Axial .28 or HPI K4.6?
03-08-2007, 11:57 PM
#51
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RE: Axial .28 or HPI K4.6?
ORIGINAL: SAVAGEJIM
Thanks so much! Im hitting their site right now as we speak! I look forwad to getting my D30M soon, Im also going to need to purchase the roto backplate as well, I never really like pull starts, especially during break-in.
Anywasy, upon further viewing of the K4.6/Axials with the D28M and D30M, there are other race tricks missing from the K4.6 and Axials. Aside from timing and port configurations, the D28/30M one way bering is a semi-cone shaped unit with scoop-like leading edges to help better atomize the fuel into the air. Th K4.6/Axial one way beaing is a plain and heavy round disc piece that lacks any of these things.
The way the ports are milled on the D28M (from what I saw of my own) are cut to direct the fuel-air charge where it needs to go where the K4.6/Axial ports are plain and perpendicular; not very useful in helping directing the fuel-air charge.
The D28M exhasust port in the engine block is nicely shaped and broad to help clear the cylinder quickly of exhaust immediately as it opens. the K4.6/Axial port has only a center "peak" in the exhaust port.
Too bad Nityrostar and Axial could not emply these ques into their engines. For the price of the STS engines, they ar packed full of very nice race features.
Thanks so much! Im hitting their site right now as we speak! I look forwad to getting my D30M soon, Im also going to need to purchase the roto backplate as well, I never really like pull starts, especially during break-in.
Anywasy, upon further viewing of the K4.6/Axials with the D28M and D30M, there are other race tricks missing from the K4.6 and Axials. Aside from timing and port configurations, the D28/30M one way bering is a semi-cone shaped unit with scoop-like leading edges to help better atomize the fuel into the air. Th K4.6/Axial one way beaing is a plain and heavy round disc piece that lacks any of these things.
The way the ports are milled on the D28M (from what I saw of my own) are cut to direct the fuel-air charge where it needs to go where the K4.6/Axial ports are plain and perpendicular; not very useful in helping directing the fuel-air charge.
The D28M exhasust port in the engine block is nicely shaped and broad to help clear the cylinder quickly of exhaust immediately as it opens. the K4.6/Axial port has only a center "peak" in the exhaust port.
Too bad Nityrostar and Axial could not emply these ques into their engines. For the price of the STS engines, they ar packed full of very nice race features.
the issues are all these race features do make the motor a little more tempermental. The Axials are truly plug and play...
The STS 30 has an excelent sleeve desgn, with nicely cut presure ports behind the transfer ports..... I also do some secret modding to the leading side of the transfer ports to also aid the shnerle effect, trapping the transfer charge between a low pressure and a high pressure to help guide it to the front of the combustion chamber.
03-09-2007, 09:34 AM
#52
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RE: Axial .28 or HPI K4.6?
ORIGINAL: supertib
the issues are all these race features do make the motor a little more tempermental. The Axials are truly plug and play...
The STS 30 has an excelent sleeve desgn, with nicely cut presure ports behind the transfer ports..... I also do some secret modding to the leading side of the transfer ports to also aid the shnerle effect, trapping the transfer charge between a low pressure and a high pressure to help guide it to the front of the combustion chamber.
the issues are all these race features do make the motor a little more tempermental. The Axials are truly plug and play...
The STS 30 has an excelent sleeve desgn, with nicely cut presure ports behind the transfer ports..... I also do some secret modding to the leading side of the transfer ports to also aid the shnerle effect, trapping the transfer charge between a low pressure and a high pressure to help guide it to the front of the combustion chamber.
