artinist Posted December 8, 2003 Report Share Posted December 8, 2003 new cylinder head, springs, valves $500 professional port job $500 one step closer to taking down supercharged M3s, priceless -------------------------------------------------------- anyway, its a bit of an odd port job, at least it seems to me. most of the effort has gone into reshaping both the intake and exhaut port radius and especially the combustion chamber area than the valve stem area. I dont know much about porting so I will have to trust that its done correctly vs. what I would and have seen done with the valve area. the porter explaing that this is the proper way of improving flow and combustion in a high boost engine and I take his word for it since he does all the heads for my buddies shop who spits out a 600hp corvette a week. lets see if his magic touch will continue here. it was too much work to convert the flow bench from a chevy setup to fit this head but I may be able to get it done at a later time. http://home.earthlink.net/~artinist/images/marnelhead/chamber1.jpg http://home.earthlink.net/~artinist/images/marnelhead/chamber2.jpg http://home.earthlink.net/~artinist/images/marnelhead/exhaustport1.jpg exhaust port http://home.earthlink.net/~artinist/images/marnelhead/intakeport.jpg intake port Link to comment Share on other sites More sharing options...
Joel Posted December 8, 2003 Report Share Posted December 8, 2003 Those chambers were hit to hard with the grinder. Go get some 3m Scotch bright pads and smooth them out. Joel Link to comment Share on other sites More sharing options...
Boosted_One Posted December 8, 2003 Report Share Posted December 8, 2003 Looks nice Art! Those ports look a lot like my ports. I paid $450 with flow numbers so your guy was in the ballpark. Link to comment Share on other sites More sharing options...
chiplee Posted December 9, 2003 Report Share Posted December 9, 2003 nice job getting good pics. Â looks like alot of thick metal around the edges. Â I don't know how much can be taken off but did he provide you with any flow data? Â would be nice to compare with mike's. edit: oops nevermind, guess you already answered that. Link to comment Share on other sites More sharing options...
artinist Posted December 9, 2003 Author Report Share Posted December 9, 2003 good idea joel, i will go over it with 1500 sand paper and then scotchbrite. Link to comment Share on other sites More sharing options...
Lizzord30 Posted December 9, 2003 Report Share Posted December 9, 2003 Man thoes chambros look sweet very nice job on that, cant tell he do alot with the ports, deff better but no major hoging, not that it nessarly needs to be. A flow sheet would be awsome. Link to comment Share on other sites More sharing options...
shift1313 Posted December 10, 2003 Report Share Posted December 10, 2003 what do you guys think about the intake ports. i know you want the manifold not polished so you have better homogonization, but what do you guys think about the ports, do you want polished ports? or is a bit rough better for combustion? ps, the head looks good:) Link to comment Share on other sites More sharing options...
Technology Posted December 10, 2003 Report Share Posted December 10, 2003 would it cause hot spots if it weren't really smooth? and can't you have the exhaust ports really smooth, but not the intake. Link to comment Share on other sites More sharing options...
ZPI28 Posted December 10, 2003 Report Share Posted December 10, 2003 Yes you want the exhaust polished good, and intake ported good. Hot spots would be caused if there were some larger casting marks that werent taken off. Those chambers look good, wonder how much that effects the CC, what comp. are you going to be running? Steven Link to comment Share on other sites More sharing options...
GoldNBlack Posted December 10, 2003 Report Share Posted December 10, 2003 WOW, hard to tell how much he removed from those chambers until you compare it to a before pic: http://www.goldnblack.net/photos/0311sqhd/IMG_2537.JPG Can't really see much done to the bowls, besides a little smoothing of the casting. Â Did he really smooth out the inner radius? Â Hard to see what he did with the valves in. Â I was hoping to get a little more for my money but rates up here are jsut outrageous. Â This guys idea of bowl work consisted of simply grinding the inner radius lip off on the exhuast side. Â Don't think I'll be going back there again. http://www.goldnblack.net/photos/0311sqhd/IMG_2532.JPG They did a decent job on the exhaust gasket match at least: http://www.goldnblack.net/photos/0311sqhd/IMG_2533.JPG http://www.goldnblack.net/photos/0311sqhd/IMG_2534.JPG Steve A. Link to comment Share on other sites More sharing options...
