Tunnel port advice

[blykins]

To be fair here, Randy and I have been talking for at least 2-3 months about this build and his initial horsepower requirements started out in the 700-800 hp range.  After discussing it with him and pointing out the relationships between factory blocks, displacement, tunnel port head intake port sizes, rear end gears, and the like, we approached it with a 482 build and around 600 hp.  I also added that if he really felt he needed the horsepower, the heads and intake could be modified and it would certainly help the horsepower, adding about 80-100 from past experiences. 

I'm certainly not against using the factory crankshaft but we are back at looking at horsepower goals and streetability.   Under no circumstances would I reuse those factory rods though, no matter how much they've been polished or loved on. 

If you're curious as to how much horsepower a 427 would make in streetable trim, a 465 will make about 600 with a solid camshaft and unported heads/intake, going up to 7000 rpm.   You're looking at around 525-550 hp with the 427 depending on the compression ratio and rpm range. 

I do believe that there can be too many experts in the room at one time, so I'll leave this post and make my way back out to the shop. 

[JamesonRacing]

Does it really gain you anything to port tunnel port heads?

I vote number 1.

I think it's tricky to get more intake port flow without killing velocity, but the exhaust ports on the tunnel port heads are pretty awful.  With some cautious porting on the exhaust, we were able to get them flowing a little bit better than as-cast Edelbrocks.

[blykins]

Does it really gain you anything to port tunnel port heads?

I vote number 1.

I think it's tricky to get more intake port flow without killing velocity, but the exhaust ports on the tunnel port heads are pretty awful.  With some cautious porting on the exhaust, we were able to get them flowing a little bit better than as-cast Edelbrocks.

The exhaust ports do stink, but they work.  The intake ports benefit from raising the floors.  It decreases the port volume (in the 60's, bigger was better), increases flow, and increases velocity.   Most of the TP heads that we have ported flow around 380 cfm with a smaller port than factory. 

[fastf67]

Great to have you here.
I've built and worked on alot of rides and that's a tough question. LOL it really is, sounds like your off to a good start. To find the best answer you need to start with,
First: What really is your honest intentions with your ride. Street, Street/strip, road course or all out hard racing. Without us knowing that in some depth no one can tell you whats best to do with what you have, or open opinions also can be called to many cooks in the kitchen and different brain waves will just throw you off track of your goals.
Second: You have talked to Bret in depth apparently so he knows and understands whats needed and would never steer anyone wrong. He's one of the top of the shrinking number of fe builders.
Third: Write down on paper if need be with a game plan and don't steer off coarse of it. YES in asking for advice and how-to's and be very specific. There's so many knowledgeable people here that live and breathe fe and will very happy to help. That's whats great about this site over others.
Forth: You will enjoy your finished product or ride. Hard work pays.

That's what I learned after flip flopping around my first build 30 years ago and the best answer i got for now.  Mike

[Katz427]

I have same project, old 427 tunnel port, bought at auction. The block was beat, (6 sleeves) and I decided to get a BBM block. My reason for keeping it a tunnel port is nostalgia, the engine came from a sportsman roundy-round car, that I remembered and a driver ( Maynard Troyer). If I wasn't tied to the nostalgia, I would build a 427/482 with Blair's pro-ports. A nice project, you have! Good luck!

[hhiibel]

sell it. it belongs in a cobra. build a max effort bear block.

[1966lanetp]

Great to have you here.
I've built and worked on alot of rides and that's a tough question. LOL it really is, sounds like your off to a good start. To find the best answer you need to start with,
First: What really is your honest intentions with your ride. Street, Street/strip, road course or all out hard racing. Without us knowing that in some depth no one can tell you whats best to do with what you have, or open opinions also can be called to many cooks in the kitchen and different brain waves will just throw you off track of your goals.
Second: You have talked to Bret in depth apparently so he knows and understands whats needed and would never steer anyone wrong. He's one of the top of the shrinking number of fe builders.
Third: Write down on paper if need be with a game plan and don't steer off coarse of it. YES in asking for advice and how-to's and be very specific. There's so many knowledgeable people here that live and breathe fe and will very happy to help. That's whats great about this site over others.
Forth: You will enjoy your finished product or ride. Hard work pays.

