Help! AFR pushrod problem
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Racer
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From: Tennessee
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St. Jude Donor '06-'07
Help! AFR pushrod problem
If you guys have been following my other post about my 540 finally finished....well I guess its not. The engine shop called today and told me the intake pushrod clearance was too far off to fix with adjustable guide plates and gave me two options 1) Tear the engine back down and cut the pushrod holes bigger which would probably mean new head gaskets (cometic $$) 2) or go with T&D shaft mounts that they told me they could order with offset pushrod cups and not have to remove the top end. If I went with the T&D set-up I would go with 1.75 to raise my lift from .632 to .651 which would put my beehives at their limit. The cost of removing the top-end and machining the holes and reassembly was 500.00 the T&D set-up was quoted at 1200.00 intstalled and set-up. I know the T&D shaft set up is overkill for my application, but would probably be a good idea if I go to a solid roller later. What do the experts recommend?
Last edited by TNBUSA; Dec 8, 2006 at 09:43 PM.
Team Owner
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Down at the race shop we ran into a simular problem of the push rods rubbing against the head pushrod holes.
This was caused by too great of an angle directly outboard (not side rubbing. They installed taller ARP studs, longer pushrods, and lash caps to keep the roller tip centered on the valve stem.
If you have a side deflection problem. You can install offset roller lifters and or rockers to center the pushrod in the hole.
It also costs less to remove the heads and do some die grinding than to spend $1200 on a shaft setup
This was caused by too great of an angle directly outboard (not side rubbing. They installed taller ARP studs, longer pushrods, and lash caps to keep the roller tip centered on the valve stem.
If you have a side deflection problem. You can install offset roller lifters and or rockers to center the pushrod in the hole.
It also costs less to remove the heads and do some die grinding than to spend $1200 on a shaft setup
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
How come that's your problem and not the shops problem ? If they are assmebling the motor then they gotta check everything and clearance everything before torquing things down.
Personally I would probably go with the shaft rocker setup, at least you are gaining something that way and not just giving them 500 bucks to be back at the same place you are now
Personally I would probably go with the shaft rocker setup, at least you are gaining something that way and not just giving them 500 bucks to be back at the same place you are now
Melting Slicks
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From: Mo
they mite be able to grind them without removing the heads,but rags in the valley and have someone hold a vacumn right below where there grinding to suck it up right way.kinda like a dentist sucks the **** out before you swallow it.
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From: Taylor Michigan
Just exactly what are adjustable guide plates? If everything is correct why would you need them. Guide plates come in 3 sizes. 5/16, 3/8 and 7/16 for the size of the pushrods. Also i`m sure that your aware pushrods come in several different lengths for both valves and if too short may cause interferance and also the rockers to hit the retainers.
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Racer
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St. Jude Donor '06-'07
Hey motorhead! its my problem because im the dummy that assembled the top-end and took it to them to fix it, its also my problem because I have to pay for it
Gkull, I am suppose to call them back monday and let them know which way to go and will ask them about the longer studs. Thanks for the ideas. Anybody else have any better ones?
Gkull, I am suppose to call them back monday and let them know which way to go and will ask them about the longer studs. Thanks for the ideas. Anybody else have any better ones?
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Racer
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St. Jude Donor '06-'07
Ironcross, adjustable guide plates are two piece and are held together with a allen bolt in the center. Apparently the pushrod problem is common on aftermarket heads....esp AFR. I read on this forum about the issue or probably would not have checked as close as I did but I already had everything bolted down. Thank goodness for this place or it could have been worse.
Race Director
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From: Taylor Michigan
Originally Posted by TNBUSA
Ironcross, adjustable guide plates are two piece and are held together with a allen bolt in the center. Apparently the pushrod problem is common on aftermarket heads....esp AFR. I read on this forum about the issue or probably would not have checked as close as I did but I already had everything bolted down. Thank goodness for this place or it could have been worse.
Wally Knoch `
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Racer
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From: Tennessee
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St. Jude Donor '06-'07
Ironcross, AFR (air flow research)heads have been around a long time. They are known for flowing lots of air compared with other heads with the same size runners. I should of checked the clearance during the trial assembly but did not....it even said to check it in the instructions. If I would of done this I would have simply enlarged the pushrod holes and went on my way. Its really not that big of deal, its just I had everything bolted up....transmission etc... and was getting ready to drop it in when I read on a post here about the pushrod deal. So, while adjusting the valves I checked it and the intake pushrods were rubbing the head. I have been working on this thing for three years and its been one thing after another. I guess im just getting impatient, I was getting ready to smoke some tire and now another set-back.
Pro
Joined: Aug 2003
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From: Victoria Texas
TNBUSA, are you dealing with Chad at Eagle Racing?
They are very good folks, we run one of there 706 ci outlaw Pro-Mod engines, Fastest nitrous outlaw pro-mod in Texas.
That bunch knows how to make serious power.
They are very good folks, we run one of there 706 ci outlaw Pro-Mod engines, Fastest nitrous outlaw pro-mod in Texas.
That bunch knows how to make serious power.
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Two ways I know to do this....
I think you said they have Cometic gaskets under them. Generally the best deal of them is that they are supposed to reusable since they are a multipiece steel shim. So since this bad boy hasn't been cranked yet, I'd go down there and pull the heads off myself, clean gaskets up real good, do your clearancing and then use sealer on gaskets to reinstall them for insurance.
The other choice is to invest in LOTS of duct tape and paper. and go to town with the grinder while heads are in place. I can tell you it makes a heck of a mess (Huh ML67???) but it does work. You need to cover everything super well. I use shaving cream to fill ports and other holes and stuff. It catches metal great, then I use a shop vac to suck it all out along with the shavings. You WILL need to spend a couple of hours cleaning everything else up.....but it can be done.
Since engine is out of car, I vote for the removing the heads method unless it's just one pushrod or so..which I doubt.
Even with shaft stuff, you will need to do some clearancing most likely.
JIM
I think you said they have Cometic gaskets under them. Generally the best deal of them is that they are supposed to reusable since they are a multipiece steel shim. So since this bad boy hasn't been cranked yet, I'd go down there and pull the heads off myself, clean gaskets up real good, do your clearancing and then use sealer on gaskets to reinstall them for insurance.
The other choice is to invest in LOTS of duct tape and paper. and go to town with the grinder while heads are in place. I can tell you it makes a heck of a mess (Huh ML67???) but it does work. You need to cover everything super well. I use shaving cream to fill ports and other holes and stuff. It catches metal great, then I use a shop vac to suck it all out along with the shavings. You WILL need to spend a couple of hours cleaning everything else up.....but it can be done.
Since engine is out of car, I vote for the removing the heads method unless it's just one pushrod or so..which I doubt.
Even with shaft stuff, you will need to do some clearancing most likely.
JIM
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Racer
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From: Tennessee
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St. Jude Donor '06-'07
Skid, yea im dealing with Chad, he and Mike for sure know there stuff, they have been great to deal with. Hey Jim! I think im just going to call them monday and have them do just that....pull heads and grind the holes. I already used spray sealer on the cometics so dont know if they will clean-up. Thanks for your help everyone! Mike
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From: Lenoir City Tennessee
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Any news on how they are coming along? I have to work next week then I am off until after the 1st. If they get it done, maybe we can get it put in one of those days.
