AFR Heads again!
Melting Slicks
Joined: Mar 2003
Posts: 2,472
Likes: 0
From: Toronto ONTARIO
here's what i did to check my pcv. i went on the highway and pulled from 2nd to 4th to redline. In 4th gear i let it deccelerate in gear and slowed to a stop. i pulled the pcv tube from the Tb and literally a quarter litre of oil peed all over my valve cover from inside of it.
Melting Slicks
Joined: Jun 2002
Posts: 2,152
Likes: 241
From: Northern VA
Guess I'll jump in here too. I am having the decel smoke issue. I am down a quart every time I take the car out. Compression and leak down test out ok. Pull the plugs...look fine. I too put a compressor filter inline on the pcv line and it fills pretty quick. The motor runs good at puts out great power. I have Brodix heads milled from I believe 68cc to 66cc. That I guess could be an intake fitment issue. I also am running a high volume, high pressure pump. Can't keep the v/c's sealed either. hmmmm I will be watching this thread!
Thread Starter
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Originally Posted by DieL
pcv
pcv
pcv
pcv
If you're talking high rpm decel trust me I know what problem you are having. Decceleration from 8000 rpm in gear I was blowing tons of smoke out the pipes. Again Now that my missing oil problem is solved by removing the pcv there's no smoke as well.
pcv
pcv
pcv
If you're talking high rpm decel trust me I know what problem you are having. Decceleration from 8000 rpm in gear I was blowing tons of smoke out the pipes. Again Now that my missing oil problem is solved by removing the pcv there's no smoke as well.
Drifting
Joined: Aug 2001
Posts: 1,500
Likes: 0
From: Holliston MA
Cruise-In VII Veteran
Here's one for you all. If an engine has all the same oil hemorage points and if a high and low volume pump both operate at the same pressure, why would the high volume pump be putting any more oil into the top of the motor. Wouldn't the high volume pump just be bypassing more oil back into the oil pan.
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
the high volume pump most assuredly does add pressure, not like a high pressure pump, but the volume increase also has the effect of a pressure increase, and that goes right up to the top.
i'm seriously thinking of removing the melling HV pump and going back to a stock unit. i can't hurt at all, and may possibly help. while i'm okwith 1 qt use per 1,000 miles, i sure would like to improve upon that. it certainly won't make a hit with a potential buyer when i tell him it "consumes" oil at any rate.
if my builder would have consulted me, i would have told him "no". with all new bearings, the works, a HV pump is overkill unneccesary. make me wonder about the builder. i'm a silly stooge though, myself.
i'm seriously thinking of removing the melling HV pump and going back to a stock unit. i can't hurt at all, and may possibly help. while i'm okwith 1 qt use per 1,000 miles, i sure would like to improve upon that. it certainly won't make a hit with a potential buyer when i tell him it "consumes" oil at any rate.
if my builder would have consulted me, i would have told him "no". with all new bearings, the works, a HV pump is overkill unneccesary. make me wonder about the builder. i'm a silly stooge though, myself.
Last edited by Red Tornado; Oct 11, 2006 at 10:31 PM.
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
Originally Posted by tjwong
One issue would be if the oil is pooling around the valves, and if the
oil drains are an issue the with crankcase pressure high it could force
oil through the valve guides easily. AFR is even telling me to swap out
to a standard volume pump now, but its still hard for me to believe it's
just that.
oil drains are an issue the with crankcase pressure high it could force
oil through the valve guides easily. AFR is even telling me to swap out
to a standard volume pump now, but its still hard for me to believe it's
just that.
Could a tin valve cover, a Sawzall, plexiglass, sealant
and some pop rivets open a window on your world?
.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
The guys on ThirdGen.Org are having a similar discussion about the new AFR Eliminator heads, oil oling, quality contol issues, etc. Be warned, it's may pages long.
Check it out; may find some answers there.
Jake
Check it out; may find some answers there.
Jake
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Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Tom,
Another thought...we know that we will have some pressure in the cylinders by pass the rings and therefore increase the pressure that is in the pan. Now apply 12+ additional pounds of boost into the cylinders.
