The chain appeared a little dry so we thoroughly lubed it an re-ran the test:
The engine spec were unchanged and shows the importance of keeping the chain lubed.
Blue line is Paul Turner pipe and silencer
Red is Dr Q / Shearer and silencer
Green is Dyno Port pipe and silencer
We pulled the cylinder a few times, modified the ports to the current level testing each increment of port changes. We installed and tested the HPR/V2 reed assembly and also installed a TM 38 Mikuni bored to 41.5mm.
After getting the ports in the ballpark for this stage of testing, we stated our LT 250 pipe development process. We are showing the graph of what we are calling HPR Test Pipe # 1. The pipe has more Peak power than the other pipes but it is not acceptable to us because we believe we can develop the pipe and ports to produce a wider power band with as much or more peak power and still make it produce more power in the mid and lower RPM range.
It takes time to develop a pipe and port package. Stay tuned for updates:
Blue line is DR Q / Shearer pipe and silencer
Red line is HPR test pipe # 1 pipe and silencer
Green line is Paul Turner pipe and silencer
I'll ask.....will you be making a lt250 pipe available any time soon?
Wish you had one of those FTZ pipes to test., Jerry we also posted these results on SQ-HQ Face Book Site.
get a power valved engine. the 88-92 powervalve puts the T in torque. and its the same size as an lt500. you cant sell that pipe to me based on the 87/ no way! im better off taking joe blows advice on pipes. or am i wrong?
well done trying to fix the scp top end but its been done allready. Also the pt pipe will slay on the track! your just making a rev pipe for a torque port on a non powervalved engine. makes NO sense whatsoever!
get a power valved engine. the 98-92 powervalve puts the T in torque. and its the same size as an lt500. you cant sell that pipe to me based on the 87/ no way! im better off taking joe blows advice on pipes. or am i wrong?
well done trying to fix the scp top end but its been done allready. the pt pipe will slay on the track! your just making a rev pipe for a torque port on a non powervalved engine. makes little sense to me.
The 87 engine is a powervalved engine. 85-86 are the non-pv ones
I ve seen similar results with the testing i have done. Now thats there's some actual data to compare, ill post up a couple graphs from the last time i had a 250 on the rollers. All dyno testing was done with a 92 small reed engine , 41.5 tm mikuni, v force 2 reeds on Heminutt's cylinder.
Red line is Ftz pipe
Blue line is Shearer/Q
Same engine same day, I should add all runs were on a Dynojet eddy current 188 machine. we spent about 10 hours on the machine that day. Each pipe was run through all the same variations, power valve changes jetting changes etc untill we had optimised each pipe. Pipes were all run from 3/4 - 2 turns on powervalve.
Red is Dynoport
Blue is Ftz
get a power valved engine. the 88-92 powervalve puts the T in torque. and its the same size as an lt500. you cant sell that pipe to me based on the 87/ no way! im better off taking joe blows advice on pipes. or am i wrong?
well done trying to fix the scp top end but its been done allready. Also the pt pipe will slay on the track! your just making a rev pipe for a torque port on a non powervalved engine. makes NO sense whatsoever!
I am not trying to sell you a pipe. I am ashamed of test pipe #1 and it's narrow power band. I was trying to show the members the effects different pipes have on the power curve on the same engine. If I can build a pipe that comes on similar to the Paul Turner and has the top end similar to test pipe # 1, I will make pipes. In the mean time I will keep testing a showing the results from time to time
get a power valved engine. the 88-92 powervalve puts the T in torque. and its the same size as an lt500. you cant sell that pipe to me based on the 87/ no way! im better off taking joe blows advice on pipes. or am i wrong?
well done trying to fix the scp top end but its been done allready. Also the pt pipe will slay on the track! your just making a rev pipe for a torque port on a non powervalved engine. makes NO sense whatsoever!
You are so out of text, its just pipe testing comparing, I went through six versions of this with my own pipe , I bet HPR will be at #4 to #5 before he see results that he is happy with, we have been asking for dyno post of the LT250s for years, and we got them, the correct answer should be Thank You Jerry, looking forward to seeing new revisions and postings instead of posting trash that you don't understand. I have a very low tolerance for this kind of posting, keep it positive please.
Jerry and Carl. Which style Dyno Port was done in your dyno testing? They have a Mid-Top and a "BIG Volume" listed.
I like seeing that ftZ and shearer dyno comparison. That ftZ has a nice power curve.
Jerry and Carl. Which style Dyno Port was done in your dyno testing? They have a Mid-Top and a "BIG Volume" listed.
The Dyno Port pipe we tested had a mid-section circumference of 380 mm and 140 mm long
The one's I tested with were the big volume pipes. Its belly section is also 380 c and 140 long.
Any pics of the dynoport big volume vs mid top? How is the silencer quality?
Looks like a good baseline pipe to work off of jerry like u said bring that power on a little sooner you will have a little monster. Always amuses me when some1 that doesnt have the knowledge to make a legit comment but trys to anyways..
88-92 powervalved engines are superior on the track. the powervalve is the same size as a lt500 aswell as the reeds.
a plus 2mm piston will slightly increase case compression. as would moving the reed closer to the piston.....
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i like the dyno that ice racer posted. there clearly is no " best exhaust" »» THEY ALL MAKE THE SAME TORQUE» the paul turner is great for 6000 rpm. the dyno port is great for 7000 rpm. the ftz is great for 8000 rpm. everything else is just ok.....
I need to measure up my Dynoport and see what one it is. Im gonna give it a whirl this summer on the 285 and see how she runs. Its the only pipe I have rode around on, except for the HPR #1.
88-92 powervalved engines are superior on the track. the powervalve is the same size as a lt500 aswell as the reeds.
a plus 2mm piston will slightly increase case compression. as would moving the reed closer to the piston.....
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i like the dyno that ice racer posted. there clearly is no " best exhaust" »» THEY ALL MAKE THE SAME TORQUE» the paul turner is great for 6000 rpm. the dyno port is great for 7000 rpm. the ftz is great for 8000 rpm. everything else is just ok.....
you do know that the 87 motors are power valved... right?
Figured a smart guy like yourself would know that.
There is a dynoport for sale on Craigslist in illinois
