Ok this helps, Do your 305 heads have new springs or original springs?
I do not believe your heads are killing the time. You just have too big a cam with not enough stall for THE DRAG RACE TRACK (this is to optimize your 60 foot. ) With that combo and heads and supposed compression you should be well into the 1.60 sixty foot times
The duration is just too much for your Intake and stall to overcome at low end. The cam you picked pulls to 6500-7000 and you shift at 5800...??? SO yes the potential for more power and torque are there but your combo is off. SINCE you are drag racing TORQUE IS KING
You need as much torque at at least 1000 into stall speed.
SO if you have a 3800 stall you want at least 2/3 of your full torque out put in the 2800 range on the cam. (THIS IS FOR DRAG RACE optimal launch)
Your cam probably has good torque starting at 3000-4000 range- you need a 4000-5000 stall for the launch and 60 foot you need.
JUST not much you can do with the wrong combo you have to deal with it - make the best of it as you are selling it anyway right.
AGAIN the heads should not be the issue- try looking into your ignition What is the initial timing (balancer) and what is your totally timing? (when all your timing comes in on the mechanical distributor)
What ignition are you using this will be another area to help on your cars power and all around performance with ANY HEAD combo?
We ran a 274 comp cam with roughly the same set-up better heads little bit more compression (12-1) 11.40 all day on a 3000# car.
4.10 gears 4000 stall 1.40 60 foot.
12.90 combo street car 3000# weight - 280 comp cam Magnum hydraulic cam, 327 true flat top 9 to 9.5 to 1, 041 heads (like fuelie heads 1.94 1.5 valves (NO PORTING AT ALL stock just reconditioned, seats springs guides etc...normal stuff) RPM Edelbrock intake, unilite distrib (12-14* initial / 38* total advance) 2500 stall, 3.73 rear gears 24" slick (real gear ratio 4.10 most likely because of the undersized slick...we were trying to keep a 7.5 rear together here...lol
) 700 cfm dble pump holley carb This is a great street strip combo VERY FUN ON THE STREET... ET is respectable but will not impress the real drag race guys.
WHEN you build any car you really have to make a choice as to its MAJOR use...if it is every weekend to the track and that is most important to you, BUILD THE CAR TO RUN THE TRACK and suffer with the street low end- sluggish shifts on standard around town driving.
IF you want a exciting street car, you want the cam that gives you the most lift with little amount of duration (215-235 @ .050. 1.6 rockers help on a 260-280 lift cam get even more lift on the intake valve - NOT affecting the duration. Tinkering with initial timing will also create low end torque quicker, LIGHTER distributor advance weight springs will to again help the cause. You need a distributor that can be adjusted as you do not want your full advance over 40* timing at full throttle - unless your engine is modified to take it. (usually never needed over 40* anyway)
REMEMBER - with all this tinkering other things will suffer gas mileage being one of them - some time heat (advance etc. so do what your car can handle) Be reasonable as there is a LIMIT for every motor.
For all you know your could be at your limits and have done everything you can with your combo to eek the last bit out... (I doubt it on this one )
IF you get caught up in the TRACK ET's you will kill yourself on the street driving... (naturally aspiration motor) ET's get quicker and street ability will go down.
There is a tolerance level for each person. we are all different and will all have a different level of what we think is acceptable for a street car. My guide line is if you can not freeway drive for a 1/2 hour WITH FREEWAY NORMAL SPEEDS it is NO LONGER A STREET vehicle driver.
This is where OVERDRIVE trannies have become the norm and give cars advantage to race and drive to the track.
I am rambling on now...lol
If the heads are that inexpensive and you have the time Go for it and see what happens WORSE case you will have that knowledge first hand. That is how GOOD REAL knowledge is learned. Just try not to learn the same thing over and over...lol.
J D RACE AND RESTORATION
MUSCLE CAR DIFFERENTIAL SPECIALIST
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