Taking the dragster to the track tomorrow. Truck now runs on the new fuel system. Have a few leaks to work out, and re-plumb the venting system.
Another build thread + Racing Updates
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Whizzer
Gig'em
Really enjoy your rebuild on the Dakota and work on the dragster. What are your plans for the Dakota? Curious since I am a Mopar fan and had several Dakotas since 1987 when they first produced them.
Go fast enough to need a cage; keep the 1/4 mile under 135MPH to prevent needing a full cage. I have some tricks up my sleeve to do so. If I can run 10.70 @ 133 I'll be happy.
Welp, I'll let the photos tell the story on this one. We think that two 5/16 bolts came loose and caused all this; how two 5/16 bolts is stronger than four 3/8 bolts is beyond us. But with those 2 bolts coming out, it pulled all 4 rockers bolts right out of the head and broke the stand.
Ouch
Yep. No telling what this will cost. Last year we broke an exhaust and it damaged a whole bunch of things from hydraulicing the engine (fuel in with no exit). This time it was an intake, so other than the pool of oil sitting on top of the intake valve and 2 banged up rocker arms, no critical parts breakage.
Just have to get a new intake stand, 2 new rockers and have the head welded up and re-threaded where the bolts yanked the material out. Lifters and pushrods look okay.
Welp, I'll let the photos tell the story on this one. We think that two 5/16 bolts came loose and caused all this; how two 5/16 bolts is stronger than four 3/8 bolts is beyond us. But with those 2 bolts coming out, it pulled all 4 rockers bolts right out of the head and broke the stand.
Looks like the threads are on one of those bolts
What are the chances that bolt partially backed out?
Looks to me like it pulled out but its hard to say without actually looking close at it. The bolt that has pulled threads on it kind of looks a bit stretched as well but it could be distortion in the picture
yea that's distortion. The threads just pulled straight out on all 4.
I mean, those valvesprings are 400 pounds, there's 3 layers of spring material in there. We're asking for alot out of the valvetrain.
The general consensus is that TimeSerts are stronger than the aluminum and provide more gripping surface area and they are the standard repair for this issue, rather than welding and tapping.
I mean, those valvesprings are 400 pounds, there's 3 layers of spring material in there. We're asking for alot out of the valvetrain.
The general consensus is that TimeSerts are stronger than the aluminum and provide more gripping surface area and they are the standard repair for this issue, rather than welding and tapping.
No coil bind going on ? A good insert is much stronger, I have had very good luck, even with the old Heli- coil inserts in aluminum. I have used inserts in main cap threads with no issues
We run them .150-.200 short of coilbind
Dad took both heads to Reher-Morrison today. Since one side broke, they want to examine the other side. Going to put the time-serts in and weld up the mounting stands so that the intake and exhaust system is unified as one huge assembly...the way it should be.
Somethign to keep in mind in all of this... This is fairly new territory for conventional chevy engines. It used to be that for anything over 1500, everybody went to some variant of the Brad Anderson Engineering Hemi family (BAE3, 4, 5, 6, 7). As manufacturing processes have improved, now we have these blown alky conventional chevy engines approaching and/or surpassing 2,000 HP, Brad Hemi's going north of 5,000, and 481X (chevy bottom end, hemi top end hybrid engine) in the 4-5,000 range.
As such, material and design failures are going to happen. These parts and pieces are getting pushed WAYYYYY beyond the intended design and implementation. It's only a matter of time, and it costs money and time to magnaflux every part after every race/event/teardown. It would have been way cheaper if we had bought an older Brad3 or Brad5 hemi (essentially 5-8 year old Top Alcohol stuff) like others are doing. But my truck engine is the first chrysler dad's ever built, so we didn't want to build a hemi being completely blind and hope it made 2500-3000 HP first try.
As such, material and design failures are going to happen. These parts and pieces are getting pushed WAYYYYY beyond the intended design and implementation. It's only a matter of time, and it costs money and time to magnaflux every part after every race/event/teardown. It would have been way cheaper if we had bought an older Brad3 or Brad5 hemi (essentially 5-8 year old Top Alcohol stuff) like others are doing. But my truck engine is the first chrysler dad's ever built, so we didn't want to build a hemi being completely blind and hope it made 2500-3000 HP first try.
