Thread: 327 build questions

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I have a friend that just bought a 71 nova with a 327 in it. He wants about 400whp. I dont know a ton about carb'd motors or the SB v-8 for that matter. The motor has 2 low cyl 100 & 96 on the compression test. so a rebuild is in the plans, So here is where it all starts should he go forged pistons, rods and 4 bolt mains? or would it be overkill for his HP goal. Head, cam, roller or non, carb, intake man ect?

This is his first real project so I am trying to lay it all out for him as far as time and $. Any help sould be greatly apreciated.

-Jacob S.

400rwh...
thats gonna push it alittle.... stout bottom end and good breathing heads (not too large) and a good hydrolic roller grind will get you close....but would be better to go larger on engine size....like 400sb

What are the tolerances on boring it?and would it make much difference?

oh come on my tiny 262ci v-6 makes 317hp to all four wheels

so forged all bottom or just a good set of hyp pistons?

what is a "realistic" rwhp for this motor?

i thought they made the cyclone in 89 did they do more then one year? and for the 327 bore it .60 11:5-1 or up to 12-5-1 compression some good flowing 1.94 1-6 or 2.02 1-6 heads , headers a good 750-850 carb would help it out alot

One word...NITROUS!

First thing is to check what heads you have. DRBOWTIE IS ABSOLUTELY RIGHT You are going to need some real good breathing heads. Dont go with aluminum heads both for the cost and durability. I would definitely go with forged pistons and have everything balanced. For 400 Hp definitely go with 4 bolt mains althogh i've seen many 2 bolt mains that held well at 400hp. 327s are not that easy to come by and with that 4 in bore and a stroke of 3.25 they can produce more horsepower per weight of engine and rpms than any other v8 Have fun and do it right the first time Later DH

How you going to make a 327 4 bolt? Lots of machine work = $$.
Probably cheaper to start with a 4 bolt 350 and make it a 327. Check the crank. There are 3 "IFs. First smack one of the counterweights with a hammer. #1 If you get a dull sound it's cast iron. Save it for grandmas caprice. #2 If it rings, it's forged steel and you can proceed. #3 If it has the medium size journals, all you need is a medium journal, 4 bolt, 350 block and your'e in business. Go to MorTec.com to get journal specs. Keep in mind that a 327 with lots of mods, will develope 400 HP at somewhere close to 9000 RPM. A strong bottom end is a must, along with a super strong valve train. One more if: If you twist it that tight, eventually it WILL fly apart. Been there, Done that, and I'm not alone. One last if: If you blow N2O in it, it's going to fly apart sooner. But the fun is what it's all about right?

Wow thats a ton of info, thanks. I think his best move is to just rebuild to stock maybe headers and carb and drive the 327 until it breaks and buy/build an LT1 or atleast a 350 383 0r 377.

I just didnt know much of anything on the 327. I have a lot more knowledge of the 350 since the 4.3 in my truck is just that -2cyl.

Gassersrule- Nice memory, seriously! The Syclone was a concept in 89 but was produced in 91. they made 2994 all black of course that year and only 4 in 92, 1 green 2 red and 1 black. However they made about 6000 Typhoons (blazer) in 92 & 93 in many colors.

Originally posted by Libertysyclone
Wow thats a ton of info, thanks. I think his best move is to just rebuild to stock maybe headers and carb and drive the 327 until it breaks and buy/build an LT1 or atleast a 350 383 0r 377.

I just didnt know much of anything on the 327. I have a lot more knowledge of the 350 since the 4.3 in my truck is just that -2cyl.

Gassersrule- Nice memory, seriously! The Syclone was a concept in 89 but was produced in 91. they made 2994 all black of course that year and only 4 in 92, 1 green 2 red and 1 black. However they made about 6000 Typhoons (blazer) in 92 & 93 in many colors.

Liberlysyclone You say you don't know much of anything on a 327 but the 350 and 327 are the same block. The crank and pistons are different. The 350 has a longer crank and shorter compression hight pistons than the 327. You can't beat those 327.

Originally posted by Libertysyclone
Wow thats a ton of info, thanks. I think his best move is to just rebuild to stock maybe headers and carb and drive the 327 until it breaks and buy/build an LT1 or atleast a 350 383 0r 377.

I just didnt know much of anything on the 327. I have a lot more knowledge of the 350 since the 4.3 in my truck is just that -2cyl.

Gassersrule- Nice memory, seriously! The Syclone was a concept in 89 but was produced in 91. they made 2994 all black of course that year and only 4 in 92, 1 green 2 red and 1 black. However they made about 6000 Typhoons (blazer) in 92 & 93 in many colors.

If you were as old as I, you would remember the cyclone as a 66/67 Ford Fairlane bodied Merc with a 427 medium riser engine. They were in 2 models, GT (stick) and GTA (Automatic) Both were ground pounders of the muscle car era. And if you had the right connections you could get one with the high riser engine with 3 dueces on top. Those were the good ol days

Originally posted by DennyW
Also 1970, compitetion orange, bench seat, hurst shifter. I almost bought one when I got out of service.

My buddy bought one and I got a gold charger 383 four barrell. The wife balked at the Hemi. Wow I'm getting teary eyed thinking about the days back then.

The factory corvette 327 was at 375 rated horses in the early 60's.. My cousin had a contract building farm truck beds for the dealer and used to get chevy stuff at cost. he would build up a crate 375 horse long block with 2 fours, drive it for 6 months or a year then sell it for a profit and build another one either for his 55 post or anglia 2 door. both very fast.

Originally posted by chevy 37
Liberlysyclone You say you don't know much of anything on a 327 but the 350 and 327 are the same block. The crank and pistons are different. The 350 has a longer crank and shorter compression hight pistons than the 327. You can't beat those 327.

Well thanks then I had no idea they were the same block. I like the idea of a shorter crank. I have even had him toying w/the idea of forced induction. I am new school though and prefer FI over carbs. does this mean that heads intake manifolds ect are exchangeable with 327 & 350? does anyone make a half way decent SBC port injection mani?

Yes I am not nearly as old as some of you guys(not that its bad), I was 7 when my truck was built and GM had bad spellers in the early 90's Syclone instead of your Cyclone <--yes i know what they are. I have had some experience with older cars my first rebuild was w my mom and her 65 ford pickup w/352, I still have one piston with the FoMoCo stamped in it. others include but not limited too 40's panel wagon w a carb'd pontiac turbo v6, 68 charger w/ 504 hemi, 76 impala station wagon w 400sbc. 57 Bel Air w/396 which I am still helping with; 16 year project. I am really impressed with this Forum its a lot of help!

Libertysyclone
As the old saying goes: I would like to be back at your age and know what I do today. It would be nice to be able to crawl under the rod without having a back ache the next day. My first real Hot Rod, 48 Merc ragtop with a full house flathead, was built in 1958, during my junior year in High School. Got into Chevys when the guys with the power pack 265's started blowing my doors off.
As to your question about small blocks, just about everything will interchange. heads, manifold crank cam, etc. The trick is to match things for fit and purpose. As previously mentioned, the cranks have different journal diameters. Blocks have to match the crank or special bearings can be obtained. Heads will bolt on but you dont want small chamber heads on a block that is decked, or one containing 13 to 1 pistons. You have to pick and choose parts to come up with the correct combination for your application. Finding the interchangability data you need is a big part of the job, and the internet makes it a lot easier the find than it was 20 years ago.
As for the port injection, IMHO you would be hard pressed to beat the GM TPI setup. It works great for the street, and there are people (not me) who can tell you how to tweak it to perform on the track as well. As with all FI setups, it ain't cheap, but HorsePower is directly proportional to $$.