68hemi

My 1965 is an original engine 300 h.p. car. I am going to increase the cars power one of the two ways below. I an NOT going to pickle the original engine and buy a Blueprint engine or like type engine.
I have been slowly collecting parts to convert my original 300 h.p. to either a 350 or 365 h.p. configuration with a 1965 aluminum intake, carb, air cleaner and engine dress up items. My 300 h.p. engine already has 2 1/2” manifolds.
I am looking to do either a factory spec 350 h.p. engine or a stroked 383 with a factory solid lifter 365 h.p. cam and aluminum heads. Think “stealth.”
The 350 h.p. configuration will be just the factory h.p.
If I go with the 383/365 look-a-like it will be well over 400 h.p. If I go with the 365 h.p. I will need to replace the original 1965 factory rods as they are the weak link of the engine. So in that case it would only make sense to me to stroke the engine to a 383 as long as I have to buy rods.

Many have commented in the forum that a factory 365 h.p. Car really needs 4.10 gears to see it's full potential.

Here are my questions.

1. With my original wide ratio trans and 3.70 gears do you think this combo would over come the "out of the hole" problems that the 365 had with less than 4.10s with close ratio trans had?

2. My original 300 h.p. engine of course has the smaller balancer that I believe will be OK with the 350 h.p. configuration but wonder if I need to step up to a larger balancer with the 365 h.p.?

3. Are there any other things I need to address depending on what configuration I would go with?

Boyan

The rods are weak for both.

MikeM

That gear set will be fine unless you are drag racing. 3.70 with close ratio isn't really that great for normal driving.

If you're a cruiser and holding rpm down and throttle opening pretty much closed, I might go with the small balancer. But I'd rather go with the big one, just in case.

I've never had any problems with any of the 327 rods and don't know anyone who has except one person who was drag racing and was turning 8K. Your results may vary. If you don't beat on it, the '66-'67 rods should be okay unless there is something wrong with them before assembly.

Changing rods for "piece of mind" and/or "for the children" is not something I want to argue about.

Nowhere Man

What cam will you be running? The 365 is solid. Where as the 350 is hydraulic. Besides the timing cover and balancer the 365 got the bigger oil pan and a idler pulley. It wasn't until 66 they got the stronger rods. But like said it’s only a problem when drag racing or getting the rpm high in the red line. But if your going to rebuild the engine it’s cheap insurance to get better rods

68hemi

To clarify If I go with the 350 h.p. I would just be changing the cam to the L82 hydraulic and would not be doing any other internal changes and would not be worrying about the rods due to the lower red line of that cam.
If I go with the 365 h.p. I would be concerned about the rods with the higher red line so I would change the rods which would be included in the stroker kit to 383 cubes. I would be using the factory 365 solid lifter cam and also aluminum heads.

pop23235

If you plan on reving past 5k, change the balancer/damper, save your crank!

wesmigletz

If you stroke the 327, are you going to turn down a crank with 350-sized mains? Unless you have one already, I think you'll need to find a SJ stroker crank used somewhere. I've been looking for one without success for my 57's 283. Pro gram engineering has splayed main caps for the SJ blocks. I wouldn't hesitate to stroke your 327, I like the low end, and being able to blow my tires away for a whole city block.

In the past, I stroked a 283 in my old 59 vette and a 327 in my old 62, and got both into the 12s through factory heads. My 62's stroked 327 ultimately went 12.14 @115 with a 3.36 gear and an 1800-2200 generic converter.

Vette5311

Put in the good rods, not that expensive and good insurance.
If you go 383 the extra torque will make the wide ratio / 3.70 a non issue.
I would go with the larger balancer to give the crank a better life.
As I am sure you know, the camshaft will be the "heart" of what ever you are doing. You can't over think it.
Good Luck

TCracingCA

In your opener, you are all over the place!

Base 300 hp engine to 350/365hp and now 383? And you have been collecting parts not knowing where you are going!

Addressing the 3.70 first, a great ratio for off the line street/strip, and it helps some on the cruise! If you want to rip everyone stop light to stoplight, then get a marginally better 4.11 for sheer acceleration, but let’s ask you first what rear tires are you planning? As anything in the stock range is a waste for like 4.11 gears!

Stock rods are weak! I have ran Z-28/LT-1 units highly profiled and with upgraded rod bolts, and those were adequate for 6800 redline ops! I full float them always! If you are running lighter wrist pins, lighter pistons, then the stock rods are far less stressed! And some people have pounded on their engines with these, and had pretty good life!

I stopped debating with 383 fans years ago, but a 383 is a far cry from high revving solid lifter 365hp engines! The 365hp manifold too is poor flowing! The LT-1 is a dual plane better. The Weiand Slealth is the best dual plane design.

Big stock balancers old school worthless for driving rpm range! Get like a Rattler or Fluidampr if you don’t have high engine temps, for a better harmonic and proper dampening!