Reher was able to source a new intake stand, they think they'll have the heads welded and done tomorrow. Might be able to put them on Friday afternoon and head back to the track on Sunday.
Finished plumbing the fuel cell vent on the truck today, also got the bed bolted back on and replaced the fuel rail fitting with one I can trust.
Have a couple small drips off the AN fittings that I need to address, but what I have is progress regardless. Might be able to drive it to the gas station tomorrow.
Having changed the front brakes, front springs, and fuel system all at once, I have no idea what to expect for handling.
Finished plumbing the fuel cell vent on the truck today, also got the bed bolted back on and replaced the fuel rail fitting with one I can trust.
Have a couple small drips off the AN fittings that I need to address, but what I have is progress regardless. Might be able to drive it to the gas station tomorrow.
Having changed the front brakes, front springs, and fuel system all at once, I have no idea what to expect for handling.
Haven't had any time to work on the truck.
Have a ride from today. Having fuel issues, so only making 1/8-1000 runs.
Have a ride from today. Having fuel issues, so only making 1/8-1000 runs.
It's been a week. I did the math, I've worked over 100 hours in 6 days.
With 3 unrelated parts failures, it's amazing that we even made it to third round. We could have won that round, but one of the failures bit us hard.
With 3 unrelated parts failures, it's amazing that we even made it to third round. We could have won that round, but one of the failures bit us hard.
Nitro Dude
Hauler Driver and Cylinder Head Maintenance
The car sounds good Mag...
but please don't lay down in front of the rear tires when the car is running.
but please don't lay down in front of the rear tires when the car is running.
Yea dad tagged me on that, he didn't see my signal to hold. But I know the routine and was ready to get up if he put it in gear.The car sounds good Mag...
We had used up our 2 oil-down warnings in Q4 and E1. I wanted to make it a point that we weren't leaking "this time".
Been a while since last update. We started on the block last Sunday, starting with grinding and polishing the lifter valley to sterilize it and improve oil drainback. I roughed it in for 2 hours, then dad went in and did all the finesse for another 2 hours. Then today I went through and tapped every thread in the block 3 times each, before we pulled the main girdle and caps off, tapped out those threads, then dad started polishing the main caps.
Next up is to start scrubbing and cleaning all the varnish and dirt from the block, hone out all the surfaces, brush it again, then run a strong acid concentrate through the entire block (basically a pressure washer acid bath) to do a final cleaning.
Next up is to start scrubbing and cleaning all the varnish and dirt from the block, hone out all the surfaces, brush it again, then run a strong acid concentrate through the entire block (basically a pressure washer acid bath) to do a final cleaning.
When you get finished, you can come do my windows.
Looks beautiful.
Looks beautiful.
Went back out after dinner and put another 2 hours in with the wire wheel and hand brush.
Spent all morning putting in another 10 man-hours of work to clean and prep the block, then painted it. About to head to Summit to get more parts.
