Gear ratio calculator, rear gears, and transmission ratios

[mgb260]

Rob, It may, but generally equal carb or fuel injection show very little difference. What you will notice is better throttle response, easier cold starting with no warm up and better mileage. I would need the specs for injectors and cfm of throttle body, TBI or port injection and I'll run it to see.

[mgb260]

Rob, My program had the Edelbrock Pro-Flow system in its library. Max TQ is 500 RPM's lower and HP 1000 RPM lower than with carb. This is with your cam advanced 4 degrees.

[mgb260]

Fuel injection is very tuneable. I think if you change timing and A/F mixture you would increase HP and lower TQ a bit. I'm going to show that last chart again in a different scale and by itself so it is not cut off.

[mgb260]

Pic:

[mgb260]

Here Goes!

[rficalora]

Great info Jim!

I just talked to Comp Cams & they recommended their XE266HR -- pretty close to what Kelley had.  Thoughts on 266 vs 264?  Looks like I'm down to one of those or the E303 (which is about $100 cheaper).

[mgb260]

Rob, Or advance your cam 4 degrees for free. I can run the XE266HR to see I there is any difference. I can do back to back carb and Edelbrock Pro-Flow fuel injected.

[mgb260]

Rob, Here you go!

[mgb260]

The fuel injection moves the power curve down for more TQ and less HP vs carb for more HP less TQ. I think A/F and ignition tuning will fix the HP to TQ ratio. The XE266HR doesn't seem much different to the XE264HR or the B303. It's higher lift probably isn't utilized by your heads and it would be a good idea to check piston to valve clearance. Most street engines don't need more than .500 lift. It has .544 IN and .555 EX lift. XE264HR has .512 @ both. B303 has .480 @ both and E303 has .498 @ both.

[mgb260]

If you wonder why I advance these cams 4 degrees it is not only to move the TQ curve down but also to get the Dynamic compression around 7. Straight up is only around 6.5.

[mgb260]

Rob, Is your Edelbrock the 4 barrel type or front throttle body? Do you know the injector size? Stock 302/5.0 was 19lb. Most use 351 size 28lb.

[rficalora]

Jim, the ProFlo is port injection.  Throttle body is 4-barrel type with 1000 CFM # 1.5" hg.  Injectors are 29lb Pico type.

[mgb260]

Rob, a few more questions. Average runner length and port height. Then I can input custom and get a closer dyno chart. It sounds similar to what we did for Chris Gill on his stroker Buick. I think your B cam advanced is the best choice. Why buy another that is close to the same performance?

[rficalora]

Can't seem to find that info online and am away from the parts till sometime next week so won't be able to measure till then.  I vaguely recall reading somewhere that the Pro Flo intake is based on the Victor Jr. but not 100% sure if my memory is right.

[mgb260]

Rob, Thanks. I'll figure it out.

[mgb260]

Rob, I used the Victor Jr settings in my program. Looks like over 40HP over carb simulations. Still about a tie but Comp cam may idle better due to lower duration. You can see that the Victor Jr intake wakes up at 3000RPM.

[mgb260]

Rob, Your cam has 5 degrees advance built in. The Comp cam has 4 degrees advance built in. Even though they are put at zero the advance is already there.

[mgb260]

Dan Masters uses the E cam with his Edelbrock Pro Flo injection. A little less duration and more lift than the B cam.

[rficalora]

I knew Dan has an E cam and he is happy with it.  But, if I'm going to swap cams, the XE264 or 266 seem like better choices.  Either way, I'm going to try it with my existing cam.  I'm just not sure how well the EFI system will like it.

[mgb260]

Rob, I agree with the XE264 but the higher lift on the XE266 makes me worry about piston to valve clearance, for a small gain in power.

[kstevusa]

From my experience, the XE 264 HR is perfect for a EFI street car.  As Jim noted earlier, the carbed and EFI Dyno very close. Larry Shimp and I confirmed this several times.  Same engine combo, Carb vs EFI.  No P to V problems.  E & B Cams= OLD School Tech.  OK to move up to early 21 Century tech. :-)

[MGBV8]

B-B-B-B-but Kelly.......

<iframe width="560" height="315" src="https://www.youtube.com/embed/XeOn5FjsYAI" frameborder="0" allowfullscreen></iframe>

[rficalora]

Yeah, yeah Carl...  Kelley already sent that to me to harass me.  You guys have convinced me.  Need to swap transmissions and resell my current one before I can buy a cam.

[kstevusa]

Carl, that video "kills me", LMAO

[MGBV8]

I know. It's a riot!