Tunnel rammed 23* 421sbc

[54chevkiwi]

i have 2 x drums of MS 109 i will be testing over the next couple of months,i will report back.
OP sorry for the misdirection on your thread.

Dont sweat it, i think its fun haha.
Its been s few months, you end up testing out that fuel yet..?

[steve cowan]

i have 2 x drums of MS 109 i will be testing over the next couple of months,i will report back.
OP sorry for the misdirection on your thread.

Dont sweat it, i think its fun haha.
Its been s few months, you end up testing out that fuel yet..?

I ran a few meetings using 50/50 mix 109/98 pump but had a head gasket pushing water so the motor out and assembly of dart block and more head and intake manifold porting.
Going to dyno this one hopefully around Xmas.

[54chevkiwi]

Gas ported the pistons...
Used mahles specs, that is 8 1.5mm holes 45 degrees apart starting at 12 oclock with the pin at 9 and 3 o clock
Im a cnc machinist, but even if we did have machines available for me to use currently, theres no way i could set this up cheaper than eric at rebco machine in ks charges for the whole job! Turnaround time was 2 days too! It was flawless dealing with him, didnt even need to call him, just an email and send them in, then he sent them back with the invoice.
Thanks eric.

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[Adger Smith]

When your on the dyno If you do much testing between a single 4 and the tunnel ram manifold you will probably notice the tunnel ram will raise the Tq curve a few hundred RPM and make the middle and upper Tq stronger. Correctly sized TR's are a favorite of mine..

[54chevkiwi]

Got the shortblock together over thanksgiving weekend, no probs....
interestingly, rod bolt stretch came out at .005-.0055 with the lube and recommended torque spec..
Crank endplay came out at .007 checked with oil before assembling with lube which is nice, i didnt haveto touch that ..
Piston/deck is .005 on a couple and .002 on a couple but .003 on most, thats nice.

[54chevkiwi]

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[54chevkiwi]

Had one hickup putting pistons in..

a couple didnt go in like butter using the “tap tap TAP” method getting them in.. i get the piston has about .003 clearance so can only really go straight down but the tapered compressor can be upto .120 out of alighnment with the bore due to the top of the piston being smaller, so the idea is to square the piston up in the compressor and try centre the compressor as best you can around the piston on the deck..

You do your best and some still dont go in like butter, so the assumption is a ring hits the deck and gets pushed back into place as it goes in...
It happened worst on my last piston and knocked the bearing halfway out the connecting rod, i put the bearing back in from under the engine and thought ... i could take the piston out and check the rings, or carry on and see if the cylinder has any weird scratches indicating something chipped..
I thought odds are if the ring wasnt broke it MAY break if the same thing happens putting it back in after the check..

It didnt look like anything obvious was goin on in the cylinder compared to the butter cylinders so i crossed my fingers and figured i MAY have gotten lucky..

That was my only thing .... not being a professional it made me wonder if its normal for some to get a little hung up like that, how fragile the napier hook is if it does, and how obviously noticeable it would be in the cylinder if a napier was damaged.. i can post pics if anyone wants to see..

Cylinder prep was a clean wipe with wd40 and quickseat.

Heads arent on yet so now is the time to do anything about it..

[54chevkiwi]

Maybe i mentioned..?
I got the lindytools cutters, done a test and got the following witness mark,

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It lookes like the chamfer on the cutter just knicked the edge of the valve relief as you can see.. i didnt think it enough to put then on the mill, so i carved it open a bit more with my deburring knife, smoothed with 1000w&d and a scotchbrite by hand

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Probably an overthink but ill sleep better at night...

[rustbucket79]

I would pull any pistons that didn’t slide in nicely and have a look at the second ring, knocked a chunk of one off with that same installation issue.

Them’s the breaks of working with a 4.155 bore SBC, can’t put the chamfers you want lest you give up clamping area for the head gasket. A little chamfer, nice square piston lid, and in your case you should be able to slide the piston in with your fingertips with a bit of speed, that’ll help keep the lid square.

[54chevkiwi]

I would pull any pistons that didn’t slide in nicely and have a look at the second ring, knocked a chunk of one off with that same installation issue.

Them’s the breaks of working with a 4.155 bore SBC, can’t put the chamfers you want lest you give up clamping area for the head gasket. A little chamfer, nice square piston lid, and in your case you should be able to slide the piston in with your fingertips with a bit of speed, that’ll help keep the lid square.

I just now pulled it out.. i figured that if a professional shop wouldve had doubts about anything thats going to a customer theyd at least look, why should i be any different doing it for myself..

Anyhow, looked at it with my loup and a flashlight, no ring damage! I might go buy a lottery ticket then celebrate with the adding of chocolate to milk.

Now if only i can get it back in smoothly...

[54chevkiwi]

You know ive been thinking of all sorts of ways to reinvent the wheel

Putting a .010 slice in the compressor with the wire machine and wrapping a hose clamp around it ... cutting it in half and pushing the rings together with it while oushing on the poston.. heck, i even thought of resting the rings on the deck and squeezing them together with my finger nails one by one to get em in! Haha.

[rustbucket79]

The finger method won’t work with the oil package, but certainly works for the compression rings.

[54chevkiwi]

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[54chevkiwi]

Finishing the valvetrain friday

[rustbucket79]

That’s purdy!