Build Thread - 85 IROC 402 LS3 6 speed
#101
Re: Build Thread - 85 IROC 402 LS3 6 speed
Minor update: Last night I cut a couple grooves into one of my old cylinder head bolts and used it to clean the head bolt threads. After I finished that, I started to install the wrist pin retainers into the pistons. This is the first time I've had the pleasure of using these things... man, what a pain in the ***. I've got 2 pistons done so far.
I also discovered that I made a mistake when I was tightening my main cap bolts. I tightened to 15 ftlbs, then another 80* of rotation for both sets of bolts. I see now that the outer set should only be torqued 51 degrees. Good thing I used the old bolts for mock-up!
I also discovered that I made a mistake when I was tightening my main cap bolts. I tightened to 15 ftlbs, then another 80* of rotation for both sets of bolts. I see now that the outer set should only be torqued 51 degrees. Good thing I used the old bolts for mock-up!
#105
Re: Build Thread - 85 IROC 402 LS3 6 speed
Last night I installed the wrist pin retainers on the remaining 6 pistons. On the first piston I did last week, it took me 20 minutes or more to install the two retainers. On the last piston, I think it took me 20 seconds.
By the time I got to piston number 6, I wasn't even using a tool anymore, I just did it completely by hand. It's funny how you get good at these things just as you're finishing up.
Tonight I'm hoping to have Dad come up so he can hold the crank while I clean it up, then I can do my final assembly on the short block.
By the time I got to piston number 6, I wasn't even using a tool anymore, I just did it completely by hand. It's funny how you get good at these things just as you're finishing up.
Tonight I'm hoping to have Dad come up so he can hold the crank while I clean it up, then I can do my final assembly on the short block.
#106
Re: Build Thread - 85 IROC 402 LS3 6 speed
Last night I cleaned the block and crank, slapped a pile of assembly lube onto the bearings and journals, and installed the main caps, hopefully for the last time.
one frustrating thing that I ran into is my crank endplay... again. I had .004" when I installed with oil, but now with the assembly lube, I can barely get .002" when I reef on it with a screwdriver. Same bearings, same everything. The crank spins freely (or as freely as it can spin now that it's in a bath of assembly lube).
Has anybody else had a similar situation, where the liberal use of assembly lube prevented an accurate endplay measurement?
one frustrating thing that I ran into is my crank endplay... again. I had .004" when I installed with oil, but now with the assembly lube, I can barely get .002" when I reef on it with a screwdriver. Same bearings, same everything. The crank spins freely (or as freely as it can spin now that it's in a bath of assembly lube).
Has anybody else had a similar situation, where the liberal use of assembly lube prevented an accurate endplay measurement?
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Re: Build Thread - 85 IROC 402 LS3 6 speed
Jim I have been following this thread for a while now without being and idiot responder. Do you have any experience in building an engine before this? I am debating rebuilding the BBC in my 73 or buying another and doing that one
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Re: Build Thread - 85 IROC 402 LS3 6 speed
I'll have to say subscribed to this as well. Some incredible attention to detail with very few "aw screw its". As long as you get those valve springs to come out right you should be able to rev the crap outta this thing.
#113
Re: Build Thread - 85 IROC 402 LS3 6 speed
Looks good, keep it up, nice, any updates?
Jim I have been following this thread for a while now without being and idiot responder. Do you have any experience in building an engine before this? I am debating rebuilding the BBC in my 73 or buying another and doing that one
Jim I have been following this thread for a while now without being and idiot responder. Do you have any experience in building an engine before this? I am debating rebuilding the BBC in my 73 or buying another and doing that one
Originally Posted by White'89
I'll have to say subscribed to this as well. Some incredible attention to detail with very few "aw screw its". As long as you get those valve springs to come out right you should be able to rev the crap outta this thing.
By the way guys, no progress lately. Been busy with other crap. I hope that tomorrow I'll get time to pull the crank out yet again so I can wipe off the assembly lube and re-convince myself that I have the endplay clearance that I need.
#114
Re: Build Thread - 85 IROC 402 LS3 6 speed
Last night I pulled the main caps back off the block. After I did, the crank had about 4 to 4.5 thousands of endplay. I re-assembled the main caps, this time smacking the crank back and forth with just the #3 cap in place (and tightened to less than the 15ftlbs it was tightened to last time), and things seemed to go much better. After fully torquing all of the caps, I still had my 4 thousands of endplay.
I'm much happier now.
I'm much happier now.
