AFR heads greatly out perform other manufactors heads hand d

[BenBaron]

I stand corrected, it looks as though its only the SBF heads that are @ 58cc chambers, wonder why....

[fastco]

Originally Posted by fastco

Hello from cross the pond the question we'd like to answer is do AFR's full CNC ported heads out flow & out BHP & torque other companies cyln heads with the same stated runner cc & full CNC port work done to them and do they out perform all others by a country mile as they would have us all believe.
This question has been raised 1,000's of times both side of the pond.
If we look @ AFR flow chart specs in there ads they certainly look to be a head of the pack . But are they really that much better for the price paid 100's of P/S more, then other manufactors heads is the big question.
A little tid bit of info for you chaps might shine a little light on why there flow #'s do exceed others heads AFR flow tests there SBC cylinder heads using a 4.500 dia bore not a 4.00 or 4.125 dia bore as we all know there is no SBC engine with a 4.500 bore & flowing heads using this 4.500 dia bore will greatly increase the flow #'s due to valve unshrouding & volume of the larger bore VS
a smaller STD Chevy bore of between 4.00 for 350 & 4.125 dia for Chevy 400 cid engines.
Now this test is not for bashing AFR at all they do surperb work & there heads a high standard race proven head ...... but the big question remains are there heads really that much better then the rest eg: Ed's Canfields , Brodix , Trick Flow , Pro-Comp RHS , Dart , World ect ect.
We 'll be testing AFR's 210 cc runner heads on our Chevy 383cid engine @ 10.4:1 comp with the same bottom end as the last engine dyno test we posted
That engine was loaded with Pro_comp 210cc runner heads made 477 BHP @ approx 6300 RPM & 469 ft lbs torque @ approx 4400 RPM.
Now we'll see how AFR's 210 cc heads compare to them, looking @ ARF flow charts there should be a great increasement in BHP & torque.... will see & post our findings & dyno's print out & DVD of dyno test.. just for fun.
Cheers! Dr,Dee

Hello mates we've just completed the dyno test on CRC members engine with ARF's 210 CC 100% ported heads & the #'s are in & the BHP & torque figures are in... The big question was do the AFR's wipe the floor with brand X 's 100% ported heads?
Well the answers to that is no & yes in my opion..... anyway will post full spec on both engines & leave the answer to that question with the facts presented speak for them slevles in regards to BHP &torque that both engines produced's & let the members decide who's won this battle.. ..... remember there are variables here but all in all it's was a close call.
Okay here is video of yesterdays dyno pull with AFR's 210 cc runner heads on Chevy 383cid engine with hyd roller cam... with very close specs as flat tappet cammed 383cid engine with brand X heads... right i'll post both dyno print outs & specs of both engine...... lets compare the REAL WORLD #'S not fudged or stretched #'s & beware this is only a key stroke way on dyno computer . Cheers! Dr,Dee
Go here for video of AFR heads loaded 383:

http://s4.photobucket.com/albums/y14...gAnch=imgAnch1

Photo of AFR head loaded engine:[IMG]http://thumb16.webshots.com/t/53/453/5/61/55/2804561550087216316GQzu
KF_th.jpg[/IMG]

Photo dyno print out of AFR head loaded 383

[Clarkson]

Whats the engine specs,looks comparable to my AFR 195cc spec 350 chevy.

[fastco]

Engine#1- Chevy 383cid engine with Pro-Comp 210 cc runner heads full CNC ported
Crank is Eagle 4130 forged 3.750 stroke , internal balance ,rods Scat 4340 forged I beam 6.00 long ,pistons Probe flat top 2 valve relief , rings are E/W moly race 1/16 comp , file fit type.
Cam is flat tappet hyd .539 lift , 244 dur @ .050 lift , lifters are Rhoads vari-duration & lift , hyd. anti pump up.Chain set Rollmaster billet gears 3 key.
Heads are Pro-Comp 210cc runners 100% CNC ported ,valves are 2.02 & 1.60 dia , Comp valve train , rockers are forged alum full roller.
Intake is Power+ Hurricane single plane & HMV " Super Sucker" carb spacer 2" high ,carb is Holley 750 CFM vac sec , full tricks by Dr.Dee . Fuel pump Mallory 140 Pro-Comp elect set @ 8 psi , Ignition is E/W billet alum race distributor, 63,000 volt out put coil , timing 28 degees mech all in @ 3800 RPM total timing 38 degrees
Ignition amp MSD 6AL system
Test results on Superflow 901 Dyno @ Gorden Race Engines USA.
MAX BHP @ 477.5 @ 6300 RPM , MAX Torque 469.6 ft lbs @ 4400 RPM

Photo of dyno print out:

Engine # 2- Chevy 383cid engine with AFR 210 cc runner heads 100% CNC ported , Crank assembly same as above.
Camshaft is custom grind hyd. roller cam .555 lift , 244 dur. @ .050 , lifters are Morel hyd. severe duty horizontal guide bars , Manton 4130 forged push rods custom length , chain Rollmaster billet gears 9 key crank , roller thrust button brg & torrigton brg thrust plate loaded.
Heads are AFR 210 cc runner 100% CNC ported 2.08 & 1.60 valves , Comp valve train ,rockers are forged alum. full roller .
Intake is Power+ air gap dual plane intake , Carb is B/G Demon 750 CFM double pump dual feed , recalibrated & set up by Dr.Dee . Fuel pump is Holley 110 GPH comp pump mechanical 7 psi .
Ignition is E/W billet alum race distributor 63,000 volt output coil, timing 28 degrees mechanical all in @ 3800 RPM total timing 38 degrees. Ignition amp
MSD 6AL system.
Test results on Superflow 901 Dyno @ Gorden Race Engines USA.
MAX BHP 452.7 @ 5800 RPM , MAX torque 464.6 ft lbs @ 4300 RPM

Photo of dyno print out:


Comparing the numbers we see that the brand X heads / Pro Comp 210 cc heads made 24.8 BHP more then the AFR heads & 5 ft lbs torque more then the AFR heads.
Taking into consideration on this test the differances in the two engines the Pro-Comp loaded engines intake was a single plane intake & the AFR loaded engines intake was a dual plane intake. ( the single plane intake feeding more A/F volume then the dual plane intake)
AFR heads valve dia 2.08 & 1.600 & Pro-Comps valves 2.02 & 1.600 dia.
The camshaft in the Pro Comp engine is std flat tappet cam , the AFR used a hyd roller cam & lifters, so there are advantages & disadvantages with both engines.... the the overall spead in BHP & torque was not that large even with these differances. The over spread in total costs of parts for these two engines
was huge eg prices of AFR 210's VS Pro-Comps 210 heads , prices of std hyd cam & lifters VS custom grind hyd roller cam & lifters & thrust kits & custom
pushrods.

To be fair i'd conclude if the AFR heads were loaded onto a all out race engine with very high comp & tunnel ram intake & 1.750 dia comp headers they would out perform the Pro Comp heads but in a street & track application engine such as these the gains for the dosh spent are questionable.
My to cents / pents
Dr,Dee
PS: both engines were dyno'd with the same header system Hooker 1.625 dia headers 33 inch tube lenghts.

[Clarkson]

Daryl,there not really the same motors are they??,the 2 differant cams and intake manifold can easlly make 24hp extra on a 383 motor??

PS cheers for the leads mate!:thumb:

Here are my figs for a 350chevy with 195cc heads.

[mikey]

Originally Posted by Clarkson

Daryl,there not really the same motors are they??,the 2 differant cams and intake manifold can easlly make 24hp extra on a 383 motor??

PS cheers for the leads mate!:thumb:

Here are my figs for a 350chevy with 195cc heads.

Over 50% increase in vapour pressure with denser charge is also an issue which throws it out the window.

Looking at your figures the pro comp will outperform the AFR in a street race and in a drag race I am not sure the hotter engine would make up the torque and HP difference. Certainly the characteristics are better suited to the track with high RPM's as the milder engine has it in virtually all areas by the looks of it.

Unfortunately there is only one way to compare and that is by changing heads on the same engine and running when the air pressure is virtually identicle as you can easily get 10 BHP in that. By the way I think much of the torque difference could be ironed out using 190 runners, it will give a better signal on a 383 at the lower rev range and theres always a benefit in higher gas flow speeds.

Interesting reading though.
All the best
Mike

Ha-ha!! A brilliantly unscientific comparison with "wetted finger in the air" conclusions - love it! Totally pointless and yet strangely intriguing at the same time

[dave]

Straight over my head.
It does look like the cheaper engine makes more power. Sadly I don't have those spec heads on my DeskTop Dyno but smaller runners always seem to make more power. Maybe different with an 8,000rpm cam,(But not much use without 8,000rpm crank , rods, pistons etc.) who knows?

[fastco]

Originally Posted by smash

Ha-ha!! A brilliantly unscientific comparison with "wetted finger in the air" conclusions - love it! Totally pointless and yet strangely intriguing at the same time

Hi mate you've obviously met Joe Venolla & Grumpy Jenkins & Smokey Yunick ... in your travels.. they all were not scientist but master engine builders & designers & wet finger tuners of T/F 6000 BHP engines & 700 + BHP NASCAR engines in there day, see NHRA & NASCAR world record books & see how good a wet finger can be with 40 & 50 years practise.. ha ha great fun mate...
You missed the point mate....regardless of the induction or cam differances the AFR's do not "wipe the floor "will brand x's heads & they should have with a hyd. roller cam & BG Demon race carb as an advantage over the Pro- Comp engine .
The differance between the two engines BHP & torque in the real world & not in a scientific labratory is hardly worth chat'n about.... but the dosh spent to produce the #'s in both engines is well worth a good long chat


Cheers! Dr,Dee