Where to start

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1930

1930

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I am confused on where to start. Just recently I was told that I needed to start with choosing a cam.......the first step.

I am now back to working on trying to get one of the cam manuf. reps to work with me but so far I have been told by various companies that I needed to know all sorts of internal engine stats before they could recomend a cam. Things like compression, head chamber size ect. I feel like I am chasing my tail.

Here below is my story at this point.

I have a 1986 W-100 ( 4 wheel drive ) Dodge truck with a N.P 435 trans ( manual ) and 3.55 gears. Am currently running 33s but may go with 35s.

It is powered by its original slant six engine. I searched for a long time for a truck with this drivetrain combination. Pictures of the trucks restoration can be seen here http://ramchargercentral.com/vehicle-help/1986-dodge/msg1867195/#msg1867195

I am a bodyman of roughly 30 years by trade.

I had the engine re-built, .040 over on the cylinders, stock cam, head gone thru and shaved a bit for better compression. Stock one barrel 1945 carb.

Machinist used cheap off the shelf engine kit, ( that was my second mistake ) I believe he didnt get it timed right when he assembled so truck still has never run correctly.

It currently has approx 18 miles on its re-built engine.

I am in the middle of going thru the engine again. The engine is still in the truck and I do not want nor see any reason to remove it at this point but what I would like to do is up-grade the bolt on items.

So far I have collected an entire Super six set-up, a Rollermaster double roller timing chain, a NOS Super six dist and valves that are a bit larger over stock along with new 340 valve springs that I may or may not use.

I am very eager to do some head work, intake/exhaust manifold work to optimize flow.

I am looking for some guidance on how to approach the build. I do not want to be regretful that I could have done something now while it is apart again.

I am not trying to build a speed demon, I would like the option of it being a daily driver but at this point its just a toy.

I would like to maximize the engines efficiency, I would like to WOW people when I open the hood in that the little slant six operated so well.

I would like great fuel economy considering what I am pushing along.

I would like to retain a stock appearance, I like original stuff, I am not interested in fuel injection, HEI or turbos or anything of that kind for this build.

I have several slants and I plan to explore all of those things with my next build.

I dont know where to start, I have alot of differemt opinions, I dont want to start in the middle and again be regretful cause I made a decision now which limits a decision that I had the option of making later on if that makes sense.

I am hoping someone can say start here and then move onto here and so on.

I have purchased a second truck just cause it had a slant in it and it is being used as a test-bed. It is low to the ground and scratching the paint is not an issue.

Anything I put on this truck can be taken off and run on my 86 once I have everything dialed in ( especially my skills/knowledge)

Suggestions welcome on how to proceed and why would be appreciated. The why is important cause I am getting so many different opinions off and on-line and Id like to make my own decision based on sound judgement, not just cause someone told me so.

Thank-you for your time
 
I think that we should try to get 9.0 - 9.5 compression for your engine, that's why we're working on that with the other thread.

as far as cams go, contact Dave Crower from Crower cams. He did a nice custom grind for my ex wife's slant 6 for her 64 Dart. It was 260° duration and .495" lift. He's really helpful and will work with you to get a nice cam for your build.


http://www.crower.com/


Crower Cams & Equipment Co., Inc.
6180 Business Center Court
San Diego, CA
92154-5604

Customer Service Hours
Monday-Friday 7am-5pm.
Phone 619.661.6477
Fax 619.661.6466


Go to this page and fill out the form and then ask for Dave to contact you to pick out a grind for your application:

http://www.crower.com/contacts/
 
Since your engine has the head off, you can check things and know where you stand. You have checked Deck Height. I would now find TDC and mark that on your Vibration Damper. They can be way off. The most important thing with any engine is the valve job. The most important thing about a valve job is to seal the valve to the seat, and keep the seat as high as possible, period. It does not matter what equipment or how many angles were used. Check them by Lapping a couple valves at random, intake and exhaust, on both heads. CC your chamber(s) then calculate Compression Ratio. The simple ratio, not measuring volume, not all the nits, you are not a Class Racer. If you want mill the head, you can mill up to .090 of an inch on a slant 6. Maybe check that, since yours is that new... Then call your Cam Company and tell them whatever they ask for. Do a bowl blend, Match the intake and exhaust ports to the gaskets if you want, cc and equalize the chambers if you want. You will love how your slant runs.
 
First: Are you carbing or using forced induction? If carbing, then get the compression up. If blowing, leave it low. Then it is a matter of matching-up the right components that work together: cam/carb/manifold/headers according to the RPM you want to run, the gears you have, etc. The guys on Slantsix.org recommend Oregon Cam grinders for price, knowledge and selection, but of course others know their stuff too. /6 .org has an entire table of cam grinds from OCG.

P.S.- If you decide not to use the 340 springs, let me know, I may have a buyer for you. :D
 
krazykuda said:
I think that we should try to get 9.0 - 9.5 compression for your engine, that's why we're working on that with the other thread.

as far as cams go, contact Dave Crower from Crower cams. He did a nice custom grind for my ex wife's slant 6 for her 64 Dart. It was 260° duration and .495" lift. He's really helpful and will work with you to get a nice cam for your build.


http://www.crower.com/


Crower Cams & Equipment Co., Inc.
6180 Business Center Court
San Diego, CA
92154-5604

Customer Service Hours
Monday-Friday 7am-5pm.
Phone 619.661.6477
Fax 619.661.6466


Go to this page and fill out the form and then ask for Dave to contact you to pick out a grind for your application:

http://www.crower.com/contacts/
Click to expand...

I think you are absalutly correct and yes thanks again for that other thread, you are being a big help for me.

BTW I was able to speak with the tech guy at Erson cams and he told me that the second to the last thing I want to buy for my engine is the camshaft, he said buy that right before the air cleaner.

He said build the engine the way I want it and then choose a cam that suits the engine but to keep in mind that I do not want to do anything to the engine that is going to hinder using a cam with a max lift of 450 degrees.

I am going to guess he was reffering to material removed from the head or block.
 
66fs said:
Since your engine has the head off, you can check things and know where you stand. You have checked Deck Height. I would now find TDC and mark that on your Vibration Damper. They can be way off. The most important thing with any engine is the valve job. The most important thing about a valve job is to seal the valve to the seat, and keep the seat as high as possible, period. It does not matter what equipment or how many angles were used. Check them by Lapping a couple valves at random, intake and exhaust, on both heads. CC your chamber(s) then calculate Compression Ratio. The simple ratio, not measuring volume, not all the nits, you are not a Class Racer. If you want mill the head, you can mill up to .090 of an inch on a slant 6. Maybe check that, since yours is that new... Then call your Cam Company and tell them whatever they ask for. Do a bowl blend, Match the intake and exhaust ports to the gaskets if you want, cc and equalize the chambers if you want. You will love how your slant runs.
Click to expand...
You must have read my mind cause finding TDC was on my list of to-dos for the weekend.
User my68barracuda was trying to explain to me in one of my threads how to do this, I did not understand what he was getting at but after talking with another gear-head on telephone and his explaining to me how to make the tool to do this I am clearer now on what barracuda was saying.
 
LTOP said:
First: Are you carbing or using forced induction? If carbing, then get the compression up. If blowing, leave it low. Then it is a matter of matching-up the right components that work together: cam/carb/manifold/headers according to the RPM you want to run, the gears you have, etc. The guys on Slantsix.org recommend Oregon Cam grinders for price, knowledge and selection, but of course others know their stuff too. /6 .org has an entire table of cam grinds from OCG.

P.S.- If you decide not to use the 340 springs, let me know, I may have a buyer for you. :D
Click to expand...
Carb, entire super six set-up including the BBD carb. I am trying to match up the right components as best as I know how
 
From what I saw you have all the right tools to do TDC. All you need is a magnetic base and a dial indicator. You have those, correct?
 
66fs said:
From what I saw you have all the right tools to do TDC. All you need is a magnetic base and a dial indicator. You have those, correct?
Click to expand...
Yes I have these things but I have been told that these are not the most reliable cause of deflection on the tool as the piston is pushing against it. Evidently there is some sort of strap that bolts across the cylinder bore and a sort of stop is screwed into the middle of it and this stop is adjustable. I was told to go on Summit site to get a better idea of what the tool looks like.

I was told the tool was easy to make.
 
66fs said:
Is the head off?
Click to expand...
Yes, evidently this is the tool. I will make one at the shop tomm

pro-66799_ml.jpg
 
1930 said:
Yes I have these things but I have been told that these are not the most reliable cause of deflection on the tool as the piston is pushing against it. Evidently there is some sort of strap that bolts across the cylinder bore and a sort of stop is screwed into the middle of it and this stop is adjustable. I was told to go on Summit site to get a better idea of what the tool looks like.

I was told the tool was easy to make.
Click to expand...


What you are referring to is the dead stop method for finding TDC.

This way you put a stop in the cylinder (they make a tool for the spark plug hole for this also). Then you install a degree wheel and pointer and rotate the engine until it stops. Record the reading, then reverse the crank direction and turn it untill it stops. Then record the reading.

Then split the two readings to get TDC.

*********************************************************************

The other way to find TDC is:

Install the dial indicator on the block and make sure that it is parallel to the cylinder bore. Turn the engine over and watch the dial indicator to see where it stops and then reverses direction. Keep spinning the crank in the SAME direction and watch it come up on the next stroke. Stop turning the crank when the dial indicator reaches the peak position before reversing. You may need to turn the engine over a few times to get it exactly, just keep turning in the same direction.
 
1930 said:
I think you are absalutly correct and yes thanks again for that other thread, you are being a big help for me.

BTW I was able to speak with the tech guy at Erson cams and he told me that the second to the last thing I want to buy for my engine is the camshaft, he said buy that right before the air cleaner.

He said build the engine the way I want it and then choose a cam that suits the engine but to keep in mind that I do not want to do anything to the engine that is going to hinder using a cam with a max lift of 450 degrees.

I am going to guess he was reffering to material removed from the head or block.
Click to expand...



Yes, follow his direction if he is who you are going to use for a cam. They have been posting a bit here trying to get some customers, I'm interested to see how their new stuff runs.


But not literally install the cam before the air cleaner, you should always check piston to valve clearance.

I recommend getting two head gaskets, so you can torque one to check piston to valve clearance, then use the other to build the engine. Save the one for checking piston to valve clearance for our final compression check/verification.

And lift for a cam is in inches. The duration is in degrees (that is how long the valve is open while the crank turns). Lift and duration are two main specs for a cam, then there are a few others that come into play also.
 
krazykuda said:
Yes, follow his direction if he is who you are going to use for a cam. They have been posting a bit here trying to get some customers, I'm interested to see how their new stuff runs.


But not literally install the cam before the air cleaner, you should always check piston to valve clearance.

I recommend getting two head gaskets, so you can torque one to check piston to valve clearance, then use the other to build the engine. Save the one for checking piston to valve clearance for our final compression check/verification.

And lift for a cam is in inches. The duration is in degrees (that is how long the valve is open while the crank turns). Lift and duration are two main specs for a cam, then there are a few others that come into play also.
Click to expand...
No I know he was not speaking literally.

I need to also check lifter pre-load evidently if any kind of significant material is removed from the head. I do not know how to check this yet.
 
You already have precision measuring equipment. There is no reason to get a special tool. Place the dial indicator perpendicular to the piston top, near the center since you have flat top pistons. Rotate the crank clockwise till you get to max travel and Zero your dial indicator. Now rotate the crank till the dial indicator reads .030, Any number larger than .015 will do, and mark your Vibration Damper. Next rotate the crank counterclockwise till you get to .030 and mark your Vibration Damper. TDC is the center of these two marks.

At .450 lift I doubt you will need to check valve clearance, but it can't hurt. I like your choice of intake and Carb.
 
1930 said:
No I know he was not speaking literally.

I need to also check lifter pre-load evidently if any kind of significant material is removed from the head. I do not know how to check this yet.
Click to expand...



I only like to mill the heads/block only enough to true them up. If I need to adjust compression, I will do that with the pistons.
 
66fs said:
You already have precision measuring equipment. There is no reason to get a special tool. Place the dial indicator perpendicular to the piston top, near the center since you have flat top pistons. Rotate the crank clockwise till you get to max travel and Zero your dial indicator. Now rotate the crank till the dial indicator reads .030, Any number larger than .015 will do, and mark your Vibration Damper. Next rotate the crank counterclockwise till you get to .030 and mark your Vibration Damper. TDC is the center of these two marks.

At .450 lift I doubt you will need to check valve clearance, but it can't hurt. I like your choice of intake and Carb.
Click to expand...
Its ok, I purchased a nice depth gauge in original wooden box ( remember when things came in nicely crafted wooden boxes :) ) that arrived today.

Cost me 20.00 plus shipping and Id date it from the late 40s early to mid 50s so I got a new toy to play with.

Im not out anything.

EDIT: I was confusing tools, depth gauge I purchased, thats not the TDC tool. Ok I am clear now. Thanks again
 
1930 said:
How will you do that with the pistons?
Click to expand...

I find out how much compression height that I need for the piston (by measuring my heads, gasket, and old piston set up). Then I measure the compression height of what I am starting with (center of wrist pin bore to the top of the piston), then figure out how much I need to add to get to my desired compression.

Then look for the correct height pistons if they are available, or see if custom ones are affordable.
 
Ok I understand. As far as I know aftermarket pistons ( higher compression performance pistons ) are not avail for the slant six. I am sure custom could be had but I do not want to get into all of that if I can help it.
 
before you rebuild the engine again, i'd like to know more info about the carb.

the bottom end generally dont make the engine run wrong unless he got the timing gears way out of whack but that's pretty hard considering they have little arrows to line them up. even with the 4% manufacturing variance or whatever it is, that wont make the engine run bad. possibly if you used the old cam i could see issues. was the cam a new stock cam or just the old one?

i'm guessing it was a new stock cam and that he installed the timing gears correctly. not perfectly tuned unless you degree the cam but still, this would not make the engine run real bad, it would just be missing a few horsepower that you could get back by optimizing the cam timing

that being said you more than likely have a distributor problem or carb problem.

out of those two i would lean toward the it being carb problem.

the reasons are #1 you probably have an old gas tank with crap in it. #2 the carb is probably not new. #3 if a carb is old or not rebuilt right the truck wont run right. heck even a lawnmower with a bad carb wont run right, and those are a whole lot simpler than automotive carbs.

just my 2 cents
 
moparlover said:
before you rebuild the engine again, i'd like to know more info about the carb.

the bottom end generally dont make the engine run wrong unless he got the timing gears way out of whack but that's pretty hard considering they have little arrows to line them up. even with the 4% manufacturing variance or whatever it is, that wont make the engine run bad. possibly if you used the old cam i could see issues. was the cam a new stock cam or just the old one?

i'm guessing it was a new stock cam and that he installed the timing gears correctly. not perfectly tuned unless you degree the cam but still, this would not make the engine run real bad, it would just be missing a few horsepower that you could get back by optimizing the cam timing

that being said you more than likely have a distributor problem or carb problem.

out of those two i would lean toward the it being carb problem.

the reasons are #1 you probably have an old gas tank with crap in it. #2 the carb is probably not new. #3 if a carb is old or not rebuilt right the truck wont run right. heck even a lawnmower with a bad carb wont run right, and those are a whole lot simpler than automotive carbs.

just my 2 cents
Click to expand...

At this point Im not sure what the problem was at the time and may never know. At this point I am having a good time where I am at with it right now learning what I need to know with everyone here and slant.org

Maybe in the meantime I will find something that was way off but so far no luck
 
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