AFR 205's make big power
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AFR 205's make big power
Well, after a looonnngg time fooling around with exaust solutions I finally ended up with a set of DRM cutouts. Thus the resurrection of my car is complete.
I went to ECS and did my final PE and timing tweaks but didn't have enough time to finish and thoroughly tweak the AFR and timing for peak torque and hp. However, I'm fairly close with about 10/10 on the table, maybe a scouche more?
I have to thank Doug, (Thanks Doug! ) for pulling an alternator out of his back pocket when I killed mine on the dyno. And also to Mike for popping the old one out and the new one in so fast I didn't even know it was done!
Tony Mamo came through again. Thanks again Tony. Putting the potato in the exhaust was key, but I had to use 4 for the TI tips.
Below are the numbers and the specs are in my sig. This is with a stock water pump, 4:10's, and Kooks cats (Magnaflows - I think). The car drives around town like stock, but runs like a 'scalded dog' or a 'raped ape' or whatever when I push the long thin pedal on the right side.
The AFR is very flat at 13.1:1 from the onset to the rev limit, hence the lower than optimum tq/hp levels.
I went to ECS and did my final PE and timing tweaks but didn't have enough time to finish and thoroughly tweak the AFR and timing for peak torque and hp. However, I'm fairly close with about 10/10 on the table, maybe a scouche more?
I have to thank Doug, (Thanks Doug! ) for pulling an alternator out of his back pocket when I killed mine on the dyno. And also to Mike for popping the old one out and the new one in so fast I didn't even know it was done!
Tony Mamo came through again. Thanks again Tony. Putting the potato in the exhaust was key, but I had to use 4 for the TI tips.
Below are the numbers and the specs are in my sig. This is with a stock water pump, 4:10's, and Kooks cats (Magnaflows - I think). The car drives around town like stock, but runs like a 'scalded dog' or a 'raped ape' or whatever when I push the long thin pedal on the right side.
The AFR is very flat at 13.1:1 from the onset to the rev limit, hence the lower than optimum tq/hp levels.
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Well I certainly can't wait to see how my upcoming 402 does with my afr 205's and g5x3vII cam being reused in it. Close in specs to you bro.
Congrats on your results. Scalded dog comment is too funny.
Congrats on your results. Scalded dog comment is too funny.
#6
I did do some light porting and aggressive combustion chamber work (to take advantage of his larger bore motor) on Roger's 205 heads as well as provide him with a ported FAST and ported LS2 TB combo. Also, Roger is extremely detail oriented and spent alot of time ensuring everything was spot on with the build (valvetrain geometry etc.). Its just another very optimized build with the right parts and attention to detail....much like a few of the combinations I have built or been very involved in the past. To be honest I was a little surprised about the horsepower myself but certainly very pleased. When Roger and I discussed this package (at great length I might add), my guess was closer to 515 RWHP and a ton of area under the curve.
Regarding a DynoJet and a DynaPack dyno, trust me the read very similar UNLESS you run heavy aftermarket rims and tires. With a Dynapack that variable is eliminated as the dyno bolts directly to the wheel hubs. With my reasonably light 10.5" Z06 rims and lighter Nitto DR's (tire/rim combo around 48 lbs) the two dyno's were virtually identical, but I have seen some combo's dyno 10 or so RWHP more on a Dynapack that ran heavy rim/tires combinations (which would cost you power on a DynoJet or any typical wheel dyno)....some of them over 60lbs each. Also, for anyone questioning these results, look at the torque which is what this dyno is actually measuring (like a flywheel dyno would)....its not unusually high at all for this combination. The key to the big power is that the optimized set-up related to its airflow and breathing ability allowed that torque curve to hang on much longer at higher RPM and thats how the big power came to be....purely a mathmatical function of the torque produced and the RPM turned. When you see a 346 make 400 RWTQ at 3000 RPM's and see an abnormally high power curve then you start to question things as it would border on impossible for an engine of that displacement to produce that much torque at that RPM.
Congrats Roger....it was a long time coming but worth the wait.
BTW, the best part about this combo is the insane throttle response, tip in power, and overall SOTP from the small heads. The car feels even faster than than the stout numbers you guys see at WOT because the part throttle of this combo would "feel" like a much larger engine was actually installed.
Good stuff....
