AFRs and oil drainback issues...
Thread Starter
Pro
Joined: Sep 2004
Posts: 690
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From: Madison WI
AFRs and oil drainback issues...
Well, after the reading a couple threads about this, I thought I'd ask here to get some kind of definitive response. I know AFR heads have had some troubles with oil drainback and therefore brand new motors becoming oil burners...and I really would rather not deal with that this summer when I do my H/C/I, but AFRs are awesome performers and in my price range. How widespread is the problem and has it been fixed yet? I know last year an AFR rep posted about it and how they were hoping to solve the problem; will I be safe to buy a pair of 180s this summer? What if they are burning oil when I get 'em - will AFR fix it?
Racer
Joined: Sep 2005
Posts: 453
Likes: 1
From: Austin TX
I ordered a set of custom 180s back in Septemeber and recieved them in December, but I have yet to install them. Needless to say "things" are taking longer than I thought. They are still brand new in the box and I WILL be installing them this summer. I sure hope there are no oil drain back issues.
Burning Brakes
Joined: Oct 2004
Posts: 763
Likes: 0
From: Loveland Colo
OK, I'll add my "I dunno yet" also.
Bought my 180s over a year ago, they're only going on this next week. As far as I could tell from photos and talk, the problem seemed to be the proximity of the seats & springs to the edge of the head & gasket area, thus not providing a good drain trough. My 180s have a nice 5/16" or so space here, so it seems they should be OK. However I did take them to the machine shop to check the valve/seat concentricity which is another problem I've heard of them having. While there the guys will relieve the drain holes a bit and use their discretion as to the drain problem. (They will also get .020" milled off to get my compression where I want).
Will they work worthy of their cost? I do not know yet, but if I were to do it over again I would look at Brodix or Dart a lot closer....Do some more searching here and at Hotrodders.com also.....Here's a link to a discussion: http://www.hotrodders.com/forum/what...?highlight=AFR
I'll hopefully have good news about them in a couple weeks....
John
Bought my 180s over a year ago, they're only going on this next week. As far as I could tell from photos and talk, the problem seemed to be the proximity of the seats & springs to the edge of the head & gasket area, thus not providing a good drain trough. My 180s have a nice 5/16" or so space here, so it seems they should be OK. However I did take them to the machine shop to check the valve/seat concentricity which is another problem I've heard of them having. While there the guys will relieve the drain holes a bit and use their discretion as to the drain problem. (They will also get .020" milled off to get my compression where I want).
Will they work worthy of their cost? I do not know yet, but if I were to do it over again I would look at Brodix or Dart a lot closer....Do some more searching here and at Hotrodders.com also.....Here's a link to a discussion: http://www.hotrodders.com/forum/what...?highlight=AFR
I'll hopefully have good news about them in a couple weeks....
John
Safety Car
Joined: Oct 2004
Posts: 3,926
Likes: 739
From: Youngstown Ohio
I've had AFR 195's over 2 years now, and have not had any oil drainback issues. However, there have been some people who have, and AFR has acknowledged and have made improved oil drain passages in their new heads. I briefly saw them advertised, but can't recall which magazine I was breezing through. I suggest calling them and talking to a tech, as I have always found them helpful and accommodating.
Thread Starter
Pro
Joined: Sep 2004
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From: Madison WI
Originally Posted by C3 Stroker
I've had AFR 195's over 2 years now, and have not had any oil drainback issues. However, there have been some people who have, and AFR has acknowledged and have made improved oil drain passages in their new heads. I briefly saw them advertised, but can't recall which magazine I was breezing through. I suggest calling them and talking to a tech, as I have always found them helpful and accommodating.
Melting Slicks
Joined: Feb 2006
Posts: 3,428
Likes: 5
From: Japan
Oil Pump?
One thing to consider with the drainback issue is just how fast your engine pumps the oil to the top end. I put a Melling Hi-volume pump on the first motor I ever built (about 15-16 yrs. ago as I recall...)-it was (of course) a mild 350 SBC. It started right up but before I could even think about breaking in the cam oil started leaking out of the breathers like a wringing wet rag....I later learned that even with hydraulic cams these pumps put out way more volume than the heads can drain back; the only way to run an HV pump is with oil restrictors installed in the oil galleys to the crank. You probably already knew this, but it's just a thought-AFR heads are pretty popular and of course (as are HV oil pumps) used primarily in performance applications- I'm sure I'm not the only fool that learned this one the hard way(I finally did go back to a stock pump).
