[Zeder]

Hello,
Has anyone tried to put a GM roller Hot Cam in a pre 87 SBC. I have come across the cam for free, so if I invest in a set of Roller Lifters I should be able to use it. Has anyone tried this cam in a carburated engine. I was going to go with the Edelbrock Perf RPM heads/intake/1406 carb/1.6RR and the Edelbrock Roller lifters. DD2000 make it look like a nice package but I would rather hear it from someone who has had real world success with it!
Cheers,
Zeder

 

[Siggy_Freud]

What are the cam specs? Do you have a retrofit kit too?

I would go with a different carb. The 1406 was economy calibrated from the Edelbrock factory.

 

[edge]

GM Hot Cam

The Hot Cam specs should be 218/228 @ 0.050, .525/.525 lift (w/ 1.6 rockers), w/112* lsa.

I do not believe that you can use that factory roller style cam (step nose) in a non-roller block (pre-87').

This is a "step nose" cam and as such it requires a special timing chain sprocket. To retrofit a roller cam in a pre-87' block requires a thrust button to keep it from walking forward. Since a "step nose" cam uses a retainer plate bolted to the block to keep it from walking, the timing chain will not accommodate a thrust button. Without a thrust button, you cannot use this cam in a non-roller block (pre-87'), since the block does not have the bosses and machining to attach the retainer plate.

Also, in a non-roller block, you need to use retro-fit lifters that employ a link bar between two adjacent lifters to keep them from rotating. These run about $300 and up.

I hope that all makes sense, Ed www.edgesz28.com

 

[Zeder]

Thanks for the Info Edge. I read somewhere that I can cut the tabs off the cam retainer I currently have and then buy a cam button retainer clip for the cam. I have seen the retainer clip and it just looks like a piece of stamped steel. It look like it just bolts to the front of the cam. I was going to use the Cloyes Quick change timing cover. It has a screw on the front of the cover to allow cam end play adjustment. I already have the edelbrock hydraulic roller lifters. I found a new set on Ebay for a great price. Link bar type. I will need to do the cam button thing and probably use a different timing chain. I currently have a true double roller but I can't remember what type it is, and its still in the car with a flat tapper EX250H cam, so I don't know if it will work. The specs for the cam look fairly mild. definitely longer duration than the cam I am currently running, more lift too. I am looking to make good torque up to 5600 or so. All of this is going into a 2 bold main block so I really don't want to buzz it too high. My concern with the Hot Cam is it is normally in a computer controlled engine. My fear is that the computer helps it along with smoothing out the idle. My "dumb" little carb might make it a little ruff at idle. I don't know!
Edge - do you have any updates as to you ET / HP with your setup?
Cheers,
Zeder

 

[edge]

All of this is going into a 2 bold main block so I really don't want to buzz it too high. My concern with the Hot Cam is it is normally in a computer controlled engine. My fear is that the computer helps it along with smoothing out the idle. My "dumb" little carb might make it a little ruff at idle. I don't know!
Edge - do you have any updates as to you ET / HP with your setup?
Cheers,
Zeder

1. 2-bolt: No problem for your setup and 6,000 RPM, which is as high as you'll ever want to take that cam anyway.

2. I would not be concerned with that cam in a carb setup. Check out Deuce's 32 Roadster (ZZ430) at this thread, third post down. He could probably give you some insight as to its manners. Give him a PM if he doesn't see this thread.

3. Updates on my car, not yet. I will this spring. However, with the temps in the mid-70's recently, I wouldn't be suprised if the tracks have re-opened early.

Good luck with trying that cam in the non-roller block. Maybe it can be done, but I would not know how to do it. I suppose if you can figure out a way to employ a thrust button with the step-nose sprocket, it will work. It can't hurt to try since the cam was free. If it doesn't work out, you can still go hydraulic roller, it will just cost you more money. But what else is new (lol). I stopped keeping track years ago. My wife every now again reminds me whenever I complain about her spending habits.

