77898e-k
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77898e-k i bought the 77898e-k kit and after reading i measured the epc spool on the original, and found that the original was a .421, can i still install the .490 without damaging the tranny? or do i need to get the 77898E-4K?
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I do understand that there is a length diff. between the pre iss and post iss why i am confused is this statement from sonnax
1.907" Long Sleeve.421"Valve:
Sonnax 77898E-4K may be used, but noticeably firmer shifts will occur.
No Sonnax ratio available.
the reference where is says from a .421 a Sonnax 77898E-4K may be used, but noticeably firmer shifts will occur. which is a .470 sized piston,
I purchased the 77898E-K which is a .490, by mistake, and I'm just wondering if it will cause problems down the road, Transgo sells a boost kit also, and they say it's a .500 piston with no exceptions but early and late models, personally i don't think it will hurt, but while the tranny is still tore down i just wanted to ask the question, doing a google search doesn't really answer my question,
Thanks for your input
1.907" Long Sleeve.421"Valve:
Sonnax 77898E-4K may be used, but noticeably firmer shifts will occur.
No Sonnax ratio available.
the reference where is says from a .421 a Sonnax 77898E-4K may be used, but noticeably firmer shifts will occur. which is a .470 sized piston,
I purchased the 77898E-K which is a .490, by mistake, and I'm just wondering if it will cause problems down the road, Transgo sells a boost kit also, and they say it's a .500 piston with no exceptions but early and late models, personally i don't think it will hurt, but while the tranny is still tore down i just wanted to ask the question, doing a google search doesn't really answer my question,
Thanks for your input
Last edited by kyle west; Oct 29, 2017 at 09:59 AM. Reason: corrected
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.421" is a V6 boost valve size, Not recommended for V8 engines.
.470" is the stock V8 boost valve size.
.490" is a exclusive Sonnax performance boost valve.
The .490" is a nice upgrade behind all V8 engines, The only shift that will be noticeably affected is the 1-2....But with a small 553 2nd piston it probably won't be that bad.
.470" is the stock V8 boost valve size.
.490" is a exclusive Sonnax performance boost valve.
The .490" is a nice upgrade behind all V8 engines, The only shift that will be noticeably affected is the 1-2....But with a small 553 2nd piston it probably won't be that bad.
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Verdad Gallardo TECH Fanatic
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The 4L60E-LB1 & 4L60E-LB2 are kits that include a PR spring, The OP is looking at Boost Valves that do not come with a PR spring.
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From: Fort Worth, Texas
Joined: Mar 2007
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From: Saskatchewan, Canada - where arguing "DA" is for the slow and weak...
Oversized Boost Valve &
Spacer (.490") Factory Style
Patent No. 6,619,323
Spacer (.490") Factory Style
Patent No. 6,619,323
https://static.summitracing.com/glob...-4l60e-lb1.pdf
http://kaztranz.com/uploads/Sonnax_Binder.pdf