artinist Posted December 10, 2003 Author Report Share Posted December 10, 2003 thanks StarQuestSir for the pics, i forgot to take before pics. I am not going to smooth out the intake ports any more than what they are. the ports were matched to gasket the porter explained to me that the lower radius where the port actually starts to point down was at too high of an angle and that would be the first thing causing restrictions at high flow so that is what he tried to fix rather than try to just increase the size of the port by raising the roof. I want to end up with an 8.5 compression or close to it so I will end up boosting low 20s. I will probably order 0.1 point higher to make up for the removed material. this combustion chamber should definetly let me run several pound of extra boost without the need for higher octane compared to a stock head. Link to comment Share on other sites More sharing options...
chiplee Posted December 11, 2003 Report Share Posted December 11, 2003 this combustion chamber should definetly let me run several pound of extra boost without the need for higher octane compared to a stock head. why's that? if you have 8.5:1 you have 8.5:1. It would let you run more boost if it was the only thing you changed, but if you run higher comp pistons to make up for the lost compression you'll be right where you started. 8.5:1 static is safe for about 18psi on pump, MAX. I'm below 8:1 and feel safe at absolutely no more than 20psi with an octane booster. Effective compression in my engine at 20psi is probably around 16:1, but that's a rough guess. Link to comment Share on other sites More sharing options...
Joel Posted December 11, 2003 Report Share Posted December 11, 2003 why's that? if you have 8.5:1 you have 8.5:1. It would let you run more boost if it was the only thing you changed, but if you run higher comp pistons to make up for the lost compression you'll be right where you started. 8.5:1 static is safe for about 18psi on pump, MAX. I'm below 8:1 and feel safe at absolutely no more than 20psi with an octane booster. Effective compression in my engine at 20psi is probably around 16:1, but that's a rough guess. Compression does not directly cause detonation. Heat cases it. By removing hotspots (places in the chamber that would heat up faster than others) you remove chances for endgas auto-ignition. Chip, your safe at 25psi on pump gas! Wanna know why? You have control over your ignition system. Run less ignition advance, the motor won't need it anyway. Just have to tune the ignition back to dial in the pressure, if you so choose. There are many reasons why detonation occurs. But, to answer the questions in your mind already about why you could in fact, with the ability to control your ignition system, run higher boost safely, try to understand why ignition retarding helps keep spark knock away in the first place. The answer is time. Joel Link to comment Share on other sites More sharing options...
shift1313 Posted December 11, 2003 Report Share Posted December 11, 2003 anyways i dont have any close up pics of my head but when it came from alabama cyl head co the ports looked great, the shape was great and the machine work great. https://filebox.vt.edu/users/maperez/Starion/Jun19%2301.JPG i didnt feel the need to port it, im not sure if the caravan head had different port shapes but they were great. http://filebox.vt.edu/users/maperez/Starion/cylhead.jpg Link to comment Share on other sites More sharing options...
Metric-man Posted December 13, 2003 Report Share Posted December 13, 2003 Swirl polishing the valves helps pick up 10 CFM through the intake ports. Link to comment Share on other sites More sharing options...
artinist Posted January 8, 2004 Author Report Share Posted January 8, 2004 i was over at TEP and pick up a headgasket and also got the ARP headstuds since the price was ok $89. Saw a head sitting on the table. i asked which it was and they said it was the "street port". it was a marnel, combustion chamber was not touched and almost no work done behind the valves. vavle seat area was not hit too hard which i guess is a good thing and they tried to improve the radius. i dont know if the $75 for port matching is extra on top of the port job, in either case I don't think the amount of work matches the price. this is their pricing Street Port and Polish $280.00 Race port and polish with chamber cc (Not for street car use !!!!!!) $450.00 Match port Intake manifold to head $75.00 Link to comment Share on other sites More sharing options...
