383 hp increase
Thread Starter
Cruising
Joined: Aug 2014
Posts: 14
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383 hp increase
Looking to get more out of my 383, looking for advice. Right now have 383 with flat tappet 230@230 at .50, with average aluminum heads flowing around 200 at .500, wieand single plane team g, and holley 750 double pumper making around 425-450hp at flywheel,
Changing 383 to comp cam xs282s 244int 252 exhaust at .50, comp ultra gold rockers, comp lifters and afr 195 heads. With this new combo thinking around 550hp at flywheel, 450rwhp, it has 3 speed rebuilt turbo 350 with transmission cooler, and 3500 stall with 3.55 gears, your thoughts
Changing 383 to comp cam xs282s 244int 252 exhaust at .50, comp ultra gold rockers, comp lifters and afr 195 heads. With this new combo thinking around 550hp at flywheel, 450rwhp, it has 3 speed rebuilt turbo 350 with transmission cooler, and 3500 stall with 3.55 gears, your thoughts
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I had almost the exact same setup with a solid flat tappet cam with 248@.050 and .540 lift intake and exhaust. I was running a Victor Jr intake and a holley 750 DP and later went ot a Barry Grant 825. The max I ever got and we did a lot of dyno runs and tweaking was 409 RWHP. I was pretty stoked to get that out of it. 450 RWHP is not going to happen with that setup. Stick a roller cam in it and you might get closer. I did that and went to 210 AFR heads and fuel injection. Never dynoed it before selling it but it was faster than the other setup.
Safety Car
Joined: Oct 2004
Posts: 3,926
Likes: 739
From: Youngstown Ohio
Hard to say if that combo's good for 550hp, but check out AFR's proven combos.......should give you some possibilities...
http://www.airflowresearch.com/dyno.php
http://www.airflowresearch.com/dyno.php
Le Mans Master
Joined: Oct 2007
Posts: 7,453
Likes: 976
From: RI, Now Franklin/Nashville TN
The link to AFR's website with 195 cylinder heads on a 383 shows that 500 Gross HP is easily obtainable with a roller cam. I can tell you that my L-82 355 with the AFR 180's and Howards roller cam (.525/.525, duration 219/225) certainly has some legs but no dyno sheet yet. AFR 180 heads on a 355 with a very mild hydraulic Comp Cams Magnum cam (.470 lift) and 9.5 compression shows 430 Gross HP…..I am very interested to see what my 355 AFR 180 head L-82 does with a lot more lift roller cam and 10.2:1 compression….
I would think that you are going to need about 550-575 Gross HP to make 410 RWHP in C3 with a Turbo 350 Automatic….doable with a 383 with AFR 195's, 10:1 + compression and a pretty stout roller cam.
I would think that you are going to need about 550-575 Gross HP to make 410 RWHP in C3 with a Turbo 350 Automatic….doable with a 383 with AFR 195's, 10:1 + compression and a pretty stout roller cam.
Last edited by jb78L-82; Dec 23, 2014 at 06:27 PM.
Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
You're not going to get 450rwhp with that combo going thru a t350 and 3500 converter.. Probably be lucky to get 350-375 rwhp. I wouldn't put much thought into chasis dyno numbers with an auto trans and a big converter....the converter will eat up a bunch of power on the dyno.
I do think a well built 383 with Cnc afr 195s, Vic Jr/750DP, 11-1 comp, and a good HYD roller will make 500-525 crank hp. You'll need 1 3/4" headers and a good 3" exhaust system too.
Personally I'd rather see some hand ported AFRs 210s done by a GOOD porter and end up in the 220cc range. Cam it to make peak power at 6500-6600 and do some work on the intake.. This I could see an honest 550hp out of.
I do think a well built 383 with Cnc afr 195s, Vic Jr/750DP, 11-1 comp, and a good HYD roller will make 500-525 crank hp. You'll need 1 3/4" headers and a good 3" exhaust system too.
Personally I'd rather see some hand ported AFRs 210s done by a GOOD porter and end up in the 220cc range. Cam it to make peak power at 6500-6600 and do some work on the intake.. This I could see an honest 550hp out of.
Le Mans Master
Joined: Oct 2007
Posts: 7,453
Likes: 976
From: RI, Now Franklin/Nashville TN
You're not going to get 450rwhp with that combo going thru a t350 and 3500 converter.. Probably be lucky to get 350-375 rwhp. I wouldn't put much thought into chasis dyno numbers with an auto trans and a big converter....the converter will eat up a bunch of power on the dyno.
I do think a well built 383 with Cnc afr 195s, Vic Jr/750DP, 11-1 comp, and a good HYD roller will make 500-525 crank hp. You'll need 1 3/4" headers and a good 3" exhaust system too.
Personally I'd rather see some hand ported AFRs 210s done by a GOOD porter and end up in the 220cc range. Cam it to make peak power at 6500-6600 and do some work on the intake.. This I could see an honest 550hp out of.
I do think a well built 383 with Cnc afr 195s, Vic Jr/750DP, 11-1 comp, and a good HYD roller will make 500-525 crank hp. You'll need 1 3/4" headers and a good 3" exhaust system too.
Personally I'd rather see some hand ported AFRs 210s done by a GOOD porter and end up in the 220cc range. Cam it to make peak power at 6500-6600 and do some work on the intake.. This I could see an honest 550hp out of.
600 Gross HP for 450 RWHP (and that would be on a dynojet type dyno-not a chance with a Mustang Dyno which is more accurate) in a C3 with that tranny and stall converter which is a tall order for a SBC motors like a 383 less than 400 cubes….
Last edited by jb78L-82; Dec 23, 2014 at 07:00 PM.
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Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
I'll be sub'd to see your progress on the new combo and the gains it makes.
Any chance of your car going to the drag strip before the combo change? I'm sure with 365 rwhp you are already in the high 11s@114 or so in decent air.
A GOOD set of heads/cam could gain you 100hp+.. That would be bottom 11s in your car at 3500lbs..
For me, drag strip numbers are the true indicator of power.. I bet yours is a runner as it sits.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
x2
Ive used that cam before it works well just not the "right" cam for what ya got.
To get 550chp out of a 383 will take much more than that
Have a 11:5-1 383 with a 230cc head 850 ported Team G solid roller with 30 deg more duration than your current cam Id be surprised if it made 550chp.
Ive used that cam before it works well just not the "right" cam for what ya got.
To get 550chp out of a 383 will take much more than that
Have a 11:5-1 383 with a 230cc head 850 ported Team G solid roller with 30 deg more duration than your current cam Id be surprised if it made 550chp.
Thread Starter
Cruising
Joined: Aug 2014
Posts: 14
Likes: 0
I have 10.5 psi compression with flat top pistons, probably loking at 6000-6500 max rpm, mainly street use, their is an article with a 383 with 294s magnum flat tappet with older afr 195 that didn't flow as well as the new ones and holley 750 making 540hp, they thought they could get more out of the 383 with bigger holley, I'm thinking the energy xs284s is similar to the 294s, combo will make 550 hp at the flywheel
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Last edited by Floatplanepilotguy; Dec 24, 2014 at 02:39 PM.
Le Mans Master
Joined: Oct 2007
Posts: 7,453
Likes: 976
From: RI, Now Franklin/Nashville TN
With a flat tappet cam even with AFR's, I would say about 425-450 Gross HP, at the most. The newer 195 AFR's with a pretty stout Roller cam, 11:1, and everything else optimised might get you 525 gross HP....I don't see 411 RWHP even with a real happy dyno with the current combo. As others have stated, drag strip times are the only real inidcator of power....
