Thanks for clearing that up John. I wasnt sure thats why I asked. As I said earlier I havent seen what the guy in ballarat can do so i cant comment on what he uses to provide the internal finish so this is unknown. I will spray some white paint down my ported manifolds on monday so we can see how close to you tested ones I have managed to get by eye. That should be interesting. Lastly, The amount of HP they will cope with is not that much of a problem. The issue is to reduce the air flow resistance to a minimum through the lower plenum, heads, exhaust manifold and dumps/exhaust. so that the only limiting factor in any installation is the turbos and the amount of air they can pump. In an ideal situation with minimal air resistance you should be able to get to the point with GT28R's that driving them harder than 18 PSI will give no more power as the air flow through them cannot be increased further. Hence our phone discussion a few months ago about the aims for my cylinder heads I want to send up for you to work on for me. The bigger valves, high lift cams etc etc I have for them should mean a major restriction is removed and be closer to removing a lot of flow resistance from the system. This manifold discussion is closely aligned with that thinking and for me the last part of the jigsaw in getting max power out the turbos at low boost.
i had this conversation with a mech eng at work just about 2 hrs ago the way i see it, the air circuit is a long path and the resistance to flow all along that path adds up if one section is very restrictive, then improving the flow on another section won't see a huge benefit, but it will still be there just not as noticeable so if there is no single excessively restrictive section, then by improving flow on any other part will still make an improvement and it will be more noticeable that was my understanding, and he pretty much agreed with that i think that if you can make 400kW on X manifold, then you can make 400+kW on Y manifold if Y manifold flows better than X and if someone else makes 300kW with X manifold, then they will make 300+kW on Y manifold because there will be more air flow (how much more depends on how significant the restriction of X was) i'm not saying that this is spot on correct, but i'm happy to learn and be corrected
Thats pretty much spot on MaTTz. Remember just because the pipes are larger in diameter doesnt mean they will flow more, careful consideration needs to be given to the actual flow direction as it travels through the runners, Tektrader mentioned the buildup in the stock mani's to help achieve this result. Flow is directly related to restriction and design. As John UAS mentioned the airflow can actually bounce off the back wall of the central runner and create excess turbulence which results in less flow and this will be something to keep an eye on while you go throug hthis process with caster guys from the foundry. less restriction and good design = more flow more flow = more power more power = more fun Will keep an eye on this one it has me intrigued as to the end result. Good Job thus far
OOPPPS This not only applies to just the manifolds, the same principal applies to the whole intake/exhaust system. So if you get these things made you will have to follow on with the other necessary items before the full potential can be realised.
Yep all good Less restriction means more power and less heat. We are all on same or similar page. My pint is not all after market products are better is more my point although this one looks good as mentioned. I don't just mean looks either as I am not into looks but the fact that it is cast so won't crack, larger volume and if as even as factory or better then plenty to imprpove on. Keep in mind the factory ones are terribly for flow. The most restrictive runner flows about 99cfm standard and after numerous tests of angles of flow and trial and error of porting and extrude hone James from "Abrasive flow gets them up to 150cfm now. These are the figures below from UAS site. BEFORE AFTER 123 173 99 146 139 186 136 177 118 168 139 186 Compared Zeds to GTR's which flow better and more even stock and after extrude honing. Stock RB26 Manifolds 155.7 138.2 150.1 UAS Extrusion Honed Manifolds 182.7 167.4 179.3 Mainly as GTR's have more room for smoother and longer runners.
Hey JP, what lift are those figures attained at? Here are the flow figures for the Mike Smith manifolds, they show: Stock:100.6 Mike Smith:160.5 That is a flow test taken off middle cylinder at 0.4" lift. http://www.twinturbo.net/net/viewmsg.aspx?forum=general&msg_id=1772731
Results of all tested: Stock:101 hand ported stock:101.8 extrude honed stock:110.1 Greg Dupree(iconnel):150.8 Greddy tubular:159 Pentroof tubular:165.8 Mike Smith (cast)160.5
thats pretty vague numbers mate.. was that a particular runner? i find it hard to believe that hand ported only increased flow by .8.. i mean what did they do.. spit and polish em?
