Thread: advice on 489

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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...

This is completely the other direction than you're going, but a turboed LS1 will get you over 600 horsepower with less cost and be way more drivable. I just watched a video of a stock LS1 producing 633 horsepower with a turbo added, and then still get 25 miles to the gallon.just an option. If you want to stay with the big block, others can help you out more than I can. I don't have the experience to tell you what parts you need.

Had considered turbo-ing a lq4, but from what I've read it can be a bit of a PITA to package it in a 3rd gen camaro. Would also be my first turbo set up, which would be another can of worms. The motor build was kinda gonna be part of the whole "built it myself" satisfaction part, if that makes any sense... Would like to build a turboed lq4 one day though

My experience with the edelbrock air gap is that it performs poorly at part throttle: bad for the street.

They perform well when fully warmed up, and wide open throttle.

My advice is strip only. If you want something street-able, avoid the air gap and get something in a dual plane.

They do have the air gap in dual plane, would that be decent or still not suited for the streets? What would be optimal for my intended use?

Ran an air gap for a couple of years on a 327. Coast to coast running and long hauls.
Sucker slobbers all over itself until engine is warm. Even in 100 degree temps.
Now just have a plain rpm performer and have to smile at the guy who bought the
air gap. He does not understand why it won't run good when he first starts his 383.
Warned him but he just did not hear that when he was looking through his rose colored
shades.

I'll stick with ya no matter what you use. I have a gen 3 Camaro also and I kinda like em. Others on here jabbed me about it but I think we're still friends

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.
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thank you for spelling it out for me techinspector. All i have is block thats .030 over stock stroke crank. was looking at a scat 489 rotating assembly for everything for the bottom end. if i do get the stock sized rods and my crank is decent enough to run, how much power would you guestimate it to put out?

Originally Posted by cvfb97

thank you for spelling it out for me techinspector. All i have is block thats .030 over stock stroke crank. was looking at a scat 489 rotating assembly for everything for the bottom end. if i do get the stock sized rods and my crank is decent enough to run, how much power would you guestimate it to put out?

Judging by dyno tests run with very close to this combo, same engine size, Performer RPM, same heads and nearly the same cam, Holley 950 Ultra HP 4150-series carburetor, 600 hp @6100, 580 ft/lbs @4200. Deduct 5% for the smaller carburetor and end up with 570 horsepower and 550 ft/lbs. A 150 shot of juice would put it at 720 and 700. Figure $650 for the juice. Stalling the converter at 3000 rpm's shows 508 ft/lbs without the juice, 658 @3000 with it. i think it would take a blower to drive around you.

Most everybody is fooled by the small oval port AFR heads. With 265 cc intake runners, you might think that they would be just right for haulin' grandma to bingo and back, but AFR has hit a home run with these little jewels. I don't know, I might trade off the 800 for a 950...... 600/580 is mighty attractive to me, naturally aspirated.

You also have to consider that they tuned the living hell out of the motor on the dyno, so you may have a considerable amount of tweakin' to do after you get it running. Change one thing at a time and then test.
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considering there arent a whole lot of fast street cars in my neck of the woods, even 550 would great. Seeing as how i havent purchased anything as of yet, a 950 isnt out of the question. thank you for the advice

also, the afr 3610- those will match up with the mark5 block alright?

Originally Posted by cvfb97

also, the afr 3610- those will match up with the mark5 block alright?

Call AFR and talk with their tech guys.....877-892-8844
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I was also wondering how you felt about centrifugal super chargers? Would the stock crank hold up to 6-8 lbs of boost? I looked up the 3610 heads you suggested, the first ones I found were 112cc if I remember correctly. Using a cr calculator I found online, if I used the 112cc heads my ratio would be around 9.8. would that ratio work for pump gas with no intercooler?

Originally Posted by cvfb97

I was also wondering how you felt about centrifugal super chargers? Would the stock crank hold up to 6-8 lbs of boost? I looked up the 3610 heads you suggested, the first ones I found were 112cc if I remember correctly. Using a cr calculator I found online, if I used the 112cc heads my ratio would be around 9.8. would that ratio work for pump gas with no intercooler?

Centrifugal superchargers are probably the easiest to package in a tight engine compartment and it shouldn't be too difficult to mount an intercooler in a 3rd Gen Camaro if you wanted to. You would want hood space to bolt a bonnet (or bonnets) to the top of the carb(s) and space somewhere else to mount a filter system. You'll also need blow-through carb(s).

The size of carb(s) or CFM required for a given application can be calculated by the following formula A: {(CID x RPM) ÷ 3456} x {Boost ÷ 14.7) + 1} = CFM required.
Let's plug in some values and see how this works....
798.61 X 1.544 = 1233 CFM
This would probably require a 2-4 intake manifold with two 650's and a split supply pipe with two carb bonnets. I've never seen it done, but that would make the most sense to me.

It is my opinion that 8 lbs of boost would be no problem with a stock 454 crank up to 6200. It's revs and detonation that kills cranks. By the way, find a quiet time to really pay attention to this, read and heed......
http://www.contactmagazine.com/Issue...ineBasics.html

Chamber volume depends on extent of CNC machining.....
#3610 CNC bowl blend, Partially CNC Chamber w/ Hydraulic Roller Springs 109cc
#3610-1 CNC bowl blend, Fully CNC Chambers w/ Hydraulic Roller Springs 112cc

A blower on pump gas will want somewhere between 7.5:1 and 8.5:1 static compression ratio, depending on amount of boost and mixture temperature. Some guys will tell you to use 9.0:1 or 9.5:1 with a blower, but the higher the SCR is, the less blower boost you can blow into the motor if using pump gas. If you are using straight methanol or ethanol, heck yeah, run it up to 11:1 if you want to. You will be able to buy pistons to accommodate ~8.00:1 for use with pump gas. Not sure of your elevation, but if you live in Greenfield, Indiana, your elevation is about 882 ft above sea level and you would want to limit the boost to about 8 psi so that you could run the motor on pump gas without detonating it.

Take a look at this Final Compression Ratio Chart from Blower Drive Service......
Technical Charts
Across the top is boost in psi, down the left side is static compression ratio. The shaded areas are OK for pump gas. The unshaded areas will require a better fuel such as E85 or straight ethanol or methanol or race gas.

Here is the formula for figuring Final Compression Ratio
Final Compression Ratio (FCR) = [ (Boost÷14.7) + 1 ] x CR
8 divided by 14.7 = 0.544
+1 = 1.544
1.544 X 8 = 12.35:1, rounded off on the chart to 12.4:1

I'll look around and see if we can juggle pistons with 109 and 112 to figure it out to around 8.0:1 SCR.
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