https://lh3.googleusercontent.com/oJv-FDonDU5ZwculiDkeZ5kYwj57YMpzRI8hzOj-r3Ow3VtlK-2eiJ4cKF0xvJ6jawojST2DK2A1kyDfKUPPm0_X3KzixxZCverAUAXtYc5UwluHgMCzLTMQs943metJIt7gDsZ8mc4WWKdrJOUNISMih0GLtUL3kPe9EQXd41h676h4SClf5ZPcKR6Dz5kBta21hA0pnQSsoPzt_TpX_FurG07QckL2zFtjNhRcOSAUz_OSXAgqW3LMoiaBSWPGnXx1pmYA0bJDtRkyKgQ3-P1_4q_0AExZ79lSauI5IOnSqgkpBG0vJlXt_cW5F2r52S3uqeAPc34jNdx643IVge0DpCj5PB_Pm****onO0L3htVibIC8w3h4OK3f7BZ2KF17p5yIseoqYOaRE3FMNY_yYTqxryAihDQJCHeEW_DYBZplJtFfJggll2PpLzC6_E8BmvUHb76hCAGjxr86b99ty2AGT5GpXINU-9fVWx-Avg0lARiAVUx64XE723w_bgvLppfbR4K7Bnka1wNfatwBRTpBxAxuHGIzBDS7SY33FUiL618A8cANqdmkfF5u__fbV5xziaCYQAilWvqCk-UG-Gq6pGBjEIb9vzbA5CVbrpdfmgAg9gvoeLh8hQwU1tHDGSjZVHKr_uqvVc7YsviLjShNM6Xs=w490-h871-no
https://lh3.googleusercontent.com/oJv-FDonDU5ZwculiDkeZ5kYwj57YMpzRI8hzOj-r3Ow3VtlK-2eiJ4cKF0xvJ6jawojST2DK2A1kyDfKUPPm0_X3KzixxZCverAUAXtYc5UwluHgMCzLTMQs943metJIt7gDsZ8mc4WWKdrJOUNISMih0GLtUL3kPe9EQXd41h676h4SClf5ZPcKR6Dz5kBta21hA0pnQSsoPzt_TpX_FurG07QckL2zFtjNhRcOSAUz_OSXAgqW3LMoiaBSWPGnXx1pmYA0bJDtRkyKgQ3-P1_4q_0AExZ79lSauI5IOnSqgkpBG0vJlXt_cW5F2r52S3uqeAPc34jNdx643IVge0DpCj5PB_Pm****onO0L3htVibIC8w3h4OK3f7BZ2KF17p5yIseoqYOaRE3FMNY_yYTqxryAihDQJCHeEW_DYBZplJtFfJggll2PpLzC6_E8BmvUHb76hCAGjxr86b99ty2AGT5GpXINU-9fVWx-Avg0lARiAVUx64XE723w_bgvLppfbR4K7Bnka1wNfatwBRTpBxAxuHGIzBDS7SY33FUiL618A8cANqdmkfF5u__fbV5xziaCYQAilWvqCk-UG-Gq6pGBjEIb9vzbA5CVbrpdfmgAg9gvoeLh8hQwU1tHDGSjZVHKr_uqvVc7YsviLjShNM6Xs=w490-h871-no
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It's looking good. A lot of hard work involved.Spent all morning putting in another 10 man-hours of work to clean and prep the block, then painted it. About to head to Summit to get more parts.
https://lh3.googleusercontent.com/oJv-FDonDU5ZwculiDkeZ5kYwj57YMpzRI8hzOj-r3Ow3VtlK-2eiJ4cKF0xvJ6jawojST2DK2A1kyDfKUPPm0_X3KzixxZCverAUAXtYc5UwluHgMCzLTMQs943metJIt7gDsZ8mc4WWKdrJOUNISMih0GLtUL3kPe9EQXd41h676h4SClf5ZPcKR6Dz5kBta21hA0pnQSsoPzt_TpX_FurG07QckL2zFtjNhRcOSAUz_OSXAgqW3LMoiaBSWPGnXx1pmYA0bJDtRkyKgQ3-P1_4q_0AExZ79lSauI5IOnSqgkpBG0vJlXt_cW5F2r52S3uqeAPc34jNdx643IVge0DpCj5PB_Pm****onO0L3htVibIC8w3h4OK3f7BZ2KF17p5yIseoqYOaRE3FMNY_yYTqxryAihDQJCHeEW_DYBZplJtFfJggll2PpLzC6_E8BmvUHb76hCAGjxr86b99ty2AGT5GpXINU-9fVWx-Avg0lARiAVUx64XE723w_bgvLppfbR4K7Bnka1wNfatwBRTpBxAxuHGIzBDS7SY33FUiL618A8cANqdmkfF5u__fbV5xziaCYQAilWvqCk-UG-Gq6pGBjEIb9vzbA5CVbrpdfmgAg9gvoeLh8hQwU1tHDGSjZVHKr_uqvVc7YsviLjShNM6Xs=w490-h871-no
Ooooo, I love shiny new things --- especially when they go fast.
Well, I was hoping tonight's report would be that the crank was laid in and final.
It is not so, and I am making the 5-hour-each-way trip to Houston in the morning.