#119
Re: Build Thread - 85 IROC 402 LS3 6 speed
Nope. Life is getting in the way. Once it turned cold I stopped working in the garage for the winter, and then in March I started a speaker project that won't go away... those still aren't done, and now I'm knee deep in a summer-long bathroom remodel project.
Finding time to work on this motor is hopeless. Plus, I still haven't found anybody to buy my C4 for 1/2 of book value, so I still don't have any money for a trans & rear end, so my motivation to finish the motor isn't exactly all that high.
But... next weekend my buddy is coming to town, and we always enjoy turning wrenches together, so I'm planning to finally pull the plastic off the motor and work on it some more. Hoping to get the pistons & rods into the block. Then I'll basically just be a camshaft shy of being able to finish the long block.
Finding time to work on this motor is hopeless. Plus, I still haven't found anybody to buy my C4 for 1/2 of book value, so I still don't have any money for a trans & rear end, so my motivation to finish the motor isn't exactly all that high.
But... next weekend my buddy is coming to town, and we always enjoy turning wrenches together, so I'm planning to finally pull the plastic off the motor and work on it some more. Hoping to get the pistons & rods into the block. Then I'll basically just be a camshaft shy of being able to finish the long block.
#120
Re: Build Thread - 85 IROC 402 LS3 6 speed
Well, this weekend we put the rings on the pistons and dropped the rods & pistons into the block. I ran into some concern when measuring the rod bolt stretch. The card that came with the rods specified .005" of stretch, or 75 ft-lbs if you can't measure stretch. My concern was that at 75 ft-lbs, I only had .004" of stretch on the first bolt. Going up to 85 ft-lb made no difference, and I was afraid to go much tighter. I tightened all 16 bolts to 85 and only 3 reached .500". I called ARP and they didn't offer much except to say that stretch is the preferred method, and that I should call the rod manufacturer, so that's what I did. I called Callies and talked to their tech. He agreed that torquing the hell out of the bolts to get the .005" stretch didn't seem like a good idea, and ultimately suggested that I stick with my 85 ft-lb tightening.
So, at least I have some progress! There is a guy interested in my corvette too, so with any luck, I'll have the cash to move forward with the project again soon.
Here are a few pics of my bottom end:
So, at least I have some progress! There is a guy interested in my corvette too, so with any luck, I'll have the cash to move forward with the project again soon.
Here are a few pics of my bottom end:
Last edited by Jim85IROC; 08-08-2011 at 09:43 PM.
#124
Re: Build Thread - 85 IROC 402 LS3 6 speed
The guy that's hosting it has it on some POS computer that goes down more than a $20 transvestite. It's been down so much lately that I think most if not all of the forum members have moved on. I'm contemplating moving it to a more reliable site (that I'd have to pay for), but frankly, that site really didn't have much to offer that TGO doesn't have too.
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Re: Build Thread - 85 IROC 402 LS3 6 speed
Love all the attention to detail. Good job on doing it the right way.
#127
Re: Build Thread - 85 IROC 402 LS3 6 speed
Well, the Corvette sold today. It hurt to watch the guy drive off with it. But, at least it means that now I have the money to move forward with the project. I guess that I should decide which trans to go with. I'm considering a rebuilt t56 or a Magnum t56.
#128
Re: Build Thread - 85 IROC 402 LS3 6 speed
A coworker offered to let me borrow his spring compressor, and since I still hadn't perfected my DIY version, I took him up on his offer. Unlike the one my father has, this one was rigid enough to actually do its job with these springs, so I was able to re assemble the heads with my PRC springs.
Here's a pic of the spring compressor holding one of the springs down:
The first head went quickly, but on the 2nd head, the first intake valve I got to was a bastard. With the tool adjusted the same as on the other head, I couldn't compress the spring quite enough, and if I went to the next notch on the tool, it compressed it too much. I had to shim the tool to do the intake valves:
Here's one of the heads all done:
Here's a pic of the spring compressor holding one of the springs down:
The first head went quickly, but on the 2nd head, the first intake valve I got to was a bastard. With the tool adjusted the same as on the other head, I couldn't compress the spring quite enough, and if I went to the next notch on the tool, it compressed it too much. I had to shim the tool to do the intake valves:
Here's one of the heads all done:
#129
Re: Build Thread - 85 IROC 402 LS3 6 speed
Here's a bit of an update. Over the last few weeks I've ordered up almost all of the stuff I need to finish the motor. One of the only things that I'm lacking now is the cam. Choosing a cam for an LS3-headed motor is way more complicated than it should be. There are 2 camps out there, the camp that likes split duration cams with a bunch of exhaust duration, and those that like more intake and less exhaust. Decisions decisions...
