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yep last one i bought it
Good score, that will wake it up more than any other single thing you do
well i can buy a set of the yella terra ones bolt on with pushrod adj i have had 2 sets of these b4 and to be hoonest they are worth every cent,and life time warranty,i was talking on another forum thismorn to guys that worship 400s and and he said using the aftermarket pistons could be up to 80thou down the hole,so i need assistance gerg on what to do if i fit the the 78.8cc heads should i shave em a bit plus shave the block to the shithouse but what would be a good spot for the piston like how far down the hole 010 ? and if i use the closed chamber 2vs i guess really wont need to shave them or maybe just a surface and how far down the hole with them or zero deck it ? i guess around 9.1.1 or a bit bigger just around 10.1.1 ?
0.080 down the hole is massive, I will do some math here and now...

4.030/2 = 2.015 (bore radius)
2.015² x π = 12.76in² (bore area)

0.080 x 12.76 = 1.02 in³ (volume of piston to deck clearance)

1.02 x 2.54³ = 6.58cc (convert to cc)

So you can add 6.58 cc to the chamber volume and piston dish, along with head gasket thickness (same calculation as above but use 0.040" depth) to calculate comp ratio.

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If you can get zero deck pistons, go for it. Having to machine the deck down to suit your 0.080 below pistons just creates more problems like pushrod length, manifold alignment, etc.

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Righteo, so 4x4 stroke and bore with a range of 67 to 80 thou down the hole, a 78.8cc head and 40 thou gasket...

 

... youre looking at a best case scnario of 9.17:1 and a worst case scenario of 8.96:1 with 80 down the hole.

 

A closed chamber 302 head at 58cc gives you a range of 11.3:1 to 10.96:1 with the same deck depths.

 

If you have 8cc dish pistons its more like 10:1 with a 58cc head and 80 thou depth.

 

What pistons you have will govern what you want to run, but I'd be going with the 302C heads regardless. 10:1 is going to open up your camshafts a lot better than 9:1, it'll go better and be easier on the juice, too.

 

Weiand intake and E-907-P here we come!

 

 - boingk

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boingk how can a 8cc be 10.1 with 80 thou depth ? with closed chamber i thought it would be like 12.1 ? ,the factory rating on this engine was 9.2.1 with 8cc piston and open heads,but i suppose the comp height of the piston was taller,if just skimming the block for surfacing how much would be the norm ? 4 thou ? just to clean it up?

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It'll be 12:1 if you had an 8cc dome, but with the dish it's 10:1.

 

For a 'best case' scenario with that same combo and an ideal stock spec 67 though height, minus a max of 7 off after cleanup, so 60 thou piston to deck, you're looking at 10.5 to 1 compression. 

 

 

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Well that's good and bad at the same time... Good because you can boost your compression heaps, bad because you now have to carve 0.080 off the block to get the zero deck you need to work with the quench area on the closed heads. Shorter pushrods are needed for sure.

If you're going to leave the block as-is, 0.080 down the hole on a closed chamber is basically an open chamber but with the drawback of shrouded valves.

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Well that's good and bad at the same time... Good because you can boost your compression heaps, bad because you now have to carve 0.080 off the block to get the zero deck you need to work with the quench area on the closed heads. Shorter pushrods are needed for sure.

If you're going to leave the block as-is, 0.080 down the hole on a closed chamber is basically an open chamber but with the drawback of shrouded valves.

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If thats the case then i might re think it over i will ask olm8 at the machine shop if he has maybe a set of aussie 2v opens at 72cc thanks gerg hey check the factory 2 barrel inlet man its wide and heavy too,has cf casting 19714b80f887a0fe16ece6112711df4513b2.jpgf39e285d97f9a6678753c1d587fcf594.jpg94c96595c16eb12dc805b69ca124cf14.jpgc73be09c394a8726a43ce9c4af52668a.jpg41d902938de968009785aeb051b13130.jpg7f6bd3ab789ee5903b7c38a2beb8672f.jpg

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2V opens? Got a good set here if you get stuck. They'd need freight, would be about 50~60 bucks, but would do a good deal on them for you mate as otherwise they're just sitting in the shed.

 

I'd still run the closed, compression and quench be damned. You're after a torqe-monster everydayer with a bit of mongrel when you lay into it, am I right? 10 to 10.5 to 1 should be fine with the 302C heads even if they do function as an 'open' with the deck height.  If you're higher than that I'd be worried, but as it is you should be okay. Just don't crank the overall timing too crazy and you'll be fine.

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2V opens? Got a good set here if you get stuck. They'd need freight, would be about 50~60 bucks, but would do a good deal on them for you mate as otherwise they're just sitting in the shed.
 