1) Could the ring gaps be miss aligned? What does a compression test say?
2) Are different rings or more of them used in REAL high performance race engines? or is this a matter that who cares if you blow out a quart of oil in 1/4 mile in 4-6 seconds.
3) I can see that machining the head to eliminate the pooling around the spings would help eliminate oil going around the guides. The next problem would be how do we get more oil back into the pan. Could the oil return holes be increased in size. Even so, we are still are using gravity to return the oil vs the pump pushing oil up top. Would there be some way to drill and tap the head on the low side and run external oil return lines back to the pan. (Just what you need...more lines in limited space)
Another thought...we know that we will have some pressure in the cylinders by pass the rings and therefore increase the pressure that is in the pan. Now apply 12+ additional pounds of boost into the cylinders.
1) Could the ring gaps be miss aligned? What does a compression test say?
2) Are different rings or more of them used in REAL high performance race engines? or is this a matter that who cares if you blow out a quart of oil in 1/4 mile in 4-6 seconds.
3) I can see that machining the head to eliminate the pooling around the spings would help eliminate oil going around the guides. The next problem would be how do we get more oil back into the pan. Could the oil return holes be increased in size. Even so, we are still are using gravity to return the oil vs the pump pushing oil up top. Would there be some way to drill and tap the head on the low side and run external oil return lines back to the pan. (Just what you need...more lines in limited space)
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
Originally Posted by DieL
here's what i did to check my pcv. i went on the highway and pulled from 2nd to 4th to redline. In 4th gear i let it deccelerate in gear and slowed to a stop. i pulled the pcv tube from the Tb and literally a quarter litre of oil peed all over my valve cover from inside of it.
Diel: if oil going through VC's and leading to TB but where this oil goes ?. it stays in TB and intake plenum or it goes back to oil sump? or gets burned through exhaust?.
I have a similer situation 1 qt every 1000 miles only if i drive like i stole it otherwise upon normal driving not too much step on, it burned may be roughly 500ml every 1000 miles. I have a brand new pvc's. I did found very minimal oil on driver side VC when i pulled the hose out of it though but it was dry on passenger side hose, i checked this in morning before going work though. I have a Dart 200cc heads with new valve seals and new valve train stuff. No smoke at all and compression test is perfect on all cylinders. Car runs awesome and its stout built by pete k (thanks pete).
I have stock style i think M55 oil pump too. oil pressure never goes below 58 psi at any time.
Just bought a K N breather will be put on in few min's.
Last edited by sami85L98; Oct 12, 2006 at 01:01 AM.
. 
Instructor
Joined: Mar 2003
Posts: 187
Likes: 0
From: Aztec NM
I'm in the same boat
My LT1 383 runs excellent but uses about a quart every tank of gas (250-350 miles) around town. A few plugs show a little oil, but most don't. It will smoke when I hammer it, but for the most part, no smoke. I had intake problems earlier, the front and rear of the intake were bottoming out on the block, but I think I fixed it. I had a broken plastic valve cover so when I replaced it I got another RH one so I could put a breather in both of them, so I don't think crankcase pressure is a problem. I still have a PCV, but I was having the same problem before I put it back in. I'm going to yank it and see if something changes.
I would have thought that it would be much easier to use that much oil past the rings than the heads. My heads are Doug Rippie ported LT1s, but I have a really nicely ported LT4 top end wrapped up in plastic waiting to put in. From what I've heard in this thread, I'm a little nervous about putting them in.
I used Mobil 1 when I built the engine, my machinist said that could have kept my rings from seating, but I haven't used it about 15,000 miles, It's built loose for the supercharger, but my cold leak down is less than 10% on all of them and 5 are less than 5%. I'm almost to the point of yanking it and re-ringing it, but hopefully the answer will miraculously appear here soon.