artinist Posted February 2, 2004 Author Report Share Posted February 2, 2004 ok the head was installed with the much appreciated help of kelly and melayaton. along with that we installed an adjustable timing gear(shawn) still set at factory location and i upgraded my passenger side intercooler plumbing with a wider aluminum one. i am not sure which mod to credit but there is a major power gain, suprisingly at the low end as well. lag has been reduced by at least 500rpm and the car is definetly hauling an a** and a half and brakes loose the rear tires for a second at around 4000rpm at 19psi. i would have thought most of the gain would have been over 4500rpm. it was mostly trafficy and i havent been able to open up the car on high speed and boost after a much needed oil change. i am taking the car to the track this saturday, hopefully these valve springs will hold up well to the high boost and make a good run. Link to comment Share on other sites More sharing options...
Boosted_One Posted February 3, 2004 Report Share Posted February 3, 2004 ok the head was installed with the much appreciated help of kelly and melayaton. along with that we installed an adjustable timing gear(shawn) still set at factory location and i upgraded my passenger side intercooler plumbing with a wider aluminum one. i am not sure which mod to credit but there is a major power gain, suprisingly at the low end as well. lag has been reduced by at least 500rpm and the car is definetly hauling an tail and a half and brakes loose the rear tires for a second at around 4000rpm at 19psi. i would have thought most of the gain would have been over 4500rpm. it was mostly trafficy and i havent been able to open up the car on high speed and boost after a much needed oil change. i am taking the car to the track this saturday, hopefully these valve springs will hold up well to the high boost and make a good run. That porting REALLY helps!! As you can see Art! This is why I say HOG it out...you won't lose anything on these 2.6 heads because they are WAY restrictive out of the box.... Glad to see it worked out good for ya! Link to comment Share on other sites More sharing options...
melayanton Posted March 14, 2004 Report Share Posted March 14, 2004 Â I'm below 8:1 and feel safe at absolutely no more than 20psi with an octane booster. Â Effective compression in my engine at 20psi is probably around 16:1, but that's a rough guess. youre effective compression ratio is about 18.9:1 at 20 psi with 8.0:1 static compression. Link to comment Share on other sites More sharing options...
JustPaus_88TSi Posted March 15, 2004 Report Share Posted March 15, 2004 So Art, what happened at the track on Saturday? Link to comment Share on other sites More sharing options...
artinist Posted March 15, 2004 Author Report Share Posted March 15, 2004 clutch couldnt hold crap. it did a 14.0@101 while spinning from 3rd on. stage III SPEC is going in this week. Link to comment Share on other sites More sharing options...
Joel Posted March 16, 2004 Report Share Posted March 16, 2004 I personally would not suggest to hog out any head port, no matter if the head is restrictive... thats just my opinion though. 14.0@101 isn't bad for a car that has a crappy clutch that won't hold! Joel Link to comment Share on other sites More sharing options...
vitamincj Posted March 18, 2004 Report Share Posted March 18, 2004 I personally would not suggest to hog out any head port, no matter if the head is restrictive... thats just my opinion though. Joel Come on Joel, I know you are holding back. Please explain why you don't suggest "hog"ing out a port. Too close to the water jacket? What's your reasoning? CJ Link to comment Share on other sites More sharing options...
ZeroKewl9 Posted March 19, 2004 Report Share Posted March 19, 2004 I've got a marnal and would love to bust down some times like yours but i'm sure its going to be a long road for me. Zero I wonder how much difference the porting did for your car? Link to comment Share on other sites More sharing options...
artinist Posted March 19, 2004 Author Report Share Posted March 19, 2004 i strongle recommend getting a light port job done. the area behind the valves and the sparkplug in the combustion chamber really need to be touched up and should not cost most. Link to comment Share on other sites More sharing options...
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