HP estimate... mild BB build
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,080
Likes: 565
From: Allen TX
HP estimate... mild BB build
If anyone has a copy of Desktop Dyno (I know it may be a bit antiquated) or want to take a guess, I would be interested in your thoughts on the following combo (no need to nitpick it... I didn't build it. It's in a car I am looking at):
454 bored .060 (467+ cubes)... 9.7:1 CR
aluminum Pro Comp heads (not a great reputation, I get it)... https://www.competitionracingsupply....te_3021_c.html
Herbert Cams roller cam https://www.herbertcams.com/240-250-...0lc-2000-6200/
LS6 "low-rise" intake
Holley 750 DP
Hooker 2" primary headers... 3" out to 2.75" Flowmaster mufflers
Owner has never had it dyno'd.
TIA!
454 bored .060 (467+ cubes)... 9.7:1 CR
aluminum Pro Comp heads (not a great reputation, I get it)... https://www.competitionracingsupply....te_3021_c.html
Herbert Cams roller cam https://www.herbertcams.com/240-250-...0lc-2000-6200/
LS6 "low-rise" intake
Holley 750 DP
Hooker 2" primary headers... 3" out to 2.75" Flowmaster mufflers
Owner has never had it dyno'd.
TIA!
Last edited by WA 2 FST; Oct 7, 2019 at 09:43 AM.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Drop VortecPro (Mark) a line......he is a member here and enginehead extraordinaire........he did a combo like the one you are suggesting and if I remember it made like 550 hp.......how he did it through that god awful intake is beyond me.......
Jebby
Jebby
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,043
Likes: 4,396
From: Marlton NJ
That's a pretty strong street cam, and those heads actually flow pretty well. I vote for nearer to 550HP. Even with the LS6 intake. Have seen several dyno'd in that range with similar size cam.
Curious. What kind of idle rpm and vacuum do you get? 8-900?
12?
Curious. What kind of idle rpm and vacuum do you get? 8-900?
12?
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,080
Likes: 565
From: Allen TX
Melting Slicks
Joined: Oct 2008
Posts: 2,154
Likes: 69
From: Regina Sk Canada
That is a big cylinder head, 320 cc intake runner, that may be too much head for what you are doing. I had a set of AFR 305 rec ports on my 468 and i made 708 HP with them. Mind you i built a 12-1 motor with a big solid roller, looking back i should have had a 320 cc head.
My 427 BBC +.060= 440 had 11.25-1 compression, EDDY rpm performer oval port heads, 280 cc runner. .585/.585 with .245/.255@.050 0n a 112LSa Hyd roller. made 550 hp and 513 tq. Strip dominator intake and an 850 dbl. Had a nice idle to it drove well on the street very responsive.
Honestly it it was my Motor, i would go with a set of cast iron 990 rec ports, your cam is fine, intake i imagine is for fitment issues? Look for a 780 holley with dual metering blocks and vacuum secondaries and a 1-7/8 primary tube header. That would be a nice street motor.
My 427 BBC +.060= 440 had 11.25-1 compression, EDDY rpm performer oval port heads, 280 cc runner. .585/.585 with .245/.255@.050 0n a 112LSa Hyd roller. made 550 hp and 513 tq. Strip dominator intake and an 850 dbl. Had a nice idle to it drove well on the street very responsive.
Honestly it it was my Motor, i would go with a set of cast iron 990 rec ports, your cam is fine, intake i imagine is for fitment issues? Look for a 780 holley with dual metering blocks and vacuum secondaries and a 1-7/8 primary tube header. That would be a nice street motor.
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Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,080
Likes: 565
From: Allen TX
That is a big cylinder head, 320 cc intake runner, that may be too much head for what you are doing. I had a set of AFR 305 rec ports on my 468 and i made 708 HP with them. Mind you i built a 12-1 motor with a big solid roller, looking back i should have had a 320 cc head.
