nitrous V quench

{But we aren't looking at NA performance, we are looking at player N20 loads, 500 to 1500???? loads of N20 and fuel. Are we running into an issue where the standard fast burn small combustion chamber head from FORD suppliers is just too damn small for the amount of fuel??? The Chevy guys have combustion chambers of 90 to 120+CC in wedge head offerings. Are the players compensating for small combustion chamber volume and allowing player level fuel in by simply eliminating quench and making the head a large open chamber head with the use of head gaskets and or piston placement? }




so someone is paying attention to the problem fords small chamber.they are designed to burn fast causing a lot of heat ok for efficiency but not for large doses of nos.GM's large chamber is a bowl type design that helps keep the charge moor centered over the piston and slows the flame front down witch helps with quench better.

now saying that their is a level of nos in the Gm heads need help with the quinch.the heads are sent out and have a plunge or bowl cut in the chambers.i don't know what that level is I just know its above the fords.

my chambers have been softened with a 3* cut its been said that was a waste of money.it should have been some were around 7*+ some other work on the chamber.

Fwiw my pistons are .065 in the hole w a .045 thick gasket, 4.3 stroke and used a 6.7 rod so we could get a custom piston and move the ring stack as far down as possible. My 32 and 28 kits may not be a huge shot nut this deal has been trouble free.

[quote="richter69"]Fwiw my pistons are .065 in the hole w a .045 thick gasket, 4.3 stroke and used a 6.7 rod so we could get a custom piston and move the ring stack as far down as possible. My 32 and 28 kits may not be a huge shot nut this deal has been trouble free.[/quote

how far down is your top ring ?

10SHOTS wrote:

richter69 wrote:Fwiw my pistons are .065 in the hole w a .045 thick gasket, 4.3 stroke and used a 6.7 rod so we could get a custom piston and move the ring stack as far down as possible. My 32 and 28 kits may not be a huge shot nut this deal has been trouble free.[/quote

how far  down is your  top ring  ?

When the piston to head clearance is opened up you have more valve to piston clearance too. At that point have pistons made with shallower valve reliefs.....= stronger piston.

richter69 wrote:Fwiw my pistons are .065 in the hole w a .045 thick gasket, 4.3 stroke and used a 6.7 rod so we could get a custom piston and move the ring stack as far down as possible. My 32 and 28 kits may not be a huge shot nut this deal has been trouble free.

Did way better than my dumb ass....  built a nice NA  package.  But now know why it did what it did.   .003 out the hole and a .037" gasket.   Rings are .450 down.  I just didn't leave any room to put more stuff in the head.  50 cc combustion chamber aint helping.   

The more I learn the greater the assurance I don't know shit.

Seems the talk is all about the P51 chamber....well ...uh...I do not see how that exhaust port and valve size could service a 500 or 1,500 shot.

Keep talking about the chamber ..but ...if one can't get the heat out of the deal it aint gonna work.

20 degrees more exhaust bias on the cam?????

I've got 14 degrees more exhaust lobe on trick flow 325s and thinking about 18 degrees more to help with scavaging and to blow down some cylinder pressure , Ive been lifting the head and tearing Pistons up , ,
I'm thinking on trying this , 285-303 on a 114 lobe sep, 13.5 compesson , ring land down .400 top ring 1/16 .173 back cut , piston in the hole .020 with a .051 head gasket , .071 quench on a 400 shot , be it right or wrong I don't know , is it the 500-600 shots that need the .100 quench ?

all this talk about quench and small chamber heads, my brother has a 445 cid 9.5 deck small block with 56cc AFD 10 degree valve angle Cleveland heads zero deck with a .040 head gasket , 14.1 compression , 278-290 cam on a 110 lobe sep , head flows 350 and 230
shooting 300 on a  thrown together fogger , car is a 5 teen ride . motor is 4 years old and has 280 passes on it ,and he has not had any problems as of yet .  is it just a bbf ford head issue ?

Lem Evans wrote:Seems the talk is all about the P51 chamber....well ...uh...I do not see how that exhaust port and valve size could service a 500 or 1,500 shot.

