Opinions Needed -- Engine/Drivetrain Mods in 69 Mach

[Jefhuf 13]

All the recent talk about camshafts, EFI, T-5's and gear ratios have gotten me thinking. I've been thinking of doing all these upgrades for some time and have even begun collecting bits. Rather than steal someone else's thread I figured I should make my own.

 

Current setup is a 351W bored .020" with stock bottom end, Trick Flow 170 heads, Comp Cams XE262H flat tappet cam, 1.6 rockers, Eddy Performer intake, Holley 650cfm double pumper, Hooker Super Comp headers and Pertronix billet distributor. Have a Weiand Stealth manifold on the shelf. 4 speed toploader feeds stock 2.89 gears in 9".

 

Life has gotten in the way for the past ten years so the car has been neglected. I'm hoping to change that this winter cause I want to enjoy it again and my son is dying to ride in it (5 year old who calls it a race car)!

 

I'm leaning towards installing an EFI system like FITech (or similar) and plan to upgrade the rear end to include a TruTrac (currently open). I have a T-5 that I toyed with the idea of building up with an Astro kit and going with a 3.73 or 4.11 rear, otherwise I would probably go with a 3.25 behind the toploader. While playing with the engine I will be installing the Stealth manifold but was thinking of springing for a hydraulic roller cam as well.

 

First question is probably whether or not all this work will be worth it! The car will spend 80% of its time cruising around town/highway with the balance spent at club events including drag strips and "road courses". Please let me know which direction you would head and your experiences/parts you would use again or avoid.

 

Thanks!

[fordguy69 24]

IMHO, an overdrive transmission and the fuel injection have been the two most impactful things I have done to my ride.  Both dramatically increased the driveability and pleasure factor with the car.  I wouldn't trade either of them for anything else. 

[shaun071 62]

Lower diff gears will make the engine more responsive and the trutrac will let you put the power to the ground better than the single wheeler. That's where I would start. The gears you mentioned are a good choice. OD trans and efi are mods I'm planning for my coupe. I have a similar spec 351c and have an AOD, 9" rear with trutrac and 3.50 gears

[Jefhuf 13]

Yeah I like the idea of the easy starting and less tinkering of the EFI. Any reason the EFI would weigh in on my cam choice?

 

The only deterrent to the overdrive is the cost...part of why I'm planning to try to rebuild a T-5 myself!

[shaun071 62]

If you don't do a lot of long highway trips stick with the toploader. I had 3.25 gears with a c4 which ran at 2800rpm at 65mph. Fine for a couple of hours on the highway but on a 600 mile trip I did a couple of times a year it was a bit hard on the ears and the wallet! If I were you I'd do the gears/trutrac and efi first then see how you like it.

[Jefhuf 13]

Only downside to doing gears before deciding on the trans is how different a ratio I would look for. I could probably get by with a 3.50 and top loader but even that would be a little low for what I'd want with the T-5 if I swapped down the road

[1969_Mach1 333]

What Toploader do you have?  Close Ratio or Wide Ratio?  The close ratio Toploader has a much numerically lower first gear and needs a numerically higher ratio rear axle gear, 3.50, 3.70, 3.89, etc.  The wide ratio Toploader has a numerically higher first gear so is a little better suited for 3.00 and 3.25 rear axle ratios.  The axle ratios I list are just examples.  Hopefully, it's clear what I am trying to convey.

 

Fuel injection is less tolerant of valve overlap which is determined by the camshaft.  Overlap directly affects engine vacuum.  That is why you see camshafts listed specifically for fuel injection.  This might not be as critical with aftermarket throttle body fuel injection.  Current aftermarket throttle body fuel injection and older, 1980's OEM fuel injection are "Speed Density" type systems that use engine vacuum as an input to determine engine load.  Thus, today's aftermarket throttle body fuel injection systems, although I'm sure greatly improved, basically use 1980's OEM technology.

[Jefhuf 13]

I'm running a wide ratio...as you noted if I had the close ratio I would swap to a set of 3.73 or 3.89 and be happy when I pull the trigger on an overdrive.

 

Understood on the EFI - cam relationship as well. Probably worth asking FITech their opinion but I'm assuming they are essentially designing their system around carb setups as that is their target market!

[fordguy69 24]

I'm running a wide ratio...as you noted if I had the close ratio I would swap to a set of 3.73 or 3.89 and be happy when I pull the trigger on an overdrive.

Understood on the EFI - cam relationship as well. Probably worth asking FITech their opinion but I'm assuming they are essentially designing their system around carb setups as that is their target market!

The FITech software handles the cam issue very well. My cam makes less than 11" of vacuum and it handles it beautifly. There are 4 cam settings in the software that do their magic, I have mine set on 3 and there is one more setting for even bigger cams.

 

While a TBI might be seen as 80's tech, the hardware and software used in today's systems is not.

[ray1970 88]

Hell ya its worth it.

Do we need FI

Do we need 5speeds and lower gears

Do we need sup. upgrades

Do we need 4 wheel disk breaks

Do we need 550hp

Do we need to piss the wife off by working on are cars

when she thinks a bathroom redo would be a better use of time.(money)

 

The answer is.__NO_______

 

But it make the driving experience far better and sometimes safer with each one I do.

The car I got off the side of the road 39 years ago is not the same car I have today.

Its safer-faster and far more dependable .....

WAY MORE FUN TO DRIVE..

[Jefhuf 13]

Thanks Ray! For those that did a custom grind cam from Bullet (or similar), what did the cam cost if you don't mind sharing? Did you get matching lifters, rockers, etc from them or just go with off the shelf bits from a speed shop based on their recommendations?

 

Ps- love that there are so many guys just like me...I'm going to tell my wife I'm normal after all! ;)

[Jefhuf 13]

Still doing research but looking at going with something like a Comp Cams XR282RF. I know that I will be changing the associated parts (⎌lifters, pushrods, valve springs & hardware) but CC says the 1431-16 steel roller tip rocker that I currently have installed will work. Would you guys stick with them or better to spring for full roller units? I will be sticking with a 1.6 ratio as I wouldn't have clearance for lift beyond .550 per Trick Flow (I will verify with clay before final assembly)

[barnett468 418]

efi is a waste of money for the dollars invested if you are trying to make horsepower unless you use a used ford gt unit and get it ported.

 

i would use full rollers with that particular cam.

 

if you get a custom cam, i would call straub tech but that is a bit of overkill for your app.

 

i would use morel 5323 or limited travel 5327 lifters.

[1969_Mach1 333]

The only thing that bothers me with the aftermarket throttle body EFI systems is that they are based on early 1980's "Speed Density" technology.  Nothing to bad with that.  But they are marketed and priced like it's some new break through technology.  These "Speed Density" technology type systems were not used for very long and phased out in the mid 1980's for the more accurate and precise "Mass Air" technology.  I just don't know how many people are aware of that when purchasing these systems.

 

EFI does provide better drivability and cold start performance. But, I don't know that a motor will make more HP with EFI.  If it does, I'd think something was wrong with the carburetor it replaced. 

[Jefhuf 13]

I don't think EFI would affect my HP numbers in either direction...if I chose to go that direction it would be solely for the convenience of starting and drive ability as you mention

[Rsmach1 71]

As far as your rocker question I would ditch the the roller tip rockers and go with full rollers. IMHO it makes no sense to go roller cam with all the benefits and use pivot ball rockers.