My 427 BBC +.060= 440 had 11.25-1 compression, EDDY rpm performer oval port heads, 280 cc runner. .585/.585 with .245/.255@.050 0n a 112LSa Hyd roller. made 550 hp and 513 tq. Strip dominator intake and an 850 dbl. Had a nice idle to it drove well on the street very responsive.
Honestly it it was my Motor, i would go with a set of cast iron 990 rec ports, your cam is fine, intake i imagine is for fitment issues? Look for a 780 holley with dual metering blocks and vacuum secondaries and a 1-7/8 primary tube header. That would be a nice street motor.
My 427 BBC +.060= 440 had 11.25-1 compression, EDDY rpm performer oval port heads, 280 cc runner. .585/.585 with .245/.255@.050 0n a 112LSa Hyd roller. made 550 hp and 513 tq. Strip dominator intake and an 850 dbl. Had a nice idle to it drove well on the street very responsive.
Honestly it it was my Motor, i would go with a set of cast iron 990 rec ports, your cam is fine, intake i imagine is for fitment issues? Look for a 780 holley with dual metering blocks and vacuum secondaries and a 1-7/8 primary tube header. That would be a nice street motor.
454ci, GM crate motor
~9.5:1 CR
AFR 305 heads (CNC chambers, as-cast ports)
Edelbrock RPM AirGap intake
Comp Cams hydraulic roller cam (230/230, .578/.578, 110 LSA)
Holley 950 HP carb
Hooker 2 1/8" sidemount headers, JCL baffles
Richmond 5-speed trans
434rwhp @ 5600rpm
450rwtq @ 4400rpm
______________________________________
these numbers at the rear wheels would probably be ~520hp at the flywheel. I would _think_ that the above combo I mentioned in the OP would be pretty close. Larger cam, little higher compression, but inferior intake and smaller carb. Head flow at lower lift/duration may be a wash, although I'm a big fan of AFRs and how they create airflow velocity very efficiently. I haven't driven the car yet... I am considering purchasing the car that has the combo mentioned in the OP. If I do, then I most likely will get an L88 hood, and then have some quality options to run a better intake and swap the heads for something you mentioned, or another set of AFR305's. That being said, if the OP combo is already at/near the level of the engine I built in '04... I'm not sure it is worth all that expense.
I would not be looking to build anything close to what you have. That's for another car in my garage.
Race Director
Joined: Mar 2016
Posts: 14,343
Likes: 8,154
From: Napa Valley California
Sounds like a nice setup.
If I were you, I would start a new thread and ask which intakes would work well with your build and still fit under your hood.
I've read on several threads where members were running Edelbrocks, Weiands, and others under the stock earlier hoods.
You might need a drop base air filter, but a different intake might give you some additional hp.
If I were you, I would start a new thread and ask which intakes would work well with your build and still fit under your hood.
I've read on several threads where members were running Edelbrocks, Weiands, and others under the stock earlier hoods.
You might need a drop base air filter, but a different intake might give you some additional hp.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
Those heads have bad reps for the cheapass valves and springs they throw in them. They flow good and make good power. A guy near me bought a 496 with the same heads. Dropped an intake valve head at IDLE! Busted block and ate one head. He was asking 3k. He got 500. If heads were bought complete and assembled, pull them and replace the valves with Ferrea or some other quality valve. That motor should do 525-550 pretty easy.
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,043
Likes: 4,396
From: Marlton NJ
Those heads have bad reps for the cheapass valves and springs they throw in them. They flow good and make good power. A guy near me bought a 496 with the same heads. Dropped an intake valve head at IDLE! Busted block and ate one head. He was asking 3k. He got 500. If heads were bought complete and assembled, pull them and replace the valves with Ferrea or some other quality valve. That motor should do 525-550 pretty easy.
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,080
Likes: 565
From: Allen TX
Those heads have bad reps for the cheapass valves and springs they throw in them. They flow good and make good power. A guy near me bought a 496 with the same heads. Dropped an intake valve head at IDLE! Busted block and ate one head. He was asking 3k. He got 500. If heads were bought complete and assembled, pull them and replace the valves with Ferrea or some other quality valve. That motor should do 525-550 pretty easy.