Restoring The Hpi 25 P&p Artical

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hpi_25_port_003.jpg
 
sorry for poor quality, you can print pages from the gallery if you can not view here.
I'm working on a commodor 64 computer.
 
Only us old guys even know what a comodore is. damn your old.
stay on topic chunkys watching. lol hi chunky.
 
has anyone messed around with crank porting. Ive tried on a couple of engines. first was the ns.21 i lightened the crank and added another flute then bored the inside and polised itwith my dremel. then i put more ports int he sleeve (4). when i stared it and ran it the power was incredible i think it would keep up with my axial 32 or my sts30. it only lasted about a half a tank then the wristpin broke! if i can talk blazer into it i'll give it to him to post pics. I also found out that the .21 only runs on one bushing in the bottom of the rod which isnt good for the increades rpms.
 
The differents between the F4.1 and the .25 is, that the F4.1 has more ports, and a better flow (also more power).
This article is written for the .25 block of the savage 25.
But if you unterstand the flow of the fuel and air mixture and the meaning behind the P&P tuning, you can do every engine.....

BUT BE CAREFUL !!!!
 
I can tell you from personal experience to research this topic exstensively before attempting to do it yourself. I'm not going to link other forums but there is a guy out there that has many engines with pics of the mods he has done to them. He's done almost every block you can think of and that's what I went by and my results are still questionable.
 
Hey I have read a lot of articles on this saw a lot of photos like six months straight, I totally understand the timing sequences and the differance in bore size and timing of the carb in let. I even have a good motor (extra) to work on. But totally think you can over do this one If and when I do this I'm going small. Like just open the exhaust and polish the air flow vents ( ports) and run it. I so think this would add a noticable improvment.

Yeah I know I haven't done it yet but I still think thats the way to do it.
 
I'll bet that Cre is right on this one...
He was really in to the process of finding the right info on these mods.

One thing for sure, you won't be disapointed if you perform the mods correctly.
 
Does anyone have a copy of the pdf they would like to share?

I don't see it anywhere, am I missing something?
 
& I am very sorry it took years for me to put this up here but its 3 pages you should copy, paste and print it out!
 
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