Vintage 302 chevy.

THERE'S A DAMN GOOD REASON WHY THE 383-406 cubic inch SBC combos are currently far more popular than the older 302-327 SBC engines and that's simply because the cost will be fairly similar but the results will favor the larger displacement combos by a wide margin if you do your home work and build both to their respective full potentials
and I doubt the cost would be all that much different after either build was completed
if a 302 can make 1.35 hp and ft lbs of torque per cubic inch you get
about 408 ft lbs and 408 hp

if a 383 can make 1.30 hp and ft lbs of torque per cubic inch you get
about 498 ft lbs and 498 hp

lets put both those engines in a 3400 lb car and calculate the results assuming 80% at the rear wheels
http://www.wallaceracing.com/et-hp-mph.php

302-408 flywheel hp x .80=327 hp in a 3400 lb car that should give near

12.71 et at 106.3 MPH

383-498 flywheel hp x .80=398 hp in a 3400 lb car that should give near
11.91 et at 113.5 MPH


http://garage.grumpysperformance.com/index.php?threads/tbucket-engine-project-dart-shp.3814/

http://garage.grumpysperformance.com/index.php?threads/the-new-215cc-vortec-heads.266/#post-35948

http://garage.grumpysperformance.co...vortecs-on-a-400-short-block.4462/#post-17247

http://garage.grumpysperformance.co...ding-sbc-crate-engine-heads.13041/#post-69348

http://garage.grumpysperformance.co...cu-sbc-in-vortec-head-build.12080/#post-57865

http://garage.grumpysperformance.com/index.php?threads/port-and-runner-math.148/#post-34936

http://garage.grumpysperformance.co...ed-up-fuelie-heads-for-cheap.2099/#post-50526

http://garage.grumpysperformance.com/index.php?threads/heads-for-302-sbc.11492/#post-52993

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-68861

http://garage.grumpysperformance.co...sbc-vs-383-sbc-dyno-results.10210/#post-40509
 
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I've made some progress lately. I have also learned that sonic testing is not as popular as it sounds on the internet. It has only taken me the better part of 2 months to find someone with a tester and I should get those results back friday. By the looks of the machine shop i would agree all those new dart blocks really don't need all that so my block has travelled far and wide to find one. No luck in Vegas if you can believe that.

Anyways the heads got cleaned up and they pressure checked good. They said the seats still looked good. They needed to bead blast the ports and break the plugs loose in the water temp sensor holes.

Crane recommended a set of 96886-16 springs for my cam since the recommended spring was to large for my seats. I chose comp cams 10 deg. tool steel retainers 1732-16 vs crane titanium and whatever comp locks the shop uses. I'm looking into a set of ferrea valves possibly f6303 and f6143 I have to bounce these #'s against what the shop found.
 
each area has machine shops with different tools, experience and unfortunately some machinists have attitude issues
and don,t seem to think delivering top quality work at reasonable prices and on promised delivery dates are a reasonable expectation.

related threads
http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-55314

http://garage.grumpysperformance.co...ting-started-in-the-car-hobby.339/#post-60187

http://garage.grumpysperformance.co...y-in-building-a-good-engine.11682/#post-54682

http://garage.grumpysperformance.com/index.php?threads/precision-measuring-tools.1390/#post-52466

http://garage.grumpysperformance.com/index.php?threads/bare-minimum-tools.11026/#post-51823

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.co...e-springs-and-setting-up-the-valve-train.181/

http://garage.grumpysperformance.co...g-and-installing-connecting-rods-pistons.247/

http://garage.grumpysperformance.co...tion-of-crank-durring-short-blk-assembly.852/

http://garage.grumpysperformance.com/index.php?threads/maximizing-piston-to-bore-ring-seal.3897/

http://garage.grumpysperformance.co...ing-parts-and-a-logical-plan.7722/#post-51341

http://garage.grumpysperformance.com/index.php?threads/parts-prep-cleaning.6255/#post-51146

http://garage.grumpysperformance.co...embling-an-engine-correctly.10363/#post-43802

http://garage.grumpysperformance.com/index.php?threads/machine-shop-sequencing.4460/#post-11720

http://garage.grumpysperformance.com/index.php?threads/installing-splayed-caps.7267/#post-24528

http://garage.grumpysperformance.co...block-cylinder-wall-thickness.976/#post-22976

http://garage.grumpysperformance.com/index.php?threads/block-prep.125/#post-10122

http://garage.grumpysperformance.co...cking-blocks-heads-for-cracks.3363/#post-8862
 
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This is true grumpy. A lot of the problem I had with the tester is that not a lot of people request it around here so most shops dont bother with one. Most places rely on one shop to have one and everyone just farms it out to them. The shop I went to took my block to that other person and the tool ended up being broke and they didnt feel like fixing it. I had to contact another shop and they referred me to a private guy that luckily one of my friends is a close family friend with so I'll make out better that way verses going through the shop.

