How Much HP Will it make??
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Guess its better to have the shortblock/CI to start with can always add heads later.
Look up tpi421vette he will get you a smokin deal on a set of AFRs, may change your mind.
Look up tpi421vette he will get you a smokin deal on a set of AFRs, may change your mind.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Scott
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Even vortecs would be a radical improvement, but you'd need another intake.
I think that cam comes in at just under the max lift for Vortec heads.
You'd probably be in about $800 more to go to vortec heads.
I think that cam comes in at just under the max lift for Vortec heads.
You'd probably be in about $800 more to go to vortec heads.
Le Mans Master
Joined: Oct 2010
Posts: 6,930
Likes: 842
From: melbourne florida
2023 C3 of the Year Finalist - Modified
wow! i never see this much agreement on this forum, i agree the heads are killing this. they barely flow enough for a 350 and your adding all the volume of the longer stroke. the cam also is mild for a 350 which makes it milder on a 383. I'm not sure with this combo his torque numbers will be substantially better than stock. unfortunate.
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
http://www.speedwaymotors.com/Flo-Te...lug,25118.html
740 bucks, and you don't need a new intake manifold or valve covers. How much are you spending to recondition those raggedy old heads? My grandpappy would have called that being a penny wise, but a dollar foolish.
Scott
740 bucks, and you don't need a new intake manifold or valve covers. How much are you spending to recondition those raggedy old heads? My grandpappy would have called that being a penny wise, but a dollar foolish.
Scott
Racer
Joined: May 2013
Posts: 421
Likes: 6
From: Chicago IL
Be weary on buying cheaper heads (trust me). 
Make sure all the valves seat right if you buy them assembled and check them over 100%. I can tell you from my nightmare, cheap heads are aimed at those that just slap them on their cars and don't know any better. That being said, I did look at the Flo-Teks that Scotty is pointing out - but very little reviews on their use.
Make sure all the valves seat right if you buy them assembled and check them over 100%. I can tell you from my nightmare, cheap heads are aimed at those that just slap them on their cars and don't know any better. That being said, I did look at the Flo-Teks that Scotty is pointing out - but very little reviews on their use.
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
Jartanyon I agree, but I would love to know what heads you picked that were crap... a lot out there for sure, but it is still nice to get a report on the bad ones so as the rest of us stay away from them:-)
Racer
Joined: May 2013
Posts: 421
Likes: 6
From: Chicago IL
I went through 3 sets of heads that were supposed to be awesome to the "maxx" for the price…not my experience at all. Perhaps someone else will have a different experience, but for me…three strikes and you are out!
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Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
promaxx??? we all need to know whats bad, so we can stay away from them as a whole... bad products need the light shined on them so the rest of us stay away from them so we dont get screwed as well... thx:-)
Racer
Joined: Feb 2012
Posts: 261
Likes: 3
From: Clawson Michigan
I believe I purchased the same heads as jartanyon but in bare form and had the same results. Promaxx patriot Alabama cylinder head every seller has a different name for them. Mine have became garage wall art.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Set the timing a little retarded ( like me ) and take it out for a spin right away, don't sit there and rev it up etc. Take it out and seat the rings,take it to 3000RPM and let your foot off the gas and let the engine slow you down, then take it 4000 RPM twice, same deal let the engine slow it down, Then take it 5000RPM and your done. I take roller engines to 5-6000RPM five minutes after I start them. Check for leaks
and let er rip.
To the OP, I did the same thing as you are planning to do, only flat tops with about 9.5 compression and a CC270H cam. I had them clean up the 882's and I was not impressed with the result. l I put World Sportsman II's on the engine and it really woke it up. Your not going to see any more than 200HP and change on a chassis dyno with the 882's
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Race Director
Joined: May 2003
Posts: 10,956
Likes: 409
From: California
Hey Paul, can't wait to hear and see it running, prime it and let er rip. All the roller engines (solid) I have built I double and triple check all the hoses, especially to the carb or FI in your case and electrical and fire it up.
Set the timing a little retarded ( like me ) and take it out for a spin right away, don't sit there and rev it up etc. Take it out and seat the rings,take it to 3000RPM and let your foot off the gas and let the engine slow you down, then take it 4000 RPM twice, same deal let the engine slow it down, Then take it 5000RPM and your done. I take roller engines to 5-6000RPM five minutes after I start them. Check for leaks
and let er rip.
Set the timing a little retarded ( like me ) and take it out for a spin right away, don't sit there and rev it up etc. Take it out and seat the rings,take it to 3000RPM and let your foot off the gas and let the engine slow you down, then take it 4000 RPM twice, same deal let the engine slow it down, Then take it 5000RPM and your done. I take roller engines to 5-6000RPM five minutes after I start them. Check for leaks
and let er rip.
The FI is new to me, it controls my timing as well, and my distributor is locked in at 30* .... all this is new to me, ,,, so used to carburetors and standard type of timing..
my main engine guy says the same thing, Take it out and seat the rings,take it to 3000RPM and let your foot off the gas and let the engine slow you down, then take it 4000 RPM twice, same deal let the engine slow it down, Then take it 5000RPM and your done
CHINA
Racer
Joined: Sep 2013
Posts: 417
Likes: 11
From: Brigham City Utah
I thought long and hard about a rebuild, finding new heads, labor, machine shop time, parts and what not.....I found this a very affordable option.
http://high-performance-engines.com/...duct_Code=HP89
ATK also has a 383 Stroker as well.
Karsten
http://high-performance-engines.com/...duct_Code=HP89
ATK also has a 383 Stroker as well.
Karsten
