ViperTrippleXXX and others on my burning viper

Yamablue said:
Yes it is a stock fuel pump on an 02. I thought about puttng the corresponding XCR800 fuel pump on it, but it doesn't mix the oil in the pump. I had it set up for direct injection last year, but the shortest hose from the T got the most oil, so I nixed that an went back to original.
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Got Ya, Bender makes a kit to send the oil to the carbs if I am not mistaken.
The 02 Viper fuel pump had a hole in the bottom of the pump that would get water in it, If you had a fuel problem it could be from the pump not working at full capacity. The rpm's are killing you for sure & the squish is way tight from anything we run.
 
Here is a picture of the mag cylinder. All I can say is wow! Do I win an award or something for this piece of art? The next two are the center and the pto. Nothing going on in there. How does the wash look? Kinda rich to me.

My initally it looks like the ports are at 28.5 mm, but it is radiused a little. I'll get a better measure later when I pull it off.

Bush. I took care of the weep hole long time ago. I figured the direct oil didn't work properly cause I didn't have the check valves on the lines so the oil would load up in one manifold when it was off.
 
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I'm not really sure you would call that rich...the center isn't too rich either, actually probably a touch lean. PTO looks good. But for the mag, it is kind of hard to tell, everything looks like it got REAL hot though
 
Ive got a 02 Viper with aenn pipes and peek head like bushman said from MP.I called before ordering they told me if i ran 21cc domes I needed to run some type of race full or half n half or it would burn up. higher octain lower temps,good fuel counts.
 
Maybe I should get two of the 21cc inserts cleaned up and add the thick shim of the stock gasket to the opticool gasket. That would get my quench up over 0.050" Man my cranking cyl pressure is going to be around 105, but I know it higher when its running. Oh by the way, my cyl pressure when running at idle is about 150 lbs.
 
That porting should crank azz with CPR pipes, you gotta run it above 9000@wot. If you were running it at 8400, thats more than just a little bog. Set the clutching to run up high when crusing or it's gonna sputter with that porting.
 
what do you run for fuel with 20cc heads, is that an installed number? Sounds tight for a pump gas motor as well as the compression sounds low fro that tight a head. How high did you jack the exhaust ports? .040 on the squish sounds tight, Rather than screw around with your timing and everything else, cc the head installed and put the stock carbs on it and run it once and see if it comes home in one piece, then start going back the other way. Eliminate some of the variables. You're burning it down in the mid range I'd lose the carbs first.
 
Pump gas 92 octane for fuel. THe exhaust port are at 29.8mm. I don't know what stock is. THe guys at Mountain Perf told me I should be good to go with the 20s or 21s with my porting. Guess they were WRONG. I think I will put it back together with an extra shim in the head to get my squish above 0.050 and run the 21cc chambers.
 
reddog said:
Ive got a 02 Viper with aenn pipes and peek head like bushman said from MP.I called before ordering they told me if i ran 21cc domes I needed to run some type of race full or half n half or it would burn up. higher octain lower temps,good fuel counts.
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:o| Yup & my squish is @ 0.054
 
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put all 3 pieces in. Did the guys at MP tell you to run the 20's with only one piece of gasket? I would run it at .055 or better on a trail motor, like I said, take it out and bring it home in one piece and then go back the other way
 
I don't no about the peak heads but my comp was low with megapowers and I had them milled to get my comp up. I am running .050 squish with Bo's porting and 145 lbs comp. Seems high but very crisp running. I would think you should be able to run them heads at .050 but definitely not .040 or lower. Porting or not you are going to need decent comp and probably will not get that with higher squish than .050-.055. Easier to tune with a little higher comp also, but get them rpm's up if your keeping the cpr's.
 
Are we taking the squish measurement at the thickest part of the band (at OD of the big chamber), the middle of the squish band, or the thinnest part just next to the cylinder wall? Beacuse I know mine is thinner at the cylinder wall than towards the middle of the cylinder. I wonder if this means I have a different angle than on the stock heads.
 
Yamablue said:
Are we taking the squish measurement at the thickest part of the band (at OD of the big chamber), the middle of the squish band, or the thinnest part just next to the cylinder wall? Beacuse I know mine is thinner at the cylinder wall than towards the middle of the cylinder. I wonder if this means I have a different angle than on the stock heads.
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I have always checked @ the cylinder wall on two sides of the cylinder so the piston cant rock back & read higher than what you have. Good luck to ya & hope you say she is a rockin on monday.
 
Yeah I measured it paralell to the pin so it couldn't get affected by piston rock. What I mean it my squished solder comes out tapered so to point next to the cylinder wall is the thinnest and it gets thicker as it go toward the chamber. Is this the norm or does it mean I have the different angle on my chambers?
 
the measurement should vary about .010 to .012 between the out side and the inside. I thought this was a Viper. You're running gaskets on SRX cylinders? Lots o luck getting that to seal. You can see in the pics that it was leaking on one cylinder. And if I had to guess you have a very lean motor or too much timing.
 
These are viper cylinders. They were cut for use with orings but Bo said it sould work fine with a gasket. I debated putting orings on there along with the gasket, but it was sealed up pretty good with the full hed gasket. With just one shim it did leak. As far as the quench, if it varies, do I take the middle, the lower or the higer reading?
 
Your squish is way to tight for pump gas especially at the 14* squish band angle. On 91 octane you want to be around .055-.058" squish with the stock squish angle and stock viper timing.
 
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