Regards,
Tony
Regarding a DynoJet and a DynaPack dyno, trust me the read very similar UNLESS you run heavy aftermarket rims and tires. With a Dynapack that variable is eliminated as the dyno bolts directly to the wheel hubs. With my reasonably light 10.5" Z06 rims and lighter Nitto DR's (tire/rim combo around 48 lbs) the two dyno's were virtually identical, but I have seen some combo's dyno 10 or so RWHP more on a Dynapack that ran heavy rim/tires combinations (which would cost you power on a DynoJet or any typical wheel dyno)....some of them over 60lbs each. Also, for anyone questioning these results, look at the torque which is what this dyno is actually measuring (like a flywheel dyno would)....its not unusually high at all for this combination. The key to the big power is that the optimized set-up related to its airflow and breathing ability allowed that torque curve to hang on much longer at higher RPM and thats how the big power came to be....purely a mathmatical function of the torque produced and the RPM turned. When you see a 346 make 400 RWTQ at 3000 RPM's and see an abnormally high power curve then you start to question things as it would border on impossible for an engine of that displacement to produce that much torque at that RPM.
Congrats Roger....it was a long time coming but worth the wait.
BTW, the best part about this combo is the insane throttle response, tip in power, and overall SOTP from the small heads. The car feels even faster than than the stout numbers you guys see at WOT because the part throttle of this combo would "feel" like a much larger engine was actually installed.
Good stuff....
Regards,
Tony
Last edited by Tony Mamo @ AFR; 07-11-2008 at 02:23 PM.
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#8
I thought that for a motor with those cubes (402), it would be ideal to go with the AFR 225's. IS this incorrect? Why did you go with the 205's over the 225's, and what woul be the advantages\disadvantages of each head?
Not questioning your judgement, more so just looking to learn a bit and understand why you went the direction you did, and the results of that decision.
Not questioning your judgement, more so just looking to learn a bit and understand why you went the direction you did, and the results of that decision.
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I thought that for a motor with those cubes (402), it would be ideal to go with the AFR 225's. IS this incorrect? Why did you go with the 205's over the 225's, and what woul be the advantages\disadvantages of each head?
Not questioning your judgement, more so just looking to learn a bit and understand why you went the direction you did, and the results of that decision.
Not questioning your judgement, more so just looking to learn a bit and understand why you went the direction you did, and the results of that decision.
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Hey guys, Sorry for not jumping back on until now. I posted this late Thursday night and was traveling all day yesterday. I know there is at least 10/10 left on the table, and I plan on addressing that after the summer and after the motor has had a chance to break in a little more.
The specs on the motor and combo are as follows:
LPE 403 - forged with a Dragonslayer crank, Compstar Rods, and Mahle pistons. - tried to keep it lightweight. stock LS2 waterpump, LS2 timing chain and gear. Comp XER Grind 242/242 .610"/.610" 114LSA installed +2. Cadillac racing lifters, 7.375" Comp pushrods, Yella Terra UL rockers, installed with .080 shims (best wipe). .030" Cometic gaskets (slugs were .010" in) LPE high volume oil pump.
AFR heads worked by Tony Mamo, AFR 8019 springs shimmed. BTW, these heads were beat up from my previous build. One chamber was toast with the washer that fell in still in the head. So he had to reweld them and resurface them. I couldn't see where the damage was after I got them back. I could only detect a slight discoloration where the welds went in. This also brings me to the reason for going with 205's. I had them and didn't have to invest in a new set. Also, for less than the cost of buying a new set of 225's I got a great chamber rework and porting job from one of the best. Also I discussed with Tony the benefits of the 205's vs. the 225's, and what I wanted the car for. Since it isn't a drag car and I was planning on using it for fun and some HPDE's we agree'd that having nasty throttle response coming out of a corner or spanking some rice stoplight to stoplight was more important than absolute top end performance. Tony nailed it with these heads and cam combo.
VaraRam B2 - VaraRams typically make a little less power sitting still on the dyno as they are designed for pushing air, not pulling it. - This is also debateable.
Haltech Airbridge modified to mate between the VaraRam and a PowerMax 100mm MAF (uses the new Hitachi MAF element).
Nick Williams 90mm TB - I'm thinking of having Tony port this too. Problem is, he's so damned busy! Tony Mamo ported 90 mm FAST.
Kooks 1 7/8" into 3" xPipe with cats to 3" mid-section to Z06 Ti's.
The clutch and PP are a Textraila OZ700 and billet steel flywheel.
The rear is a built 4:10 from ECS.
So the power was made through cats, TI's, stock water pump, and 4:10's.
And as far as throttle response goes Tony is right, it's instantaneous. I cannot stab the throttle in 1st or 2nd or I hit the rev limiter almost instantly.
MY daughter works for Lamborgini and has been in the new LP560 a bit. When I took her out in my car she had to admit it was faster. Made me feel really good, since she's become a bit of an elitist
The specs on the motor and combo are as follows:
LPE 403 - forged with a Dragonslayer crank, Compstar Rods, and Mahle pistons. - tried to keep it lightweight. stock LS2 waterpump, LS2 timing chain and gear. Comp XER Grind 242/242 .610"/.610" 114LSA installed +2. Cadillac racing lifters, 7.375" Comp pushrods, Yella Terra UL rockers, installed with .080 shims (best wipe). .030" Cometic gaskets (slugs were .010" in) LPE high volume oil pump.
