Projects SBC 350 or 400 to re-ring, port and polish

But no opinions on different Air-Gap style intake manifolds...

 

My only comment on choice of intakes is you get what you pay for. Go someplace where you can put the quality US made manifolds and the Chinese knockoffs side by side and you'll see the obvious quality difference, especially as applies to port shape and size.
Myself, I like 180* styles for everyday street use.

 

I'm primarily looking at the Edelbrock Performer RPM Air-Gap or the Dart SHP 42811000. I have the performer RPM right now

 

I thought folks might like to see a Third Generation Apache Hotrod-er.

 

I never used an airgap, but always liked the performer intakes for my engines. Edelbrock should steer you in the right direction if you let them know the full plans/intentions of the engine. And I have to give a "plus one" to what DOM said, I tried a import copy of a performer intake on an LA Mopar several years back, never could get it to run right. My buddy who works at a Machine Shop told me to pull it and bring it over, he magnufluxed it and there were several cracks in the plenum divider....now side by side you'd never know the difference...least I couldn't...may have been other issues with it, but that was as far as I needed to go.

 

I have the Dart SHP air gap intake on my 355. Using a Holley 700, think it is a 4778. It works well for me.

Also using the matching Dart 64cc aluminum heads. Cam is Lunati Voodoo flat tappet cam, 268/276 with a .489/.504 lift, 110 lobe center. But you need a decent amount of compression to get the most out of it.

 

I go the other direction I use the 350 crank in the 400 block. Use spacer bearings and no machine work needed. Sell the 400 crank and 350 block to some idiot who wants to spend lots of money building a 383. Use the 400 pistons on the 350 rods. Use some bigger valve heads. Double Humps are cool looking! Just port match the gaskets and clean them up like Squirrl suggested. No need to drill steam holes in the heads, Pack the holes in the block full of JB weld. Lots of engines have been run lots of miles with only a ring and bearing job. If they are not excessively worn they can give good service.

 

What? I've never heard this before.
400 block and pistons 4.125"
350 crank and rods
Factory 400 pistons with the 350 rod? With the 350 crank with "spacer bearings"? Will theses relocate the crank lower? If not wouldn't the factory 400 pistons on the longer 350 rods be to high?
I'm very intrigued, I'll have enough parts with one SBC350 and two 400s.
What cubic inches would this make? I really am curious please do share more!

 

the 400 pistons have a different piston pin location than a 350 piston does. so with the 350 crank and rods you get the proper deck height . The spacers are steel shells that fit in the main bearing saddles in the 400 block. then you stack stock 350 main bearings inside those spacers and that centers the crank in the block. Bill Jenkens who won a drag race or two. Used to install 327 cranks in a 400 block. A 350 crank in a 400 block makes 372 cu in of higher RPM engine than a 400 or 383 does. I always heard that if you can turn a 1000 more rPM than the other guy all other things being equal you will beat him. And the 350 crank is internal balanced so you don't need a special counterweighted flywheel. I myself use a aftermarket piston made by silvolite gives more compression. but the stock pistons can be used. I have all the stuff ganged up to build a destroked 400 right now. I will go and take a few pictures and post them.

 

Ok the first picture the blister pack is the steel spacer. the other bearings are stock 350 mains and rods and stock 400 cam bearings. the block is a two bolt main 400 with two freeze lugs. My heads are 66 chevy 327 double humps with new 202 and 160 stainless valves and a three angle valve job. My cam is a stock 30-30. I will simply pin the rocker studs. Those pistons are a balanced set. the rods are also balanced and will get new rod bolts. I will restrict the top end oil and epoxy screens into the lifter valley. The cam will be degreed in straight up (center the overlap to start with.. I know there are better heads available but this engine will be fast enough without expensive trick valve train and exotic parts. A deep sump oil pan and windage tray will keep the oil down where its supposed to be. and a stock Z28 oil pump. Of course it will have two carter four bbl carbs and reworked HEI. You might get a copy of Bill Jenkens book om small block chevys. Im going to have to dissemble the heads and clean them up a bit. There is a lot of prep work in building any engine and everything need to be as clean as possible.

 

350, easy. 400 blocks are junk.

Sent from my XT1585 using The H.A.M.B. mobile app

 

The crank stays on the same centerline.

With the stock bore, this makes a 377. I ran one in the 1980's. VERY high revving.

 

I'm no fan of the 400 myself.

 

Lots of people think that the bigger cube 383 and 400 engines will make more HP. however the engine makes power according to how much air fuel mixture it can pump. If its turning more RPM a smaller cube engine can easily cycle more air fuel than the larger cube slower turning engine. and the long stroke also has more internal friction. With the cam and top end I use you can stage flat on the floor and sidestep the clutch and not worry about blowing it up. When you start using aftermarket go fast valve train componets you start having dropped valves flat cams and interference issues broken rockers and shattered pushrods.

 

I don't like 350,s. Ive always liked a large bore short stroke engine. stuff like a 283 crank in a bored .060 327 block. I hunt until I find a 400 block that will go stock bore. I used to run a destroked 400 in a Z28 four speed Camaro I owned. A stock car guy offered me too much money for that engine and I sold it. He won a lot of races with it. I have always wanted to build another one. I finally found a good steel 350 crank that don't need turned so now I have everything I need

 

We all have engines that we are familiar with and like. I raced in a claimer stock car division and the lowly 307 was the weapon of choice for me. Dirt cheap and made decent power on a budget. The class had a lot of restriction on the cam, lifters, carb and so on.

 

My 57 dump truck had a 261. It cracked a cyl wall. So I threw a set of rings in a badly worn 307 that had been in a stock car. Used some 305 heads and a stock 283 cam small two bbl carb. That engine was really worn I suppose the ran without a air cleaner and the fine dust wore the cyls. I cut a set of .020 cast iron rings down to fit the worn bore. And its a pretty good engine for the little six yard dump truck. more power and uses less fuel than the 261. It doesnt use excessive oil has very little blow by even with the PCV pulled out of the valve cover. However when I go down a long grade with the throttle closed when I accelerate a great cloud of blue smoke fills the air.

 

I threw a very worn out 327/275 into my stock car one night for a 50-lapper. I chose to start in the rear of the field since I was sure it was down on power. It took me about 6 laps to figure how to drive it since it had a dead spot in it... bog city! Managed to bring it home in 5th place.

 

I sold some stock car guys a mediocre grease ball 350 Qjet equipped engine. All I had done to get it running was put a used steel timing gear on it. It smoked some but really ran hard they actually where doing very good with it. They decided to overhaul the mill and put a bigger cam in it. And afterwards it ran like crap. I suspected a loose timing chain. No that's not the problem they said we put in a new roller chain. So they bought another mediocre engine and I traded for the overhauled 350. I pulled the front cover and that cheep foreign made roller chain was stretched and loose. I installed a new nylon gear timing set and degreed the cam. And it ran really good again. I had installed it in a 62 GMC Pk I was driving. And those guys came and bought back the very same engine again. They didn't recognize it because I had changed intake and cleaned and painted it . Made a few nickles off of them.

 

I would just swap the go-fast pieces from engine to engine. I splurged on a pair of new SBC and SBC heads which helped make power. I could swap back from SBC to BBC in a day by myself. I always had a good SBC sitting on the side and loaned it out to someone for a couple of races.