Discussion Forum - Northstar Chevelle Club

Bowtieman427 · Active Member

Planning next winters father son project

67ss · 1K+ Club

For a big car like that a 383 would be much better. I would not waste time or money on the double hump heads, buy something better. You can make your 327 a 383 as long as it is a large journal 327 which I beleive 67 should be. Block will need some minor trimming for the rods and crank to clear but not a big deal.

Bowtieman427 · Active Member

Thanks Chris. For some reason I thought 67 was small journal and the switch happend in 68. My friend said "leave 327 museum piece alone, wrap it in moth balls and plastic, build the 350 to 383, get some vortec type heads and you will be happy"
If I were to make the 350 to 383 is there any machining needed to the block (clearance). I am pretty sure it is mid 80s block may even be a 4 bolt main ? Sorry not real familiar with small blocks new thing to learn.

67ss · 1K+ Club

You might be correct on the small or big journal year change I can't remember 100%. But does not matter what block is used it may need some trimming for rod clearance to the pan side rail and at the bottom of some of the cylinder walls. Most machine shops will know what needs to be done to make it work.

Vortec heads would work fine but just remember they will need valve guide work for anything over 480 lift. Some heads with a little larger intake running like 180 or 195 would really let the 383 breath better. But it all really boils down to the power level you are shooting for.

What is a 327 really worth unless it is a matching motor to someone elses car who wants it to be original? Its not anything rare so I don't really think it matters personally.

Bowtieman427 · Active Member

Well is it a toss up. I have the 350 sitting there and the 327 sitting there (327 is original). If doing a 383 it will cost less doing the 350 to 383 then the 327 to 383 if the 327 is a small journal engine. Now what heads will work well for 383 ? Seen some AL 190s on ebay fairly reasonable. But there is the possible cost of a new rotating assmebly and new heads. Plus the heads may have unforseen issues as you mentioned with the Voertec heads. Difffernt intake and what not also.

Clearance issue 350 - 383 to consider ?
My goal has to be researched more. The Impala is a big car with tall rear end Th400. Thinking mild build with lots of bottom end torque.

This one we are putting together ourselves. Less on the wild side of things. The Impala will be a more of a street highway cruiser not a bruiser.

staying 327
Head machine cost. (NOT parts):
Valve job $125
machine for guides $100
harden seats machining $160
magnaflux $24
mill heads flat $55
so worst case double humps would cost $464 in machining + any parts. I think aftermarket maybe the way to go.

Leaning more toward 383 may be a much better solution. If I can make it stock looking as possible that would be a plus.

I was going to post this in project section but did not as this is still in the thnking stage.

John D · 2K+ Club

Do a google search on 383 stroker kits - you'll see they're all over the place, in varying HP's, for $600 to $800.

The only block mods I had to do on my old 383 was some slight notching on the inside of the oil pan rail, for conn rod nut clearance. They didn't hit, but I wanted a little more than the .060 that I had. A little kiss with a die grinder and burr opened it up to about .100 in a few seconds. I ran a stock pan with no issues.

My old 383 was a 400 crank/5.7" rod conversion. Had to run the 400 balancer & flexplate.
From the outside the only give-away would be the 8", 400ci SB balancer.

Chris R · 2K+ Club

Im not totally sure but your 327 might lack the majority of accessory bolt holes on the front of those heads. I agree with storing away the 327 and using a suitable stroker sbc. Or. Find a take out big block and mate your TH400 to that instead.

It takes more HP to spin a TH400 then it does for a TH350 so a nice mild BBC would be nice in a big car like that. But you already have engines on hand to work with so this may not be the best option. Just another suggestion to consider.

Dave Seitz · Mega Poster

How much power do you want to make should be the first question answered. If this is just a warmed up small block then getting something on the cheap should be no problem. Find a later style block if you want to run factory roller lifters, look for the better crank and rod kits. Some have the cheaper rods and pistons and are all from China with quality issues on machining. If you want to go nuts and build a torque monster with EFI I have an entire TPI setup for you. Some claim the TPI was the best truck engine never put in a truck with all the TQ it makes.

Tony Hoffer · Moderator

Depends on what you are after... You already have a racer.. why not do this one stock?
Had a lot of good times in a 67 Caprice with a 275Horse 327, and a glide! We thought we were the S**t when we flipped the aircleaner lid upside down and opened up the Q-Jet ..LOL

Derek69SS · Founding Member

I'm with Tony... you already have a crazy fast car, I'd just go mild with the Impala. Instead of sticking money into heads and a stroker, I'd put it into an overdrive trans and air-conditioning. Keep it looking stock, but build it for reliability, comfort, and gas mileage.

Then when you want to go nuts, drive the Chevelle.

Bowtieman427 · Active Member

383 update. Got a 350 Vortec real cheap considering it for 67 Impala. the engine was complete with all accessories. My 327 has no accessories holes in heads. The car only has Power steering not even power brakes. I agree make this a cruiser.
My dad thinks I should rebuild the 327 and keep it all original. It is pretty much original.
Thoughts:
1) Go with Vortec, how do I put AC in
2) Should I spend the $ to redo the Vortec heads or get aftermarket Aluminum ones.
3) Rebuild 327 keep all original
4) I have a 700r4 sitting in garage : ) had it for years on a trade.

I like he Vortec deal as can go hyd roller and not be to spendy. Like Vortec heads but they need new springs and machining to run lift I want. They will need complete make over and seeing what sbc heads cost may be better off buying new ones that flow even better.

Where I am at I want it all tons of power reliable and good on gas (right LS2 with 6 speed, but to cheap to go that route) I was thinking good aftermarket heads 230ish hyd roller cam 383.