I'd still run the closed, compression and quench be damned. You're after a torqe-monster everydayer with a bit of mongrel when you lay into it, am I right? 10 to 10.5 to 1 should be fine with the 302C heads even if they do function as an 'open' with the deck height.  If you're higher than that I'd be worried, but as it is you should be okay. Just don't crank the overall timing too crazy and you'll be fine.
I will check at the machine shop first i know he has a few sets left as i have bought them all off him over the years

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i guess we will just have to wait until the pistons arrive then do the set up should i put like 1 piston on all 4 corners to see what is going on or just do number 1 ? olm8 needs the pistons to bore it anyway and should i fit just 1 top ring 

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i guess we will just have to wait until the pistons arrive then do the set up should i put like 1 piston on all 4 corners to see what is going on or just do number 1 ? olm8 needs the pistons to bore it anyway and should i fit just 1 top ring 
I reckon don't fit any rings. They aren't required for the measurement, so I would just get all 8 rods fitted to the pistons and check all 8 in the block.

In a diesel reco shop I worked in briefly as an apprentice, they would put all pistons in and check deck clearance on all of them. There would sometimes be a few thou difference in heights, so you would take the deepest one and machine the others to match, so all sat the same distance to the deck (sometimes above). I was tasked with this job often, so it's very familiar to me.

Granted, Diesels need to be much more precise in this area as the slightest difference in deck height would affect the volume of the tiny chambers at upwards of 18:1 comp, especially on precombustion engines. But if you're going to check 4 corners on your V8, why not check all 8 pistons?

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i will go down the machine shop thismorning and check on progress on cleaning the block,i told him no rush as he was 2 weeks behind in his schedual of work ,but here is the six million dollar question what colour am i going to paint this thing ? i want to get as close as possible to the blue it was from the factory,from bc paints do a good cleveland /windsor blue in a can on e bay thats seems almost the same as what it was,i will only need 2 cans max,i want this to be the best looking engine i have ever built,mean and beefy,im going to use the std power by ford covers,but will i need the small spacer under the covers to clear the bolt on roller rockers,i think so,im gunna have to look into that petrinox dizzy thing as i would like to use my msd  that is bolted up to my spruce goose money pit crossy which is gunna get chucked in the river soon if i cant get it running better,i will put the crossy aside for a while and concentrate on the 400 conversion,only main concern is some fab work needs to be done to the engine mounts to fit on our chassis plates,my block has 3 bosses that have not been drilled ,but ford made it a pain in the ass and did not put the 4th boss ,but where there is a will there is a way ,closest engine mount is a 1972 american fairlane mount that can be modded slightly to fit into xa/xf or drill the bosses on the block and try and make a bracket for the 4th one,or you can put a spacer under the v8 chassis plates and raise the plate up about half an inch and pictures i have seen on another site worked in a xe ute but bonnet only just closed,still chewing the fat on that conversion.YvrODFPU_o.jpg

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Bolt on roller rockers fit under stock rocker covers if you have less than. 560"lift, have you priced up a crs big block mount kit, I think they do a trans mount to suit c6 as well

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Bolt on roller rockers fit under stock rocker covers if you have less than. 560"lift, have you priced up a crs big block mount kit, I think they do a trans mount to suit c6 as well
Thanks for your wealth of knowledge thom but the trans mount looks like it will slot straight in and i want to bust a myth about a c6 big block gearbox this is the first time i have ever laid my hands on one and it aint heavy i lifted the thing myself around the garage but a fmx is much heavier i cleaned it up and took the pan off and its like brand new ???? Oil was good ,i took the pan off and filter too and a normal speedo drive slots straight in and here are some interesting casting numbersa8f4b9a971931acd869be5a2f2fdf92f.jpgb2b19830ed8a1e32a5dcf7f8671b8a7b.jpge0271dd2a0a019428f815675dd7e7d24.jpgb6af77c0ea309a57d32d211635b85f38.jpg2141478a1c5e186eab4d205bb0916437.jpg42d4e295517b8bdc901a99f0a790b900.jpg64fd07867f010a42a3f25333afa2f9a0.jpg

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i garantee this box will not need rebuilding,its very low mileage i reckon,just a new end seal and work out how to hook up the old method for the speedo to work,its gunna need some bits n pieces,i wonder will the std c4 linkage rod be the same ? it was for a fmx,i drained the converter and very clean ,i might goggle to see what the std stall is on a c6 ? its matching to the engine  1971,after spending half a day on it ,its ready to roll almost,i will order a new filter and gasket,i already have the speedo drive but need a c4 type one,will havr to do some reasearch into what cog to use,i mean i know borgys what colour to use with what ratio,but i think i will use 2.92 gears or 3.08 ,the 3.45 i have in the ute i dont think is gunna suit this engine or will it ? GiRTI3OB_o.jpg

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