ring end gap venoilas

[mo' parts]

i know there was a similar thread, but couldnt find it. if someone could point me in the right direction, or have suggestions, it is much appreciated.

i thought i read some where about running tighter ring gap on the top or second ring....am i in left field?? or stick to the specs.

and the thread i couldnt find was about .020 over venoilas w/ .75 mm rings..
anyone.. they are file fit sealed power so it wouldnt really matter right????

would like to assemble motor by mid week(next week). to go to mopar nats. in marion on the 4th weekend. picking it up from shop tommorow. :thumbs up have everything but clutch.......

thanks in advance! :big grin:

[bigness319]

If you have ordered venolia pistons from FWD performance you'll want to use the next size up rings and file them down because Sealed power doesn't make a file fit ring for our cars. The spec sheet that came with my venolia's says use .003-004 per inch diameter gap, which means set the gaps at around .010-.020 thou. The Mopar performance "Bible" recommends no more than .040 end gap.

[Turbofreak]

top ring should have .015-.018 gap if using high boost (18+psi), second ring should have .016-.020 gap....

leave the oil expander rings alone as long as they have around .030 to .050 gap in them....


When filing the rings.... make sure and file down only, do not pull up on the ring....

file carefully and slowly, and make sure and remove any edge burrs before re-fitting the ring in the bore so as not to scratch the bore....

when you are satisfied with the gap, use a fine stone to polish the ring butt ends where you filed...

I cannot recommend buying the next step up or down and file fitting them to the bore...

buy the proper size ring set for your bore size and gap them accordingly... usually they are a little tight (.010) anyways... but check to be sure....

otherwise a different size will not seal well because it is not concentric to the bore (slightly out of round...)

GOOD LUCK!!!
RYNO
OMNILET

[bigness319]

I forgot to mention that the venolia's I ordered are sized slightly larger than a normal piston, and that they require more clearance than a normal cast piston (.003 vs. .007), so the ring gap may be excessive if you don't use a oversize/file-fit rings.

[Turbofreak]

Bore the hole on the block to match your venolia pistons.... each hole may be different by .001 or so to match your pistons....

BTW- I learned this the hard way....

Venolias need .006-.007 minimum clearance... the more power/heat you plan on making, the more clearance you better use....up to about .010 clearance, but your ring life/seal will suffer because of the piston rocking around in the bore so much...

they will rattle when the engine is cold, but don't worry, it will go away when it gets warmed up....

LUCK!!!
RYNO
OMNILET

[glhsken]

One of the main reasons I went WISCO. They only spec a .0035" clearance for their pistons. They have a lot of Force inducted experience.

Ryan, I run my gaps slightly larger. Reeves did this on his car and has had excellent results. His are much larger than what I went with but mine are .020 and .022.

[Turbofreak]

thanks Ken!!

I am going to custom made total seal rings this time.. already have them... so gapping is kinda a thing of the past for me hopefully...

Better to be too much gap than not enough!!!

RYNO

[glhsken]

Quote:

Originally Posted by Turbofreak Better to be too much gap than not enough!!! RYNO

Especially at boost over 20 psi with larger turbo's and I/c's :thumbs up

We've seen no appreciable increase in oil usage with the larger gaps. Our fear was it would add some built in "Blowby". A little smoke on start-up that quickly goes away when the piston heats up.

[mo' parts]

i ordered the pistons, pins, locks and rings from FWD. .020 pistons and i was sent a set of .75mm sealed power rings. the shop bored and honed the block to fit using the specs given w/ the pistons. picking it up at 5:00(today):thumbs up

so the gap should be????? will be running 15-18 on street and 22-25 on the track. .020 on the top and .022 on the second?

want it done right the first time.

thanks guys.

[mo' parts]

Quote:

Originally Posted by glhsken One of the main reasons I went WISCO. They only spec a .0035" clearance for their pistons. They have a lot of Force inducted experience. Ryan, I run my gaps slightly larger. Reeves did this on his car and has had excellent results. His are much larger than what I went with but mine are .020 and .022.

ill be doing wiseco from now on. i just couldnt wait the 3-4 weeks this time around. i have another t2 block, may use it for wiseco and 16 valves!!(hopefully)

we need to get on wiseco to carry them in stock(usual sizes). i always ran them in the dirt bikes and atv and abused the h@#! out of them!!! love them.

[glhsken]

I run .020/.022", my buddy runs .026/.028" (yes, really that big) Most shops want to install roughly .014/.016". We run the bigger gaps because we live above 20 psi and butting ring ends pops the top right off the piston

[glhsken]

I've asked duane to carry them, maybe I'll get in touch with him again.

[mo' parts]

good i couldnt ever get ahold of him. ill be looking for some in a couple months. the gap your running according to my repair manual is in the middle of the standard and service limit. but you know i got the boostin bug. so i dont want the tops to pop off!!! i had the shop freshen the motor for me, rod resizing, polish the crank and slightly open up the oiling hole on the rods like cindy recommended. my dad and i are going to assemble it. hes done more motors than i have. but ive done a couple. i would rather KNOW whats going on inside by doing it myself. :big grin:

[mo' parts]

should i file vertically? like mentioned earlier, or horizontally?

[mo' parts]

its together!!!!!(shortblock)
waiting to get clutch.
turns out .75 mm is .029 so very little filing after .007 piston clearance. :thumbs up