Hi , I'm new here and I love reading this forum .
I'm refreshening an 540 CI engine that uses a DRCE block and with the pontiac (old prostock head ) . It has a 4 inch stroke and 4.626 bore .
I teared down the whole engine today and and I see the the main cap bolts are grade 8 bolts . Come these standart on the DRCE block ? I would had expected something like ARP studs . Well , this engine was running 7.30s in the 1/4 mile so it must be good . Do you guys know the torque specs for these bolts with moly lube ?
The customer wants to run in a class that needs to run single carb and auto transmition ( no lenco etc ) . I had to check for the cam specs myself cause we don't have any info on this engine . The duration at .050 is 300/308 , .510/.470 , 114.5 lobe sep (installed at 113.5 intake centerline ) . I might be off 1-3 degrees but it is close . It don't even have the 4-7 swap cam . It was an 2 carb , sheetmetal intake deal . Would this cam work on what we are planning or would you guys recomend something else ? Do you guys know what type of vave job works good on these pontiac head ? I was thinking on trying a 50 degree valve job cutter that I have on the intake and a 55 degree on the exhaust . Or do they use 55 on the intake too on these heads ? I'm gonna put it on the flowbench monday when i have the heads disambled and see what they flow now . Should I check it with higher presure like 30+ inches of water or the standart 28 inches of water should be fine ?
Thanx
DRCE block questions
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Hi,
If you can find the torque specs, and don't plan on line honing it I would just leave the bolts in there. If you can't find them or plan on cleaning up the main line, then I would put a stud in it. Then you know what the spec is. I wouldn't fiddle witha 50 or 55 degree angle on those unless it is already there. I don't think you'll be able to take advantage of those cuts unless you want to replace all of the seats in the heads along with all of the valves too. That can get pretty spendy. I would call a cam company you trust for a new design. If that cam was ground for a high rpm dual four motor and your not going to put that stuff back on there then there would be something better out there I would think.
Shawn
If you can find the torque specs, and don't plan on line honing it I would just leave the bolts in there. If you can't find them or plan on cleaning up the main line, then I would put a stud in it. Then you know what the spec is. I wouldn't fiddle witha 50 or 55 degree angle on those unless it is already there. I don't think you'll be able to take advantage of those cuts unless you want to replace all of the seats in the heads along with all of the valves too. That can get pretty spendy. I would call a cam company you trust for a new design. If that cam was ground for a high rpm dual four motor and your not going to put that stuff back on there then there would be something better out there I would think.
Shawn
Thanx for the replies . I checked on the web and I found torque specs for grade 8 bolts which is around 90 ft/lbs with moly . I am planning on using these bolts again . Everything looked good on the engine even the rod and main bearing looked like new . It was reving to 9300 rpm . One other thing , does the bolts that is in the lifter valley to hold the heads need to be torqued or just snugged ?
thanx
thanx
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bill jones
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-If you intend to reuse the rod bearings you need to know about and fix the "bearing crush".
--Take a new bearing out of the box and measure the width across the parting surface and compare that measurement to the distance across the parting surface of the rod or cap.
-You'll find the bearing is much wider---something like .040" or so---and you'll probably find the used bearing only having about .020" crush.
-So this means that you have to tug on the bearing shells with your thumbs and gently spread the bearing width back to near whatever the new bearing width is.
-If you fail to do this, there is good chances of inducing some sort of a rod bearing related failure.
---------------------------------------------
-As far as I know, I haven't found a way to get a torque wrench onto those valley bolts, in fact it's a bit of a problem to get a box end wrench down in there unless the block has been relieved for the wrench .
-Personally I use allen bolts and I use an allen wrench with an extended handle I made---about 14" long---and I pull this by hand pretty darn snug.
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-But I have torqued these bolts up to 70# in a fixture and then pulled the special allen wrench by hand until I "got the feel" that equaled that 70#.
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-If I was to continue to use the main bolts I would number them and keep them in the same holes----so that the male and the female threads continue stay happy with each other.
-There seems to be ongoing debates with conflicting ideas about what is best---bolts or studs---but in the end there doesn't seem to be any clear cut answer.
-I think that making sure you have plenty of engaged threads within the block is extremely important in either case, and that goes for head bolt hole and fastener threads for those positions.
-Aluminum BBC's need special attention to using every possible thread you can get within ALL the large bolt holes of the block.
-----------------------------------------------------
-I have seen only just a few of the big chief style engines and I am truly amazed at the excellent condition of the rod and main bearing even on 632's that run 8200rpm.
-I have seen the beginning of problems with the cambearings showing more wear than I like to see so I modify the cam bearings to incorporate a second oil hole at about the 4 oclock position and then I machine/scribe in a short narrow connecting slot on the outside of the cam bearing shells between those two oil holes.
--Take a new bearing out of the box and measure the width across the parting surface and compare that measurement to the distance across the parting surface of the rod or cap.
-You'll find the bearing is much wider---something like .040" or so---and you'll probably find the used bearing only having about .020" crush.
-So this means that you have to tug on the bearing shells with your thumbs and gently spread the bearing width back to near whatever the new bearing width is.
