Any one out there ever tried this combo 1976 ported cylinders on a 1980 Srx my question is.I need to know what heads work best with these cylinders I'm using stock pipes 38 mm round slid carbs comet 102c clutch I have 18 /33 gearing.I'm building this sled for 300 ft. Drags any info would be great I need this thing to fly thanks. 
You need AAEN or DRP pipes and BIGGER carbs if you want to fly. Head.. depends of fuel you will use. You can deck and reshape 8G9 heads if need more CR.
YAMMIEGOD3:16
Active member
I DID IT TO MINE SIMILAR, BUT MINE WAS A 78 SRX. PORTED 78 CYLS TO 76 SRX SPEC, 76 SRX 440 PIPES, 8G9 HEADS, .40 mm CARBS, 102 C , 17/31 GEARING. 3:16 (YAMMIE TONY)
Ok so how far can I shave the heads without messing up the squish. Wat would be recomended tried and true.
What kind of clutch setup did u guys use and were did u have ur secondary set at.for fuel Gona run 110 octane.
YAMMIEGOD3:16
Active member
YOU CAN CUT ALOT IF YOUR GONNA RUN 110. BUT DON,T RUN ANYTHING ELSE. SQUISH STOCK I BELIEVE WAS AROUND .58 THOUSANDS. I GET DOWN TO AROUND .35. WHAT PIPES YOU USEING HERE. 3:16 (yammie tony)
N-1 weights with blue spring
Not sure about pipes I'm thinking aaen pipes
Ok thanks alot guys this will help out
YAMMIEGOD3:16
Active member
AAEN RACE PIPES RUN AT 9700/ 10,000. N-1 WEIGHTS WORK GOOD, BUT WILL NEED TO BE PRETTY LITE. ALSO YOU WILL NEED AT-LEAST 6000 ENGAGEMENT. HARD TO RECOMEND COMET STUFF NOW, HEARD THAT STUFF IS GETTING HARD TO FIND. 3:16 (yammie tony)
I believe comet is back in bussiness Dennis Kirk has all the parts in stock. I order some comet parts from them last week.
What hp. U think I can make with what u guys have told me.
YAMMIEGOD3:16
Active member
HIGH NINETIES. and glad comets back around 3:16 (yammie tony)
WopOnTour
Member
What pistons do you guys run/recommend when using the ported 77 cylinders?
Are there any decent pistons that have 20mm pins (using 78 bottom end) that will work?
Thanks
WOT
Are there any decent pistons that have 20mm pins (using 78 bottom end) that will work?
Thanks
WOT
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YAMMIEGOD3:16
Active member
WILL WORK WITH ANY LOWER END. AND YAMAHA PISTONS IF YOU CAN FIND THEM. i think the 78-79- 80 pistons can still be had. 3:16 (yammie tony)
I'm not an expert just wat I have read listen to yammi god he knows what he's talking abouty201srx said:
YAMMIEGOD3:16
Active member
NOPE, 76/ 77 SRX HAD 18 mm. 3:16 (yammie tony)
YAMMIEGOD3:16
Active member
TRY AND HELP YOU GUYS SOME HERE.
1976 SRX USED ITS OWN RING WHICH WAS CLOSER TO THE 433 GPX. 77 SRX RING WAS DIFFERENT. FIRST YEAR OF DOWNWARD SLOPE TO HELP SEAL COMPRESSION BETTER. PISTONS WERE THE SAME, BOTH WERE 18 mm WRIST PIN.
1978-79- 80 SRX ALL USED SAME PISTON, RING (downward slope), AND WERE 20 mm WRIST PIN. SOME YAMAHA FOLKLORE SAYS THE 78 SRX HAD DUAL RINGS. I DID SEE ONE. I ALSO HAD A 78 SRX FROM LIKE NEW THAT DID NOT. WITTH ALL THIS SAID, IF YOUR USEING A 77 LOWER END, 78-79-80 PISTONS WON,T WORK. AND VISA/ VERSA. 3:16 (YAMMIE TONY)
1976 SRX USED ITS OWN RING WHICH WAS CLOSER TO THE 433 GPX. 77 SRX RING WAS DIFFERENT. FIRST YEAR OF DOWNWARD SLOPE TO HELP SEAL COMPRESSION BETTER. PISTONS WERE THE SAME, BOTH WERE 18 mm WRIST PIN.
1978-79- 80 SRX ALL USED SAME PISTON, RING (downward slope), AND WERE 20 mm WRIST PIN. SOME YAMAHA FOLKLORE SAYS THE 78 SRX HAD DUAL RINGS. I DID SEE ONE. I ALSO HAD A 78 SRX FROM LIKE NEW THAT DID NOT. WITTH ALL THIS SAID, IF YOUR USEING A 77 LOWER END, 78-79-80 PISTONS WON,T WORK. AND VISA/ VERSA. 3:16 (YAMMIE TONY)
WopOnTour
Member
No, 76-77 had the smaller 18mm wrist piny201srx said:
But as I said I have a 78 bottom-end and equipped with the 20mm rod. (smaller studs though- weird)
But the cyls & heads are 77
What I'm looking at is 20mm piston options available.
Can anyone recommend the Wiseco 2282 here?
Thanks for any help for best choices, results, sources, etc
WOT
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