But, in the meantime, at least I made some progress. Part of my bag of new parts included 8 new intake rockers and the Comp trunion kit.
Sorry for the poor picture quality. I forgot my camera so I had to use my phone.
First I started by pressing out the factory trunions:
Next, you press the new bearing into one side:
All pressed in:
Then you turn the rocker over, put the trunion in, stand it on a washer, and press the 2nd bearing into place, with another washer to provide clearance for the trunion:
Trunion & bearings installed:
Install the snap rings, rinse and repeat 15 more times.
But, in the meantime, at least I made some progress. Part of my bag of new parts included 8 new intake rockers and the Comp trunion kit.
Sorry for the poor picture quality. I forgot my camera so I had to use my phone.
First I started by pressing out the factory trunions:
Next, you press the new bearing into one side:
All pressed in:
Then you turn the rocker over, put the trunion in, stand it on a washer, and press the 2nd bearing into place, with another washer to provide clearance for the trunion:
Trunion & bearings installed:
Install the snap rings, rinse and repeat 15 more times.
#132
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Re: Build Thread - 85 IROC 402 LS3 6 speed
Looking good Jimbo!
I second the trunion upgrade kit. Cant beat the peace of mind/price ratio.
I second the trunion upgrade kit. Cant beat the peace of mind/price ratio.
#133
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Re: Build Thread - 85 IROC 402 LS3 6 speed
Awsome build thread and Ive learned alot more now. After reading this I will be doing the trunion mod as well to my stock rockers. Keep up the awsome work and look forward to more updates
#134
Re: Build Thread - 85 IROC 402 LS3 6 speed
Well... I FINALLY ordered my cam.
I talked to Don at Slowhawk, which is who will be doing my dyno tuning. He's the one that's going to determine my timing and fueling events, it makes sense to let him decide my valve events too.
Wound up with a 228/232 on a 115 lsa. Lift is a little lower than I'd figured (around .610) because he prefers a little bit less aggressive cam lobe in order to help keep the valves and seats alive. Peak horsepower might not get to the magical 500 RW number that I'd hoped, but I'm willing to trade good fat torque and excellent driveability for a few peak hp.
Once it gets here I can finally finish the motor.
I talked to Don at Slowhawk, which is who will be doing my dyno tuning. He's the one that's going to determine my timing and fueling events, it makes sense to let him decide my valve events too.
Wound up with a 228/232 on a 115 lsa. Lift is a little lower than I'd figured (around .610) because he prefers a little bit less aggressive cam lobe in order to help keep the valves and seats alive. Peak horsepower might not get to the magical 500 RW number that I'd hoped, but I'm willing to trade good fat torque and excellent driveability for a few peak hp.
Once it gets here I can finally finish the motor.
#136
Re: Build Thread - 85 IROC 402 LS3 6 speed
Ls3 heads don't respond to bigger cams. The intake valve is massive, so it needs way less cam than cathedral heads. Any more duration and you start getting too much overlap, which kills power because of reversion issues. This combo should get me at or near 500rwhp with stock drivability.
#137
Re: Build Thread - 85 IROC 402 LS3 6 speed
Cam is here. Specs are slightly different than what I was expecting. 227/231 613/617 114+3 The lobes are Comp LSL lobes
I suppose now would be a good time to order a degree wheel.
EDIT: Degree wheel ordered.
I suppose now would be a good time to order a degree wheel.
EDIT: Degree wheel ordered.
Last edited by Jim85IROC; 10-04-2011 at 08:44 PM.
#138
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Re: Build Thread - 85 IROC 402 LS3 6 speed
LSL lobes ftw with LS3 heads
Very similar cam to what Im running actually and I spent considerable time choosing as well. Mind you Im only hoping for 450 whp and considering anything above that a bonus but Im also only at 378 cubes so giving up a good bit there.
Very similar cam to what Im running actually and I spent considerable time choosing as well. Mind you Im only hoping for 450 whp and considering anything above that a bonus but Im also only at 378 cubes so giving up a good bit there.
#139
Re: Build Thread - 85 IROC 402 LS3 6 speed
The guy doing my tune (who also helped me choose a cam) said similar combos to mine have made 525hp/500tq on his Mustang dyno. We'll see. That sounds optimistic to me, especially the torque. My goal is 500rwhp with stock-like driveability.
#141
Re: Build Thread - 85 IROC 402 LS3 6 speed
Started my cam installation tonight.
