I've been searching, but I can't find any detailed information on welding up the quench pads for a forced induction application.

I'm mostly worried about longetivity of the welds. An old friend of mine was worried that the welds could break loose if the engine is pushed too hard..?

For those of you who got welded combustion chambers, how long have you had it? What kind of turbo setup are you running? Is your car daily driven, autocross, road race, etc?

Thanks for any input!

 

UP

 

Hmm... Nobody?

 

Well first off if they are worried the weld will fall off then it's not welded it must be glued on there.Second no it won't hurt you any it will just raise the compression in relation to stock.

 

The purpose isn't so much as to raise the compression ratio, but rather to resist detonation. Higher quench = more efficient burn. For example, the B18B quench pads are relatively non-existant when compared to the D16Y8 or B18C1 (GSR) design.

By doing this I would primarily hope to increase engine longetivity, among other things...

 

In most cases it's not worth the effort.To be done right the seats have to be replaced also and that gets expensive.The little gain your looking for can be achieved other ways,such as a piston w/raised pads that matches the chamber.

 

Hmm... Makes sense. I guess it all comes down to cost then. Thanks for your input!

 

I've heard of phenominal gains in detonation resistance from reshaping combustion chambers to promote faster burn characteristics. I talked to a guy who does this for people and on his AE86 street car, he said was he was running 14.9:1 compression on 87 octane on a built NA motor revving to 10k with no signs of detonation.




Modified by LeGeND4LiFe at 4:50 AM 3/10/2006

 

maybe it could help prevent detonation, but when doing this, you MUST def. 100% knowing of what you are doing... otherwise its more worse then it help.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LeGeND4LiFe &raquo;</TD></TR><TR><TD CLASS="quote"> on his AE86 street car, he said was he was running 14.9:1 compression on 87 octane on a built NA motor revving to 10k with no signs of detonation.
Modified by LeGeND4LiFe at 4:50 AM 3/10/2006</TD></TR></TABLE>I might want to raise the BS flag on this one

Most people don't realize that the S2000 piston actually goes inside the cylinder head to acomplish quench. The better burning allows it to pass smog easier as well as make more power.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl &raquo;</TD></TR><TR><TD CLASS="quote">I might want to raise the BS flag on this one

Most people don't realize that the S2000 piston actually goes inside the cylinder head to acomplish quench. The better burning allows it to pass smog easier as well as make more power.</TD></TR></TABLE>

Not to mention helping it achieve its 112% VE rating

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LeGeND4LiFe &raquo;</TD></TR><TR><TD CLASS="quote">I've heard of phenominal gains in detonation resistance from reshaping combustion chambers to promote faster burn characteristics. I talked to a guy who does this for people and on his AE86 street car, he said was he was running 14.9:1 compression on 87 octane on a built NA motor revving to 10k with no signs of detonation.


Modified by LeGeND4LiFe at 4:50 AM 3/10/2006</TD></TR></TABLE>

so what your saying is the head flows 80cfm thus allowing something so impossible to actually stay in one piece?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by R@mon &raquo;</TD></TR><TR><TD CLASS="quote">

so what your saying is the head flows 80cfm thus allowing something so impossible to actually stay in one piece? </TD></TR></TABLE>

huh

 

what i mean is that the only what he said is possible is if the motor couldnt breath in enough air to hurt itself, in other words, regardless of compression it couldnt draw in enough air to build sufficient cylinder pressure to matter.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl &raquo;</TD></TR><TR><TD CLASS="quote">I might want to raise the BS flag on this one

Most people don't realize that the S2000 piston actually goes inside the cylinder head to acomplish quench. The better burning allows it to pass smog easier as well as make more power.</TD></TR></TABLE>

Could be BS, I didn't see any proof of it, just what the guy said. And he is the one who sells the service, so who knows.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by R@mon &raquo;</TD></TR><TR><TD CLASS="quote">what i mean is that the only what he said is possible is if the motor couldnt breath in enough air to hurt itself, in other words, regardless of compression it couldnt draw in enough air to build sufficient cylinder pressure to matter.</TD></TR></TABLE>

That really has nothing to do with it. The idea is faster burn rate in the combustion chamber, allows less chance for detonation to occur, needs less timing advance, reduces losses and increases effiency. Endyn's roller wave pistons are based on the same idea. "Roller-Wave forced induction pistons incorporate full stepped-quench pads to maximize (mechanical octane)".

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LeGeND4LiFe &raquo;</TD></TR><TR><TD CLASS="quote">Could be BS, I didn't see any proof of it, just what the guy said. And he is the one who sells the service, so who knows.

That really has nothing to do with it. The idea is faster burn rate in the combustion chamber, allows less chance for detonation to occur, needs less timing advance, reduces losses and increases effiency. Endyn's roller wave pistons are based on the same idea. "Roller-Wave forced induction pistons incorporate full stepped-quench pads to maximize (mechanical octane)".</TD></TR></TABLE>

i understand perfectly, he wants to implement better squish into the cylinder by welding up the quench pads, im a big fan of Larry's work and i was simply pointing out that those claims of a 87 octane 15:1 compression 10k rpm motor were a bit outlandish.


Modified by R@mon at 2:12 PM 3/10/2006

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by R@mon &raquo;</TD></TR><TR><TD CLASS="quote">

i understand perfectly, he wants to implement better squish into the cylinder by welding up the quench pads, im a big fan of Larry's work and i was simply pointing out that those claims of a 87 octane 15:1 compression 10k rpm motor were a bit outlandish.</TD></TR></TABLE>

Well, knowing only compression ratio, octane level and 10k RPM doesn't really tell the story at all. I used to tun 14.5:1 CR in my old GSR NA setup. You can easily combat detonation by keep retarding the timing, but eventually too much timing would be pulled to render the higher compression useless in making power.