AFR heads worked by Tony Mamo, AFR 8019 springs shimmed. BTW, these heads were beat up from my previous build. One chamber was toast with the washer that fell in still in the head. So he had to reweld them and resurface them. I couldn't see where the damage was after I got them back. I could only detect a slight discoloration where the welds went in. This also brings me to the reason for going with 205's. I had them and didn't have to invest in a new set. Also, for less than the cost of buying a new set of 225's I got a great chamber rework and porting job from one of the best. Also I discussed with Tony the benefits of the 205's vs. the 225's, and what I wanted the car for. Since it isn't a drag car and I was planning on using it for fun and some HPDE's we agree'd that having nasty throttle response coming out of a corner or spanking some rice stoplight to stoplight was more important than absolute top end performance. Tony nailed it with these heads and cam combo.
VaraRam B2 - VaraRams typically make a little less power sitting still on the dyno as they are designed for pushing air, not pulling it. - This is also debateable.
Haltech Airbridge modified to mate between the VaraRam and a PowerMax 100mm MAF (uses the new Hitachi MAF element).
Nick Williams 90mm TB - I'm thinking of having Tony port this too. Problem is, he's so damned busy! Tony Mamo ported 90 mm FAST.
Kooks 1 7/8" into 3" xPipe with cats to 3" mid-section to Z06 Ti's.
The clutch and PP are a Textraila OZ700 and billet steel flywheel.
The rear is a built 4:10 from ECS.
So the power was made through cats, TI's, stock water pump, and 4:10's.
And as far as throttle response goes Tony is right, it's instantaneous. I cannot stab the throttle in 1st or 2nd or I hit the rev limiter almost instantly.
MY daughter works for Lamborgini and has been in the new LP560 a bit. When I took her out in my car she had to admit it was faster. Made me feel really good, since she's become a bit of an elitist
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I thought that for a motor with those cubes (402), it would be ideal to go with the AFR 225's. IS this incorrect? Why did you go with the 205's over the 225's, and what woul be the advantages\disadvantages of each head?
Not questioning your judgement, more so just looking to learn a bit and understand why you went the direction you did, and the results of that decision.
Not questioning your judgement, more so just looking to learn a bit and understand why you went the direction you did, and the results of that decision.
I went very heavily on Tony's recommendation. I believe that velocity is more important than volume when building NA power. So we talked about matching the heads with the cam. Also, Tony opened up the chambers for the 4" bore which also unshrouded the valves a bit. I've read you can use about 10 degrees more duration on a 402 than with a 347 so the cam really isn't that big. Also we went with a 114 LSA to keep the overlap down for a wider torque curve, again adds to the throttle response.
What I suggest to anybody contemplating building a new combo is to really be honest about what you want the car to do. Making big numbers is easy to do, but it costs a lot of money and why spend it twice? When I was forced into redoing my motor my head was spinning with possibilities. I had been doing a lot of research on these boards and learned a lot, but I've learned that a little knowledge can be dangerous. Also, you can't replace experience, so I contacted the guy I thought would be the best to redo my heads, Tony, since he designed them. I then learned he's been building motors for a long time and has thousands of hrs working on LS1's, etc. So I started asking questions and soon realised I was talking to an experienced engine builder. The outcome was a car that is pretty snotty for a budget build, it's reliable, and drives like stock around town, with no surge, etc. I can take my wife out to dinner in it, have a converstion with her while listening to the radio, and give the keys to the valet and he can drive it and park it. Then on the weekend I can put the CCW's on it and take it to the track and have a good showing.
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After reading about your success I am very excited about my upcoming results doing a 402 with afr 205's and a similar cam. I'll most likely be using Mahle pistons and callies parts too.
How big are your combustion chambers bro ?? Mine were milled to 59cc.
What size valves you got in those heads ?? What compression are you running ??
How big are your combustion chambers bro ?? Mine were milled to 59cc.
What size valves you got in those heads ?? What compression are you running ??
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The combustion chambers were made larger to accomodate the 4" bore. I'm not sure what Tony did there other than I was told to use 4.130" bore gaskets. I'm pretty sure they were milled to 58cc's to get an SCR of 11.5:1. I'm using the oem size valves for the 205's, the 2.02" and 1.60". The intakes are hollow shaft Ferrea's.
I think the 3.42's will show ~12-15 more hp/tq than the 4:10's. Best of luck on meeting your goals.
I think the 3.42's will show ~12-15 more hp/tq than the 4:10's. Best of luck on meeting your goals.
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Now that I've experienced it I have to agree. I was a little skeptical at first but the economics made sense. I think the cam matches the heads and cylinder volume very well which is why it ended up where it did.