Fonz69

I am putting my 540 dart motor in the 69 conv. and was wondering if anyone has tried dart pro1 heads in a vette using the side mount headers from hooker?

My concern is with the exhaust port height on the heads and if there will be any clearance issues?

Any help would be great, I e-mailed Dart to see what the height diference is if any at all and am waiting a reply.

69ttop502

I had issues with my AFR 315's. The port is only raised .375 but I had to cut and reweld 4 tubes. Having said that, it seems as if every car is different so you may get lucky depending on how raised the Dart port is.

Fonz69

right thats what brought up my worries, a friend of mine has a set of afr's on his boat and mentioned of the height difference.

I sure hope I do not have to start hacking away on a $1800 exhaust system

I wonder if I could have Hooker adjust them there and then jet hot coat them?

Probably would cost a fortune though

63mako

Which Dart Head is it? Part #s would help. Their website will probably let you know if it is a raised port and by how much.

Fonz69

I checked there website and it says they are raised port but not how much.

I e-mailed Dart tech line to see what they say.

They are the Dart Pro1 aluminum 325 heads not sure on the part number though

HABIT

Maybe these heads with the .300 raised ports ???



DART PRO1 ALUMINUM BIG BLOCK CHEVY HEAD

325 CC Assembled Complete PN# 19200116

BB-Chevy Pro-1 Cylinder Head

325cc Intake Ports
119cc Combustion Chambers
2.25'' Int/1.88'' Exh
1.625'' Springs, 250lbs @ 2.000''
.790'' Max Lift
Sold Individually

Specifications

Combustion Chambers: 119cc
Intake Valve Dia.: 2.250''
Intake Port Volume: 325cc
Intake Port Dim.: 1.700'' x 2.430''
Intake Port Location: Stock
Intake Gasket: 720-121
Exhaust Valve Dia.: 1.880''
Exhaust Port Volume: 129cc
Exhaust Port Dim: 1.650'' x 1.800''
Exhaust Port Location: Raised .300'', Standard Bolt Pattern
Exhaust Gasket: 375-1412
Exhaust Bolts: 1'' longer than stock (4)
Intake Flow: 397 cfm @ .800 lift / 28''
Exhaust Flow: 266 cfm @ .800'' lift / 28''
Head Bolts/Studs: ARP 070-135-3603 (Bolts)/ ARP 070-235-4103 (Studs)
Manifold: Rectangle Port (opening - 1.575'' x 2.250'') 6.25'' Tall
Milling: Min. 108cc (.005'' = 1cc) Flat Mill Only
Pistons: Most aftermarket pistons
Pushrod Length: Avg. +.200'' / +.250'', should always measure, stock length Int.=8.275'' / Exh.=9.250''
Pushrod Guide Plate: Comp Cams 249-4806-8
Retainers: 1.625'' - Titanium / 1.550'' Moly-steel (10°)
Spark Plug: .750'' reach, gasket-seat
Spring Cups: 1.625'' - .035 cup / 1.550'' ID locator
Spring Pockets: 1.740'' OD for 1.625'' cup (.030'' deeper max)
Springs: 1.625'' = 250lb @ 2.000'' / .790'' max Vasco-Jet H-11
Stud Girdle: Must use Dart design, 301-64110001
Valve Angles: Int - 24°, Exh - 15° (Rolled 2°) 4° cant
Valve Stem Dia.: .3415'' - 11/32''
Valve Train: Standard BB-Chevy 7/16'' Stud Mount
Valve Guides: 1/2'' OD Mag-Bronze cut for .530'' PC seals (.002'' press)
Valve Guide Length: Int - 2.100'', Exh - 2.250''
Valve Guide Clearance: .0014'' - .0021'' (with 11/32'' valve stem)
Valve Guide Spacing: Exh moved .045'' away from Int
Valve Seats: Ductile Iron, .006'' press (TIR .004'')
Valve Seat Angles: Int = 32° - 45° - 60° - 70°, Exh - 37° - 45° - radius
Valve Covers: 301-68000020
Torque: Head Bolts = 7ft/lb; Rocker Studs = 45ft/lb; Manifold = 35ft/lb
Block: Mark IV, Gen V, Gen VI with proper head gasket
Weight: 29lbs

Fonz69

Ok so they are raised 5/16"

I have never seen any of these header systems installed, how tight are they?

anyone have some pics of there's in the area's where they might hit?

69ttop502

My areas of interference were at the steering box and where they went under the chassis.

Bill