Author Topic: Needing help on v8 block to 4 cyl conversion.....  (Read 14359 times)

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Offline Peter Jack

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #15 on: December 12, 2012, 11:49:46 AM »
If you Google SESCO midget you'll get all sorts of information on that engine. They were the engine that really started to put the Offy and V8 60 away.

I remember a flat crank being used in a SBC in Formula 5000. It sounded really neat, similar to an engine with 180 degree headers, but the harmonics were such that every time the car came back to the pits you had to do a full bolt check! I never heard of the four cylinder having the same problem.

Pete

Offline manta22

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #16 on: December 12, 2012, 12:34:07 PM »
Pete:

"I remember a flat crank being used in a SBC in Formula 5000. It sounded really neat, similar to an engine with 180 degree headers, but the harmonics were such that every time the car came back to the pits you had to do a full bolt check! I never heard of the four cylinder having the same problem."

The first time a Cosworth DFV engine was tested in a Mirage sports racer, it shook all the needles off the gauges.

Regards, Neil  Tucson, AZ
Regards, Neil  Tucson, AZ

Offline desotoman

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #17 on: December 12, 2012, 02:16:39 PM »

I have seen the odd used Chevy flat crank for sale over the years..... they are probably not popular so cranks of this design may be sitting forgotten and collecting dust.....maybe put a "wanted" ad on here and/or on Racing Junk and see what comes up.


If you are looking for a Chevy 180 degree crank, I have one I would sell. It is a bryant, 3.48 stroke, two piece oil seal,
2.100 rods as I remember but would have to look. Never used.

Tom G.
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Offline fastman614

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #18 on: December 24, 2012, 01:36:06 AM »

I have seen the odd used Chevy flat crank for sale over the years..... they are probably not popular so cranks of this design may be sitting forgotten and collecting dust.....maybe put a "wanted" ad on here and/or on Racing Junk and see what comes up.


If you are looking for a Chevy 180 degree crank, I have one I would sell. It is a bryant, 3.48 stroke, two piece oil seal,
2.100 rods as I remember but would have to look. Never used.

Tom G.

Tom has a crank for sale.... this makes an almost instant 178 to 180 cu. in. Chevy 4 Cyl. engine (a 4.000" bore with an .030 or .060 overbore)..... use a SB2 head and some good efi.... and you have way over 400 hp!... OH - you DO need a special cam as well.... but, if you are getting a custom cam made, have them grind the NON used lobes so that all of the parts can be transferred to the opposite side of the block and your cam will be good for the other side too.
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Offline fastman614

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #19 on: December 24, 2012, 01:46:08 AM »
Pete:

"I remember a flat crank being used in a SBC in Formula 5000. It sounded really neat, similar to an engine with 180 degree headers, but the harmonics were such that every time the car came back to the pits you had to do a full bolt check! I never heard of the four cylinder having the same problem."

The first time a Cosworth DFV engine was tested in a Mirage sports racer, it shook all the needles off the gauges.

Regards, Neil  Tucson, AZ

I recall a visit with Smokey Yunick.... in Daytona Beach, Feb 1974 - in his dyno room - we talked about 180degree cranks..... his words were - "They sound really nice when wound up and they do seem to make a few extra horsepower but when they are running at low speed (RPM) they sound like the pistons are swapping holes.....".... he also alluded to the inability to get a good balance job on them - at least so that the fasteners would not shear off the safety wire as they wound themselves out......
No s*** sticks to the man wearing a teflon suit.

Offline Jack Gifford

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #20 on: December 25, 2012, 12:50:08 AM »
I always listen closely to quotes from Smokey. But I hope that the shaking is somewhat more manageable in an inline four, since a one-eighty degree crank seems to be the only choice- if not wanting to deal with the odd-firing alternative crank choices.

Update on my V8-to-DOHC-four conversion: I finally tired of pencil-pushing and started making chips. Don't expect a build thread, though- progress is slow enough, without taking time to document it here.
« Last Edit: December 25, 2012, 12:57:00 AM by Jack Gifford »
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Offline deucemac

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #21 on: December 25, 2012, 02:42:42 AM »
I talked to Bruce Crower several years ago and he had managed to build a flat crank that didn't shake your teeth out.  He told me that they had a cosworth in the shop and he examined it because it was really smooth and had a flat crank.  He reverse engineered it and found out the Brits used only half the bob weight to balance the crank.  he tried the idea and it worked for him.  He was thinking of making a flat crank to put in the flathead in his '34 street hot rod at the time. Bruce retired to his home shop and I never followed up as to what he did.

