Ring gaps 4.6 v8 1 bar of boost

General Chat And Help Regarding Turbocharging and Supercharging.

Moderator: phpBB2 - Administrators

Post Reply
Tony22593
Newbie
Newbie
Posts: 29
Joined: Sat Sep 03, 2016 2:12 pm

Ring gaps 4.6 v8 1 bar of boost

Post by Tony22593 » Mon Jul 16, 2018 1:58 pm

Hi guys,
I'm struggling with this part of the engine build as it seems there is definitive answer. I have a standard bore with Goetze rings. What gap would you recommend? We are aiming for around 400hp

Thanks in advance.
Tony


Land Rover discovery 2 top hat 4.6 v8 4.0 pistons stage one heads Kent h200 cam Range Rover maf Mark Adams remap in lpg

Tony22593
Newbie
Newbie
Posts: 29
Joined: Sat Sep 03, 2016 2:12 pm

Re: Ring gaps 4.6 v8 1 bar of boost

Post by Tony22593 » Mon Jul 16, 2018 7:05 pm

The strange thing is I have put the top ring in the bore and the gap was 0.55mm which is nearly 22 thou which is already quite large when referenced to the manual. The upper limit in the manual is 20 thou. I want it to be safe but at the same time not go through more oil than fuel!
Land Rover discovery 2 top hat 4.6 v8 4.0 pistons stage one heads Kent h200 cam Range Rover maf Mark Adams remap in lpg

User avatar
Blown v8
Gold Member
Gold Member
Posts: 334
Joined: Sun May 25, 2008 2:20 pm
Location: Kent

Re: Ring gaps 4.6 v8 1 bar of boost

Post by Blown v8 » Tue Jul 17, 2018 5:29 pm

IMG_3841.PNG
Hope this helps

Tony22593
Newbie
Newbie
Posts: 29
Joined: Sat Sep 03, 2016 2:12 pm

Re: Ring gaps 4.6 v8 1 bar of boost

Post by Tony22593 » Tue Jul 17, 2018 7:07 pm

Thanks for that. Have gone with 0.025" top ring and 0.032" second ring as reccomended by Allan (rossco). It was a bit strange that the gaps were so big in the first place I wasn't sure whether to leave them be or not. Maybe the material is slightly more expansive when hot.
Land Rover discovery 2 top hat 4.6 v8 4.0 pistons stage one heads Kent h200 cam Range Rover maf Mark Adams remap in lpg

User avatar
stevieturbo
Forum Contributor
Forum Contributor
Posts: 3498
Joined: Sat Nov 18, 2006 6:22 pm
Location: Northern Ireland

Re: Ring gaps 4.6 v8 1 bar of boost

Post by stevieturbo » Tue Jul 24, 2018 10:13 am

Never ever too small.

And no...ring gaps have nothing whatsoever to do with oil use...unless the gap was like 10mm or something silly.

Bore finish is all vital when it comes to oil use. Not ring gap.

There are no downsides at all to a few thou over and safe.

As to top, 2nd gap relationships etc...it will depend on rings used and their design. It isnt generic as some rings rely on some pressure behind them to assist sealing ( pretty much all top rings do ), whereas others will not want pressure hence often the larger 2nd gap.
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

Tony22593
Newbie
Newbie
Posts: 29
Joined: Sat Sep 03, 2016 2:12 pm

Re: Ring gaps 4.6 v8 1 bar of boost

Post by Tony22593 » Tue Jul 31, 2018 3:15 pm

Thanks mate. Was a bit concerned. All built now and waiting for a day off to come so I can fit it!
Land Rover discovery 2 top hat 4.6 v8 4.0 pistons stage one heads Kent h200 cam Range Rover maf Mark Adams remap in lpg

Post Reply

Return to “Forced Induction”