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Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Originally Posted by birdsmith
One thing to consider with the drainback issue is just how fast your engine pumps the oil to the top end. I put a Melling Hi-volume pump on the first motor I ever built (about 15-16 yrs. ago as I recall...)-it was (of course) a mild 350 SBC. It started right up but before I could even think about breaking in the cam oil started leaking out of the breathers like a wringing wet rag....I later learned that even with hydraulic cams these pumps put out way more volume than the heads can drain back; the only way to run an HV pump is with oil restrictors installed in the oil galleys to the crank. You probably already knew this, but it's just a thought-AFR heads are pretty popular and of course (as are HV oil pumps) used primarily in performance applications- I'm sure I'm not the only fool that learned this one the hard way(I finally did go back to a stock pump).
Hi volumn oil pumps are the problem, not the solution. I have heard of them pumping so much oit to the top the bottom doesn,t get enough oil. I am going with the Mellings 10% pressure increase oil pump on my build.
Racer
Joined: Sep 2004
Posts: 424
Likes: 2
I have 195s and I don't have an oil burning issue, but I do have a leakage issue, from the breathers and the gaskets. I agree that it seems to be from to much oil to the top, I am also using a Melling HiPo pump. I believe the complaints were from the larger race heads, 210s. But I believe that drain back can and needs to be improved. Call AFR and ask about this, last year they said they were planning to address issue.
Drifting
Joined: Dec 1999
Posts: 1,462
Likes: 1
From: Reno nevada
If AFR has released it's new casting design with higher valve cover rails and include some kind of drain back trough so the seals aren't in a oil pool all the time. I believe that they are quality designs as far as port flow goes.
Every one of the small block heads had the valve cover gasket swimming in oil every time you start the motor. Where superior casting like the Brodix and Dart you could idle the motor with a stud girdle in place and not even have the valve cover on. AFR would have the oil running over the side and down the block on the hot headers.
So most people that bought AFR just knew ahead of time that they required additional machining once they recieved them. It's just an added cost to the heads. Performance isn't cheap.
Every one of the small block heads had the valve cover gasket swimming in oil every time you start the motor. Where superior casting like the Brodix and Dart you could idle the motor with a stud girdle in place and not even have the valve cover on. AFR would have the oil running over the side and down the block on the hot headers.
So most people that bought AFR just knew ahead of time that they required additional machining once they recieved them. It's just an added cost to the heads. Performance isn't cheap.
Safety Car
Joined: Jul 2001
Posts: 3,921
Likes: 2
From: York PA
The only problem I have with mine is the oil at the back of the engine pools up against the gasket. This makes it very difficult to keep them from leaking. Next time I have them off I will probably have them machined to fix this problem. The fix was posted here with pictures a while ago, hopefully I can find the thread when I need it. 
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
I think it was Gkull that had some major issues with AFR heads. I don't know if or how it was ever resolved, but I know he tried various things working with the AFR reps and was ready to throw them in the river. That may be the thread you're thinking of and I think that was when the AFR rep posted here.
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
I'm referring to a thread from about a year ago (around 04/15/05). It was Gkull. It was about his AFR 210's. He and Tony Mamo from AFR really got into it. Again, I don't know how it eventually was resolved, but he was pretty hot about it at the time (understandably so). He could not get them to stop smoking.
Last edited by 79MakoL82; Apr 25, 2006 at 01:00 PM.
Melting Slicks
Joined: Dec 2001
Posts: 2,025
Likes: 1
From: Billings MT
SmokedTires had some oil consumption issues. The problem is with the hieght of the material around the spring pad, the spring bads are cut ~1/2" into the top of the head and there is very little rail for oil return so the oil pools around and flood the valve guides, not to mention returns along the gasket.
I had my heads off for a freshen up this winter and we put them in a mill cut a channel for oil return along the outside of the head.
I had my heads off for a freshen up this winter and we put them in a mill cut a channel for oil return along the outside of the head.
Melting Slicks
Joined: Jun 2002
Posts: 2,844
Likes: 99
From: Orrtanna Pa.
I also have run the AFR 195's now for four years and had no issues with oil comsumption. As stated in earlier posts,I too had discovered the HV oilpump issue,and now use a standard Chevy pump. I did install a Moroso 7qt kickout pan to insure adequit volume at high rpms.
I would not have the nerve to have milled a return drainback channel in $1500. heads. You're cahone's are definately bigger than mine.
I would not have the nerve to have milled a return drainback channel in $1500. heads. You're cahone's are definately bigger than mine.
