draco

I'm starting the build on my 327. So far I have the block bored .030 over, I have ARP main studs, oil pump studs, and a new melling oil pump kit on its way. I want to keep the factory crank (the 327 cranks were forged), but I'm not sure on the rods, is there anything special about 1966 327 rods? What is the benefit of shot peening connecting rods? Am I better off just getting new rods?

Also, I'm not sure which pistons to get. I'm aiming for 11:1 compression using a pair of 461 double humps, 1.94i, 1.5e. Need input on hypereutectic vs forged vs cast pistons, and which one is best for max street/light strip. Input on pistons rings is appreciated too.

I'm wanting to run either the comp camps L79 repro cam or their 30-30 repro cam, unless i get good advice from someone here. Looking to run 3.73 rear gears, and a 700R4 tranny.

BTW this all goes into my 87 project car.

JTS

Why such a high compression ratio. Somebody correct me if I'm wrong, but you won't be able to run on pump gas with those cast iron heads.

draco

I was told by a local engine builder that 11:1 is ok with a high quality 93 octane fuel.

TTOP350

iTrader: (8)

That may be a tad optimistic about that comp ratio and 93 oct.
Y are you wanting to use the dub hump heads?? They really aren't that good compared to the newer stuff..
I would use the best/lightest forged piston you can afford.
have them setup 4 the LS type rings for less drag/ power loss.

JTS

I would get a second opinion on that.

I have a 355 with vortec heads (can't remember the cam right off hand) and it has roughly a 9.2:1 CR and I usually have to run premium. Sometimes I can run mid grade but it had to be from chevron.

You might be able to get away with that CR if you run aluminum heads.

Apeiron

What's the objective of your build?

battmann

iTrader: (9)

i built an almost identical engine to what you described for my 1984 Trans Am. the car was quick as hell and a lot of fun, but i needed to run a mix of half 100 octane and half 93 octane. was a pain planning trips around where to get gas. i also had over heating issues at first, but solved those by installing an aluminum radiator and electric puller fan.

this was the engine parts list:
1966 327 bored 30 over
Speedpro hypereutectic domed pistons (approx. 11.5:1 compression)
Crane Blue Racer Duntov 30/30 cam
Stock 461 heads with Crane roller tip rockers
Edelbrock RPM Perfomer intake
Holley 4160 carb
MSD ignition system
Heddman shorty headers with Flowmaster cat-back system

engine pics below. i drilled and tapped a hole in the head to mount the alternator like that. i also made a custom breather and PCV system since the stock corvette valve covers had no breather holes:





the car also had a TH350 tranny and 3:73 gears. here's a dyno clip and the dyno sheet:

InfernalVortex

iTrader: (4)

11:1 is definitely way high.... a lot of it depends on dynamic compression ratios... but 11:1 is really pushing it for just a big cam to make it work on pump gas, especially with old double hump heads. Some modern heads like some Vortecs can get away with a lot higher compression ratios than old school heads. I'm running 9.8:1 on mine with no issues. Vortecs seem to be able to hit 10:1 if you run premium without too much worrying, but it depends on the cam.

I would aim for around 9.5:1 if I were you.

five7kid

iTrader: (14)

Shot peening improves resistance to fatigue due to manufacturing surface stresses. It doesn't make the rods stronger.

'66 was small journal. Rods are probably available, but as long a you use good rod bolts and keep RPMs reasonable, the stock ones should be up to the task.

The only disadvantage to forged pistons is their initial cost, and possibly a little more engine noise. Outside of that, they are superior to the other types in every way.

Cam & heads - go modern. No performance benefit whatsoever going retro.

draco

I have the double humps available, but a modern head would be nice. Point me to a decent priced aluminum head? Battmann, your info is awesome, but i'd like to see more than 240hp, im optimistic that i can make at least 300hp, id be even happier with 1 hp per cu. In. What can i change to make that happen? My application is about 1/2 street 1/2 eighth mile.

InfernalVortex

iTrader: (4)

I would run some vortec heads and flat tops. Should get you in a 9.0-9.5 CR I would imagine. Not sure, but Vortecs with 3.48 strokes and flat tops are at almost 10:1 when it's all said and done, so with a 327 it's a nice mild streetable SCR that you can still get some decent power out of.

https://www.thirdgen.org/forums/post...s-best-builds/

The first post is a Vortec crate engine.

He says Vortecs dont really benefit from high CR's, and everyone knows Vortecs are incredible at making good street power on a budget. If you're trying to make 383+ ci smallblocks run at 6k RPM +, the Vortecs start to lose their luster in a hurry, but for a 327 I think they'd work really nicely. With that factory LT4 hotcam roller cam he put out nearly 400hp from a little vortec 350.

mcbchild

iTrader: (1)

Battmann, very nice looking ride. I had a 327 bored out to a 331 in my old 1978 TA with 12.5 to 1 domed pistons and a mechanical flat tappet cam 298 dur .535 lift with some roller tip rockers and 461x double hump heads with 2.02 x 1.60 valves installed with screw in studs and the 327 motor was from a 1967 chevy with the small journal steel crank. It had some factory steel rod with some ARP rod bolts and main studs. Thing would scream to 8000 rpm and made like around 450 hp. I know that the compression was very high and had to run airplane fuel 110 octane, but with the t-350 trans and 3500 stall, I was able get decent vacuum for the power brakes. This was back in 1990 and was a fun little motor in that car. I had a 10 bolt posi and 3.42 gears. Car would run in the high 12s all day, but as everyone says in this post that you can get some better heads and a mild roller cam in that motor with 10 to 1 CR and still be in the 12s all day. That would be a really nice street motor, but just remember to have the good bolts installed internally and that motor with run in the 6500-7000 rpm range safely. You will have a lot of fun with that engine and in out 3 gen car bodies which is a little lighter than the 2nd gen fbody, you will not need as much cr and cam to get this in the 12s in the quarter mile. I will I still had my 331 and would get like an 82-88 camaro/firebird and throw that motor in there. I would have lowered the compression to 10 to 1 max and some nice but cheap World products iron heads and have alot of fun with it on the street. Maybe around 80 to 90 percent street with a small amount of track duty maybe like 2 to 4 times a year at the track. Just remember, the goal for you is fun which means you don't need to spend alot, just having the internals to match what you have for weight, gears, drive train and suspension.