The AE86 could be running insane compression, but it could be running 12.0:1 instead and still make the same power on the same octane.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">

Well, knowing only compression ratio, octane level and 10k RPM doesn't really tell the story at all. I used to tun 14.5:1 CR in my old GSR NA setup. You can easily combat detonation by keep retarding the timing, but eventually too much timing would be pulled to render the higher compression useless in making power.

The AE86 could be running insane compression, but it could be running 12.0:1 instead and still make the same power on the same octane.
</TD></TR></TABLE>

could also be using some sort of injetion (alky/water)

 

Now this is what I was talking about! Again, I'm not just attempting to make insane amounts of power just from this alone - my main purpose of even considering welding (raising quench) is to improve the burn efficiency.

I don't plan on doing this myself, as I suck at welding.

I've been having a hard time finding price quotes for this.. Does anyone know of a good place that offers CC welding? OR, does anyone know of any aftermarket piston that will have a similar effect?

Thanks again for all the input...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">Well, knowing only compression ratio, octane level and 10k RPM doesn't really tell the story at all. I used to tun 14.5:1 CR in my old GSR NA setup. You can easily combat detonation by keep retarding the timing, but eventually too much timing would be pulled to render the higher compression useless in making power.

The AE86 could be running insane compression, but it could be running 12.0:1 instead and still make the same power on the same octane.</TD></TR></TABLE>

You're right, the kicker is that although the timing was retarded quite a bit, it wasn't due to detonation. It was because the faster burn rate required less timing and he gained power/torque as he retarded timing. He claimed he was actually was running this setup with spark advanced/retarded to MBTT timing, which happened to be quite a bit less than it was before the combustion chamber reshaping.

MrTodd,
Look at Endyn's Rollerwave pistons like mentioned above, and they would probably be a good place to talk to about welding the combustion chambers as well.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .Lloyd Braun &raquo;</TD></TR><TR><TD CLASS="quote">let us know what happens....


good to see some creative thinking here, would this be on a streetcar?</TD></TR></TABLE>

Yes, it is daily driven. But also I'm addicted to autocross, so I'm aiming for the most performance on the track... I want the turbo to spool FAST, combined with a linear (usable) power curve.

This will be on a B18B engine. I plan to build it up extensively. (bottom end and headwork) I'm most likely going to use a GT28RS (disco potato) turbo, with the smaller .62 A/R housing for the faster spool. I'm looking for anything and everything (in addition to extensive tuning) that will help combat detonation - I need the engine to kick ***, all while being reliable enough to use on road trips.

Again, thanks for all of the input everyone! I'll check out Endyn's site.

 

For those power levels of what a GT28RS could put out (300-350whp), you could probably just do it on a healthy stock motor with good tuning and still have it reliable and safe, while saving alot of money. I think fully building it and going to the extent of reshaping the combustion chambers etc would be overkill for your goals. You might look into a much simpler/easier form of added detonation resistance, like h20/alky injection, etc.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LeGeND4LiFe &raquo;</TD></TR><TR><TD CLASS="quote">For those power levels of what a GT28RS could put out (300-350whp), you could probably just do it on a healthy stock motor with good tuning and still have it reliable and safe, while saving alot of money. I think fully building it and going to the extent of reshaping the combustion chambers etc would be overkill for your goals. You might look into a much simpler/easier form of added detonation resistance, like h20/alky injection, etc.

</TD></TR></TABLE>

No such thing as overkill when it comes to having a reliable setup. That's how these factory turbo cars can pull off factory-like reliability off the showroom floor. The key is to super overbuilt the engine plus supporting components, and great examples would be most of the factory turbo cars such as Supras, STi's, etc...

The closer you kiss the limit of the engine, the less reliable it would be when surrounding components fail to keep up 100% like they should. Most guys won't even try to do a topspeed 5th gear pull on a Honda, but folks won't hesitate to do that say for a stock Lancer Evo... why? Honestly, I do 5th gear topspeed pulls all the time and I peg the **** out of the car for miles after miles (long highway trip to the track, no traffic for like 10 miles ahead on a 4 lane highway )

A built bottom-end, great tuning and let's say a welded chamber that improves combustion are definitely the ticket to a reliable and durable setup

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">No such thing as overkill when it comes to having a reliable setup.</TD></TR></TABLE>


My thoughts exactly... The best example of a 'properly' built turbo setup would come straight from the factory. If you don't believe me, take apart ANY factory turbo'd engine and see how bullet proof it is - there are plenty to choose from (ie mitsubishi, subaru, dodge, etc) I guarantee that each of these OEM motors would be built FAR superior to MANY people's (on this board) aftermarket turbo'd engines...

Personally, I think there is a common misconception about what you can and can't do with a turbo charged honda. I think turboing a honda REALLY grew in popularity after the famous "junkyard turbo" setup came into view - where any kid could build a complete setup for $1000 or less... While this can work for some, those of us who want to have a RELIABLE setup, with EXCEPTIONAL performance realize that you have to cover as many bases as possible to keep everything in working order. I'm not the average ricer who just wants to do stupid *** 'pulls' on the street, just to **** off the local community of other ricers. I don't race bitch asses from street light to street light. I have a goal with my car: race HARD at autocross, all while having a RELIABLE daily driver. My engine's going to have the **** beat out of it every weekend - I can't have it break down on me when I go to work the next day...

I'm still researching on how to build it, and it's still going to take a long time to put it all together. But in the end, I know it's going to be worth the time, effort and money. My car will be anti-junkyard turbo. Sorry homies.

Again, thanks for all of the comments!