Keep talking about the chamber ..but ...if one can't get the heat out of the deal it aint gonna  work.  

the p51 is what I have to work with even if we go with a different head the basic same chamber design is what we are stuck with the C head has a deeper chamber that keeps the charge moor centered to the piston but with the 3-10* angle after the valves is were the heat is coming from imo.their is not a bowl to keep or help slow the cooling process.

this is were the rule makers have the ford guys by the nutz by having head designs that are basically the same.

10SHOTS wrote:all this talk about quench and small chamber heads, my brother has a 445 cid 9.5 deck small block with 56cc AFD 10 degree valve angle Cleveland heads zero deck with a .040 head gasket , 14.1 compression , 278-290 cam on a 110 lobe sep , head flows 350 and 230
shooting 300 on a  thrown together fogger , car is a 5 teen ride . motor is 4 years old and has 280 passes on it ,and he has not had any problems as of yet .  is it just a bbf ford head issue ?

I don't think the ones who know or the ones who know better than WE want to put their cards on the table......

could some of it , In my case anyway maybe the cams just to small with nitrous , maybe it needs to be 288-302 on a 114 ,    the 445 small block is 117 cid smaller with a 278-290 on a 110 and the cam I've been using is a 284-298 on a 114 for a 562 cid , 445 has 165 pounds cranking compression and 562 has 190

the more i think the stupider I feel

I spray 350ish on my 321" sbf, no vac pump, no chamber softening, .060" quench..... Been that way for 2 seasons w no issues at all..... I dont even look at the plugs.... Deal just works

10SHOTS wrote:I've got 14 degrees more exhaust lobe on trick flow 325s and thinking  about 18 degrees more to help with scavaging and to blow down some cylinder pressure , Ive been lifting the head and tearing Pistons up , ,
I'm thinking on trying this , 285-303 on a 114 lobe sep,  13.5 compesson , ring land down .400  top ring 1/16 .173 back cut , piston in the hole .020 with a .051 head gasket , .071 quench on a 400 shot , be it right or wrong I don't know ,  is it the 500-600 shots that need the .100 quench ?

if your lifting the head you need to reflow your stuff chances are you shooting alot more than you think or your cam is not bleeding off the exhaust fast enough. you want to get the nitrous out as fast as you can sounds to me like you also need a better cam with more exhaust side..

I think its overtimed, cam and quench etc are not ideal but no reason to be having the issues you are with what you have.

gmsmkr wrote:

10SHOTS wrote:I've got 14 degrees more exhaust lobe on trick flow 325s and thinking  about 18 degrees more to help with scavaging and to blow down some cylinder pressure , Ive been lifting the head and tearing Pistons up , ,
I'm thinking on trying this , 285-303 on a 114 lobe sep,  13.5 compesson , ring land down .400  top ring 1/16 .173 back cut , piston in the hole .020 with a .051 head gasket , .071 quench on a 400 shot , be it right or wrong I don't know ,  is it the 500-600 shots that need the .100 quench ?

if your lifting the head you need to reflow your stuff chances are you shooting alot more than you think or your cam is not bleeding off the exhaust fast enough.  you want to get the nitrous out as fast as you can sounds to me like you also need a better cam with more exhaust side..

it's a IS direct port injection and was hitting it with a 350 shot

richter69 wrote:I think its overtimed, cam and quench etc are not ideal but no reason to be having the issues you are with what you have.

15 degrees total timing on a 350 shot is to much ? do I need to start at 13 or less

kim wrote:20 degrees more exhaust bias on the cam?????

Running a lot of exh. duration on a sprayed engine is not unusual , but it will not change the size. The heavy sprayed engines seem to like bigger headers so I'd think a smallish exh. valve and port would be a bottle neck.

10SHOTS wrote:

richter69 wrote:I think its overtimed, cam and quench etc are not ideal but no reason to be having the issues you are with what you have.

15 degrees total timing on a 350 shot  is to much ? do I need to start at 13 or less

I think hero is on something here lol..... with the quench you have and cam I would start the timing around 11 and bump up from there

10SHOTS wrote:

gmsmkr wrote:

10SHOTS wrote:I've got 14 degrees more exhaust lobe on trick flow 325s and thinking  about 18 degrees more to help with scavaging and to blow down some cylinder pressure , Ive been lifting the head and tearing Pistons up , ,
I'm thinking on trying this , 285-303 on a 114 lobe sep,  13.5 compesson , ring land down .400  top ring 1/16 .173 back cut , piston in the hole .020 with a .051 head gasket , .071 quench on a 400 shot , be it right or wrong I don't know ,  is it the 500-600 shots that need the .100 quench ?

if your lifting the head you need to reflow your stuff chances are you shooting alot more than you think or your cam is not bleeding off the exhaust fast enough.  you want to get the nitrous out as fast as you can sounds to me like you also need a better cam with more exhaust side..

it's a IS direct port injection and was hitting it with a  350 shot

The boom might not be the problem.  The amount of liquid in the cylinder could be enough your beating the head off hydraulicly.

