big block chevy bench racing

[1988montecarloss 2]

some big block parts showed up on craigslist today, more specifically, a set of world merlin 345cc heads, just got back from the machine shop with brand new harland sharp rockers and stud girdles for $1500 OBO, the guy also has a 4.25" stroke steel crank and forged h-beam 6.385" rods, just bench racing here but do you think with a big enough cam and 12:1 comp it could make close to 700hp on 91 octane and put my heavy 71 monte into the mid-low 10's without spray?

i dont know much about big blocks and have never really looked into one so thats why i ask, ill probably still go turbo 5.3 in my 71, but i do still have an 88 monte in my driveway thats been waiting for another motor for two years now.....

[Scott Liggett]

Not sure how much your Monte weighs. But, my old boss's wife's 69 Camaro had a 468, 10.6:1 comp, Brodix 345 cc heads, .660 lift and 250 dur @.050 solid roller, Brodix single plane, and 1050 Dominator, 3.73 gears. Ran 10.60's at 125 mph after driven to the track. The car was all steel.

[1988montecarloss 2]

Not sure how much your Monte weighs. But, my old boss's wife's 69 Camaro had a 468, 10.6:1 comp, Brodix 345 cc heads, .660 lift and 250 dur @.050 solid roller, Brodix single plane, and 1050 Dominator, 3.73 gears. Ran 10.60's at 125 mph after driven to the track. The car was all steel.

im not real sure what it weighs either, but i figure it has to weigh at least 3800 or so, i have all i can do to push it on flat ground haha, do you know what the camaro was running for a trans?

[Orange65]

700 HP with a 496 and 10.25:1 is easy- most magazines have done it and have the articles on line. Will it get your Monte in the 10's? Most likely, but it will depend on the weight and other driveline factors.

A friend of mine has a 496 with 10.25:1 compression, .67"ish lift roller, and an 850 CFM carb that dyno'd at 690 HP.

The only potential problem I see with what you listed is the heads. If those heads have 345 CC intake runners, I think that the heads may be too large for a 496 short of all out race. You may need to build a 565 or something along those lines to get good port velocity. Also, they are cast iron. (Also note that they are less than $500 each bare from Merlin, so the cost listed is not that good of a deal).

[Beagle]

^^ pretty damn big port ... The springs need to match the cam. It may not be a bargain if you have to set them up again when they don't match what you choose for a cam. I wouldn't personally let the spring package already on the "bargain" head dictate the rest of the build.

Pushing Chevy's... queue SBG, who knows more about pushing GM's than anyone else here! Come to think of it, he knows a lot about pushing Fords too. Hmmm.

[Scott Liggett]

im not real sure what it weighs either, but i figure it has to weigh at least 3800 or so, i have all i can do to push it on flat ground haha, do you know what the camaro was running for a trans?

TH400 with 3000 stall. There was nothing exotic about the car at all. Ran on Arco 91 octane most days. She drove the shit out of it. Then her husband redid the motor with an 8-71 blower, two holley 750s and she was making close to 950 hp on pump gas.

[Barry Donovan]

there is a lesson with trannies to be had ...

as gm makes 'em bigger they slip more away.

I had a real weight 3700# four door chevelle..as a cheapskate kept the I-6 auto and bolted to a simply tight 350.

I was as pissed off as thrilled (the car popped wheelies- I would not even guess >400hp)

you want tens, get a racing dig in the gears. I learned it by being a poorboy.

the old 3 speed TH series stuff can go to hell.


they even have a 6.2 diesel with 500 foot pounds screaming to 4.56 gears..wondering why it is slow and lacking power (m1009 military).

[TC]

Just remember it only takes 500hp in a 3000lb car to run mid 10's........The key factor is Traction........... because all the power in the world mean nothing if you can't get it to the ground.......

[1988montecarloss 2]

Just remember it only takes 500hp in a 3000lb car to run mid 10's........The key factor is Traction........... because all the power in the world mean nothing if you can't get it to the ground.......

the car will pull the tires with a small block, traction wont be an issue

[SpiderGearsMan]

the car will pull the tires with a small block, traction wont be an issue

what car again ?

[1988montecarloss 2]

what car again ?

the 71 monte

[anotheridiot]

If you are running unleaded pump gas, make sure you have hardened seats installed in those heads or you will need to add a lead substitute in your gas I think.

[JeffMcKC]

Thats way to big of head for that engine. Your getting way of path to get down track with it. a big cams going to make it worse. I would not be buying any of it.

[Mater]

i believe most moddern aftermarket heads all have hardend seats.

[1988montecarloss 2]

i believe most moddern aftermarket heads all have hardend seats.

x2, im still going turbo LS though, big blocks are too expensive