GO-435 Pistons in O-435

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krazymatt
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GO-435 Pistons in O-435

Postby krazymatt » Sun Nov 22, 2015 8:29 pm

Would I gain anything by putting the Pistons from angle valve GO-435 into the str8 valve cylinders on o435. They say they are 7.3:1 in the angle valve cylinders. The o290d2 pistons for str8 valve say they are 7.5:1

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kmr0290
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Re: GO-435 Pistons in O-435

Postby kmr0290 » Mon Nov 23, 2015 6:52 am

The 7:5 to 1 are the better Pistons. But a whole lot of work,time, money for an at best 5hp gain. If your planning on re-ringing it anyway go for it. But the last ones I bought were 125$ a piece. Plus rings. Ouch
5x12 ibuiltit 0290 swinging 66" whirlwind ss, 0320 coming soon

krazymatt
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Re: GO-435 Pistons in O-435

Postby krazymatt » Mon Nov 23, 2015 9:46 am

Was just curious if the go435 pistons would make more compression in the str8 valve cylinders than the o290d2/7.5:1. I know you can run the angle valve Pistons on the str8 valve cylinders on the 540s and it bumps the compression up some. Just didn't know if was same for these motors and or if they would clear, the go435 Pistons are popup with valve reliefs cut in them and the 290d2 ones are flat... The ring set is same for both from my understanding. Pistons arnt much that different in price.

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kmr0290
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Re: GO-435 Pistons in O-435

Postby kmr0290 » Tue Nov 24, 2015 7:01 am

It's the angle valve cyl that makes the difference. The compression ratio will stay the same in either cyl. If they r 7.5:1 in the str8 valve theyll be the same in the AV. Still the same bore n stroke. Call Gary barber I think they did make a better piston for the 435. I think it was 7.8:1 not sure. If you take the 7.5:1 and put the 7.3:1 in there. U will loose hp.
5x12 ibuiltit 0290 swinging 66" whirlwind ss, 0320 coming soon

krazymatt
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Re: GO-435 Pistons in O-435

Postby krazymatt » Thu Dec 17, 2015 7:30 pm

kmr0290 wrote:The 7:5 to 1 are the better Pistons. But a whole lot of work,time, money for an at best 5hp gain. If your planning on re-ringing it anyway go for it. But the last ones I bought were 125$ a piece. Plus rings. Ouch

The price on rings for these went up again 12/12/15. Rings for steel cylinders were 95 a hole and rings for chrome cylinders were just over 200 a hole!!!

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Re: GO-435 Pistons in O-435

Postby Larry » Fri Dec 18, 2015 12:13 am

How do you figure angle valve and straight valve pistons will be the same compression if you interchange then? They have totally different combustion chambers between the two.

krazymatt
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Re: GO-435 Pistons in O-435

Postby krazymatt » Sat Dec 19, 2015 7:00 pm

Larry wrote:How do you figure angle valve and straight valve pistons will be the same compression if you interchange then? They have totally different combustion chambers between the two.


I was wondering the same, I would guess the 7.3:1 angle valve Pistons would make higher compression than the 7.5:1 when used in the straight valve cylinders... Just curious how much more and if there would be Clearence issues.

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Re: GO-435 Pistons in O-435

Postby goldhunter_2 » Sat Dec 19, 2015 9:50 pm

if you want higher compression just deck your case
.


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krazymatt
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Re: GO-435 Pistons in O-435

Postby krazymatt » Thu Dec 24, 2015 9:27 am

goldhunter_2 wrote:if you want higher compression just deck your case


Trying to avoid taking the motor down that far. Just wanting to freshen up the top end. Gonna re ring it already have new rings for 4 of the jugs and have 3 brand new 7.5:1 Pistons. So was trying to figure out to buy 3 more of the 7.5:1 Pistons or try to find 6 of the angle valve ones. Rings are the same. Think I am just gonna go forward with the 7.5:1. Anyone know where I can get 3 more of them? 69841

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Re: GO-435 Pistons in O-435

Postby avtomike » Tue Jun 13, 2017 2:46 am

kmr0290 wrote:It's the angle valve cyl that makes the difference. The compression ratio will stay the same in either cyl. If they r 7.5:1 in the str8 valve theyll be the same in the AV. Still the same bore n stroke. Call Gary barber I think they did make a better piston for the 435. I think it was 7.8:1 not sure. If you take the 7.5:1 and put the 7.3:1 in there. U will loose hp.

kmr0290, can you tell me phone number of Gary Barber? I have a 6 chrome plating cylinders, but no one std piston for my o-435.

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Re: GO-435 Pistons in O-435

Postby avtomike » Tue Jun 13, 2017 2:54 am

krazymatt wrote:
goldhunter_2 wrote:if you want higher compression just deck your case


Trying to avoid taking the motor down that far. Just wanting to freshen up the top end. Gonna re ring it already have new rings for 4 of the jugs and have 3 brand new 7.5:1 Pistons. So was trying to figure out to buy 3 more of the 7.5:1 Pistons or try to find 6 of the angle valve ones. Rings are the same. Think I am just gonna go forward with the 7.5:1. Anyone know where I can get 3 more of them? 69841


krazymatt, What piston did you install in the end?
Do you have the installation experience of the angle valve pistons?

krazymatt
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Re: GO-435 Pistons in O-435

Postby krazymatt » Wed Jun 14, 2017 6:02 am

I got the 7.5:1 pistons from jt540. They are out of o-290d2, part # 69841. Was happy with them. Justin has a lot of parts for the 435s.


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