Gasket set recommends please

[4mulas]

So I picked up a used 383 that I was told needed a rebuild the other day only because I needed the bellhousing that was attached to it and he didn’t want to separate it. This was all good with me as the engine also had several other parts in it which I needed any like motor mounts, hp manifolds, Holley street dominator, engine tin, etc.....

When I got it home and upon further inspection it’s a 69 HP motor. So I yanked a head to have a look and it has has had a rebuild once and is currently .020 over with ZERO ridge in the cylinders and no scoring at first inspection. Well this is intriguing, I think I can use this motor as I’m looking for one to put in my Belvedere. Now that I’m contemplating using this mill I decided have a closer look at the iron heads. Turns out they are the early 516 closed chamber ones. I know that lots of people don’t like them because of small exhaust valves etc so I turned over to have a look and viola! Someone punched out the exhaust valves to the larger 1.74 which from what I read was a must if you want to use these heads. A further look showed rebuilder ID stamped into the ends of the heads with a little rebuilder button attached to them too. I’m going to take them apart to have a closer look but at an initial glance they look good.

Now the question and intention is: I intend now on finishing the disassembly and if things look okay I will re-ring the Motor and will re-use the same heads too. Having not done a motor for a LONG time I really need recommendations on a descent good quality but not killer expensive complete gasket set. The pistons in the motor are flat top and are just ever so slightly below zero deck, I haven’t measure yet but will.

If someone knows these motors and can tell me roughly what thickness head gasket to look for with these heads I would also really appreciate that!

Thanks

 

[beanhead]

Call Greg at Superformance.com, best gaskets around, and really aren't much more expensive than the cheap paper stuff. (They are sold at Mancini's and Hughes too I believe). For the head gaskets, if you can figure out your compression the easiest path is the .020-thick steel shim gasket, or if that is going to bring your compression up too much for your liking the old tried-and-true Fel-Pro 8519 PT1@ .039 thickness. If it was me, since you have everything apart, I would get a good compression measurement (which will require you to know the CC of your head chamber) and then decide on gasket thickness from there. That way you can dial in the ratio just where you want it for the type of gas you want to run, type of driving, etc.

 

[69Bee]

If your pistons are just below the deck (how far?), you can not use the steel shim 0.020" gaskets. Minimum head to piston clearance is 0.035" for iron rods. The FelPro head gaskets are going to be either 0.042" or 0.051". The best engine kit to get is FelPro (Sealed Power) 260-1001 currently at $43.99 from Summit racing.

https://www.summitracing.com/parts/slp-260-1001

You could opt for the FelPro HP head gasket 1009 which has a 4.410" bore, 0.039" thickness, and 9.9cc volume. Summit has them for $41.99 ea, you will need two

https://www.summitracing.com/parts/fel-1009

Heads started out at about 73.5cc, so with production tolerances and milling, unless you cc them, I would use 73cc. for compression purposes.

At 0.015" below the deck for the piston, I calculate 10.9:1 CR with the FelPro 1009 head gasket. With a regular FelPro 0.051" gasket 7891-PT2, you are at 10.6:1 CR. The main driver is the true deck height of the piston, and the actual chamber CC.

 

[HT413]

Felpro B/RB complete gasket set plus a freeze plug set. Be warned though, the RMS that comes with the kit is junk (according to my builder).

 

[4mulas]

If your pistons are just below the deck (how far?), you can not use the steel shim 0.020" gaskets. Minimum head to piston clearance is 0.035" for iron rods. The FelPro head gaskets are going to be either 0.042" or 0.051". The best engine kit to get is FelPro (Sealed Power) 260-1001 currently at $43.99 from Summit racing.

You could opt for the FelPro HP head gasket 1009 which has a 4.410" bore, 0.039" thickness, and 9.9cc volume. Summit has them for $41.99 ea, you will need two

Heads started out at about 73.5cc, so with production tolerances and milling, unless you cc them, I would use 73cc. for compression purposes.

At 0.015" below the deck for the piston, I calculate 10.9:1 CR with the FelPro 1009 head gasket. With a regular FelPro 0.051" gasket 7891-PT2, you are at 10.6:1 CR. The main driver is the true deck height of the piston, and the actual chamber CC.

Thanks, I will definitely measure how much below deck, it looks like 1/32 of an inch or so but I didn’t really want to say any numbers as I’d prefer to do an actual measurement. I have read 76cc’s in these heads but you logic of perhaps they’ve been decked and to use 73 makes sense. Beside if I’m on the low side it will just reduce compression by a bump to the safe side anyway. Pump gas cruiser is what I’m going for.

I’ll report back more informal I get into it. First rule of order today is organizing the shop before anything else gets taken apart. Later today the disassembly continues.

 

[69Bee]

Felpro B/RB complete gasket set plus a freeze plug set. Be warned though, the RMS that comes with the kit is junk (according to my builder).

I have used the FelPro rear main seal included in the gasket set in every single motor I have built (Mopar, Chevy, Ford, etc) and have NEVER had a leak or problem. I think the hard part (and the likely problem) are the side seals. Incorrectly installed, they will leak. I have never used any of these so-called improved seal holders, and have never had to.

 

[dan juhasz]

Don't forget to check rock auto's prices. I save a ton on Hemi gaskets over jegs , summit etc.

