did take it to the track but on street tires and managed to get a 13.1 but went like 110-111 MPH LOL.,,.. this was in GT too not a light Coupe.. I don't rememebr it having any surging idle, or bad driveability issues, and the stock cam with 1.7s pullled hard right till it bumped the limiter. Thing was fast for what it had done.

I wouldn't hesitate to buy a SD car and leave it that way...
 
R

RickyB

New Member
Jan 17, 2002
592
0
0
NJ
Dec 26, 2003
#15
  • Dec 26, 2003
  • #15
t-tops are getting rarer everyday
 

88STANGCONVERT

Founding Member
Aug 27, 2001
622
0
0
TRI-CITIES, WASHINGTON
Dec 26, 2003
#16
  • Dec 26, 2003
  • #16
87TTOPGT,
I will be honest with you and tell you that I am not the best at SD, but I have SD on my car and at one time I planned to change it until I spoke with a guy here who is running a SD stang with some times that are just mind blowing. I am not sure what his stangnet name is but alot of guys know him as the SD guy. I think that he is over at 50Tech alot. If I were you I would jump on 50tech and ask the question or search for it on topics. You could search here also and you should find alot on this subject here and maybe you would find the Sd guy I am referring about. There is a cam that alot of SD guys use that is made by I think it is Crower that is about at the limits of what SD cams can be and the power they are making is awesome. I figure why spend $300.00 to 500.00 for Mass air, save the money for other modes. Before you make a decision I would research this first. I plan on not changing over and after the first of the year I will putting in a new 306 with a Tmoss ported lower intake and heads by Thumper. A respectable 300hp or so is all I am looking for and I feel that SD will work but I too will be more research on SD to make sure. I wish you luck in your research and if you find something out please let us know.
Good luck!
 
B

blk306

New Member
Jun 1, 2003
213
0
0
MD
Dec 26, 2003
#17
  • Dec 26, 2003
  • #17
I can't answer your question but a buddy of mine has a SD 88 GT with over 210,000 miles on it and he ran a 13.6@around 100. He has CAI, MSD coil, a VERY short belt, batt relo, O/R H pipe, Flow catback, 3.90s and ET streets.
 

87TTopGT

New Member
Dec 21, 2003
173
1
0
Dec 26, 2003
#18
  • Dec 26, 2003
  • #18
Mustang5L5 said:
SHould be up now, but it's a little out of date.

Here are my engine related mods.

Cobra Intake w/ 1/2" phenolic spacer
65mm Throttle Body
BBK shorty Headers
Off-road H-pipe
Mac cat-back
BBK fenderwell cold air
underdrive pulleys
adjustable fuel pressure regulator
1.7 cobra roller rockers
electric fan
180* thermostat, new plugs wires, coil all those little things 14 degrees timing

I pretty much have the major bolt ons short of heads and cam. I plan on putting on some Gt-40P's and am pretty confident the SD setup will work with them. I also hear that the Trick Flow Stage 1 cam will work well with SD. I have this cam in my '85 motor, but may pick up another and see how it works with SD.

If i need mass air then, i have the conversion ready, but right now the idle is rock solid and it runs perfectly.
Click to expand...

Hey Mike, love the Cobra rims- are they 8" or 9"? If 9" do you have any trouble with rubbing front or back, and what width tires do you run?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Dec 26, 2003
#19
  • Dec 26, 2003
  • #19
87TTopGT said:
Hey Mike, love the Cobra rims- are they 8" or 9"? If 9" do you have any trouble with rubbing front or back, and what width tires do you run?
Click to expand...

They are 17x8's. I run 235/45/17's up front and 245/45/17's out back. I can go wider out back, i am thinking of some Nitto DR's maybe 255's

I have had 17x9 cobra R rims with 255's on. Slight rub in the front but no prob out back
 

StangFireman

Founding Member
Jan 5, 2001
2,113
0
0
Lebanon, Pennsylvania
Dec 27, 2003
#20
  • Dec 27, 2003
  • #20
I'll be able to tell you more about SD very soon. I bought Bob Cosby's Factory Stock car and it has SD. He's run a best of 12.18@111 with a crappy 60ft of 1.78 All this with stock cam, stock E7 unported heads and a 1.72 rocker. After some suspension work, I'm hoping to get some 11's out of it. Oh yeah, a 4.56 gear on 275 DR's.
 
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