That's what I learned after flip flopping around my first build 30 years ago and the best answer i got for now.  Mike
[/quote

Basically my Fairlane is a toy. It’s a pretty nice mid price car, it has  no A/C, heater, PS, Power brakes nor radio. It gets driven about 100 to 150 miles a year so I don’t mind buying racing fuel if needed. I may go to the track (drag) a few times, but I don’t want to build a race car.

[1968galaxie]

The exhaust ports do stink, but they work.  The intake ports benefit from raising the floors.  It decreases the port volume (in the 60's, bigger was better), increases flow, and increases velocity.   Most of the TP heads that we have ported flow around 380 cfm with a smaller port than factory.

What work is going to be done with the factory TP intake manifold?
The cylinder head may flow 380 cfm - but what happens when intake is attached?
The combination of cylinder head and intake manifold are what makes power - or not.

I am sure Brent has flowed the TP head (ported) with the intake.
Hopefully he can shed some light on the question.
I have forever wondered how much the TP manifold affects the cylinder head - never having had the opportunity to flow a TP combo.


Cheers

[blykins]

The same work has to be done to the intake....floors raised, plenums shaped, etc.  Obviously the intake manifold loses some flow due to the pushrod tubes being in the way, but the combinations are still very stout.   

[67xr7cat]

Basically my Fairlane is a toy. It’s a pretty nice mid price car, it has  no A/C, heater, PS, Power brakes nor radio. It gets driven about 100 to 150 miles a year so I don’t mind buying racing fuel if needed. I may go to the track (drag) a few times, but I don’t want to build a race car.

Given the description of the car and its use I'd say do #1 and just make upgrades for durability like good valves, valvetrain, a good set of rods, etc... Value here seems to be it is a 427 SO tunnel port so enjoy the vintage experience.

[wowens]

In 1973 to 1975 my "only car" was a 67 Mustang fastback, 427 Tunnelport, two matched HM prepped carbs, HM 882 grind cam and dykes ring pistons. Heads and intake were unmolested.
If you can stand very bad street manners, keep it. Mine was a slug below 3500 and herky jerky around town. 3500 rpm to 7300 it was a bad ash ride.
Was my favorite.

[1966lanetp]

Given the description of the car and its use I'd say do #1 and just make upgrades for durability like good valves, valvetrain, a good set of rods, etc... Value here seems to be it is a 427 SO tunnel port so enjoy the vintage experience.
[/quote]

Well I know I’m going with new rods and pistons so I see no reason not to stroke it and get a new crank also. I’ll sell the original rotating assembly to someone who wants vintage ford factory HP parts. A stroked engine should help with the heads, I’ve been told. Thanks for your advice.

[1966lanetp]

In 1973 to 1975 my "only car" was a 67 Mustang fastback, 427 Tunnelport, two matched HM prepped carbs, HM 882 grind cam and dykes ring pistons. Heads and intake were unmolested.
If you can stand very bad street manners, keep it. Mine was a slug below 3500 and herky jerky around town. 3500 rpm to 7300 it was a bad ash ride.
Was my favorite.

[/color]

That sounds like a great ride, was it a 4 speed? What gears? Do you think lower gears would’ve helped? Thanks

[My427stang]

In 1973 to 1975 my "only car" was a 67 Mustang fastback, 427 Tunnelport, two matched HM prepped carbs, HM 882 grind cam and dykes ring pistons. Heads and intake were unmolested.
If you can stand very bad street manners, keep it. Mine was a slug below 3500 and herky jerky around town. 3500 rpm to 7300 it was a bad ash ride.
Was my favorite.

[/color]

That sounds like a great ride, was it a 4 speed? What gears? Do you think lower gears would’ve helped? Thanks

I bet it would help! 90 degrees of overlap is stout with the HM Lemans cam.  Fun, but better cams out there today to keep that intake moving

[Leny Mason]

Given the description of the car and its use I'd say do #1 and just make upgrades for durability like good valves, valvetrain, a good set of rods, etc... Value here seems to be it is a 427 SO tunnel port so enjoy the vintage experience.

Well I know I’m going with new rods and pistons so I see no reason not to stroke it and get a new crank also. I’ll sell the original rotating assembly to someone who wants vintage ford factory HP parts. A stroked engine should help with the heads, I’ve been told. Thanks for your advice.
[/quote]
I am trying to buy My old one back, is had a little low end but not much but it was like a two stroke when it hit the RPM it liked away you went, I would stroke it a lot I think that is what would help it a lot, and play with the heads and intake, if I were You I would have Bret or Blair do it they have a lot of experience. Leny Mason