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Cam question for 67 GTX

neverenuf

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I just bought a 67 GTX.The engine is a 68 with 906 heads.It has a flat tappit hyd cam that has some bad lifters from sitting a long time.Been reading about the hyd roller cams,sometimes not working real good with worn lifter bores.Engine has low miles on a rebuild but it has sat for 4 years.So i'm going with the solid roller.I talked to compcams and they recommended street roller Xtreme energy Kit K-23-700-9 grind xr-274r.
I'm worried about it having enough vacuum for the power brakes.I'm looking for someone that is running/ran this cam,that can tell me how much vacuum it makes.I know every engine responds a different but would like to hear some real world answers.Thanks and looking forward to enjoying this nice ride.
gtx.jpg
 
Congrats on the beautiful car! Good luck with the cam choices. Don't be in a hurry.
 
I just bought a 67 GTX.The engine is a 68 with 906 heads.It has a flat tappit hyd cam that has some bad lifters from sitting a long time.Been reading about the hyd roller cams,sometimes not working real good with worn lifter bores.Engine has low miles on a rebuild but it has sat for 4 years.So i'm going with the solid roller.I talked to compcams and they recommended street roller Xtreme energy Kit K-23-700-9 grind xr-274r.
I'm worried about it having enough vacuum for the power brakes.I'm looking for someone that is running/ran this cam,that can tell me how much vacuum it makes.I know every engine responds a different but would like to hear some real world answers.Thanks and looking forward to enjoying this nice ride.View attachment 1241617

Yup, congratulations!
Some of the BIG guns here can help with the CAM choice
Budnicks
Cranky
Hemi-itis (He's fully Blown)
MarPar (Gorgeous 67 GTX)
I recently sold a 67 GTX, it was a project, my Bud bought it.
I put in the "440 Source" Roller Rockers
Some people like them, some do not....
Welcome aboard and thanks for joining the Forum

Remember: Many CAM companies offer a Great "Tech" line...
 
Just my thoughts here, but I would try some sea foam first and run it and see if the lifters quit making noise. After that pull the lifters and clean each one and put it back in the same spot and see if they work properly. An upgrade to a solid roller is a very expensive upgrade. Cam, roller lifters, adjustable rocker arms, new pushrods and some other small items. Can easily be in it for close to 3 grand if you choose top of the line parts.

edit: forgot to mention new valve springs/ hardware and the associated machining of the heads that may be needed as well if they are stock iron heads.
 
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A roller camshaft will require different length pushrods than what you would use on flat tappet. Are you staying with the stock rocker arms?
 
Solid roller may not be that good - that cam will be a bit lumpy.
I agree with earlier post check the current camshaft and lifters for unacceptable wear first.
Go from there if it is all torn up.
 
And I’m going to take a step back here and ask: what is the engine doing that makes you suspect bad lifters?
 
For starters, what has already been done to the engine and is it a four speed or automatic car? If it's an automatic, then what gears? Do you know anything about the cam in it right now (stock, aftermarket, etc.) A solid lifter cam is a good upgrade for a lot less than a solid roller. Before doing anything, you may want to look at the I.D. pad on the block for a diamond or a double diamond stamp which indicate O.S. lifters. Although rare to see, that can make things a lot more complicated than just a simple cam change.
 
I'd run that camshaft in that application. I would phone comp cams though and see if the lifters included are the good ones. Some lifters are better for high mileage street use than others, not sure about those particular ones. I will personally never again run a flat tappet camshaft unless the durability issues are fixed (queue in the "I've run flat tappets for 150 years and never had a failure" response now).
You may have to adjust with a better convertor but I'd try it with what you have now.
 
The 274xr should run the vacuum brakes. It's going to vary some with what compression you have.

If you are wanting to go solid roller it's very little more to do a custom. I would suggest talking to Tim Goolsby at bullet cams.
I think you would like a 112 or wider lsa cam better for your application. More vacuum smoother idle.
Rockers imo the mancini roller rockers are best bang for the buck.
 
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A roller camshaft will require different length pushrods than what you would use on flat tappet. Are you staying with the stock rocker arms?
Have to run adjustables,that is rocker arms
 
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I'd run that camshaft in that application. I would phone comp cams though and see if the lifters included are the good ones. Some lifters are better for high mileage street use than others, not sure about those particular ones. I will personally never again run a flat tappet camshaft unless the durability issues are fixed (queue in the "I've run flat tappets for 150 years and never had a failure" response now).
You may have to adjust with a better convertor but I'd try it with what you have now.
I have already talked to compcams,gave them what i have and the one i listed is what they recommended.I will personally never install a flat tappit cam again.Thanks for the heads up on the lifters
 
For starters, what has already been done to the engine and is it a four speed or automatic car? If it's an automatic, then what gears? Do you know anything about the cam in it right now (stock, aftermarket, etc.) A solid lifter cam is a good upgrade for a lot less than a solid roller. Before doing anything, you may want to look at the I.D. pad on the block for a diamond or a double diamond stamp which indicate O.S. lifters. Although rare to see, that can make things a lot more complicated than just a simple cam change.
I'm willing to spend the extra for a roller.I will check the block pad for that.I did not see any diamonds on it.
 
