Chevrolet 235 12 Port Head

Here's what the guy said over at Chevytalk...
"I'm not so sure about this. I agreed that the old inline six that Toyota used in the early Landcruisers is essentially a "crib" of the Chevy 235. But, I always understood it to be a mirror image: in other words, everything is reversed from the Chevy engine. If this is correct, putting a 12-port Toyota head on the Chevy block would - for all practical purposes - be a no go."

I'm going to invite him over here to talk, if he's willing.

Tucker

 

have you considered adapting a 235 chev valve cover to the Toyota and just drive the sucker?

 

He is putting it on a 292.

 

I really don't know what the guy means because the two engines rotate the same, have the same location for the cam shaft, lifters, push rods, etc.. and all water ports and head bolts line up.

Let's say for the sake of arguement the motor is "reversed." The bottom of the head would show many of signs it however it does not and everything lines up.

I'm not saying this guy is talking out of his ass, I just really wish he would be a lot more detailed.

About just slapping a 235 valve cover on it and running it, complete toyta block and all, toyota wasn't concerned with high performance. I bet the crank is a bit different and I also bet the rods and pistons are pretty low performance as well. I'd like to get the numbers on the compression for the toyota motor but I can't find any data. I bet it's probably 8:1 or 8.5:1 at best while the 50's 235 was about 7.5:1. To really hop one up, I think you'd need a 50's 235 and a 70's or 80's toyota head. Mill the head way way way down, reshape the water ports, deck the block, run a copper head gasket and set those fuckin valves right on the pistons.

I'm going to check on this is more detail along with stovebolt and we'll see how it all lines up. Hopefully this isn't just a pipe dream.

 

Yeah, I didn't understand how you could mirror the engine and have it work out either. I posted an invite to come and chat here, so we'll see if he can make it.
I am hoping this works too!

Tucker

 

Try these links with exploded views of the head and block ,,,,is this what your looking for???

http://www.man-a-fre.com/explodedview/enginesection/cylinderheadrelated.htm#2f3fcylinder

http://www.man-a-fre.com/explodedview/enginesection/engineblock.htm#1073engine

http://www.man-a-fre.com/parts_accessories/hiperformanceengines.htm

http://www.man-a-fre.com/parts_accessories/Headers6into1ManAFre.htm

http://www.sor.com/sor/cat050.tam?xax=31044&page.ctx=cat050.tam

http://www.sor.com/sor/products2.tam?xax=5746&category%2Ectx=050%2D80&page%23%2Ectx=050

 

You rule, I found that site once and was trying to find it again to post on here. Thanks a lot man.

 

well call them guys up and ask some questions,,,

 

You say you want to pass on the Toyota engine as it's not high performance. Well I would say it's probably a lot more high performance then the Chevy 235. Also getting 350 horsepower from a 235? MAYBE with a Wayne head and then it would be a FULL RACE engine. Don't get me wrong, I'm now jonesin' for a Toyota head! I just don't think this head is going to make the 235 a dyno breaker. It should however flow better and make more power then the stock 235 head (which is the limiting factor for the 216/235/261). I'm right in the middle of rebuilding a 261 for my coupe (see pics) milled block (zero deck), 848 head, hp cam, dual carbs and full length header. I'm hoping to get between 200-250 horsepwer. I just spent $300 on head work. I wish I would have known about this Toyota head deal sooner. Anyway, keep us posted on this, I'm very interested.

 

did you ever go to the 6 = 8 web site.......

http://cliffordperformance.net/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=CP&Category_Code=C235

 

Yeah when I said 350hp I'm talking about every hop up possible, even filling the pockets in and yes it would definately be just a racing motor. I still think the 50's 235 block would be tougher than the new toyota mock up of the same design. Great looking 261 by the way.

 

If you can make this fly I'd probably build a prototype EFI and maybe a blower package for it.
Gemini EFI

 

Maybe Off topic...

Has anyone ever concidered using a 258 CI InLine AMC/Jeep/mopar engine for their rod?

You can get a low mileage engine from a junk yard with a 5 speed stick , Hyd clutch Throw out bearing, that comes with a SS tubular exh. manifold,9 to 1 comp ratio,, for very little money and much more power when compared to rebuilding a Chevy 6 cyl.

the newer versions make good HP, and there are MOPAR factory HiPo parts available

http://www.jeepconnection.com/parts/index.html

 

How about a Howard 12 port they make for a GMC inliner???

http://www.waynemfgco.com/gmc.html

 

they look a lot like a chevy 6 cyl too mee.....

http://cliffordperformance.net/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=CP&Category_Code=J

 

Is the head your locking for come on 1968-87 Landcruiser?

is the Toyota engine CID for the head your looking for 236.7 ci and 258 ci?