For those of you who happen upon this thread and do not already know, a performance nitro engine with an agressive port timings and other race features can be harder to start and warm up as well as run since the needles need to be at a much more precise position to draw out maximum performance. Engines with a less agressive timing profile features are more forgiving as far as the needles go. Race oriented engines with port configurations like the D30M tend to breathe easier at higher RPMs. It's kind of like full sized car engines. A car with an everday cam profile is not a high RPM performer and actually suck at high RPMS. These engines are menat to operate mostly at idle and lower RPMS (for stop and go driving and moderate accelerations). A bored-oout tricked out Chevy 454ci engine with an agressive cam on the other hand will roar at its optimum operating RPM but will idle like total crap. That is why a custom hot-rod engine sitting at idle at a stop sign goes "lop-lop-lop!" It's cam profile is such that the engine is meant to run at higher RPMs and really accelerate the car (assuming very deep gears to aid in this acceleration, this is why hot-rodders get 4.11/1 or deeper rear gears). Just as in our nitro engines, a hot-rodded full sized engine can be very hard to start and warm up if tuning is not done right. That is why your shade-tree hot-rodder has to continually crank the engine over and over again as it keeps on dying on him. He needs to consider how his engine is tuned as well as if the hot-rod tricks he put on his engine will give him the output he desires but also maintains the ability to idle and not stall. It's a trade-off.
supertib,
I hope you don't mind, but can you bump up your post in which you go into the instructions of running and tuning the STS engine? This is a post that most of us fellow STS engine owners need but unfortunately it is not a sticky. Also, all new STS engine owners will definitely benefit from such an instructional post.
03-09-2007, 10:23 AM
#53
Senior Member
RE: Axial .28 or HPI K4.6?
ORIGINAL: SAVAGEJIM
This is so true,and you're right, engines using these race features (especially aggressive timing profiles) require a good selection of parts, fuel, and a good hand at tuning.
For those of you who happen upon this thread and do not already know, a performance nitro engine with an agressive port timings and other race features can be harder to start and warm up as well as run since the needles need to be at a much more precise position to draw out maximum performance. Engines with a less agressive timing profile features are more forgiving as far as the needles go. Race oriented engines with port configurations like the D30M tend to breathe easier at higher RPMs. It's kind of like full sized car engines. A car with an everday cam profile is not a high RPM performer and actually suck at high RPMS. These engines are menat to operate mostly at idle and lower RPMS (for stop and go driving and moderate accelerations). A bored-oout tricked out Chevy 454ci engine with an agressive cam on the other hand will roar at its optimum operating RPM but will idle like total crap. That is why a custom hot-rod engine sitting at idle at a stop sign goes "lop-lop-lop!" It's cam profile is such that the engine is meant to run at higher RPMs and really accelerate the car (assuming very deep gears to aid in this acceleration, this is why hot-rodders get 4.11/1 or deeper rear gears). Just as in our nitro engines, a hot-rodded full sized engine can be very hard to start and warm up if tuning is not done right. That is why your shade-tree hot-rodder has to continually crank the engine over and over again as it keeps on dying on him. He needs to consider how his engine is tuned as well as if the hot-rod tricks he put on his engine will give him the output he desires but also maintains the ability to idle and not stall. It's a trade-off.
supertib,
I hope you don't mind, but can you bump up your post in which you go into the instructions of running and tuning the STS engine? This is a post that most of us fellow STS engine owners need but unfortunately it is not a sticky. Also, all new STS engine owners will definitely benefit from such an instructional post.
ORIGINAL: supertib
the issues are all these race features do make the motor a little more tempermental. The Axials are truly plug and play...
The STS 30 has an excelent sleeve desgn, with nicely cut presure ports behind the transfer ports..... I also do some secret modding to the leading side of the transfer ports to also aid the shnerle effect, trapping the transfer charge between a low pressure and a high pressure to help guide it to the front of the combustion chamber.
the issues are all these race features do make the motor a little more tempermental. The Axials are truly plug and play...
The STS 30 has an excelent sleeve desgn, with nicely cut presure ports behind the transfer ports..... I also do some secret modding to the leading side of the transfer ports to also aid the shnerle effect, trapping the transfer charge between a low pressure and a high pressure to help guide it to the front of the combustion chamber.
