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I picked up 2 tenths going from a 1300 stall to a 2600 stall GM converter. Picked up another 6 tenths going to a Yank 3200 stall 10 inch converter. Does the 200r4 lock the converters? My car had a 4L60e thus the converter was the lockup variety. Mileage stayed the same on the highway, but my city mileage went to ****.
It is a lock up, but analog control. There are ways to control it and alter it. Also can be eliminated, but I'd rather have the fuel economy or I would just stick with the TH350 that is in it currently. Looking at doing a 2400-2600 stall.
A simple home-made controller for the lockup will do what you need. Momentary push-button to activate it; brake pedal will disconnect it (to protect the lockup clutch from being left 'ON'). Circuit uses one standard auto relay. If you want the diagram for it, send me a PM with your e-mail address (so I can send it back to you).
With this approach, you still have capability for lockup when you choose to use it.
Picked up my block yesterday from the Machine shop. I am guilty of not taken pics after I picked it up. 190k on it. Could use a hone and run standard pistons. Block is in great condition. Recommendations were to align hone, bore .30 over and deck the block. I discussed the project with the machine shop and got figures. For the price and the guarantee, I am better off assembling it. 90 days or 4k miles. Ehh, the car won't be ready in 90 days. I gave him an opportunity to sell me the rotating assembly and He gave me a price significantly higher than what i can get it for through work, Which with the warranty, I'll bring my own parts in.
Pics are of the block and the roughest journal on the crank as it came apart. I am satisfied. with a $250 short block.
Congrats on L31 ! Did you get a good crank & rods too?
Hot tanked plenty blocks/heads but prefer bake & blast.
dunno your plan, but manufacturer NPR America offers an L31-specific piston in ten-over, repeat ten-over. Many L31 that weren't abused can clean up at ten-over.
good luck with it !
Originally Posted by djquik1
Picked up my block yesterday from the Machine shop. I am guilty of not taken pics after I picked it up. 190k on it. Could use a hone and run standard pistons. Block is in great condition. Recommendations were to align hone, bore .30 over and deck the block. I discussed the project with the machine shop and got figures. For the price and the guarantee, I am better off assembling it. 90 days or 4k miles. Ehh, the car won't be ready in 90 days. I gave him an opportunity to sell me the rotating assembly and He gave me a price significantly higher than what i can get it for through work, Which with the warranty, I'll bring my own parts in.
Pics are of the block and the roughest journal on the crank as it came apart. I am satisfied. with a $250 short block.
? I'm confused? Did your shop bore it 0.030" ... or at this point, is that only a recommendation ? One of the few drawbacks of otherwise great L31 blocks is how they typically have relatively thin cylinder walls as well as shorter wall length. Per above, suggest bore only as much as needed to clean up. OE type L31 replacement pistons ARE available as small as +0.010" and +0.020"
Other than more $ for shop, Are there any good reasons for either:
* decking block ? or
* line hone ? or
* +0.030" over versus hone-std, or +10 or +20 ??
And, what about the crank? What, if anything do they suggest there? Surely, if they suggest an align hone of block's main saddles, there should also be obvious, concurrent, Uneven witness wear on crank's main journals & bearings, right? Just based on that one good pic of "worst" journal ... and fact it's a ROD journal (not main) ... I suggest that crank MAY need only a professional polish. Again, I see limited pic and no measurements.
There are a variety of affordable head gasket thicknesses available; in order to optimize quench/squish.
Suggest step back & reconsider
JMO ...Unless that block has been abused/overheated or you WANT to deck in order to achieve a certain height, seldom a real need to deck.
Similarly, unless motor's been real hot/abused oil-starved/obvious visual cues, seldom a real need for align hone.
Same goes for bore; bore only as much as is Required to achieve Your goals. YMMV
? I'm confused? Did your shop bore it 0.030" ... or at this point, is that only a recommendation ? One of the few drawbacks of otherwise great L31 blocks is how they typically have relatively thin cylinder walls as well as shorter wall length. Per above, suggest bore only as much as needed to clean up. OE type L31 replacement pistons ARE available as small as +0.010" and +0.020"
Other than more $ for shop, Are there any good reasons for either:
* decking block ? or
* line hone ? or
* +0.030" over versus hone-std, or +10 or +20 ??
And, what about the crank? What, if anything do they suggest there? Surely, if they suggest an align hone of block's main saddles, there should also be obvious, concurrent, Uneven witness wear on crank's main journals & bearings, right? Just based on that one good pic of "worst" journal ... and fact it's a ROD journal (not main) ... I suggest that crank MAY need only a professional polish. Again, I see limited pic and no measurements.
There are a variety of affordable head gasket thicknesses available; in order to optimize quench/squish.
Suggest step back & reconsider
JMO ...Unless that block has been abused/overheated or you WANT to deck in order to achieve a certain height, seldom a real need to deck.
Similarly, unless motor's been real hot/abused oil-starved/obvious visual cues, seldom a real need for align hone.
Same goes for bore; bore only as much as is Required to achieve Your goals. YMMV
I won't be using the crank, was just showing the 190k of wear on it. With that being the rough journal I thought it was in good shape. I plan on off loading the rotating assembly that came out of it, everything appeared to be in good shape.