IF it is 258 CI,,,maybe just use the whole toyota engine???

this is about what your engine will look like when you are done...minus the toyota block,,(which looks very much like the chevy block)....

http://www.man-a-fre.com/parts_accessories/hiperformanceengines.htm

 

Yes Sir I did, but I have some racing Inline 6 back ground, for decades here in michigan Chevy In line 6's were kings of Stock Car figure 8 racing,,,now everybody has switched to 4.3 liter Chevy V6's....Lots of old Inline racing parts around here sitting in pole barns.

we built cheap engines using chevy V8 pistons and valves, used 194 CI heads
cut the crank bob weights down on a old lathe, and used 1966 to 1969 Pontiac OHC INline 6 rods ( very beefy).

That welded chevy v8 head was done here in Detroit by Charley Newby 30 years ago with a Cast iron head, for the super six class at Mt. clemmons speedway, worked great,,,that alluminum head should be much better.

to do this toyota to chevy head conversion may require custom pistons at $85 each, and rebalancing, and you still have the weak 235 rods....I would Guess that the Toyota Oiling sytem , crank, rods, and bearings and block are much better, stonger,a nd lighter than the old chev 235 engine,,,Yet it looks very simular,,,

So Maybe by drilling and tapping a few holes or making an adapter plate you could just swap in the toyota engine and have a Better, cheaper product in the end.

I am just asking a few questions thats all...

and i appologize if i have offended anyone here.

 

i'm a land cruiser freak. and have thought of this same thing before. it might work. the early cruiser engine is a 1f, and the 2f came in 73 or 4?? it only has a bigger bore and better oiling system. and then in 87 they did the 3f it was destroked and had EFI and the sucked!!! i know i had one. 92 was the last year for the push rod motors. i had a new offy intake for a cruiser engine. very cool. and they are much better than any old 235!!!! i had a extra 2f engine and thought about putting it in my A. so people would say what the hell is that?????? they have a longggg stroke 4 inch very slow turn up. but i like em. i drive a 85 fj 60 daily with a wber and header. sucks gas but i love it!!!!!!!!

 

Unfortunately WayneMfgCo is out of business - whether its permenant or temporary I don't know. All I know is that there are 40 heads sitting waiting to go, but until the mess is sorted, nothing is moving.

Damn shame though.

 

I believe the head we're looking for is the 236 toyota head. And to answer your question about just swapping motors if it ends up being another.. well, that kinda changes everything doesn't it? I mean a motor swap is a motor swap. Some of these guys are running allison aircraft engines. There's just something bad fucken ass about taking your original engine block and hopping it up to the extreme.

One guy mentioned maybe it wouldn't be as high performance as I'm expecting. Maybe not but it will damn sure breathe better and that's one of the biggest flaws with the 235.

EFI and a blower sounds like an awesome idea. Force as much fuel and air down those ports as possible.

Too bad about wayne, I would like to see all those heads on ebay sometime soon though.

 

Keeping a close eye on this one.

 

Close but No cigar!!!

I just got back from measuring a 2F Toyota head, and a 1F Toyota head gasket against a 235 head gasket. Both Toyota examples were the same.

Both were about 1/2" too long, when I placed the Chev headgasket in the centre of the toyota head, there was 1/4" or so overhang, with the toyota head being bigger. There was marginal differences in the combustion chamber placement in the 2 centre pots, but naturally the difference was amplified the further out from centre you looked. The outer combustion chambers of the Chev head gasket covered some portion of the toyota valve.

suffuce to say, if it could have been done - some-one would have discovered this long ago.

Oh Well - Back to modifing the "848" head I have here.

 

Damn dude that's terrible news. It's so damn close though, a half inch? shit maybe we can modify it to work.

 

Every bolt has to be moved.

May be easier to laminate a new head

 

Ah well, it was a nice idea. I'll still look into it a bit more and see what else I find.

I know a lot of you have said or want to say "if it could have been done then it would have been done already" but if everyone thought that way, nothing would ever be done.

