jamesjones

iTrader: (1)

I'm currently building a 72 Blazer into a mild prerunner. I need an engine
for it that can put out around 400-425 horsepower and roughly the same
amount of torque. The Blazer is going to be used for street driving and
high speed desert and dune running so I'll probably need most of the power
between 2500-4000 rpms. The kicker is, since the truck will be spending
quite a bit of time in Mexico, I need it to run on 87 octane just in case I
run out of gas down there. Is this something that can be pulled off? Let me hear some ideas guys. Any info you provide would be greatly appreciated.

Thanks
James

This is what it will be going in.

mzoomora

iTrader: (36)

You could always do a timing controler for when you are using low octane fuel, similar to a nitrous retard. I would think you could do it. With the right amount of cam overlap, about 10-1 max compression, run the engine cool, and keep the timing under control. The torque is easy, but the HP will be the challenge, especially in the power range you are thinking of. You would probably need to peak around 5500-6000 for that HP target. The GMPP ZZ383 turns 425hp @ 5400 and 460tq @ 4500. Kinda high in the rpm range for peaks, but I am sure the power band is pretty flat before that. It is 9.7-1 compression and designed for 92 octane, so with some timing pulled you could probably run 87.

98RedZone

iTrader: (1)

The engine mzoomora mentioned would probably work good, but I think you could lower the compression by using the ZZ4 shortblock (or similar), and using an Aluminum head like AFR's 180cc or 195cc. You can get them in a 68cc chamber instead of the 62 (I think) Fast Burn GM head.

jamesjones

iTrader: (1)

What compression ratio should I shoot for with aluminum heads to still be reliable on 87 octane?

mzoomora

iTrader: (36)

I would keep it inder 10-1. With the right timing and keeping it cool, you would be fine.

jamesjones

iTrader: (1)

Wow, that high, really. If I were to go the zz4 shortblock route and go with say 74cc AFR heads(zz4 is 10 to 1 with 58cc heads), what kind of compression would that long block have? What cam should I go with in that long block to get the powerband as close to where I need it as possible?

jamnut

iTrader: (4)

I copied this off of another board that I made this post on, but I have this badass drive train for sale that comes with it's own carrying case, a 1980 Elcamino body.

MOTOR
383 cu/in
4 bolt mains
Eagle Stroker Crank
GM "Pink rod's"
Speed Pro Keith Black 9.8-1 Hyperpathetics
Canfield 205's with 2.05" valves
1.6 roller rockers
Child's & albert rings
Durabond Bearings
ARP Wavelock rod bolt's
Cloyes True roller timing chain
Custom Ground Comp Cam's Muscle car grind 520/528 230 on a 110 LSA cam ( Flat tappet )
Polished AFR dual Plane high rise intake, port matched to heads
Speed Demon 750 Carb
Comp Cams XE Push rods
DynaTech Coated headers
Unilite distributor
MSD 6AL
MSD Blaster Coil
Accel Plug wires
Chrome Alternator
Billet Alternator mount
chrome waterpump
Billet pulley's
Race balancer
SFI flexplate
440 BHP @ 5750 rpm's, 465 FT/LB's Torque @ 5200 rpm.



Fuel system
12 gallon fuel cell ( foam filled )
All braided stainless lines -8 to filter & -6 after pump.
All AN fittings.
Big *** Fram External fuel filter like you see on race cars, hanging out of the back of the car.

Transmission

TCI Superstreet fighter 3600 stall
TCI Race transmission, manual valve body, conventional shift pattern
Pro Ratchet shifter

Rearend
9" Custom Housing
31 Spline Axles
Ford Posi, ( rebuilt very good rebuild )
Rear Disc Brakes.
Rearend assembled by Crazy Ed in D'iberville.

Suspension
Edelbrock adjustable upper control arms
Edelbrock boxed lower control arm's
Edelbrock support bar's.

Interior

Moroso Switch panel
full gauges
Toyota Supra seats
4 point harnesses
NO CAGE

Battery relocated in bed.

3rd gen Camaro wheels with 275-60-15 Nitto 555r's in the back.

The Diablo body has some hidden rust, but is still in very good shape, but all of this could be transferred into any Gbody. Monte Carlo, Cutlass, Elcamino, Malibu.

Needing $8k.

98RedZone

iTrader: (1)

I would shoot for low-mid nines, AFR would be able to tell you with 68 and 74 heads.

BOWTIE

I would follow more along the route with mzoomora, with the stroker. It will make more torque with everything being the same and bring the peak power down some RPM compared to a 350 with everything being the same. I would, however, stay with the 4" or so bore (rather than building a 400 + cu inch motor) due to the cooling aspects. With that said, a combination I have been planning, but not seen any real results on (other than a test performed by Super Chevy on an 11.0/1 427 ci, they made 572 ft lbs tq at 4200 and 515 hp at 5400) is a 383 with a slight dish (-12cc) piston with the Edelbrock ETEC 170 heads. This should give you about 9.6-9.7 to 1 compression. These heads use a vortech type intake so in your case I would follow it with a Performer RPM air gap vortec intake and either the Edelbrock Prformer RPM hydraulic roller used in the Super Chevy test or a slightly smaller Hydraulic Roller like one of the Comp Xtreme Energy cams (like this one 224/230 at .050 .502/.510 lift 1900 rpms-5600 rpms). I am planning on building one of these for a 1991 4wd Suburban, but plan on using an even smaller camshaft 218/224 @ .050 Extreme Roller, but alos retaining the fuel injection. Keep in mind these heads with an Edelbrock cam and Edelbrock fuel injection made 440 hp and 425 ft lbs tq (435 hp and 435 ft lbs with air gap RPM manifold and Edelbrock carb) on a ZZ350 short block. Add another 30-35 cu inches and you will add as much tq and bring the peak tq and peak HP points down considerably in the power band with no other changes (HP numbers may not change since they are affected by RPM and with out a camshaft change the peak numbers will drop in the RPM range).