I would have thought that it would be much easier to use that much oil past the rings than the heads. My heads are Doug Rippie ported LT1s, but I have a really nicely ported LT4 top end wrapped up in plastic waiting to put in. From what I've heard in this thread, I'm a little nervous about putting them in.
I used Mobil 1 when I built the engine, my machinist said that could have kept my rings from seating, but I haven't used it about 15,000 miles, It's built loose for the supercharger, but my cold leak down is less than 10% on all of them and 5 are less than 5%. I'm almost to the point of yanking it and re-ringing it, but hopefully the answer will miraculously appear here soon.
Drifting
Joined: Oct 2005
Posts: 1,259
Likes: 0
From: bakersfield cali
it's interesting that a lot of you are having the same issues. sound like a design flaw.
it's also interesting that tony mamo has a thread in this same section and he hasn't posted in here.
it's also interesting that tony mamo has a thread in this same section and he hasn't posted in here.
Pro
Joined: Nov 2004
Posts: 637
Likes: 0
From: Perth Amboy N.J.
Tom
When I was having my engine built, I had a new set of AFR LT4 heads. A while back on this forum I read about this oil problem with AFR heads. I call Tony at AFR and talked to him about this problem. I didnt want to go through this problem I was reading about. Tony told me to send the heads back and gave me a full refund. Now I use Stock LT4 ported out heads by Port Pros in Tx and a balanced oil pump. Tom, ask Greg (Blower Works) about my engine.
Regards Gene
When I was having my engine built, I had a new set of AFR LT4 heads. A while back on this forum I read about this oil problem with AFR heads. I call Tony at AFR and talked to him about this problem. I didnt want to go through this problem I was reading about. Tony told me to send the heads back and gave me a full refund. Now I use Stock LT4 ported out heads by Port Pros in Tx and a balanced oil pump. Tom, ask Greg (Blower Works) about my engine.
Regards Gene
Last edited by bacardioil; Nov 14, 2006 at 10:01 PM.
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
TPIS mills a trough by the bottom rail out similar to J.Burnetts fix. It has a little pooling at the rear still under the vc seal and very little at the springs, stock pump and all seems well. I get a little oil in the pcv, but the pcv is built in a breather so it has a catch can type of effect (most of it stays in breather cap and doesn't get sucked up the tube).
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
Mick, did you see what TPIS is charging for their AFR/TPIS heads these days? Its jaw-dropping. I can't believe they sell for $2350 for L98/$2650 for LT1. I'm glad I paid $650 less for the L98 head, 2 years ago. Still sky-high. They advertise 54cc chambers, but mine were measured at 56cc. The one big thing about them, they're ready right out of the box. No milling or massaging needed. Thats a big plus too.
Melting Slicks
Joined: Dec 2000
Posts: 2,719
Likes: 60
From: Fremont Oh
Originally Posted by tjwong
Hi People. I have an issue with a motor that has a set of AFR 210 LT4 heads on it. My customer and fellow forum member is telling me that he is using up to 2 quarts per one hundred miles if you goes out and runs the car HARD for those 100 miles. From what I have seen and heard that their is an issue with the AFR heads returning oil to the sump. I know and my engine builders feel that there is NO WAY that the engine can pass that volume of oil past the rings. My feeling is that some how its passing the oil through the valve guides. The last time I had the engine apart the heads were inspected and new viton rubber seals were installed as a safety measure. However its still consuming the oil during spirited driving sessions.
Glen has since sent the spark plugs back to me for inspection. I don't feel that there is that kind of consumption based on just what I see on the plugs. I feel that the oil is being sucked in through the valve guides during high RPM decceleration and blown out throught the exhaust. If this engine was using that kind of oil and actually burning it, the plugs would have fouled long ago.
Now here is what AFR tells me. With out acknowledging any actually problems with their heads. They feel that because we have a high volume high pressure oil pump in the engine. That oil is being pumped into the upper part of the engine (heads) and because it can't return as fast as its being feed that oil is pooling in the valve spring pockets and being sucked into the cylinders and blown out under high RPM decceleration conditions.