68hemi

No matter which h.p. configuration I go with it will have a “factory look” fo it. 1965 350/365 intake, carb, 2 1/2” manifolds, air cleaner etc. think “stealth.”
It will be one of the two engine configurations I have spelled out in the 1st post.
So far (and as I expected) I think the wide ratio trans and 3.70 gears will be the best combo for me with my 50/50 around town and freeway driving and sounds like it will be fine out of the hole. I will step up to a larger fluid damper as recommended regardless of which configuration I go with.
Are there any other recommendations given my concept for each of of my stealthy upgrade possibilities?

ghostrider20

Sounds like you are two sides of a spectrum. Make it a 350 hp or a 383 365 with aftermarket heads
Apples and Bananas.

In my opinion, there is not enough gain going from a 300 hp cam to a 350 hp cam. They are both hydraulic cams will never be high rpm cams.

If you want it to appear correct and your limitations end there, this is what I would do.

Aluminum heads, Lt-1 cam, and a 350 crank with new rods, then dress as a 365 hp motor.

Robert61

I wouldn't put a fluid filled damper on a lawn mower. I seen the results where they snap the snout of the crank off and then not only did they lose a crank but in those cases they lost $1800 worth of titanium valves. Just do a google search on fluid filled dampers. Every NASCAR engine has an ATI damper on it that should tell you something. Also look at what the crank manufacturers have to say.

SWCDuke

I don't recommend stroking an ...870 block. The main bearing webs are thinner than later blocks with less material if you bore the main bearing bores for 2.45" mains. Also, reducing a large bearing long stroke crank to small bearing journal sizes reduces crank strength, and, more important, results in much less torsional stiffness that can result in catastrophic torsional flex. Crank torsional stiffness is why GM went to larger journals when the SB was stroked to 3.45".

If you want to go long stroke get an OE '67 ...657 block or a ...512 service block. Both have the rear crankcase vent and notches for both small and large bearings, and GM processed them for both small and large bearings. If you find one processed for small bearings, align boring for large bearings is all that is needed. The large bearing retainer notches are already there.

Forget the 30-30 cam. If you want to go with mechanical lifters, use the LT-1 cam, or L-46/82 cam advanced four degrees on a 327 if you prefer hydraulic lifters.

Search for threads started by ghostrider20 and Dave McDufford circa 2006 to learn about the 7200 rev "327 LT-1".

Whatever you do at least buy a new set of Eagle SIR5700 rods for $250, and remember that you select the cam to achieve at least 80 percent of peak torque at 2000 for a responsive road engine and massage the heads to achieve maximum top end power and revs.

Duke

Vette5311

......if you want flat tappet and not roller check out Comp Cams 12-673-4. It is part of their nostalgia series. It copies the old 30-30 but with different ramps and much tighter lash. LSA is 112 so it works good with a 4 speed. Has idle like 30-30 but better performance. I have used it in a couple builds and customers really liked it.

68hemi

First I have never been warned about stroking a 327.
I have a 657 block in my 383 in my 57 but I am going to stick with my original block in my 65. Do you think it is a problem when revs would not exceed 6700? You think the LT-1 is better than the original 365 h.p. cam when revs will be no more than 6700? With exhaust manifolds and the 585 cfm carb I don't think going past 6700 revs will do anything for increased performance.

I like factory grind cams as they were designed to be used with exhaust manifolds unlike the aftermarket cams that are designed for use with headers.

Gavin65

How often do you plan on spooling up an original block to 6700 rpm's

MikeM

Consider yourself warned.

Previously plowed ground.

https://www.corvetteforum.com/forums...l-block-2.html

ghostrider20

My 327 build (LT-1 cam, Crower rods, pocket port job) the rest all stock L76 made useable power to 7200 RPM with the 2818 stock Holley carb. No hydraulic cam is going to 6700 RPM so that leaves you with a solid cam. The 30-30 was a very “peaky” cam. It woke up at 4000 rpm. Below 2000 rpm it was a soggy toad. The 30-30 cam needs open headers and 4:11 gears.

Gavin65

This is right on the money, although I wouldn't call my 65 a soggy toad down low, I have headers and 410's spool it up a bit on the launch, with the wide ratio and your at 4 grand the rest is a rush. I love the noise it makes.

SWCDuke

If you limit revs to 6700, you leave useable power on the table. A properly built 327 LT-1 peaks at 6500 with a little rolloff to 7200, and the beginning of incipient valve float is about 7250. And that's with OE VALVE SPRINGS, second design, '67-up that are about a buck apiece from Federal Mogul, VS-677. I recommend a normal redline of 7000 to leave a little margin.

The system engineering and testing was done nearly 15 years ago. Massaged heads, high strength rods, LT-1 cam with carefully set up OE valve springs, everything else basically OE equivalent. It's a proven configuration. . It makes 80 percent peak torque at 2000. The 30-30 cam won't do than and doesn't make meaningfully more top end power. End of 30-30 cam. It was a mistake from the get-go for a road engine. Why do you think GM came out with the LT-1 cam and discontinued the 30-30 from service parts and substituting the LT-1 cam for all prior 30-30 application? Figure it out.

Do the thread search I previously recommended and learn all about it instead of daydreaming

Duke