Here's a pic of the cam:
A word of advice. Clean the inside of the cam! I looked inside and it was nasty. This was the crap that came out of it:
Prior to the installation, I also installed the seals into the front and rear covers.
Here's the rear cover without the seal. Notice that the stock seal also comes with an aligning tool:
To install the seal, GM sells some specialty tools. I happened to have some of my own:
They worked great!
Front cover without the seal:
Front cover with the seal:
Here's a picture of the cam almost home:
continued next thread...
Here's a pic of the cam:
A word of advice. Clean the inside of the cam! I looked inside and it was nasty. This was the crap that came out of it:
Prior to the installation, I also installed the seals into the front and rear covers.
Here's the rear cover without the seal. Notice that the stock seal also comes with an aligning tool:
To install the seal, GM sells some specialty tools. I happened to have some of my own:
They worked great!
Front cover without the seal:
Front cover with the seal:
Here's a picture of the cam almost home:
continued next thread...
#142
Re: Build Thread - 85 IROC 402 LS3 6 speed
Continued from last thread...
For those doing a build, the original style cam retainer plate was discontinued. The replacement part does NOT use the same bolts, so make sure you buy those too! Here's a pic of the two plates side to side. The new one is the one on the right with the flush-mount torx bolts. These new bolts only tighten to 11ft/lbs instead of the 18 that the old style torque to:
Cam plate installed:
Now everybody gets to hear about my boneheaded move. I pushed the crank gear onto the shaft, tapped it on, then drove it home with the harmonic balancer bolt, using the old gear acting as a spacer. I couldn't get it quite flush to the crank. I got a bigger ratchet. Twist, twist, POW! Things got all loose. I pulled it back apart, and discovered this:
It turns out, I'm a dummy. I installed the gear backwards, with the teeth facing AWAY from the block instead of toward it. The chamfer on the crank resulted in a split gear once I applied a bunch of torque. Dumb, dumb, dumb.
So, the cam installation sits until I can order a new gear from the dealer. :-/
For those doing a build, the original style cam retainer plate was discontinued. The replacement part does NOT use the same bolts, so make sure you buy those too! Here's a pic of the two plates side to side. The new one is the one on the right with the flush-mount torx bolts. These new bolts only tighten to 11ft/lbs instead of the 18 that the old style torque to:
Cam plate installed:
Now everybody gets to hear about my boneheaded move. I pushed the crank gear onto the shaft, tapped it on, then drove it home with the harmonic balancer bolt, using the old gear acting as a spacer. I couldn't get it quite flush to the crank. I got a bigger ratchet. Twist, twist, POW! Things got all loose. I pulled it back apart, and discovered this:
It turns out, I'm a dummy. I installed the gear backwards, with the teeth facing AWAY from the block instead of toward it. The chamfer on the crank resulted in a split gear once I applied a bunch of torque. Dumb, dumb, dumb.
So, the cam installation sits until I can order a new gear from the dealer. :-/
#143
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Re: Build Thread - 85 IROC 402 LS3 6 speed
In looking for cams, GMHTP did a nice cam only upgrade on an LS3 and was rewarded with 46X RWHP. I think it was a 228/242 629/620 112. In the book it was stating that the LS3 heads need alot more exhaust duration due to the port differances. Now I'm all confused as I was thinking of maybe doing another H/C package in the future. I'm running a 228/230 585/585 112 cam now and it seems like a baby on my motor.
#144
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Re: Build Thread - 85 IROC 402 LS3 6 speed
Let me be the next to say subscribed! Good thread and love the pics. Makes me wish I stored money to build my block
#145
Re: Build Thread - 85 IROC 402 LS3 6 speed
In looking for cams, GMHTP did a nice cam only upgrade on an LS3 and was rewarded with 46X RWHP. I think it was a 228/242 629/620 112. In the book it was stating that the LS3 heads need alot more exhaust duration due to the port differances. Now I'm all confused as I was thinking of maybe doing another H/C package in the future. I'm running a 228/230 585/585 112 cam now and it seems like a baby on my motor.
Just got off the phone with the dealership to order the new crank sprocket. Order had to be in by 3:30. I called immediately after the order was finalized. :-/ Fortunately, it'll still be here on Thursday.
