Thread: 350 ramjet or zz4 turnkey?

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I have a 70 chevelle, was a 3 speed/straight 6 is now a 350/350 thats old and tired. thinking of droppin on of these GMPP engines plus a 700R4. both have around 400 foot pounds and 350 horse. Any input would be great.

I put a new ZZ4 in my nova last year, my wallet is still crying, but its a great motor. Very responsive, good torque...it pulls hard, really rips at higher rpm's too. Considering the cost to assemble your own engine with quality parts, the ZZ4 is actually not a bad deal. I considered the ramjet too, but cost was prohibitive. Besides, Im more of a carb guy...I always gotta have something to tinker with.

....Pablo, At www.sdpc2000 a 350 HP/400 TQ 350 Ram-jet is almost $5000 & a 450 HP/550 TQ 502 Big Block is $5800 {no carb or ignition though} {part #12568778}. A 150 more Ft. Lb's of TQ for a grand more??? Why not put in a big block. Lots of room for one in a 70 Chevelle ,,,,,, Plus it's got a steel crank for when 550 TQ isn't enough & you want to add a blower! ;0 Bill

The ZZ4 is a heck of a motor. I have a ZZ430 clone (different heads, bigger cam) and it's scary fast.

I'd like to tinker too, but with her body(no pun intended). I'm new to this game so I not sure if a 350 ramjet + 700r4 w/ 2000 stall + stock rear maybe 3:06(was oig a 250 striaght 6 with standard 3 speed) + 28 - 30 inch tires on 18 - 20 inch rims will work?

I think you'll be a bit sluggish with that setup due to the tall tire and 3:06 rear ratio, and your converter stall is rather low too. The steep first gear of the 700r4 and torquey ramjet will help compensate a bit, but not enough in my opinion. If you want something that is streetable and will give you better leap off the line while still keeping comfortable cruising rpms, I would go with a taller rear gear, like a 3.70 or 4:11, and a stall around 2400-2600. These are ballpark numbers, you may want to take a look at this neat rpm/gear ratio calulator: http://www.angelfire.com/fl/procrastination/rear.html
Good luck!

Originally Posted by pablocusa

I have a 70 chevelle, was a 3 speed/straight 6 is now a 350/350 thats old and tired. thinking of droppin on of these GMPP engines plus a 700R4. both have around 400 foot pounds and 350 horse. Any input would be great.

With a sled that big and heavy, I'd go big block. Takes a long arm and a lot of torque to get all that dead weight and mass moving. The longer the wheelbase, the more flexing and bending things do before the car actually will start moving forward.... Big heavy cars need torque, not horsepower, to work good.

To assist getting the thing moving, why not a 5 or 6 speed manual instead of the automatic/overdrive?? You can gear them lower and stretch out the overdrive further then an automatic can. Also, a manual trannie consumes less horsepower and creates less heat then an automatic??? Shift them gears! Makes the drive a lot more fun!!!!!!

Have you considered a 350 H.O. motor? This engine has better heads and is cheaper then both of the crates you are considering. With headers, I saw a 350 hp rating on this engine. Also, with a better cam, this engine has alot more potential.

Why not build yourself a custom engine?
This way you pick the parts and build excatly what you want.
My fav. would be a 496 BBC with a hyd. roller cam,well ported 781's with 2.19/1.88 valves,RPM Performer,flowed 750 vac. carb.