Main bearing clearance is way wide. Stock is .0010 to .0015. Race is .0030 to .0035. We are shooting for .0020 to .0025.
The two methods of instrumentation that we have are showing .0050 to .0060. No bueno.
It is not so, and I am making the 5-hour-each-way trip to Houston in the morning.
Main bearing clearance is way wide. Stock is .0010 to .0015. Race is .0030 to .0035. We are shooting for .0020 to .0025.
The two methods of instrumentation that we have are showing .0050 to .0060. No bueno.
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Damn. Good luck.
Mag sent me a pic of the conversation he had with the tech who did the job. Tech didn't seem to care that the
measurements were that far off. Basically, he shrugged it off.
Cannot believe it was that far off what it was supposed to be. Somebody really screwed up.
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Yep. Maybe one too many ****tails at lunch.
So here's an update: I drove for 9 hours today and was at the machine shop for an hour and a half. The good news: I came home with the block.
Here is the jist of it: $2,000 tools and $200 tools have different levels of accuracy.
Our dial bore gauge is "cheap" and accurate to half a thousanth (.0005) and is not exactly calibrated except by mic.
The machine shop's dial bore gauge is "not cheap" and accurate to half a ten-thousandth (.00005) and calibrated before every measurement.
The spec for the main bore is 3.0025 to 3.0030. Measurement is 3.0029 to 3.0032.
The spec for the crank is 2.8095 to 2.8105. Measurement is 2.8093.
Zeroing the dial bore indicator to 2.8093, we came up with 0.0033 to 0.0039 across the mains.
The difference between those is 0.1936 to 0.1939. The bearing spec's out maximum wall of 0.0953, or 0.1906 total.
0.1936 - 0.1906 = 0.0030
0.1939 - 0.1906 = 0.0033
Add in some of the bearings maybe being a hair thin, and the numbers we measured make sense.
The machinist and I discussed it, and we concurred that everything is in good shape all things considered. (elaborate later). I called Eddie Miller, he also agreed that those numbers are good all things considered. I called Hughes Engines, and they also concurred that those numbers, while a tad wider than they'd like, are in good shape all things considered.
"All things considered"
The small block chryslers are known to be inherently weak in the bottom end. The block design is from the 1960's (literally - same general block casting for 273/318/340/360 from the 60's to the 2000's, give to take some minor changes in 1989 and again in 1997). Hence running a girdle to tie the bottom end all together. Because of how the block is known to deflect, running a little extra clearance than would otherwise be run is not a bad thing.
Eddie Miller did bring up a good point that I will need to check the bearing crush. 2 ten-thou out of spec should not hurt anything, but merely being towards the high spec can reduce the crush just enough that it may want to spin the bearing. The 'locator tang' is just that - a locator tang. It never was intended to prevent the bearing from turning in the housing bore. He pointed out that many newer engines do not feature this tang at all, the bearings use only the crush value to hold it in the block and cap without turning.
Here is the jist of it: $2,000 tools and $200 tools have different levels of accuracy.
Our dial bore gauge is "cheap" and accurate to half a thousanth (.0005) and is not exactly calibrated except by mic.
The machine shop's dial bore gauge is "not cheap" and accurate to half a ten-thousandth (.00005) and calibrated before every measurement.
The spec for the main bore is 3.0025 to 3.0030. Measurement is 3.0029 to 3.0032.
The spec for the crank is 2.8095 to 2.8105. Measurement is 2.8093.
Zeroing the dial bore indicator to 2.8093, we came up with 0.0033 to 0.0039 across the mains.
The difference between those is 0.1936 to 0.1939. The bearing spec's out maximum wall of 0.0953, or 0.1906 total.
0.1936 - 0.1906 = 0.0030
0.1939 - 0.1906 = 0.0033
Add in some of the bearings maybe being a hair thin, and the numbers we measured make sense.
The machinist and I discussed it, and we concurred that everything is in good shape all things considered. (elaborate later). I called Eddie Miller, he also agreed that those numbers are good all things considered. I called Hughes Engines, and they also concurred that those numbers, while a tad wider than they'd like, are in good shape all things considered.