The figure I am always bemused they didnt do, was heavily hand ported and extrude honed stock manifolds. Whats the point of doing one or the other?? I vaguely seem to remember they tested the centre runner in these tests. If they got up to 140CFm in the test set for hand ported and honed. I wouldnt bother with the other manifolds.
yes, as stated in my first post, middle runner. Check the link for the numbers. http://www.twinturbo.net/net/viewmsg.aspx?forum=general&msg_id=1772731
I got some info off Andrew from Specialised power porting (Ballarat) a while back; have heard good things BEFORE PORTING AFTER PORTING 1. 153 cfm 1. 192 cfm UP 39 cfm 2. 123 cfm 2. 154 cfm UP 31cfm 3. 170 cfm 3. 212 cfm UP 42 cfm 4. 151 cfm 4. 191 cfm UP 40 cfm 5. 130 cfm 5. 172 cfm UP 42 cfm 6. 160 cfm 6. 196 cfm UP 36 cfm Got some pics too if anyone is interested. Col
Flow figures? Figures and stats may be right but what is the whole story and can they be relied on. I don't want to sound negative and I know some don't want to know the facts or think I am knocking a competitor?s product. Tektrader I am with you and I question these figures actually with stock and ported being only .8 of what ever test was done. I assume it was a flow bench test and 25 or 28 inches of water but who knows. I know we have independently tested and challenged flow figures of power ported plenums for zeds and have found to be totally false both by them self and more importantly bolted up to a head. JT the figures are all at stock lift which is not much and zed benefit greatly form more lift with aftermarket cams. We used to promote power ported plenums and bigger throttle bodies until we did flow test and found only makes 7 to 9 CFM which is not much. My zed runs stock plenum and throttle body and makes 438rwkw. Might have made a few more rwkw with larger thottle bodies and plenum but not worth the money. Hence why I am questioning these and the expence and most won't need them like larger throttle bodies. Until tests are done we won't know maybe they are much better and would want to be for 2k. Some think I just knock competitors well if you do a search you will see I have stated that the power ported plenums and larger throttle bodes are not worth it and we sell them. Boli! Very interested in pics of the product but more of the equipment that tested it and did the sand blasting or porting.
John, Cant really tell you if they can be relied on or not, i know people who have had work done by Andrew and they have been very happy,and have only ever heard good reports about his work. but as for a VG30 manifolds i dont know anyone who has used them, sorry. Anyway here is a bit of info and some pics, if you would like any other info im sure Andrew would gladly email it to you as he did me, but i dont know how to post it up. Andrew Sanders Ph: (03) 53418028 Mob: 0438 418028 spp@qonline.com.au Australian Abrasive Flow Porting Technology The Specialised POWER PORTING Process was developed to increase airflow in inlet and exhaust manifolds for significant horsepower gains. The Power Porting process involves forcing an abrasive media through the entire manifold. The internal passageways are enlarged and the rough, power robbing, cast surface contours are dramatically improved. Power Porting is a fluid dynamics process that removes and polishes metals only where airflows, an ability those traditional methods of porting cannot see let alone reach. This has made late model long runnered fuel injected manifold improvements a real success along with traditional fuel running manifolds. As the abrasive media is forced through the manifold runner the areas that restricts its flow is abraded, which means on a 90-degree bend, example (6 cyl. Holden red) virtually no metal is removed from the long radius, this allows greater velocity in the bend, thus keeping fuel in an atomized state and holding it in suspension, allowing for better fuel distribution to cylinders. As important as air flow increases is the ability of the Power Porting process to balance flow. Manifolds are flow tested (CFM) the weakest runners are Power Ported more than the rest of the runners to achieve better air flow balance between cylinders, which results in a more efficient engine that will have less thermal stresses and run more smoothly and economically when tuned correctly. Airflow improvements in various manifolds up to 30% have been achieved allowing for greater horsepower potential. Hope this helps. Cheers, Col
Looks good` They would flow much better than factory ones but ? On flow figures. I am thinking of getting a sand or grit blasting machine to do similar as cheaper way of doing it and plenums on GTR's as well as zeds etc. I found flow figures we tested to be totally wrong, as in way optomistic. I questioned Andrew on this a few times. If you are local go check it out and see the sectret machine he uses as he won't send me pics as said it is a secret. Abrasive Flow Engineering gets the most restrictive runners up by as much as 50%.
Im sure some people will still differ Method This info has been posted before in comparisons and some people still make the same claims regarding ported and flowed stockies
Interesting and seems thorough Looks good and factory ones can be improved on and looks like someone has done it. My point was are they necessary and what tests. Now someone shows these tests show they are good and appears to be thorough test and the shoe fits as they should flow better. Next question I raised is it worth $2000 for big hp cars yes but for others and yet to be proven will it make more power and how much more on low hp cars.
guys i've been distracted on this one i had booked in a meeting with the pattern maker at Veem Engineering www.veem.com.au or do a search on veem if that's not their site, but they seem like a pretty technically good/experienced place anyways, i didn't rock up andrew has convinced me to buy a motorbike, and a couple of days ago i bought one so it's a case of "doing too many things at once" because that bike might take some work to get registered then i might wanna bore it out to 300cc or something (it's a 2 stroke 250cc) however, given the recent info that the MSP's are going to be $1k US, that would make a perfect mould for the pattern maker to work with, much less work involved and costs would be lower i think it would be great if someone else took up the batton and ran with this one, cos i'm goign to have to hand it over to someone else :zlove:
