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Got my monster cam for the beast today! This will give me .766/.792 lift with 1.6 shaft rockers, and 268/284 deg duration at .05 with 108 deg LSA. I'll be advancing it 5 deg when I install it with 50mm (1.968) roller bearings.
Got my monster cam for the beast today! This will give me .766/.792 lift with 1.6 shaft rockers, and 268/284 deg duration at .05 with 108 deg LSA. I'll be advancing it 5 deg when I install it with 50mm (1.968) roller bearings.
I'm curious as to why the large split between the intake and exhaust duration as the AFR's have good exhaust flow or did you make a typo? Who made the cam form you?
I'm curious as to why the large split between the intake and exhaust duration as the AFR's have good exhaust flow or did you make a typo? Who made the cam form you?
The exhaust flow is not that good, compared to the intake. Another factor is the intake piston to valve clearance with the cam advanced 5 deg it's lower on the intake than exhaust, so I was able to increase the exhaust lift and duration. Comp Cams made this for me after giving them the specs I wanted.
Here's a better shot at the DSS GSX 4.185 bore pistons with .322 valve relief pocket depth to give me 9.9:1 static compression ratio with my 9" deck and 4.125 stroke, and 5.95 connecting rods, with 0.05 compressed head gasket, and -16cc piston dome volume.
I got thinking about the camshaft I got for my engine upgrade and was losing sleep thinking about whether it would fit without the connecting rods striking it. It sure is a good thing my dart iron eagle block has the .391" raised cam, making it 4.912" from crankshaft to camshaft centerlines. I wrote a matlab script that I'll be putting in my EngineBuilderProfessional program soon to include this check. My camshaft is 1.968" (50mm) diameter and with my stroke of 4.125" and connecting rod length of 5.95", here's a plot showing the clearance. In the building tool I'll determine the minimum clearance and alert the user if not sufficient. This one has a clearance of .1587", and according to consensus, .06" clearance would suffice, so I should be good, but I'll check it of course when I assemble to make sure my calculations are accurate.
This next plot shows what would be the result if I didn't have the raised cam in my block.
Just for kicks, I entered the stock 350 engine stroke of 3.48, camshaft diameter of 1.868, connecting rod length of 5.7, and standard crankshaft to camshaft distance of 4.521 and got the following plot. The clearance is about the same order as my build at .1762
Last edited by bdhulderman; 07-22-2017 at 02:48 PM.
Ok, updated the website to reflect the new connecting rod to camshaft clearance estimation, with updates to the software to calculate the minimum clearance, and display the position of both at the minimum clearance, to help with determining where to shave the connecting rod if clearance is too tight. This plot is for the LS-7 engine, based on information available online.
Does anyone know the actual LS-7 clearance?
I assumed here 4" stroke, 6.067 connecting rod length, 4.890 crank to cam centerline, and 2.165 cam journal size.
Got a lot done today. Drained all the fluids, pulled the plugs and distributor, pulled the driveshaft, which is always a bear with having to take apart one of the 1350 series u-joints, pulled the 100+ pound Richmond 5-speed, which was a breeze compared to doing it on the ground before I put in my lift, and pulled the Centerforce Dual Friction Clutch. Tomorrow I'll need to pull the aluminum flywheel and see if I can get the block pulled, and get to work disassembling. I hope my cherry picker is still in good enough shape.
I got thinking about the camshaft I got for my engine upgrade and was losing sleep thinking about whether it would fit without the connecting rods striking it. It sure is a good thing my dart iron eagle block has the .391" raised cam, making it 4.912" from crankshaft to camshaft centerlines. I wrote a matlab script that I'll be putting in my EngineBuilderProfessional program soon to include this check. My camshaft is 1.968" (50mm) diameter and with my stroke of 4.125" and connecting rod length of 5.95", here's a plot showing the clearance. In the building tool I'll determine the minimum clearance and alert the user if not sufficient. This one has a clearance of .1587", and according to consensus, .06" clearance would suffice, so I should be good, but I'll check it of course when I assemble to make sure my calculations are accurate.
This next plot shows what would be the result if I didn't have the raised cam in my block.
Just for kicks, I entered the stock 350 engine stroke of 3.48, camshaft diameter of 1.868, connecting rod length of 5.7, and standard crankshaft to camshaft distance of 4.521 and got the following plot. The clearance is about the same order as my build at .1762
Well I don't know what the LS7 has for rod to cam clearance but I recall the thumb rule for rod to cam is 0.050". And it's more convincing to me at least to verify it physically with a home made gauge. You need to find some thing that looks like a zip tie but 0.050" in thickness and rotate the assembly to verify clearance. They used to be called tape gauges but are really just 12" long feeler gauges. And you have time trim them legthwise to which can Or you could clay a rod with 0.050" thick layer also. But I guess you want to verify all the rods have 0.050" clearance, not just one.
Quite a tedious process for a street motor.
Good luck.
Last edited by cardo0; 08-13-2017 at 01:46 PM.
Reason: Stupid autocorrect! Changed it so much I can't recall what I posted!