For those of you who happen upon this thread and do not already know, a performance nitro engine with an agressive port timings and other race features can be harder to start and warm up as well as run since the needles need to be at a much more precise position to draw out maximum performance. Engines with a less agressive timing profile features are more forgiving as far as the needles go. Race oriented engines with port configurations like the D30M tend to breathe easier at higher RPMs. It's kind of like full sized car engines. A car with an everday cam profile is not a high RPM performer and actually suck at high RPMS. These engines are menat to operate mostly at idle and lower RPMS (for stop and go driving and moderate accelerations). A bored-oout tricked out Chevy 454ci engine with an agressive cam on the other hand will roar at its optimum operating RPM but will idle like total crap. That is why a custom hot-rod engine sitting at idle at a stop sign goes "lop-lop-lop!" It's cam profile is such that the engine is meant to run at higher RPMs and really accelerate the car (assuming very deep gears to aid in this acceleration, this is why hot-rodders get 4.11/1 or deeper rear gears). Just as in our nitro engines, a hot-rodded full sized engine can be very hard to start and warm up if tuning is not done right. That is why your shade-tree hot-rodder has to continually crank the engine over and over again as it keeps on dying on him. He needs to consider how his engine is tuned as well as if the hot-rod tricks he put on his engine will give him the output he desires but also maintains the ability to idle and not stall. It's a trade-off.
supertib,
I hope you don't mind, but can you bump up your post in which you go into the instructions of running and tuning the STS engine? This is a post that most of us fellow STS engine owners need but unfortunately it is not a sticky. Also, all new STS engine owners will definitely benefit from such an instructional post.
the STS engines aren't nearly as bad as you would think for tuning, they idle amazing, and start usualy first pull... They just need a good pipe, fuel and plug... give them those 3 things and they are almost as user freindly as an Axial, and they also hold their tune better then an Axial once they are tuned in....
But we still see guys having major issues with these mills, but its usualy due to lack of experience, and an unwilingness to take advice... They assume because their sport grade 20% worked well in a S-25 its going to work in a STS 30, and refuse to buy a good quality 30%... I have also noticed 99% of people having issues are trying to run some lower grade 20%, and as a rule the STS 30 doesn't seem very happy with 20%.... If they would just run my setup right off the bat they would have a motor that performs like the mills in my video, its that simple.... But to many people seem to think they know better LOL
03-09-2007, 12:52 PM
#54
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Thread Starter
RE: Axial .28 or HPI K4.6?
I think Axial hit the mark perfectly with their .28 engines. They are not high end engines, you can tell that by their price points and by looking at their internals, but rather they are better than the factory offered engines that come in the Savages and for some that is perfect.
The dyno sheets don't lie and I have seen some printouts (in mag reviews) where the Axial .28 wastes some other .28s and even some .32s, so all conspiracy theories and personal preferences aside, they are a great bang for the buck. Where else can you get a .28 engine that cranks out the power and torque of the Axial for $120 or less?
Lastly, I've read that the Axials are flat out awesome in lighter buggy and truggy applications. I guess everything is relative to what the engine is bolted into. I can't wait for the weather to break so I can break this thing in!
The dyno sheets don't lie and I have seen some printouts (in mag reviews) where the Axial .28 wastes some other .28s and even some .32s, so all conspiracy theories and personal preferences aside, they are a great bang for the buck. Where else can you get a .28 engine that cranks out the power and torque of the Axial for $120 or less?
Lastly, I've read that the Axials are flat out awesome in lighter buggy and truggy applications. I guess everything is relative to what the engine is bolted into. I can't wait for the weather to break so I can break this thing in!
03-09-2007, 02:40 PM
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RE: Axial .28 or HPI K4.6?
YES!!... my STS .30 and STS clutch shoes were just delivered. My STS pipe should be on it's way by now too, but I had to order it from somewhere else because they are backordered and STSmicroengines was out of stock.
