Thread: advice on 489

Tweet

Originally Posted by cvfb97

hey, brand new here. i recently bought a markv 454 block thats been bored .030 over. id like to build a 489. i dont have a vehicle to put it in yet, but the plan is a 3rd gen camaro. it will be 90% street with the 10% at the track when i can sneak away... as far as power specs, id like to be in the mid 500 range if not higher on both hp and tq... Theoretical parts list are as follows: scat cast crank kit with forged flat top pistons and forged rods, AFR heads (305 cc intake runner, 115cc chamber), edelbrock performer rpm airgap intake, holley 4150 800cfm carb. Im unsure of what im looking for in a cam.. max valve lift on the heads is .850. i would like a nice lopey sound but performance is more important. Am I on the right track? Any suggestions for what i should be looking for spec wise on a cam? feedback is appreciated...

99% of your driving will be under 4500 rpm's, so build a motor that will perform well from idle to 4500 and bolt on a 150 shot of N2O for those times when you want that other 1% up to 6200/6400 rpm's.

Assuming your block is honed and ready to go at a 4.280" bore, I would use the stock rods with upgraded bolts and the stock cast crank. Purchase SRP forged pistons from your favorite source, part number 141635-8. These have domes of 14 cc's and 5/64/5/64/3/16 rings. I like thick rings for street motors, saving the thin ones for race motors. Allow additional clearance on the rod and main bearings and additional gap on the piston rings to accommodate the 150 shot of juice. This will make a very sweet 460 cubic inch motor and you'll never miss the other 29 cubic inches that you planned for originally.

Aluminum heads will not work well with steel shim gaskets because of the different growths between the iron block and the aluminum heads due to heat. It tends to fret the aluminum. So, plan on using composition head gaskets, Fel-Pro 1047.

Your block deck height will need to be cut to 9.780" for zero deck. Using the 1047 gasket at 0.039" compressed thickness will give you a squish/quench of 0.039" and will help to prevent detonation on pump gas.

Heads will be Airflow Research #3610, Oval port, 265 cc intake runners, 109 cc combustion chambers. These heads, together with the 14 cc pistons will give the motor a 10.05:1 static compression ratio, just right for an aluminum-headed street motor operating on pump gas.

Bolt your 800 to an RPM intake manifold, NOT THE AIR GAP, just a regular RPM. Regulate fuel pressure to 5 lbs maximum at the bowl inlet. Install a 14" x 4" air filter assembly so that the motor can breathe.

Bolt on a set of equal-length headers, full length, with minimum 16 gauge tubes and minimum 3/8" thick flanges, 1 3/4" primary tube diameter. Install an "H" pipe immediately after the collectors for a sweeter exhaust note. Use 2 1/2" / 2 3/4" / 3" I.D pipe to the rear bumper with mufflers of your choice.

Use this cam....
https://www.summitracing.com/parts/h...5-12/overview/

Use a 10", 3000 stall converter and swap the rear gears to 3.73 with an Auburn limited slip. Replace all bushings in the rear suspension.

Maximize rear wheel and tire width.
.