In search of the BEST add on parts combination for a 351c 4v rebuild . . .

I would personally try to go with a flat top piston and a closed chamber head.The Blue Thunder intake is a dual plane design as far as I know.I ran one for a while and it was amazing!I would recommend a cam in the .550" to .575" lift range and a duration in the 240-250 deg @.050 range on a 110 centerline.This is very simillar to the Cleveland I had in my Pantera and it made 340HP at the wheels.If you want the absolute best advice give Mark McKeown a call @301-246-9225.He is very helpful and an absolute genious when it comes to Clevelands.

Blayre,

Here is the combo in my '74 Pantera:

Stock 351C 4 bolt block, .020 over, no oil restrictor kit
Stock crank, micropolished
Stock rods, shotpeened with ARP wavelock rod bolts
Keith Black hyperuetectic pistons, .100 dome delivers about 10.3:1 compression
Plasma moly rings, Clevite 77 bearings
Stock Melling oil pump (not high pressure or volume)
Pete Jackson silent gear drive
Fluiddampr balancer
Stock steel flywheel, dual friction clutch
Balanced reciprocating assembly
Stock baffled oil pan and pick-up, 6 quarts of oil (not synthetic)

Cam specs:
Comp Cams roller: 236 int. & 244 exh duration @ .050, .619 lift, 112 degree lobe separation, ground straight up (not advanced or retarded), installed straight up.

Heads:
Stock Cleveland 4bbl open chamber
Bowl blended and gasket matched
Machined for screw in rocker studs, guide plates
One piece stainless steel single groove 2.19 int & 1.71 exh valves, 3 angle valve job
Triple springs (matched to cam), hardened locks and retainers
Crane 1.7 roller rockers to reduce valve lift a bit (stock is 1.73)
I have about $1200 into the heads, parts and labor.

Misc:
Edelbrock Torker, gasket matched
Holley 750 vacuum secondary
MPG intake and exhaust restrictor plates
Mallory dual point dist with Pertronix Ignitor
MSD 6A, Blaster 2 coil
Taylor Spiro Pro wires
Split Fire spark plugs, .55 gap
Stock fuel pump
FelPro blue Permatorque head gaskets
34 degrees total timing by 2800 RPM

The power band on this motor is about 1500 to 6500 RPM. It wants to go further, but the rods and hydraulic lifters will become an issue above that. I built the motor with that in mind. It idles at about 750 RPM with no drama. This motor makes about 400 HP at a cost of about $4000 from air cleaner to oil pan for all parts, machine work and labor, heads included. The weak link is my exhaust: the headers are 1 5/8, dumpimg into 1 3/4 collectors! The pipes are 2 inches! If I weren't selling this car (I also have an '86 5-S), the plan was to go to a 2 inch primary header and a 2 1/2 inch pipe. This would probably yield about 450 HP as the current exhaust is a major restriction. I'm told with some serious tweaking, and possibly stepping up the cam a bit, I can get to around 500 HP.

I credit the roller cam and valetrain, along with the port plates for the wide and powerful powerband (although the port plates burned the paint off the upper exhaust port, where the lower head bolts are). This motor is BRUTAL compared with the stock 351C in my '86 5-S, which is supposed to have about 350 HP. This car is a lot of fun to drive with this motor in it. I expect it to live for a long time as well. It gets about 15 (or so) MPG, even with my foot in it. I gave you a full rundown on my motor so you that you have an idea of a real world combination.

Good luck!

Michael

Blayre,

I understand you want a motor for street & track racing, with a relatively modest goal of 375 bhp. 15 mpg fuel economy. Powerband of 2000 to 6500. Want to use your 4V open chamber heads.

My first suggestion shall be a 3 3/4" stroker kit, taking you to 383 cu.in. This will help throttle response with the big-port heads.

Second, toss the stock rockers for a set of roller rockers & adjustable valve train. You'll pick up 15 bhp in the process.

If you want to keep the induction system under the engine screen go with the Blue Thunder intake & approx. 750 cfm Holley. If you want to poke the induction through the engine screen, try the Parker racing funnel web & port stuffers.

Call a cam grinder that knows clevelands, like MME or Reeds, to have a cam ground to your needs. They can take into account the compression ratio limitation of your open chamber heads.

You need an oil pan designed for track racing.

Look back at previous threads at this bulletin board, the DeTomaso mailing list & the Cleveland engine forum.

good luck, keep us informed as your build up progresses.

George
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