FE Power Forums

FE Power Forums => Member Projects => Topic started by: 2VNTG68S on October 17, 2013, 08:19:38 PM

Title: 390 Build for '68 Mustang 'vert
Post by: 2VNTG68S on October 17, 2013, 08:19:38 PM

I 'm building a 390 for a '68 Mustang convertible project.  Wish I'd found this forum sooner!

Going with Edelbrock RPM heads and intake with a Holley 750 and a good set of headers.

Cam is from Scott @ Cam Research.  Specs as follows:

.226I / .234E duration
.540I / .560E lift
109 deg LS

Thoughts on what kind of HP/Torque this combo will make?

My goal was a very streetable engine with a nice little lope @ idle

Mission accomplished?

Title: Re: 390 Build for '68 Mustang 'vert
Post by: jayb on October 17, 2013, 08:42:04 PM

Looks pretty good to me.  What is your compression ratio?  And are you basing the number on measurements, or what the piston manufacturer says?  I'm gonna say 410-415 HP and 445 ft-lbs of torque if your compression ratio is well matched to the cam.

Title: Re: 390 Build for '68 Mustang 'vert
Post by: 2VNTG68S on October 17, 2013, 09:54:46 PM

Thanks for the quick reply Jay.

We should come in around 10:1

That is exactly what I was hoping for on HP/Torque. I was thinking 400/450 so I'll be a happy camper if that's what she puts out.

Craig

Title: Re: 390 Build for '68 Mustang 'vert
Post by: 2VNTG68S on March 16, 2014, 12:41:40 PM

An additional question about my engine spec (above). What is a good starting point on a timing curve for this setup?

Title: Re: 390 Build for '68 Mustang 'vert
Post by: ScotiaFE on March 16, 2014, 12:52:30 PM

I'd start at 12* initial and 36* total mechanical all in by about 2800 rpm.
You can fiddle around with the carb and vacuum gauge to get you best initial though.
This should get it running pretty good.

Title: Re: 390 Build for '68 Mustang 'vert
Post by: 2VNTG68S on April 12, 2015, 10:15:58 AM

Well I finally got my 68 vert on the road and put some miles on it.

Noticing a few things that I'm hoping I can get some help with

1. Off-idle stumble and hesitation when accelerating but idles well
2. Strong fuel odour
3. Bogs at full throttle
4. "Seat of the pants" power seems very weak given the engine spec

Timing is set per ScotiaFE's recommendation above.

I know this is going be timing and carb but wondering if there are some best practices for getting it running optimally.  Do I need to start with the timing curve?? I'm a bit rusty so go easy on me  ;)

Title: Re: 390 Build for '68 Mustang 'vert
Post by: 2VNTG68S on April 12, 2015, 10:22:43 AM

Some pics for those interested...

http://s1291.photobucket.com/user/cr749292/slideshow/Black%20Betty

Title: Re: 390 Build for '68 Mustang 'vert
Post by: ScotiaFE on April 12, 2015, 10:58:35 AM

The car looks great!
The fuel level in the fuel bowels?
Which carb is it exactly?
The strong fuel odour is the most concern as that is causing a very rich "dump" at tip in.
I would look first at the fuel level and to make sure you are not over powering the fuel bowel inlet seats.
Do you have a vacuum reading at idle?

 
 

Title: Re: 390 Build for '68 Mustang 'vert
Post by: mlcraven on April 12, 2015, 11:12:19 AM

That is a drop-dead gorgeous Mustang, a show-winner for sure. Further to Howie's question above, whatever the carb is (assuming a Holley?) is it new out-of the box, original/rebuilt, swap meet/rebuilt, what? 

Title: Re: 390 Build for '68 Mustang 'vert
Post by: 63.5xl on December 15, 2015, 10:28:28 PM

How did that cam work for you this summer?