Just my thoughts here, but I would try some sea foam first and run it and see if the lifters quit making noise. After that pull the lifters and clean each one and put it back in the same spot and see if they work properly. An upgrade to a solid roller is a very expensive upgrade. Cam, roller lifters, adjustable rocker arms, new pushrods and some other small items. Can easily be in it for close to 3 grand if you choose top of the line parts.

edit: forgot to mention new valve springs/ hardware and the associated machining of the heads that may be needed as well if they are stock iron heads.
Thanks for the heads up on the sea foam.How much do you add?
 
Yup, congratulations!
Some of the BIG guns here can help with the CAM choice
Budnicks
Cranky
Hemi-itis (He's fully Blown)
MarPar (Gorgeous 67 GTX)
I recently sold a 67 GTX, it was a project, my Bud bought it.
I put in the "440 Source" Roller Rockers
Some people like them, some do not....
Welcome aboard and thanks for joining the Forum

Remember: Many CAM companies offer a Great "Tech" line...
Thanks for the info.I have spoken to compcams.
 
The 274xr should run the vacuum brakes. It's going to vary some with what compression you have.

If you are wanting to go solid roller it's very little more to do a custom. I would suggest talking to Tim Goolsby at bullet cams.
I think you would like a 112 or wider lsa cam better for your application. More vacuum smoother idle.
Rockers imo the mancini roller rockers are best bang for the buck.
Thanks for the info on the cam and rockers.I'm not real familiar with mopars but i was told not to go above 110 lsa.
 
I think it’s just a can of sea foam? Bottle should say as I’m not positive what ratio to oil quarts to use. As far a LSA goes, the majority of aftermarket cams are ground on the 110 lsa. The tighter the lsa is the lumpier the idle will be. 110 and lower is good for big engines and headers. Wider (112 and up) lsa is good for engines using manifolds.
 
Thanks for the info on the cam and rockers.I'm not real familiar with mopars but i was told not to go above 110 lsa.
If you are getting your info from comp cams...they are NOT mopar guys. If you are worried about your vacuum, widening the lsa WILL have more vacuum and idle better, and not fall off as much on the big end. Most of the factory high performance cams were done at 113-115.. It is true a narrower lsa can bring the power in sooner and help mid range, but its at a cost of driveability.

I would also suggest visiting with Hughes engines. They do only mopars, they have a lot of knowledge, and generally won't sell junk. They also like to sell narrow lsa cams if that is the direction your convinced you want to go. Comp cams unfortunately has sold a lot of sub par stuff, especially when it comes to lifters. But, we still run some of there products. Comp does not build the same quality that they once did. But they certainly are not the only ones that have lowered the bar.
 
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To take a set of factory iron castings, rebuilt to perfection to oem specs, and wanted to properly set them up for a solid roller cam....... the parts and labor for that upgrade will be the in the $1100 range.
That’s just for the heads, assuming they are basically perfect to start with(but set up like oem).

Cam, lifters(suitable for extended periods of street use), rockers, pushrods, oil pump drive gear, 3 bolt timing set, thrust button, gaskets, etc........ another $3000 or so.

My .02 is...... if the plan is to drive the car a fair amount...... a solid roller isn’t a good choice.
 
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All of what I have posted is based off of my own experience. I have a hydraulic roller in my engine. Against all the stuff I read and advice I was given against it…I did it anyways. Would I do it again? No. I did it due to being naive mostly and not wanting to listen and take in the advice I was being given. Mr. Porter (PRHeads) actually is the one who helped me with my cam selection, and ordered it for me.

my engine is a 493, pistons sit .047 in the hole. 440 source aluminum heads, which I changed the springs and retainers all by myself. Not really knowing what I was doing. The cam is a hyd roller ground on a 113 lsa, and somewhere in the 236/246 duration at .050 lift if I recall the cam card correctly. I wanted to run stock HP manifolds. I have the Hughes aluminum roller rockers and their hyd roller lifters. I put together the engine myself and it runs good in my opinion. Could it be better? Yes. Would headers help? Yes, probably could gain around 40-50 hp just by switching to headers. So again, would I do the whole roller thing again? No, probably would go with a hyd flat tappet and make sure I got good quality lifters and ran the correct oil.
 
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