"All things considered"
The small block chryslers are known to be inherently weak in the bottom end. The block design is from the 1960's (literally - same general block casting for 273/318/340/360 from the 60's to the 2000's, give to take some minor changes in 1989 and again in 1997). Hence running a girdle to tie the bottom end all together. Because of how the block is known to deflect, running a little extra clearance than would otherwise be run is not a bad thing.
Eddie Miller did bring up a good point that I will need to check the bearing crush. 2 ten-thou out of spec should not hurt anything, but merely being towards the high spec can reduce the crush just enough that it may want to spin the bearing. The 'locator tang' is just that - a locator tang. It never was intended to prevent the bearing from turning in the housing bore. He pointed out that many newer engines do not feature this tang at all, the bearings use only the crush value to hold it in the block and cap without turning.
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Damn, and I used to worry about getting the plugs gapped right and the timing set correctly.
We re-measured tonight. Mic comes up with 2.8095 on the crank to shop's 2.8093, so close enough for what we're doing.
3.9/4.5
3.3/4.1
3.8/4.5
3.5/4.0
3.1/3.5
We're showing 0.4 to 0.8 wider than the machine shop.
3.9/4.5
3.3/4.1
3.8/4.5
3.5/4.0
3.1/3.5
We're showing 0.4 to 0.8 wider than the machine shop.
There's alot of things that go on that very few ever know about. You can't see 5 one-hundred-thousandths of an inch (0.00005), but the dial bore gauge can. Stack 20 of those together and you have an oiling problem.
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I knew that it was going on but it was well above my knowledge level. At least I realized it and took it to the right people that knew what they were doing, unlike some of my friends back then.
Took a trip over to Reher-Morrison to get a third opinion on bearing clearances. Original machinist is #1, ours is #2, RM is #3.
While at RM, we checked each main on the crank twice and averaged the two values. We came up with 2.80915 to 2.80950, 3.5 ten-thou variance across the mains.
Front main #1: .0039
Front main #2: .0045
Front main #3: .0035
#2 main #1: .0033
#2 main #2: .0041
#2 main #3: .0040
Thrust main #1: .0038
Thrust main #2: .0045
Thrust main #3: .0041
#4 main #1: .0035
#4 main #2: .0040
#4 main #3: .0032
Rear main #1: .0031
Rear main #2: .0035
Rear main #3: .0031
While at RM, we checked each main on the crank twice and averaged the two values. We came up with 2.80915 to 2.80950, 3.5 ten-thou variance across the mains.
Front main #1: .0039
Front main #2: .0045
Front main #3: .0035
#2 main #1: .0033
#2 main #2: .0041
#2 main #3: .0040
Thrust main #1: .0038
Thrust main #2: .0045
Thrust main #3: .0041
#4 main #1: .0035
#4 main #2: .0040
#4 main #3: .0032
Rear main #1: .0031
Rear main #2: .0035
Rear main #3: .0031
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We have always built race motors at .0030 to .0035. Anything after .0035 is considered excessive. The rear main is good regardless. The other 4 simply depend on which number you want to trust.
They are okay to run wide, but I'll lose oil pressure since there is a bigger volume to fill. Running a high-volume oil pump makes up for that a little, but it takes more horsepower to turn and puts a bigger load on the oil pump driveshaft (which is only 5/16" hex bar on a chrysler). An HV pump also has potential to suck the pan dry if the oil can't return from the top of the engine fast enough. That goes back to polishing the lifter valley and the return troughs on the cylinder heads. Insurance to that is running a bigger pan, which requires me to do some cutting and welding on the K-member to clear the bigger oil pan.
Welcome to Dominoes: Engine building edition
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I understood that perfectly after one reading. Thanks. I guess that I'm still a gearhead.
got the cam and crankshaft laid in. crankshaft thrust is good at 6 thou.
started re-checking rod bearings and they are showing 1-1.5 all the way across. that's too tight. So I have to get another set that are machined thinner to give more clearance. 481-HNK out, 481-HXNK in.
started re-checking rod bearings and they are showing 1-1.5 all the way across. that's too tight. So I have to get another set that are machined thinner to give more clearance. 481-HNK out, 481-HXNK in.
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