So fill me in... what plugs do you suggest supertib? I've always run either O'donnell 30% race or Maxy's 30% race fuel, and I was thinking about using the Maxy's in this thing. It's 30% nitro and 10% oil, but I'm not sure of the actual oil blend that is used in it? Have you happened to try this fuel yourself?
So fill me in... what plugs do you suggest supertib? I've always run either O'donnell 30% race or Maxy's 30% race fuel, and I was thinking about using the Maxy's in this thing. It's 30% nitro and 10% oil, but I'm not sure of the actual oil blend that is used in it? Have you happened to try this fuel yourself?
03-09-2007, 03:38 PM
#56
Senior Member
RE: Axial .28 or HPI K4.6?
ORIGINAL: gravediggerracing
I think Axial hit the mark perfectly with their .28 engines. They are not high end engines, you can tell that by their price points and by looking at their internals, but rather they are better than the factory offered engines that come in the Savages and for some that is perfect.
The dyno sheets don't lie and I have seen some printouts (in mag reviews) where the Axial .28 wastes some other .28s and even some .32s, so all conspiracy theories and personal preferences aside, they are a great bang for the buck. Where else can you get a .28 engine that cranks out the power and torque of the Axial for $120 or less?
Lastly, I've read that the Axials are flat out awesome in lighter buggy and truggy applications. I guess everything is relative to what the engine is bolted into. I can't wait for the weather to break so I can break this thing in!
I think Axial hit the mark perfectly with their .28 engines. They are not high end engines, you can tell that by their price points and by looking at their internals, but rather they are better than the factory offered engines that come in the Savages and for some that is perfect.
The dyno sheets don't lie and I have seen some printouts (in mag reviews) where the Axial .28 wastes some other .28s and even some .32s, so all conspiracy theories and personal preferences aside, they are a great bang for the buck. Where else can you get a .28 engine that cranks out the power and torque of the Axial for $120 or less?
Lastly, I've read that the Axials are flat out awesome in lighter buggy and truggy applications. I guess everything is relative to what the engine is bolted into. I can't wait for the weather to break so I can break this thing in!
03-09-2007, 07:26 PM
#57
RE: Axial .28 or HPI K4.6?
Hey super/jim, im still deciding on either the Axial .28 or the STS .28. I mean ive done all the research but I want to see your opinion because of the fuel/ plugs i will be using and those are key factors. At first, I was all set on the STS cause of its excellent $115 shipped price. it has a great rep for being a very fast engine. Then I saw that with the $20 off in tower, I could get an Axial .28 for $115 plus shipping. I have also heard excellent things about this engine for being extremely easy to tune and having gobs of torque. I think im pretty good at tuning, Ive never overheated my S-25 and have to adjust it around 12 times a year (usually monthly)
I just want an overall engine that wont remind me of my old TRX 2.5 which was an absolute NIGHTMARE to tune. After every half tank it overheated and had to adjust it daily/ weekly. So im looking for a decently fast engine thats reliabe, has some parts support, and wont be a Pain In the Butt for me. I havent seen any Piston/ Sleeve combos anywhere for the STS so that worries me about parts support. The only 30% my LHS carries is Traxxas and that has way too much oil. Ill be using Byron's 20% Race formula. And the plugs are alawys Mcoy or O.S. Regualr plugs. P.S. I know with the STS you need the regualr pipe but which do you use with the Axail. Ive seen the STS pipe for $45 shipped and that I can handle but any more is off my price range. P.S. I know these engines are very powerfull, but are they complete diff shredders? Ill probably be using 17-18 Cb and the regualr spur gear that comes with the Savage 25. I cant afford to replace my diffs every 3 months, will shimming them make them that much durabe? Thanks for all the help! Tom. [8D]
I just want an overall engine that wont remind me of my old TRX 2.5 which was an absolute NIGHTMARE to tune. After every half tank it overheated and had to adjust it daily/ weekly. So im looking for a decently fast engine thats reliabe, has some parts support, and wont be a Pain In the Butt for me. I havent seen any Piston/ Sleeve combos anywhere for the STS so that worries me about parts support. The only 30% my LHS carries is Traxxas and that has way too much oil. Ill be using Byron's 20% Race formula. And the plugs are alawys Mcoy or O.S. Regualr plugs. P.S. I know with the STS you need the regualr pipe but which do you use with the Axail. Ive seen the STS pipe for $45 shipped and that I can handle but any more is off my price range. P.S. I know these engines are very powerfull, but are they complete diff shredders? Ill probably be using 17-18 Cb and the regualr spur gear that comes with the Savage 25. I cant afford to replace my diffs every 3 months, will shimming them make them that much durabe? Thanks for all the help! Tom. [8D]
03-09-2007, 08:43 PM
#58
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RE: Axial .28 or HPI K4.6?