No work has been done other than remove all bearings, freeze plugs and galley plugs, hot tank and magnaflux and measure. No cracks, good foundation to build.
Going 383 forged rotating assembly. Will be using ARP studs for the main caps hence the align hone. The .030 over bore keeps piston price down with common configurations instead custom ones. The reason I was given on the engine coming out of the donor was a overheat and head gasket failure with a cracked head.
I did not get the heads in the purchase so I can not confirm that. I did not plan on decking the block but machine shop recommended for the build. Align hone was recommended because of using studs on the build. Sorry for the confusion.
Line bore is not necessary on a running teardown assuming no scrub taper on the bearings.
Decking is necessary if the piston is too far down in the hole......
Bore .020 is the smart move as it gives one more overbore and most machinists do not want or cannot bore .010....they have to hone it .010.....a lot more work. A boring bar will not be consistant or may chatter cutting .008 or .009.... .020 gives the bit some meat to bite into.....
I would grind the crank .010/.010......and ask for the low side of the nominal spec for a better chance of good main clearance with .010 main bearing out of the box. The same can be done by resizing the rods if you reuse them by honing out to the high nominal....if you do this, replace the rod bolts with ARP or Pioneer.....
OE L31 pistons (like most other modern pistons) use thin metric ringpaks.
Whichever pistons you choose from; ensure they also have thin ringpak (that's partially why your bore has so little wear).
A stroker crank made for longer 6" rods and concordant shorter pistons will more easily balance and with less or no Mallory metal.
Line bore is not necessary on a running teardown assuming no scrub taper on the bearings.
Decking is necessary if the piston is too far down in the hole......
Bore .020 is the smart move as it gives one more overbore and most machinists do not want or cannot bore .010....they have to hone it .010.....a lot more work. A boring bar will not be consistant or may chatter cutting .008 or .009.... .020 gives the bit some meat to bite into.....
I would grind the crank .010/.010......and ask for the low side of the nominal spec for a better chance of good main clearance with .010 main bearing out of the box. The same can be done by resizing the rods if you reuse them by honing out to the high nominal....if you do this, replace the rod bolts with ARP or Pioneer.....
Jebby
I'm not reusing the crank or rods. Going with a stroker crank and 6" rods new so you would resize new parts? Going with 6" rods, not sure on I beam or H beam yet
Originally Posted by ebbnflow
OE L31 pistons (like most other modern pistons) use thin metric ringpaks.
Whichever pistons you choose from; ensure they also have thin ringpak (that's partially why your bore has so little wear).
A stroker crank made for longer 6" rods and concordant shorter pistons will more easily balance and with less or no Mallory metal.
RIngs is something I am looking into further, I don't plan on adding a power adder but plan on overbuilding in case I change my mind and put at 125-150 shot n2o kit on down the road.
Line bore is not necessary on a running teardown assuming no scrub taper on the bearings.
Decking is necessary if the piston is too far down in the hole......
Bore .020 is the smart move as it gives one more overbore and most machinists do not want or cannot bore .010....they have to hone it .010.....a lot more work. A boring bar will not be consistant or may chatter cutting .008 or .009.... .020 gives the bit some meat to bite into.....
I would grind the crank .010/.010......and ask for the low side of the nominal spec for a better chance of good main clearance with .010 main bearing out of the box. The same can be done by resizing the rods if you reuse them by honing out to the high nominal....if you do this, replace the rod bolts with ARP or Pioneer.....
Jebby
very, very few off-the-shelf AUTO pistons are available in +0.010"; for motorcycles, for decades they're commonly available as "first over" aka +0.25mm aka +0.010"
AFAIK, NPR America is only supplier of production OE replacements for AUTO in +0.010"
OK sure any of the performance piston manufacturers will make pistons in any diameter you wish $$$$, Again referencing OE-type production replacement pistons.
I wouldn't expect to resize New rods ... but it's happened w/ Eagle SIR rods.
Apparently, Eagle's pre-hone QC failed and it didn't properly torque the caps Before final hone. ...Then, upon shop doing its own QC check, when properly torqued, the rod was Not round.
Strongly suggest: properly torque New rod on bench 2-3 times and then measure w/ inside mike to Verify if rod's round. If not, get a bud to check it. If still not round it's time to either return it or re-size it. Just one of the aspects of a good build; pro or diy.
I wouldn't expect to resize New rods ... but it's happened w/ Eagle SIR rods.
Apparently, Eagle's pre-hone QC failed and it didn't properly torque the caps Before final hone. ...Then, upon shop doing its own QC check, when properly torqued, the rod was Not round.
Strongly suggest: properly torque New rod on bench 2-3 times and then measure w/ inside mike to Verify if rod's round. If not, get a bud to check it. If still not round it's time to either return it or re-size it. Just one of the aspects of a good build; pro or diy.
I plan on doing that. won't be my first build, just my first one in 20 yrs. So behind the times on some of the new tech and how things have upgraded and why they were done the way they were.
it maybe an optical illusion, but they look rough; far too rough for success with any steel shim gasket. I'll agree, it seems they Need decking.
Should be able to go .010 and be ok. I will also be using Felpro 501 SD headgaskets. So all in all, still should be ok with a flat top piston and 6" rods and still be pump gas friendly with my 64cc heads.
