383 with AFR 205
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Teching In
Joined: Dec 2003
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From: Orange Park
383 with AFR 205 Hello,
Long story short, two years ago I had Patriot heads(59cc ls6 style) on the car and it put down 451/418
. Wasn't very happy with it. Last year I put 205's(59cc) on it with a 90/90 combo and added a 9in ford rear end with 4.11's (had 4.10s in the stock) dyno'd at NLP both times around the same time of year and nothing else being changed it put down 497/460...alot better 
. I think it would have been in the 510 range if not for the 9inch and locker. With the back ground out of the way...I'm thinking of going to afr 225s now and was wondering if you guys think it's worth it? I'd like to do a back to back with 205s vs 225s. If you need anymore info ask away.
Thanks
Long story short, two years ago I had Patriot heads(59cc ls6 style) on the car and it put down 451/418
. Wasn't very happy with it. Last year I put 205's(59cc) on it with a 90/90 combo and added a 9in ford rear end with 4.11's (had 4.10s in the stock) dyno'd at NLP both times around the same time of year and nothing else being changed it put down 497/460...alot better . I think it would have been in the 510 range if not for the 9inch and locker. With the back ground out of the way...I'm thinking of going to afr 225s now and was wondering if you guys think it's worth it? I'd like to do a back to back with 205s vs 225s. If you need anymore info ask away. Thanks
Last edited by 99Transamman; Jan 30, 2006 at 08:34 PM.
I wouldn't worry with the 225s, unless they were the small bore and even then, I wouldn't spend money again to get them. Because you aren't spinning the 383 high enough and the cam doesn't make power high enough for the extra few cfm to make much of a difference up top. You'd lose throttle response and low end torque with the 225 and gain maybe 5-10rwhp up top, but be down probably 15-20rwhp avg over the entire run.
A ported FAST LSX90 will cut the flow off around ~300 anyway, so I'd rather have more flow at the lower lifts to make up for the "restrictor plate" effect at the top of the cam lift (which effectively nullifies any advantage the 225 has). But, you will still make more power with the 225 up top, but not enough to justify it imo.
A ported FAST LSX90 will cut the flow off around ~300 anyway, so I'd rather have more flow at the lower lifts to make up for the "restrictor plate" effect at the top of the cam lift (which effectively nullifies any advantage the 225 has). But, you will still make more power with the 225 up top, but not enough to justify it imo.
The debate has been raging on whether the switch to AFR small bore 225s is worth it on 346 or 383 already running AFR 205s. I will put this argument to rest by the end of this week when I swap my AFR 205 for some new AFR 225 hybrid heads. No other changes, just the heads. I do not expect to lose any power down low, but how much power I gain up high remains to be seen. I will dyno before, then after. Stay tuned.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
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Teching In
Joined: Dec 2003
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From: Orange Park
The cam is 240/244 113lsa .608/.612 got a nice little lope idles great. Car ran 7.02 at 100mph in humid florida. not my best but going this weekend 
I think i put down a little more than Tony
I think i put down a little more than Tony
Originally Posted by 99Transamman
I think i put down a little more than Tony
. oh, and its a pump gas friendly 10.9 CR with a mild solid roller.
Thread Starter
Teching In
Joined: Dec 2003
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From: Orange Park
He made more power on top end then my car(did the math 
)...5700 up. Is this because he had the bigger 225's or is it the solid roller setup. Tq I think I got him . Hope his 383 goes in soon so we can get some real numbers 
....I love dyno racing so much safer!!
)...5700 up. Is this because he had the bigger 225's or is it the solid roller setup. Tq I think I got him . Hope his 383 goes in soon so we can get some real numbers ....I love dyno racing so much safer!! 
I am in the process of building a 383 with a tr224/224 114 cam. My ? is how much am I leaving on the table? I have a set of ported 806 heads...yes the 97-98 head!!!! That made 384rwhp/382rwtq with my old 346. How much am I leaving on the table from my ported stock heads to say a ls6 cnc'd head (offered by the venders at $865) vs. a set of Afr 205's. Trying to see what direction I will go.....this is what it is going in www.ls1miata.net/gallery
Originally Posted by 99Transamman
He made more power on top end then my car(did the math )...5700 up. Is this because he had the bigger 225's or is it the solid roller setup. Tq I think I got him . Hope his 383 goes in soon so we can get some real numbers ....I love dyno racing so much safer!!
)...5700 up. Is this because he had the bigger 225's or is it the solid roller setup. Tq I think I got him . Hope his 383 goes in soon so we can get some real numbers ....I love dyno racing so much safer!!
My "air dyno" and stupid hours of calculations in my head has my 383 producing around 520 RWHP and 480 RWTQ installed in my C5 with a conservative solid roller and the "smallish" LG very loooong tube headers (which are actually ideal for a car like mine that spends a great deal of time on the street....I enjoy the crisp low end and throttle response the smaller header helps create at low engine speeds).
BUT....I will believe it when I see it as that is a pretty stout figure for a reasonably tame 383 build-up.
Hoping to share the chassis dyno results with you guys shortly.
Regards,
Tony
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Teching In
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From: Orange Park
Going this weekend if my new slicks get here in time . Last time I went was in middle of july very hot, heres the slip(right lane). I lost 3 mph in the 1/8th with all the heat. this was the first time i could run the 1/4(just put cage in)....so i think high 10s and 126ish should be no problem. Had to much tire also, 28s and 4.11s don't play well. So I went with 27s this time...We'll see
Tony....let me put my stock rearend back in and an electric water pump......and then I will have something for your solid roller .
. Last time I went was in middle of july very hot, heres the slip(right lane). I lost 3 mph in the 1/8th with all the heat. this was the first time i could run the 1/4(just put cage in)....so i think high 10s and 126ish should be no problem. Had to much tire also, 28s and 4.11s don't play well. So I went with 27s this time...We'll see Tony....let me put my stock rearend back in and an electric water pump......and then I will have something for your solid roller
. 
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From: harrisburg, pa
Originally Posted by turbotacoma
I am in the process of building a 383 with a tr224/224 114 cam. My ? is how much am I leaving on the table? I have a set of ported 806 heads...yes the 97-98 head!!!! That made 384rwhp/382rwtq with my old 346. How much am I leaving on the table from my ported stock heads to say a ls6 cnc'd head (offered by the venders at $865) vs. a set of Afr 205's. Trying to see what direction I will go.....this is what it is going in www.ls1miata.net/gallery
I have the Patriot LQ9 heads like yours although they were sent to Sunset for further work and bigger valves and the same cam as yours. My motor is a 395 though but I put down 489 and 470. I have a Fast 90 and electric wp. \Do you know what your Patriot heads were supposed to flow compared to the new ones?
Originally Posted by turbotacoma
I am in the process of building a 383 with a tr224/224 114 cam. My ? is how much am I leaving on the table? I have a set of ported 806 heads...yes the 97-98 head!!!! That made 384rwhp/382rwtq with my old 346. How much am I leaving on the table from my ported stock heads to say a ls6 cnc'd head (offered by the venders at $865) vs. a set of Afr 205's. Trying to see what direction I will go.....this is what it is going in www.ls1miata.net/gallery
A 224/224 114? I'd go a lot bigger. Your conservative cam choice will hurt power more than a GM factory head casting.
Ben T.