 

This is a great thread! I love the outside of the box thinking, as the owner of a 52 Chevy running the stock 216 and having a 235 sitting in the back of my truck waiting to have some magic worked on it I will keep following the "12 Port exploits" started here!

 

guys, lets look at the options and goals here...

#1 goal,,,Keep the old stove bolt chevy inline 6 ( 1962 and older).

#2 goal,,, make some more power for a reasonable cost.

lets examine the basics....

CID, 235 and 261.... this plenty enough displacement to make at least 200 hp.

cylinder head.... only 3 inlet ports,,, air flow is ver poor at RPMs over 3,000 rpm.

combustion chamber ....spark plug is by exh. valve...a design that greatly reduces spark knock.


Lets compare this stove bolt to another GM 6 cyl, the Buick 231 ci V6 which later became known as the 3800.

From 231 CI they make about 200 hp, and lots of Torque.

the key here is TORQUE.

The 235 I6 is never going to be a high RPM engine,,,heavy, crank, rods, and pistons, along with a poor flowing head.

The one modifaction that will increase low speed torque and horse power is a SUPER CHARGER.

MANY GM 3800 V6 ENGINES CAME WITH FACTORY SUPER CHARGERS....

The sizing, packaging and engineering for a 231 CI 6 cylinder has Already been done! You guys HAVE a 235 6.

Adding a super charger to a 3800 added about 50 HP( from about 200 to about 250 ) but it really helped torque.

Installing a 3800 blower to a 235 would...

negate the need for a better flowing head,, the blower forces the charge into the head.

negate the need for a race cam, the blower forces the charge into the head.

negate the need for Hi compression pistons,,, the blower raises cylinder pressures.

Negate the need for a High rpm engine, the blower will make lots of power below 5,000 rpm.

Also just by having a few pulley of different diameters you can go form MILD to wild in a few minutes. run a small pulley for long trips, and when yu get there install the big pulley on the blower to have lots of tire burning power.

And BOWERS are Very COOL.

 

here is link for some 3800 blowers, they come in long and short snouts,,,lot of them in junky yards....

http://stores.ebay.com/American-Supercharger

 

Possibly you could build it like this...

come out level from the intake ports with 3 steel tubes.

these 3 steel tubes merge into a steel plenum box who's size is about 8 '' X 8'' by 6 '' deep,,, the plenum box is divided internally with a 8 X8 plate ( so the box has a up stairs and a down stairs ( two spaces 8x8x 3 ). the 3 intake ports merge into right side of the the Downstairs stairs plenum.

the 3800 super charger mounts up side down to the bottom of the plenum box, and blowes thru the bottom of down stairs plenum, the downstalrs plenum flows into the 3 intake port tubes.

Out of the the Back of the 3800 blower ( the Inlet side ) comes a 3 '' tube bent in a tight 180 bend . this 180 tube runs UP to the up stairs plenum and hooks into the back wall of the up stairs plenum.

The flat roof of the up stairs plenum is machined to accept you chioce of carbs...( maybe 4 one barrel carbs) ...

so the air flow is like this

carb to upstairs plenum

back of upstairs plenum to 180 degree 3 '' tube

down the 180 degree tube into the back of the 3800 SC ( inlet side)

from outlet of the 3800 Sc to bottom of down stairs pleunum.

from the right side of down stairs plenum into to the 3 horizontal intake ports

 

Already done that on 250-292s been driving one for five years. The late Eaton from 3800s is harder to mount than the earlier T-Bird but can be done . The finished product is kind of ugly though. There is no need to run different pulleys. Eaton has a by pass for non boosted driving. It takes less than one h.p. to turn blower when not in boost. I turn the blower on my truck pretty fast(3 to1) but can still cruise about 75mph without going into boost.On 235 cubes an Eaton M-90 will make over 10 lbs. boost. If the engine only made 150 h.p.(not too hard to do with cam. headers and good exhaust.) The added boost would make the total h.p.about 250. 3800s only rise about 50 h.p. because they turn the blowers very slowly. As I said I have been driving my truck for 5 years @10-12 lbs. boost and I run the hell out of it. The torque produced is phenomenel. One customer we boosted could not even turn his tires unboosted . With 6 lbs.boost the same car could fry the tires down to shreds.Picture shows blower mounted on right side so that all stock brackets could be used for power steering etc.
235 installation would be very similar.
Gemini EFI