#146
Re: Build Thread - 85 IROC 402 LS3 6 speed
Sort of an update. I took the car to Dyno Day at Slowhawk Performance in Bridgewater MA today. He'll be doing my tune after I put the new motor in, so I thought it would be great to get a "before" number with the current motor. As a refresher, the current motor is a .030 over 350 with forged flat top slugs, stock crank & rods, 461 fuelie heads (terrible heads for TPI), accel base, SLP runners, 24lb injectors, headers, 3" exhaust, and a 214/224 flat tappet cam. Car has a T5 and a 10 bolt.
The car put down 251hp on the first run, and 249 on the 2nd run, along with 331ftlbs of torque. These were rear-wheel numbers on a Mustang dyno. The car did better than I expected.
Here's a video of the run:
http://www.youtube.com/watch?v=Nzsw5BeVxLs
The car put down 251hp on the first run, and 249 on the 2nd run, along with 331ftlbs of torque. These were rear-wheel numbers on a Mustang dyno. The car did better than I expected.
Here's a video of the run:
http://www.youtube.com/watch?v=Nzsw5BeVxLs
#147
Re: Build Thread - 85 IROC 402 LS3 6 speed
Tonight I did a little bit of work, along with some educational disassembly.
First, the work. I installed the new crank gear, then the cam gear & chain. I discovered that the bolts that came with the timing gear set were too long and bottomed out in the Comp cam, so I reused the stock bolts, and tightened to 24ftlbs.
The next step is to install the oil pump. Based on a lot of advice on 'tech, I bought an "LS6" pump. I also have my stock LQ9 pump, and another used pump of unknown origin that I believe was also said to have been an LS6 pump.
Here are the three of them. My LQ9 pump is on the bottom, the unknown pump in the middle, and my new LS6 pump on the top:
The back. The two old pumps are made in Canada, the new one in Mexico:
I decided to take apart the old one:
Gears out:
Here's the crank gear installed to show how the pump works. As the crank gear turns, it squeezes the two gears together, which pushes the oil into the area under the gears, out the hole and into the block:
Continued next post (when the hell did TGO go down to an 8 image limit???)
First, the work. I installed the new crank gear, then the cam gear & chain. I discovered that the bolts that came with the timing gear set were too long and bottomed out in the Comp cam, so I reused the stock bolts, and tightened to 24ftlbs.
The next step is to install the oil pump. Based on a lot of advice on 'tech, I bought an "LS6" pump. I also have my stock LQ9 pump, and another used pump of unknown origin that I believe was also said to have been an LS6 pump.
Here are the three of them. My LQ9 pump is on the bottom, the unknown pump in the middle, and my new LS6 pump on the top:
The back. The two old pumps are made in Canada, the new one in Mexico:
I decided to take apart the old one:
Gears out:
Here's the crank gear installed to show how the pump works. As the crank gear turns, it squeezes the two gears together, which pushes the oil into the area under the gears, out the hole and into the block:
Continued next post (when the hell did TGO go down to an 8 image limit???)
#148
Re: Build Thread - 85 IROC 402 LS3 6 speed
continued..
Here's all 3 taken apart:
Here's the outlet on the new LS6 pump:
And here's the outlet on the old, unknown pump:
Of the 3, the new LS6 pump housing looks the worst. The machine work on the outlet hole is crap, and the casting is rough. Right now I'm a bit undecided on what to do. I don't know if I want to just run the new pump as is, port the new pump, or run the unknown or original pump as is. Honestly, both of the old pumps look perfect inside, and both are better made than the new LS6 pump.
Here's all 3 taken apart:
Here's the outlet on the new LS6 pump:
And here's the outlet on the old, unknown pump:
Of the 3, the new LS6 pump housing looks the worst. The machine work on the outlet hole is crap, and the casting is rough. Right now I'm a bit undecided on what to do. I don't know if I want to just run the new pump as is, port the new pump, or run the unknown or original pump as is. Honestly, both of the old pumps look perfect inside, and both are better made than the new LS6 pump.
#149
Re: Build Thread - 85 IROC 402 LS3 6 speed
If you reuse an old pump, be sure to pop the bypass valve out and clean the cyl extensively so movement is fluid. With gerator pumps, failure usually isnt by the pump, but instead a stock valve bypassing too much oil so the system cannot maintain adequate pressure. This starves bearings and ruins your day
You can try porting the pump, which essentially is knocking the sharp edges off the inlet and shaping the round outlet hole into a smoothed funnel shape. Shimming the bypass valve spring with a small washer or nut wont hurt to build a few more pounds of pressure
You can try porting the pump, which essentially is knocking the sharp edges off the inlet and shaping the round outlet hole into a smoothed funnel shape. Shimming the bypass valve spring with a small washer or nut wont hurt to build a few more pounds of pressure