My question is, has anyone else experienced this kind of problems. I have taken the engine apart personally, and checked the internals out myself before the machine shop replaced the rings and honed the cylinders for the second time. New valve seals were also installed at that time and the engine continues to use oil. My own car has a similar engine with AFR 195s but I have a stock volume oil pump with a high pressure spring.......so any one out there with issues such as this??
Glen has since sent the spark plugs back to me for inspection. I don't feel that there is that kind of consumption based on just what I see on the plugs. I feel that the oil is being sucked in through the valve guides during high RPM decceleration and blown out throught the exhaust. If this engine was using that kind of oil and actually burning it, the plugs would have fouled long ago.
Now here is what AFR tells me. With out acknowledging any actually problems with their heads. They feel that because we have a high volume high pressure oil pump in the engine. That oil is being pumped into the upper part of the engine (heads) and because it can't return as fast as its being feed that oil is pooling in the valve spring pockets and being sucked into the cylinders and blown out under high RPM decceleration conditions.
My question is, has anyone else experienced this kind of problems. I have taken the engine apart personally, and checked the internals out myself before the machine shop replaced the rings and honed the cylinders for the second time. New valve seals were also installed at that time and the engine continues to use oil. My own car has a similar engine with AFR 195s but I have a stock volume oil pump with a high pressure spring.......so any one out there with issues such as this??
I'm also running AFR 210's as you well know.... I also have a melling HV pump.... I'm still going through probably more oill than i should be. I probably have close to 10K on the engine now.
Glenn posed the question to me, I really didnt think about it until he bought it to my attention....
It seems to me that if I'm doing high spirited runs I'm going through a lot of oil , seems like I'm using at least a quart as well... I have been writing it off as blowing it out the breather ( which I still need to resolve) it appears most of mine is being blown out the breather... I'm sure most is from the S/C pressurizing the crankcase. I have not noticed any smoke on decel... I'm running one of Greg's special PVC valves...
I really haven't seen any oil pooling...
I have just changed plugs the other day and they looks like they have been burning clean.
If there is anything I can look for or at that may help you please let me know...
MO
Burning Brakes
Joined: Jun 2000
Posts: 1,148
Likes: 48
Originally Posted by Hot Rod 90
Mick, did you see what TPIS is charging for their AFR/TPIS heads these days? Its jaw-dropping. I can't believe they sell for $2350 for L98/$2650 for LT1. I'm glad I paid $650 less for the L98 head, 2 years ago. Still sky-high. They advertise 54cc chambers, but mine were measured at 56cc. The one big thing about them, they're ready right out of the box. No milling or massaging needed. Thats a big plus too.
I didn't know they had issues like that.
The car does pull like a **** so I'm trying to resolve these issues. I'm going to remove the PCV tube, reweld the roofs of he exhaust ports and see how that does.
Funny thing is the exhaust ports were mildy done and have lots of meat on them left yet two ports leaked none the less.
Pretty sad.
Pro
Joined: Nov 2004
Posts: 637
Likes: 0
From: Perth Amboy N.J.
Mo
Thats the problem I talked with Tony at AFR about. Never got a real answer, so I sent the heads back. I think I made a wise move. Its the pooling around the valve guides and returns for the oil. Mo, as you know I have no kinds of problem with oil. I,am sure the HV pumps are helping the problem. Thats also the reason I stayed with the Canton balance oil pump. Chevy never had any oiling problem with their oiling systems in a small block, why dose everyone use HV and HP pumps. Media plays a big part in why everyone uses HV and Hp pumps.
Regards Gene
Thats the problem I talked with Tony at AFR about. Never got a real answer, so I sent the heads back. I think I made a wise move. Its the pooling around the valve guides and returns for the oil. Mo, as you know I have no kinds of problem with oil. I,am sure the HV pumps are helping the problem. Thats also the reason I stayed with the Canton balance oil pump. Chevy never had any oiling problem with their oiling systems in a small block, why dose everyone use HV and HP pumps. Media plays a big part in why everyone uses HV and Hp pumps.
Regards Gene