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289 mods

  • Thread starter Thread starter mcbride66coupe
  • Start date Start date Sep 18, 2004

mcbride66coupe

New Member
Sep 18, 2004
29
0
0
Wahiawa, Hawaii
Sep 18, 2004
#1
  • Sep 18, 2004
  • #1
can anyone tell me the easiest way to get my stock 289 up to 300hp-350hp? I just bought the car and im trying to decide how much i can do to the engine money wise before i start on the cosmetic side. thanks
 

jst6

Founding Member
Jan 9, 2002
152
0
0
Tucson, AZ
Sep 19, 2004
#2
  • Sep 19, 2004
  • #2
aluminum heads, new cam, intake, 650 carb, tri-y's and mandrel exhaust. should make 300 np. want more? just add a 150 shot on top.
 

mcbride66coupe

New Member
Sep 18, 2004
29
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0
Wahiawa, Hawaii
Sep 19, 2004
#3
  • Sep 19, 2004
  • #3
thanks for the tips, what are tri-y's?
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Sep 19, 2004
#4
  • Sep 19, 2004
  • #4
I'd agree with eveything above except for the heads and mandrel bent exhaust. Shelby did 306 hp with the Hi-po 289 with stock heads. just with the "Cobra" high rise intake, 715 Holly carb, and tri-y's. Your 289 has basically the same parts , performance wise as the hi-po motor had most of the difference between the hi-po and std 289's was in durability upgrades, not the basic parts. They had better rods, screw in studs w/guide plates, slightly better cranks. The cam was a hotter solid lifter grind, pistons were the same, the head's ports/valves/chambers were the same, intake manifold was the same. There are other minor differences too, but all in all there's no reason you can't upgrade your's to 300-350 hp with stock heads. As for mandrel bent exhaust, you'd have to dyno it over a std bent system to see the difference. Not enough there to justify the extra expense in my opinion.
 

66P51GT

New Member
Nov 7, 2003
721
1
0
Cerritos, CA
Sep 19, 2004
#5
  • Sep 19, 2004
  • #5
Tri'y's are a type of exhaust header. There are three basic designs for the 289.

1: Stock Cast Iron Exhaust Manifolds
2: 4 into 1 headers
3: Tri-y's





1. Stock cast ireons are just that. Stock or mildly modified engines.

2. 4 into 1's have all exhaust pipes connect together at the collecter. These are typically used for high horsepower engines.

3. Tri-y's connect the 1-3 and 2-4 (4-6 and 5-8) before the collector. These are better for low end torque. You will lose a bit of high end HP with this type of header but is best suited for street use.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Sep 19, 2004
#6
  • Sep 19, 2004
  • #6
66P51GT said:
You will lose a bit of high end HP with this type of header but is best suited for street use.
Click to expand...
Not that you'd notice I'm running them on the 331 stroker motor ( Canfield heads/Z303 roller cam/factory 3x2 intake and carbs) which puts out about 450 hp, in my 89 Ranger. So far I've only pushed the motor to 6000 rpms ( only a week old) but also ran them on a previous 400hp 5.0 with the same Canfield heads and it pulled to 7500 rpms with them. I think too many underestimate them for high hp/rpm motors. After running these, I'd never go back to 4 into 1's, there's just not a big enough difference to warrant the extra problems 4 into 1's cause.
 

mcbride66coupe

New Member
Sep 18, 2004
29
0
0
Wahiawa, Hawaii
Sep 19, 2004
#7
  • Sep 19, 2004
  • #7
so i looked and found this intake.....

EDELBROCK VICTOR JR. MANIFOLDS
VICTOR JR. 302 (3500-8000 RPM)
Designed for Ford 289/302 competition engines using stock cast iron or aftermarket Windsor-style cylinder heads such as Edelbrock heads #6025, #7716 and #7721, TFS, AR or equivalent. The Victor Jr. #2921 has no rear water crossover. Port exit size at cylinder head is 1.90" x 1.08" with enough extra material to open it up to 2.10" x 1.25".

i havent found a site to buy the high rise cobra intake does anyone know?

these tri-y's

Part Number : D689YS
Year : 1964-70
Cubic Inches : 260-289-302
Critical Installation
Requirements* :
· Under the chassis exit
· Y indicates Tri-Y design
· Stick only
· Will not fit column shift
· Console shift only
· May require power steering bracket

Tube Diameter : 1-5/8"
Collector Size : 2-1/2"
Port Shape : SAP
Price : $535.00

i also need a good website to find 715 holley carb, and advice on a cam. I dont want a cam that is gonna drain my gas though because i plan on this being my daily driver.

thanks
 

mcbride66coupe

New Member
Sep 18, 2004
29
0
0
Wahiawa, Hawaii
Sep 19, 2004
#8
  • Sep 19, 2004
  • #8
i found this carb....good or bad?

___________________________________________



Holley Double Pumper 750 cfm
750 CFM Four Barrel
Model 4150


* Double pump
* Mechanical secondaries
* Center hung float bowls
* Manual choke
* Power valve blow-out protection
* Four-corner idle system



HOL.0-4779C
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Sep 19, 2004
#9
  • Sep 19, 2004
  • #9
Too much intake, too much carb. If you want a good intake for your 289, pick from the Edelbrock Performer RPM, RPM air gap, Ford Racing A321 ( same as the old Cobra high rise) or Weiand Stealth. All are available thru Summit Racing.com . You also need to go with a 600 cfm carb, 650 at most. Nothing larger. Holley list 1850 for an automatic trans car, or a 4776 or 4777 mech. secondary for a 3 or 4 speed car. I'd personally shoot for the 4776 for a 289/4speed car.
 

mcbride66coupe

New Member
Sep 18, 2004
29
0
0
Wahiawa, Hawaii
Sep 19, 2004
#10
  • Sep 19, 2004
  • #10
what do you think about this combo? good or bad?

Edelbrock Intake: #EDL-7121
Edelbrock Performer RPM; Non-EGR; Also Stock Replacement/Street Legal part for Shelby Mustangs w/289ci.

speed demon
#1282010V: 650cfm Vac. Second

is this a good combo? or should i stick with holley 650cfm?
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Sep 19, 2004
#11
  • Sep 19, 2004
  • #11
That's a good choice, but I've read that the Demon carbs are rated a little different than Holley's and that 650 cfm rating is actually misleading in comparing it to a Holley. The Demon's are actually larger in cfms than Holley's even though the cfm is the same, but then again on a vacuum secondary carb, you can tune the secondaries to suit the motor's needs, so as to prevent over carbing it. That way the secondaries will only open up only as far as what the engine needs. A double pumper or mechanical secondary carb is different, when you floor the pedal, the carb opens all four barrels all the way, this will over carb an engine if the carb's cfm rating is too big for the engine's needs.
 
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