I still intend on going through my current shop as choices are limited around here and I can drop in at anytime and monitor progress rather than take it far away to someone I can only talk with electronically. I have very high standards and expectations when it comes to detailed work but in this instance I have to trust the abilities of the shop as I can't boss them around and expect good quality like I can at my job.

I don't know if this is a good thing but I did turn them on to the tool steel retainers they didnt have any idea when I asked about them so I had to show them what I was talking about. You learn something new everyday.
 
I've got about 4 semi decent machine shops in my area (within 40 miles),
theres more "machine shops" in that 80 mile diameter circle, but from past experience,
I would not trust many of them to de-grease a block,
let alone do anything like precision, machine work, after seeing some of their previous work.
two have the sonic test equipment ,and both can bore & hone and line home blocks,
one specializes almost exclusively in cylinder head work, and cylinder head repairs

http://garage.grumpysperformance.com/index.php?threads/finding-a-machine-shop.321/#post-55314
 
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The shop I chose seems to do a lot of work and I've seen some good reviews and recommendations for it. I'll just have to learn from my own experience with them and create my own opinion.

I should have my results back from my sonic test this evening. I talked to my friend and he said it didn't look too bad. Took about 45 mins to check it and $60. He even took it by another machine shop and talked to them about the #1 cylinder and they said it would be around 300 to sleeve, deck and hone. Good thing is they think the rest of the cylinders should clean up with a hone and be able to stay at .030. I'll post the test results later.
 
Heres the results. #6 doesnt look so well on paper but I took the time to measure everything manually and those numbers I could not duplicate. I kept getting around .200 so I think there may have been something going on with the tool when they started on this hole. Here's the block info; 3858180....327ci... 64-67 year ...2 bolt main Date Code: April 20, 1965. Believe this is a tonawanda block according to research.
 

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1&3 being the thinnest

Yes, I hadn't measured there yet was more focused on #6 thrust side before I measured pin sides. Electronic tools are nice but you can't always believe them. In this case this guy is retired so he had to refresh him self on the tool again so I believe some of these numbers may be off. They thought it might take .030 to clean up the water damage in the #1 cylinder so that one will be sleeved for sure.
 
Been working on removing some of the rust out of the water jackets. Just let it set for 24 hrs and drained and checked it when I got home from work seemed to work alright but filled it back up for another 24. Thankfully its gonna be over 110 here all week so its free heat to keep the block warm. I'll get a picture of the left bank before I fill it for a comparison on how the metal rescue works.1497921137917.jpg
 
20170619_190444_zpsfuf4aww0.jpg

Here's a comparison of my 492 angle plug head (top) with a 462 (bottom). This I thought was interesting because you could definitely see how much material was removed. I didnt get a picture of the outer row of bolt holes but it looked like close to .100 had been removed.
 
thanks for posting the clear picture of the two different cylinder heads
 
Heres another. This gives a better look at the unshrouding.
20170605_162656_20170620062150241.jpg

492v462b.jpg

492v462a.jpg
 
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Both of those heads came off the same engine??? They are clearly VERY different.
Are you planning to re-use them? That 462 head will take a lot of work to make it like
the 492, but still one is angle plug and the other is straight.
 
Both of those heads came off the same engine??? They are clearly VERY different.
Are you planning to re-use them? That 462 head will take a lot of work to make it like
the 492, but still one is angle plug and the other is straight.

Nope just a comparison between the two. It would take quite a bit of $$ and work to bring the 462's up to where my 492's are in the terms of machine work and porting. I'm close to the 1000 in parts and labor now. I was thinking about having them flowed but have decided the money is better spent elsewhere.
 
upload_2017-6-22_12-47-13.png

I read that you must grind these cooling passages deeper to maintain coolant flow on excessively milled heads.
Just 1/16" ought to do the job - compensate for the amount of material removed from the deck surface.
 
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