Ed www.edgesz28.com

 

[edge]

Now You Got Me Thinking!

Alright, this may be a little dangerous, but you've got me thinking about this more than I probably should (lol).

I found two articles from Chevy Hi Performance regarding roller cams and the different designs and accessory requirements. Both have good pictures depicting what has already been said:

1. Roll it Over
2. Don't Walk!

The first article talks about putting a factory roller cam in a pre-87' block and that it can be done, but you have to cut off the tangs on the original retainer plate. Other than that, there is no detail. The second article has some good pictures of the thrust buttons I was talking about.

I talked to my engine builder about this and he thinks it can be done, but the hardest part will be getting a thrust button to work with the upper sprocket of the factory roller timing chain. The reason you cut off the tangs and keep the original retainer plate is to maintain the proper alignment of the two timing chain sprockets. It will be nothing more than a spacer plate between the cam and upper sprocket. You may even be able to get a torrington bearing to install in lieu of the old retainer plate.

As far as the thrust button goes, if the hole in the upper sprocket is the same diameter as an early style sprocket, you are good to go. If not, you will need have one machined to fit, probably out of brass. It does not have to be a roller button. I prefer the nylon buttons from Comp Cams. You may even be able to use the nylon button and carefully sand down the diameter if the hole is too small in the late model sprocket. Either way, to adjust the end play with a nylon button, you sand the engine side (bigger end) ever so slightly until the proper end play is achieved (like .005"). You may even be able to use the Cloyes two-piece cover with built in thrust button.

Without actually having the two different upper sprockets to compare, I am unable to verify if the thrust button will work without issue. Maybe someone else can answer that for you. Either way, I am now sure that you can use that free cam in the non-roller block. Be sure to let us know how it works out.

Good luck, Ed

 

[Zeder]

Hey Ed,
Thanks for the info! I like the Cloyes cover. I will have to measure the step diameter on the end of the cam. I see that gm perf parts has 2 different ones available. I can't remember which one will work. I will have to get one of these. I think the reason I can't reuse my current timing chain is because the 3 hole in the end of the cam are closer to the center because of the step. Your comment about grinding the tabs off of the OEM retaining plate is making me think now, will the modified retaining plate spin with the cam? Also, I wonder what will happen if the rear cam plug in the block was not installed far enough or too far. This would offset the entire cam, No? I just talked to a Cloyes tech guy, he said I can use the 2 piece cover but I will have to custom fit the button with the timing gear. He said I might have to turn the end of the button on a lathe. I think it would be easier to open up the hole in the sprocket. I think the cam button is hardened, the upper sprocket is not. Either way it look like I will have to do some hot rodding I will also have to get one of those custom fuel pump drives too. The Don't Walk article is the first I have heard of this. $$$ is starting to add up. The only reason I am going this way is because of a lack of foresight. If I would have know I was going to do this I would not have rebuilt my pr387 block. Oh well! I seem to always be out of the mainstream with things like this. Keeps it interesting though, just $$$ sometimes!
Cheers
Z

 

[jimfulco]

The Hot cam has a fuel pump lobe, so you can use a regular mechanical pump if you want to. You will need the GM melonized distributor gear (PN 10456413), though.

As far as idle quality, I recently heard a 350 with Hot cam & a carb setup and it had just a slight bit of roughness to it, not even enough to really call it a lope.

http://www.sdpc2000.com/catalog/540...-Duration-0_050-Hydraulic-Roller-Camshaft.htm is the Hot cam.

 

[Zeder]

Right on! Thanks Jim! I was wondering what the idle sounds like. This setup is going into a bit of a sleeper. It also confirms to me that with a little roughness, not a lope, I should also get decent vacuum. I was wondering about the melonized gear. Thanks for the link to www.sdpc2000.com The warranty issue pretty much spells it out! I will need one! So do they throw big melon's at that gear or what)