As for the D28M, that is the one I love in my daily basher! I believe I burned upo the sleeve a gallon or two ago last fall, but the engine kept on going full bore up until I put it away for the winter. I recently took it out of winter storage and diassembled it for running again and noticed the sleeve is blued from overheating (I surpised I didnt cantch that when I cleanced it out for winter storage!). I am guessing I cooked that sleeve during the late summer or early fall last year; that was when I put in long plugs in t and my engine would over rev at idle and over heat (accoding to the temp gauge).
Anyways, upon reverting to short plugs, my engine ripped! It tuned just as easily as it did when it was brand new and just broken in.
Based on my experience, I say go STS D28M over the axial. I will hold a tune easily even with a cooked sleeve! (BTW, don't intentionally try to cook your sleeve just to see how durable your engine is. I am only telling this as my experience, I know my sleeve will not last any longer. I'm surprised it lasted more than 5 gallons of the abuse I put it through.)
Anyways, upon reverting to short plugs, my engine ripped! It tuned just as easily as it did when it was brand new and just broken in.
Based on my experience, I say go STS D28M over the axial. I will hold a tune easily even with a cooked sleeve! (BTW, don't intentionally try to cook your sleeve just to see how durable your engine is. I am only telling this as my experience, I know my sleeve will not last any longer. I'm surprised it lasted more than 5 gallons of the abuse I put it through.)
03-09-2007, 09:27 PM
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RE: Axial .28 or HPI K4.6?
ORIGINAL: rcnitrohead
...im looking for a decently fast engine thats reliabe, has some parts support, and wont be a Pain In the Butt for me. I havent seen any Piston/ Sleeve combos anywhere for the STS so that worries me about parts support...
...im looking for a decently fast engine thats reliabe, has some parts support, and wont be a Pain In the Butt for me. I havent seen any Piston/ Sleeve combos anywhere for the STS so that worries me about parts support...
My local RC store carries Axial and Axial parts, but for the price they charge, I would rather by Axial parts on-line.
03-09-2007, 10:34 PM
#60
RE: Axial .28 or HPI K4.6?
Ok so the Axials out for me now. I have to sell off $130 worth of old stuff till I can actually buy the mill. Im selling my 2 gallon S-25, and a lot of miscelaneous stuff like those Hot Bodies 7" tires (POS dont ever buy those) with 8 tanks on them. I should end up with enough money for the engine alone and I have spare for the pipe. Anyway, I will get the STS .28 as of now but...., I saw Stormerhobbies.com had an engine clearance and the XTM 457 was going for $109 and thats a complete steal. If they do get it in stock again by April, Im probably gonna go for the STS. Last question, after properly shimming your diffs, are they that much more durable then in stock form? And what other mods should I consider for the driveline? For this season, im leaving the stock dogbones until they get shredded up and then ill buy CVD's for next year unless these engines are capable of killing them sooner. Should I worry about my tranny? I have the Savage 25 with the upgraded 4 gear diffs. Thanks. Tom.[8D]
03-09-2007, 11:24 PM
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RE: Axial .28 or HPI K4.6?
If you can get an XTM 457 for $109 then forget about the Axial and STS .28s, that 6 port SH is hard to beat at that price.