Well I don't know what the LS7 has for rod to cam clearance but I recall the thumb rule for rod to cam is 0.050". And it's more convincing to me at least to verify it physically with a home made gauge. You need to find some thing that looks like a zip tie but 0.050" in thickness and rotate the assembly to verify clearance. They used to be called tape gauges but are really just 12" long feeler gauges. And you have time trim them legthwise to which can Or you could clay a rod with 0.050" thick layer also. But I guess you want to verify all the rods have 0.050" clearance, not just one.
Quite a tedious process for a street motor.
Good luck.
Yes, I heard .06 is reasonable, so we're in the ballpark. I was curious how accurate my estimates were for the LS-7 (.098") given the specs I outlined above for it. According to the specs on what I'm building I'll have .159, so I have a warm fuzzy I'll be good enough to build. Then I'll check after assembly just what the clearance really is.
Well, my cherry picker held up well enough to pull the block out. I did have to remove the pan and oil pump to clear the body, but now on the engine stand, I can get to work stripping it down. You can see the "Iron Eagle" stamp and Victor Jr. heads that I had on it. And now have the block stripped. I didn't see any unusual wear or damage of any kind, which is good, considering I race it occasionally at the track and otherwise run the heck out of it. LOL Next weekend I'll put the block in the back of the truck and bring it down to the local machine shop with the crank, connecting rods, and pistons, and my new 50mm cam bearings to balance and bore it out another .02 to 4.185 and line bore the cam tunnel for the 50mm bearings.
Last edited by bdhulderman; 08-13-2017 at 10:23 PM.
Yea I have 3 blocks now waiting for overhaul but mine are OEM so nothing really fancy or expensive for builds. I found only one machine shop in town that does thermal cleaning of engine blocks. But I can tell I'll need to jump between machine shops to get the work done that I want even though my builds will be fairly basic. And I've met performance shop owners in this town that won't get any work on their blocks done here and send them all the way to LA.
Anyways I'm collecting tools and equipment and looks like I'll cough up $75 just for a straight edge. That should keep the machine shop straight, er honest. . I think I can improvise a drill press vise to R&R rod bolts. Whatch'a think? Pretty sure that will get'm out but not sure if it can work to press the bolts back in.
But what I'm really getting at is I found a nice 440lb electric hoist at HF for well under 100 bucks. I want to set up a rig to lift and drop the crank while fitting it up in the block. That 50lb crank is not forgiving to my back or scratches on the journals. I want to set something up overhead with the nice little electric hoist. But no-one else does this so I'm on my own creating something above the engine stand to rig the crank in and out w/o damage. If you have any ideas here let's hear them.. At least if they are ideas and not to sarcastic.
Yea I have 3 blocks now waiting for overhaul but mine are OEM so nothing really fancy or expensive for builds. I found only one machine shop in town that does thermal cleaning of engine blocks. But I can tell I'll need to jump between machine shops to get the work done that I want even though my builds will be fairly basic. And I've met performance shop owners in this town that won't get any work on their blocks done here and send them all the way to LA.
Anyways I'm collecting tools and equipment and looks like I'll cough up $75 just for a straight edge. That should keep the machine shop straight, er honest. . I think I can improvise a drill press vise to R&R rod bolts. Whatch'a think? Pretty sure that will get'm out but not sure if it can work to press the bolts back in.
But what I'm really getting at is I found a nice 440lb electric hoist at HF for well under 100 bucks. I want to set up a rig to lift and drop the crank while fitting it up in the block. That 50lb crank is not forgiving to my back or scratches on the journals. I want to set something up overhead with the nice little electric hoist. But no-one else does this so I'm on my own creating something above the engine stand to rig the crank in and out w/o damage. If you have any ideas here let's hear them.. At least if they are ideas and not to sarcastic.
Good night and good luck.
Wow, I had no idea Vegas area is so lacking in complete machine shops, if that's where you're still at. That's a shame. I guess I'm more fortunate in Tucson; at least we have a few good ones. I was so glad I put in my lift, because I'm not getting any younger either. It sure does beat trying to pull stuff on the ground. I also have a good compressor and air tank/air tools, which really speeds up disassembly. It sounds like you may have plan with the hoist if your back is having trouble. I'm sure stiff today from lifting stuff the last few days, but am grateful I still can function. I wish you the best in your builds, and hope you find a solution to installing the hoist.
So, I still had my Engine Analyzer Pro trial running on my old XP computer, and thought I'd check my new engine build specs with it to see how close it is to my engine building software tool. Turns out, it's quite close. Here's the Engine Analyzer Pro results, and my Engine Builder Professional results.
This is encouraging that my free software gets nearly the same result as a $500 software package with the identical engine specs.
I did finally find a guy in AZ that will line bore my Dart Iron Eagle block for 50 mm cam bearings, had no idea that was going to be so hard to find. Gary's Machine couldn't do it, Larry's Engine & Marine couldn't do it, no one could do it in Tucson, but Zimmerman Racing Engines in Phoenix can do it right at home! That guy really has his stuff together! yeah, it was quite a treat to see his machine shop in his back yard, awesome!
07-10-2017, 10:46 PM
. I think I can improvise a drill press vise to R&R rod bolts. Whatch'a think? Pretty sure that will get'm out but not sure if it can work to press the bolts back in.
. At least if they are ideas and not to sarcastic.