Offline racergeo

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #22 on: December 25, 2012, 02:46:24 AM »
 I have two 180deg cranks. The SBC one I had  destroked to 3.9". It is an up, down- down-up rod pin design with the corresponding roller cam. It's so old the roller is smaller then a 274 XE Comp hyd. steet cam. Didn't want to rev the shakers to high. Also have a 427 stroke BBC Crower and roller cam with an up, down, up, down rod pin arrangement. Hope to make time some day to make one of them a runner. I bought them cause I heard the engine that Gale Banks built for a TF dragster run with a turbo on it. Nothing in the auto world sounds as cool. (It could never get traction!)

Offline martysmilt

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #23 on: December 25, 2012, 12:19:32 PM »
FWIW, there was (possibly still is) a company called CESCO..... they made "flat" cranks for Chevy V-8s.... you would end up with an even fire cylinder bank on either side of a Chevy V8 this way.... it was how they made inline 4 cylinder engines using Chevy V8 blocks away back when....

I have seen the odd used Chevy flat crank for sale over the years..... they are probably not popular so cranks of this design may be sitting forgotten and collecting dust.....maybe put a "wanted" ad on here and/or on Racing Junk and see what comes up.

SESCO Owner Ron Hoettels and partner in a rear engined car, Greg Nelson pitted next to us last year for speed week.  He still loves building and raceing.  He is one of the few people I know with a dyno in his house!

Offline Rex Schimmer

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #24 on: December 25, 2012, 12:24:57 PM »
Flat crank V8 war stories! Back in the mid 80s when Ascot was still running a guy ran a Keith Black hemi with a 180 crank in his sprint car. Sounded great! and went like the devil when the track was sticky. He was hot lapping and drove her into 3 real hard, lifted to get it set and when he picked up the throttle 7 rods and pistons plus the crank and the pan fell out on the track! Appears the aluminum hemi block didn't like the shaking either.

Rex
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Offline fastman614

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #25 on: December 26, 2012, 02:44:21 AM »
I always listen closely to quotes from Smokey. But I hope that the shaking is somewhat more manageable in an inline four, since a one-eighty degree crank seems to be the only choice- if not wanting to deal with the odd-firing alternative crank choices.

Update on my V8-to-DOHC-four conversion: I finally tired of pencil-pushing and started making chips. Don't expect a build thread, though- progress is slow enough, without taking time to document it here.

I don't think that getting a good balance if used as a 4 banger engine will be a big problem as it will be an even fire engine in that configuration.
No s*** sticks to the man wearing a teflon suit.

Offline johnneilson

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #26 on: December 27, 2012, 06:09:08 PM »
Balancing a 4 banger is not easy, the pistons accelerate at different rates from the top of the bore to the bottom.
Therefore, the only solution is to lighten the piston assy's as much as possible and all the same.
The crank can be done, no bob-weights needed.
A damper helps on the snout to keep the fasteners in place in the car.

J
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Offline woz

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #27 on: February 10, 2013, 06:40:12 PM »
I have a question regarding the Pontiac 194" or IH 196" half V-8's...If you were to install the 4 cylinder rotating assembly in a V8 block would it work and if so, would there be a manner in which to create some boost from the dead "left" side of the engine to enhance the functional "right" side? From an engineering standpoint not sure if it would be feasible to install a set of left side pistons and rods to just push air into a plenum.  Obvious balance and check-valve issues come to mind but with weight not always being a major consideration??

I remember reading somewhere many years ago about a racer that broke a Tempest block and I seem to recall them running the slant four engine internals in a 389 block.  I vaguely remember it having a header only on the right side and block off plates on the left side exhaust ports.    

Woz

 
« Last Edit: February 10, 2013, 07:08:59 PM by woz »

Offline SPARKY

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Re: Needing help on v8 block to 4 cyl conversion.....
« Reply #28 on: February 10, 2013, 07:59:56 PM »
Build a v-8 with pushrods out of 4 holes put dummy lifters in the dead holes so you don't loose oil pressure there will be about 2.5 to 3% loss loose the Ford 9" (4.5% loss) put in a GM 7.5 and you get  to pick up 1%  when you want to go to a 6 or a 8 just reinstall the push rods and lifters
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