Supertib or Jim--- what kind of plugs should I get for this STS .30? I'm at least a few days from even dropping it in the truck, so I have time to order whatever plug you guys recommend. I'm very impressed with it BTW. I haven't torn it apart yet, but from my little 5 minute inspection this afternoon it looks really nice. TIGHT pinch!! I'll have to preheat this one for sure.
Supertib or Jim--- what kind of plugs should I get for this STS .30? I'm at least a few days from even dropping it in the truck, so I have time to order whatever plug you guys recommend. I'm very impressed with it BTW. I haven't torn it apart yet, but from my little 5 minute inspection this afternoon it looks really nice. TIGHT pinch!! I'll have to preheat this one for sure.
03-10-2007, 02:01 AM
#62
RE: Axial .28 or HPI K4.6?
Ive heard the 457 is extremely powerfull in low end torque, I suppose the top speed shouldnt be too bad? Its probably a diff shredding monster but I think for $109, thats a steal and I hope stormer gets it back in stock! 3.8 Horses Yeah Baby!![>:]
[>:]
03-10-2007, 04:24 AM
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RE: Axial .28 or HPI K4.6?
For you Axial 28 guys...the HPI k4.6 o-ring set (part #15241) will replace all o-rings in carb and backplate.
Thought you might want to know seeing they are the exact same set for both motors just different color dust boots for carb.
Thought you might want to know seeing they are the exact same set for both motors just different color dust boots for carb.
03-10-2007, 04:36 AM
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RE: Axial .28 or HPI K4.6?
just got the part in and checked all o-rings and they are a match. I finally get to cure that air leak at the back plate!! Remember to rtv seal everything!!!
03-11-2007, 12:22 AM
#67
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RE: Axial .28 or HPI K4.6?
I called every hobby shop within a 30 mile radius of my house and they all stock Axial stuff to some degree. None of them stock anything STS or XTM. Just something to consider if you need parts RIGHT NOW, rather than waiting for the parts to come mail order.
03-11-2007, 12:25 AM
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RE: Axial .28 or HPI K4.6?
that's why I ordered a etra pullstart, owb, shims, and o-rings for my sts d30m when I purchased it...better to be prepaired than not at all
03-17-2007, 08:22 AM
#69
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RE: Axial .28 or HPI K4.6?
ORIGINAL: gravediggerracing
I called every hobby shop within a 30 mile radius of my house and they all stock Axial stuff to some degree. None of them stock anything STS or XTM. Just something to consider if you need parts RIGHT NOW, rather than waiting for the parts to come mail order.
I called every hobby shop within a 30 mile radius of my house and they all stock Axial stuff to some degree. None of them stock anything STS or XTM. Just something to consider if you need parts RIGHT NOW, rather than waiting for the parts to come mail order.
03-17-2007, 11:29 AM
#71
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RE: Axial .28 or HPI K4.6?
an SH28P6 off ebay !!! is a XTM 457 or LRP Spec 2..... these are the motors guys should be buying over the Axials any day.... More power everywhere, and way more RPM...
03-17-2007, 04:49 PM
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RE: Axial .28 or HPI K4.6?
HEY GUYS!!!!!!!!!!!
what about the carbs? will the needles on the axial fit the 4.6 carb?.....cause my MSN fell off the carb somehow today and now i can't start the truck!!!!
what about the carbs? will the needles on the axial fit the 4.6 carb?.....cause my MSN fell off the carb somehow today and now i can't start the truck!!!!
03-17-2007, 04:51 PM
#73
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RE: Axial .28 or HPI K4.6?
ORIGINAL: ravenlunatic
HEY GUYS!!!!!!!!!!!
what about the carbs? will the needles on the axial fit the 4.6 carb?.....cause my MSN fell off the carb somehow today and now i can't start the truck!!!!
HEY GUYS!!!!!!!!!!!
what about the carbs? will the needles on the axial fit the 4.6 carb?.....cause my MSN fell off the carb somehow today and now i can't start the truck!!!!