If it were a methanol deal then hyd lock might be an issue........ Also if its lifting the heads the pistons aint gonna live no matter what.

Not a bad idea to add quench and maybe some exh duration...one thing id do when i went back out is pull 5 more degrees and go from there

richter69 wrote:If it were a methanol deal then hyd lock might be an issue........ Also if its lifting the heads the pistons aint gonna live no matter what.

Not a bad idea to add quench and maybe some exh duration...one thing id do when i went back out is pull 5 more degrees and go from there

ok I've talked to my cam guy , and he said the 284-298 114 lobe sep ain't getting the exhaust valve open early enough , he said the about the same thing Mr. Evans said , said my heads ain't good enough for  350 to 400 shot of spray on a 566 cid motor , he won't to put a 286-305 on a 115.5 installed at 113 and said don't get the compression over 13.5 but he would do 13.1 , do you think he's close on the new cam ?
I was thinking do the cam , 13.5 compression , Pistons .020 in the hole , .051 gaskets
I think he said the the exhaust will open at 92 or 95 degrees I can't remember

The P51 chambers are ~ in the center of the bore too, but I'm not in any way saying that the C460 & P51 are the same stuff.

Some of the advantages that the C460 casting has:
1] An exh. port that can flow 370 cfm.

2] I suspect that the bigger C460 casting holds one hell of a lot more water which makes it more tolerant of ign. timing even in a N.A. application. The casting also has the steam holes that match the ones in the A460 block's deck which may not be a huge deal but, certainly can't hurt either.

10SHOTS wrote:

richter69 wrote:If it were a methanol deal then hyd lock might be an issue........ Also if its lifting the heads the pistons aint gonna live no matter what.

Not a bad idea to add quench and maybe some exh duration...one thing id do when i went back out is pull 5 more degrees and go from there

ok I've talked to my cam guy , and he said the 284-298 114 lobe sep ain't getting the exhaust valve open wary enough , he said the about the same thing Mr. Evans said , said my heads ain't good enough for  350 to 400 shot of spray on a 566 cid motor , he won't to put a 286-305 on a 115.5 installed at 113 and said don't get the compression over 13.5 but he would do 13.1 , do you think he's close on the new cam ?
I was thinking do the cam , 13.5 compression , Pistons .020 in the hole , .051 gaskets
I think he said the the exhaust will open at 92 or 95 degrees I can't remember

I doubt that your 284* intake is much of an issue if any at all. I'm ~ on the same page as your guy relative to the exh. duration and lsa.....304* @ .050" and a wider lsa i.m.o.

Lem Evans wrote:

10SHOTS wrote:

richter69 wrote:If it were a methanol deal then hyd lock might be an issue........ Also if its lifting the heads the pistons aint gonna live no matter what.

Not a bad idea to add quench and maybe some exh duration...one thing id do when i went back out is pull 5 more degrees and go from there

ok I've talked to my cam guy , and he said the 284-298 114 lobe sep ain't getting the exhaust valve open wary enough , he said the about the same thing Mr. Evans said , said my heads ain't good enough for  350 to 400 shot of spray on a 566 cid motor , he won't to put a 286-305 on a 115.5 installed at 113 and said don't get the compression over 13.5 but he would do 13.1 , do you think he's close on the new cam ?
I was thinking do the cam , 13.5 compression , Pistons .020 in the hole , .051 gaskets
I think he said the the exhaust will open at 92 or 95 degrees I can't remember

I doubt that your 284* intake is much of an issue if any at all. I'm ~ on the same page as your guy relative to the exh. duration and lsa.....304* @ .050" and a wider lsa i.m.o.

he started out with a 283 intake lobe with a 305 ex then changed his mind for some reason