I was guessing there was at least a stall speed difference - makes sense now.

 

It does.
Add to that the CR difference too.
I'm pretty much sold on that grind but as i said, it'll be a topic of conversation. It seems much better suited to the 357.

 

Just so we're clear, the cam is as follows:
231/339
.353/.348 lobe lift
110 LSA
HR73353-75348-110

And I explained how I have no rush in receiving the cam, he expects the step nose cores will come back in mid summer... He said is along as I don't mind waiting he's okay with it but said if I need it now just use a button timing cover (which I have on my current build) This combo isn't going together until I hurt the current one... that process could be expedited depending how eager I get lol. Stock bottom end L83 with 110k miles spinning 6300 RPMS probably has a time stamp attached to it.

 

Clear.
Here's Jones' 1st reply to my Street Performance recommendation. The same 383 in question.

Here's what I recommend
Cam# SBC, HR73353-75348-110
231/239 @.050"
.353"/.348" Lobe Lift
.565"/.557" Valve Lift
110 LSA

Look familiar?

As for blowing up the bottom end, you're probably right, time is limited.

 

You're running more rocker than I am. Looks pretty familiar lol.

It's taken 10k miles so far and I haven't exactly been nice to it but it's only a matter of time. Bores still had an almost perfect cross hatch still though. Not going to mess with what works for now.

 

I know we were talking about this a while back. I have a compression/quench result now that I opened the quench up on my 383 with thicker Felpro 1003s. Pistons are 0.013 in the hole same as before. Went from the GM Performance aka Stock L31 truck 4.060" x 0.028" gaskets to the Felpro 1003s 4.166" x 0.041". 11:1 @ 0.041" quench to 10.65 @ 0.054" quench. On Shell 93 running 29-30* timing at full load. Still working on the fine tuning but I have only seen a few instances where the knock sensor pulled 2-3° of knock retard a few times. Once was heavy part throttle in overdrive at about 2,200 rpm. Then I have seen it a couple of times around 3,500 rpm when the cam, heads, intake tract and tri-y headers really wake up and are really stuffing the comustion chambers. I pulled a couple of degrees of timing under 3,600 rpm in in the heavier load area.


Even with the stock Vortec 350 power enrichment delay in place to smooth out the torque increase it does not ping or detonate. Holds 14.7:1 for a couple of a seconds at WOT during and after the downshift. No sense beating up the friction clutches by giving the engine full power prior to a downshift.

https://youtube.com/shorts/f8L8o_MlXAk?feature=share

 

It's interesting as I've always been told tighter quench is better with higher compression... but I guess the efficiency of the chamber plays a bigger role in it? I was planning on setting quench near .035 originally but may open it to .040 just to play it safe as far as piston to valve... As far as the gasket choice itself, seems the larger bore opening didn't negatively impact performance either? I still plan to get a gasket that is slightly bigger than the head chamber...

 

I have always believed that as well, but given the problems I ran into and having those broken head bolts, I went back with those thicker gaskets to maker sure everything sealed up correctly. Felpros revised water flow through the deck surface into the head may also contribute to preventing detonation.

 

I have a set of the blue felpros in the garage, May use them if they measure out right... the .039 compressed ones. I am unsure if they have the revised orifices.

 

The question I think is still very debatable and this is why I'm still hung up on 10.4:1 and .034" quench or 10.2 and .048". That's with a compact chamber like Vortecs and also iron.
10.4:1 proved problematic although I believe further tuning may have solved the issue. DCR was 8.4 then.
This time around, at 10.1 DCR would be closer to 8-8.1:1.
If I address it as drag racing first engine then it's not a problem at the higher compression. But if the street/cruise element creeps into the picture, then the part throttle cruising is going to need more work.
As I said, this makes the case for a programmable distributor.

 

If you are going programmable distributor you might as well step up to PFI and 24x CNP but that is another matter entirely.

 

I’ve refrained in the past from saying this, and will admit when building an engine and can get the compression I want keeping quench in the .040-.050 range, I do prefer that. However I’ve run as much as .066 with iron heads and never once felt like there was an issue running that much quench.

If I’m not mistaken, seems like I remember a post from Joe Sherman on SpeedTalk saying he’s run as high as .060 and not seen any adverse quench effects and has run as much as .065 on engines with aluminum rods. Granted, I do think a tighter quench with the appropriate compression ratio is better compared to greater quench to gain the appropriate compression ratio, how much? Probably not much under WOT, but I could see where it might have a small effect on street engines running under high vacuum loads. Again, how much? Maybe just a little?

Regardless, I just don’t think quench within reason (even as high as the .066 I’ve run before) is and by itself near as important as most seem to think it is. Lots of other areas to “get right” that make much more significant impact.

One thing I will add is, historically I’ve been able to build and run compression ratios a few points higher than others in my area say they’re able to get away with. Lots of factors there but I feel like a couple things I do that everyone doesn't is to keep the gasket bore as tight as I can and make sure there are no sharp edges on the piston crowns or in the combustion chamber, including if the chamber edges sit within the bore. I believe that helps a lot when you’re on the ragged edge for the fuel you’re running - more than the difference between .040 and .066 quench - at least based on my experience.

 

The head gaskets I had in the garage (not my garage, aunts as she lets me store extra parts there in exchange for working on the vehicles) are Felpro 7733PT2. .039 compressed and a 4.125 bore... I don't think I'll be using them on this engine.

 

What's your target thickness?

 

Target is about right, bore size is a little larger than I like... I thought they were a 4.100. Other thing is they have a small twist in them from a box sitting on top of them. I don't think it is an issue but gaskets are cheap...

 

I've a set of Fel-Pro 1043's on a hook in the shop. They're .039" x 4.080". The smaller bore might be more to your liking.
I used them when I was looking to reduce the compression on one of 350's.

https://www.summitracing.com/parts/fel-1043

 

Yeah, something like that or an 1142. I haven't decided on that yet, need to measure the heads. I think the one on hand would be a little too large however.

 

So I got a message that there may be a package on the deck that looks like it could contain a camshaft.

 

Cam is from Jones correct?
If it is, I'd like to shipping container. Mine will have to cross the border with many more hands opening up the possibility of receiving two camshaft halves!

 

This is from jones, I would like to believe that the cam itself is most likely in the box in one of those hard pack plastic containers. Have about 6 hours until I'm home from work to confirm.

 

Yeah I think it was packed fairly safe. Triple boxed and no movement.

 

Well done Mr Jones.

 

Happy belated New Cam Day!

 

Lol. I wasn't expecting to be seeing this until end of summer.

 

I had a conversation with Mike Jones earlier today. It's as follows:

Question:
When examining a few of the cam recommendations you've made for myself and others, I've noticed that the lobe profile number doesn't necessarily match up with your published advertised vs .050" numbers.

Mike's reply:
Most likely, the numbers on my website aren't correct in every case.The actual seat duration for each profile should be what's on the website, but I can adjust the lift curve a small amount, and that would change the duration at .050" and at other lifts.

Thought it may give some insights into how it plays out. I find that bit of info especially useful when trying to input his data into various sim programs.

His online prices are a little off from his quotes too. At least on the lifters IIRC.