-If you fail to do this, there is good chances of inducing some sort of a rod bearing related failure.
---------------------------------------------
-As far as I know, I haven't found a way to get a torque wrench onto those valley bolts, in fact it's a bit of a problem to get a box end wrench down in there unless the block has been relieved for the wrench .
-Personally I use allen bolts and I use an allen wrench with an extended handle I made---about 14" long---and I pull this by hand pretty darn snug.
----------------------------------------------
-But I have torqued these bolts up to 70# in a fixture and then pulled the special allen wrench by hand until I "got the feel" that equaled that 70#.
--------------------------------------------
-If I was to continue to use the main bolts I would number them and keep them in the same holes----so that the male and the female threads continue stay happy with each other.
-There seems to be ongoing debates with conflicting ideas about what is best---bolts or studs---but in the end there doesn't seem to be any clear cut answer.
-I think that making sure you have plenty of engaged threads within the block is extremely important in either case, and that goes for head bolt hole and fastener threads for those positions.
-Aluminum BBC's need special attention to using every possible thread you can get within ALL the large bolt holes of the block.
-----------------------------------------------------
-I have seen only just a few of the big chief style engines and I am truly amazed at the excellent condition of the rod and main bearing even on 632's that run 8200rpm.
-I have seen the beginning of problems with the cambearings showing more wear than I like to see so I modify the cam bearings to incorporate a second oil hole at about the 4 oclock position and then I machine/scribe in a short narrow connecting slot on the outside of the cam bearing shells between those two oil holes.
Thats alot of information , thanx .
Most of the parts is gonna be new ( bearings , bme rods , piston , valve spring ,locks , etc ) .
There was a problem trying to use the cheap dialbore gauge (not sunnen ) to check the bearing clearance but it was giving some funny readings . It was showing .005 clearance which I'm sure it don't have that . The problem with these gauges is that it has a round cast around where the pin is and on small rod journals ( 2.0985 ) it was touching the cast instead of the pin . These are good to check bores etc .
I'm getting my sunnen gauge today so i could check the clearances . We are getting new pistons cause most of the pistons had a broken ringland right where they notched the piston for the intake valve which you can even see on the good ones that they all went thrue ( So i can see a little of the top ring ) . We send a good one to JE so they can duplicate all these pistons . I try to duplicate everything on this engine like clearances and parts as much as posible .
Thanx
GJ
Most of the parts is gonna be new ( bearings , bme rods , piston , valve spring ,locks , etc ) .
There was a problem trying to use the cheap dialbore gauge (not sunnen ) to check the bearing clearance but it was giving some funny readings . It was showing .005 clearance which I'm sure it don't have that . The problem with these gauges is that it has a round cast around where the pin is and on small rod journals ( 2.0985 ) it was touching the cast instead of the pin . These are good to check bores etc .
I'm getting my sunnen gauge today so i could check the clearances . We are getting new pistons cause most of the pistons had a broken ringland right where they notched the piston for the intake valve which you can even see on the good ones that they all went thrue ( So i can see a little of the top ring ) . We send a good one to JE so they can duplicate all these pistons . I try to duplicate everything on this engine like clearances and parts as much as posible .
Thanx
GJ
GJ - The key to getting to the inner head studs is to use the 3" long extentions that Snap-On sells that have 3/8" (or whatever size the torque wrench is) drive to boxed ends. There is a formula for the lesser amount of torque needed due to the extra leverage. On our inner head studs we recommend 45 - 50 ft.lb. but with the extra adaptor on we torque the studs to about 43 ft.lb. 
the cam you have now will not work in an automatic tranny application, especially one with a Glide. In fact, i cannot believe it ever worked, period. 300* @.050 is way too much intake duration no matter what the application is. I would rather see something in the mid 270 range with .900+ lift. If it needs to be low maintainence then you would have to add more duration and lower the lift. I think .800-.850" and 280 duration would be reliable and work well. I suspect that you could do a new set of pistons with less intake pocket depth and pick up some compression or take some dome away if you dont need any more compression...
Well , I was surprised too when i checked the duration . I am pretty sure I checked it right . I have those dial indicators that fit in the lifter bore from power house tool and I put a degree wheel and I start on the intake and I check when it is at .050 lift and I write down what the degree is and then I turn the engine over all past max lift and starts coming back down untill the dial indicator stops moving and go back around .060 and go to .050 lift to remove the slag and count it . Is this the right way ? And for the piston , JE called me when they recieved the good piston and they said they can make it exacly the same but they said it might brake the ringland again where it is thin so they said they can make the ring land thicker but then we might have to use oil ring spacer (it didn't need spacer before ) . This engine made @ 1200HP . Do you recomend any cam company to make a cam for me ? I was thinking on LSM but i'm not sure . The goal is to run high 7s with a glide and single carb . You have any idea how much power am I gonna lose going to single carb ? They were running a lenco when they ran 7.30s .
Thanx
Thanx
Last edited by GJ on Wed Oct 19, 2005 10:37 pm, edited 1 time in total.