 

[4mulas]

If your pistons are just below the deck (how far?), you can not use the steel shim 0.020" gaskets. Minimum head to piston clearance is 0.035" for iron rods. The FelPro head gaskets are going to be either 0.042" or 0.051". The best engine kit to get is FelPro (Sealed Power) 260-1001 currently at $43.99 from Summit racing.

https://www.summitracing.com/parts/slp-260-1001

You could opt for the FelPro HP head gasket 1009 which has a 4.410" bore, 0.039" thickness, and 9.9cc volume. Summit has them for $41.99 ea, you will need two

https://www.summitracing.com/parts/fel-1009

Heads started out at about 73.5cc, so with production tolerances and milling, unless you cc them, I would use 73cc. for compression purposes.

At 0.015" below the deck for the piston, I calculate 10.9:1 CR with the FelPro 1009 head gasket. With a regular FelPro 0.051" gasket 7891-PT2, you are at 10.6:1 CR. The main driver is the true deck height of the piston, and the actual chamber CC.

Is there a calculator that I can use to do the CR after I measure the below deck measurement and try to do some sort off cc measurement on the heads. What can use for that? Not keen on using water on anything steel even though the time it’ll be in there and the fact that I can dry it off afterwards probably won’t hurt it..

I’m going to try and get to this later this aft.

 

[69Bee]

I put together a Mathcad worksheet so I didn't have to do it by hand. There are plenty of calculators out there, even on the Summit Racing website. If you post the deck height, I can adjust for the correct number. As far as the head chamber goes, I use WD40 as it cleans up well, and wont rust anything. You need to seal the valves, use a spark plug, seal the chamber with a plexiglass sheet with a hole, and a syringe or some kind of measuring device. Like I said earlier, the closed chamber head was 73.5cc OEM so an estimation of 73cc would suffice to be close.

 

[4mulas]

Will do and will report back

 

[bobtile]

Get in touch with Greg Travis @ superformanceproducts.com
Best gaskets!!!

 

[4mulas]

I put together a Mathcad worksheet so I didn't have to do it by hand. There are plenty of calculators out there, even on the Summit Racing website. If you post the deck height, I can adjust for the correct number. As far as the head chamber goes, I use WD40 as it cleans up well, and wont rust anything. You need to seal the valves, use a spark plug, seal the chamber with a plexiglass sheet with a hole, and a syringe or some kind of measuring device. Like I said earlier, the closed chamber head was 73.5cc OEM so an estimation of 73cc would suffice to be close.

Okay, both with a digital dial gauge/caliber and by laying a straight edge across the block and using feeler guages I come up with about .037 below deck, and I turned the head over leveled and sealed it and able to pour in 73 cc of varsol and it pretty much filled the chamber flush. Yes I didn’t seal it off with -plexi glass i but I sort of couldn’t wait and was curious. I think it’s safe to assume 73-74cc’s

For what it’s worth the head gasket that came of was .039 compressed measurement so I don’t know what they were going for here?

 

[HT413]

I put together a Mathcad worksheet so I didn't have to do it by hand. There are plenty of calculators out there, even on the Summit Racing website. If you post the deck height, I can adjust for the correct number. As far as the head chamber goes, I use WD40 as it cleans up well, and wont rust anything. You need to seal the valves, use a spark plug, seal the chamber with a plexiglass sheet with a hole, and a syringe or some kind of measuring device. Like I said earlier, the closed chamber head was 73.5cc OEM so an estimation of 73cc would suffice to be close.

Mathcad. Blast from the past! Is that still around? I remember using that in the early 90s in college.

 

[69Bee]

Mathcad. Blast from the past! Is that still around? I remember using that in the early 90s in college.

I used 13 & 14 '05-'10 getting my BSEET from Grantham...

 

[4mulas]

I used 13 & 14 '05-'10 getting my BSEET from Grantham...

So, from my above measurements and chamber size calculation using summit CR calculator I got 9.74:1
Sound about right? Also with the crap gas we have nowadays should I just stick with that or should I be looking for a thinner head gasket to bump it up a bit? Like 10:1 or more, maybe up to 10.5:1 ? What a good CR for a daily driver street cruiser?
Thanks

 

[69Bee]

I used incorrect bore & stroke earlier. With a 0.037" deck height, 0.00 piston volume, 73cc chamber volume, 4.270" bore, 3.375" stroke,

Gasket thickness x gasket bore
0.051" x 4.440" = 9.37:1 cr
0.042" x 4.440" = 9.58:1 cr
0.039" x 4.410" = 9.66:1 cr

 

[4mulas]

I used incorrect bore & stroke earlier. With a 0.037" deck height, 0.00 piston volume, 73cc chamber volume, 4.270" bore, 3.375" stroke,

Gasket thickness x gasket bore
0.051" x 4.440" = 9.37:1 cr
0.042" x 4.440" = 9.58:1 cr
0.039" x 4.410" = 9.66:1 cr

I read stroke is 3.38 on the 383 and the 440 is 3.75?

 

[HT413]

I read stroke is 3.38 on the 383 and the 440 is 3.75?

The 383 stroke is 3.375”, but sometimes you’ll see it reported as 3.38 - just rounded to the 1/100 of an inch.

 

[69Bee]

I read stroke is 3.38 on the 383 and the 440 is 3.75?

3.375", they rounded to 3.380"

 

[4mulas]

The 383 stroke is 3.375”, but sometimes you’ll see it reported as 3.38 - just rounded to the 1/100 of an inch.

Ahhhh, I was wondering, this Lee Herman Mopar info page confuses me a bit as they did list 3.75 up until 68 then in 69 started listing it as 3.38, I thought maybe they changed it but that doesn’t make sense.
http://www.lhmopars.com/engines.htm

What CR should I be shooting for here?