Do Triple Pipes With Thinned Head Gasket?

supercharged111

supercharged111

Member
Joined
Sep 12, 2011
Messages
114
Age
42
Location
Da U.P.
I have a set of SLP triple pipes about to go on, wondering if a thinned head gasket pairs any worse with them vs a stock single pipe? On the tech page it mentions not going with a single layer for triple pipes, rather the 2 thin layers. When you stop and think about it, there will be more air being crammed into the cylinders without the ignition timing being changed to account for that. I guess the only way to know for sure is to read the plugs? When the trails are straight and smooth the throttle tends to get parked on the bar, so that's what I need to tune for.
 
Going from a triple head gasket to a single layer is like shaving the head .020".
A reduction of .020" clearance brings the squish band clearance down to @ .055" and increases static cranking pressure by @ 20lbs and obviously increases the compression ratio of the engine.
For extended WFO riding a higher compression ratio requires very good fuel and fussy jetting.
Reducing the squish by .020" works good when the engine is also ported and running triple pipes.
Unless you are going to also port the engine I would stick with a two layer gasket and premium + fuel and conservative jetting as the hp difference would be minimal anyway.
 
When you port the engine the exhaust port is normally raised a few mm. By raising the exhaust port you decrease the corrected compression ratio...squeeze from closed exhaust port.
 
I run 91 octane with triple pipes. I layer head gasket. Between my buddies and I, we have around 5 sleds with that setup.
Never had problems yet.
 
Not sure if I should be nervous? I've run it that way single pipe for may years. Was just wondering if triple pipes in and of themselves changed the pre-ignition tolerance. Sounds like porting changes the dynamic compression ratio so yeah, definite increase in knock margin there.
 
One of the good things about the SLP pipes is they don't have very restrictive stingers/silencer so they are more forgiving then some pipes that were available for the Red Head triples.
I have many 1000s of miles on Bender piped red head triples, between my son's and my previous sleds, and they work great but ours were ported and we never held them WFO for extended lengths of times.
One of my all time favorite sled combos.
 
I did chicken out and do 2 layers on the gasket. Got some miles on the new motor and so far so good. I'm hoping to get rolling on the triple pipes next week, just waiting on 1 more rivet and 2 more weights.
 
You must log in or register to reply here.


Back
Top