Inliners International Forums General Discussion Engines GM 4 cylinders 151 153 181

Does any one want to talk about GM 4 bangers? I just got a '80-'81 Iron Duke rebuilt long block. I thought they used the same bellhousing as our 6s but it's the same as the 60* v6, some S10, Jeeps, and Dodges. I want to use a trans with a standard Chevy bolt patern. It has a cross flow head. They are strange looking. Will the 181 crank fit the 151? Will a SBC flywheel fit? One piece main seal? There are two holes on the right side of the block that have cam drive gears in them. One is for the distributer. What is the other one? I think I may have been better off just buying a 181. Beater

Beater,
From what I have found you have the jeep/ pontiac/ s-10 version. There are performance heads available for that engine. That engine continued and was used in Fiero's.
Super duty parts were avail thru GM, heads, intakes and everything else.
The head bolt pattern is almost the same as the 153/181 GM engines.
I think they share cams, timing components, front covers .

153/ 181 have the standard SBC bolt pattern on the bell housing. The nice thing with 181's is they produced them currently. I have a few from forklifts with 17000 hrs on them! They are a 4" bore engine. One piece rear seal to. Different heads were used.
The forklift engines used a siamesed intke port head.
Boat engines used both a 8 port head and the siamesed head. I think there maybe 2 versions of 8 port head. There is also a aftermarket replacement head.
Flywheels for 153/181 are the same as SBC for the corresponding 1 piece or 2 piece seal.

The 2 holes on yours is to put the Distributor in 2 different locations depending on application.
Not sure on your flywheel or bell for the 151 you have.

Thanks Tom. I have an old Clifford catalog that lists cams for these. The 151 has one part number and the 153-181 have another. They all use the same timing set as our 6s. They share the same cam bearings and timing cover. Valve covers are the same for all heads. The bell housing pattern is called the metric or small corporate pattern.
Valve sizes are 1.5 &1.72 and in some 181 heads Mercruisers 1.6 & 2.0+. Some Volvo, OMC, & Mercruisers ane the 153s and 181s. !20 and 140 hp. The Iron Dukes seem to produce 90 to 110 hp. GM used the Duke in lots of Chevy, GMC, Buick, Olds, Pontiac applications. Jeep used them for a couple of years in CJs and DJs. Mine is going in a '26 Chevy roadster. After the MS of course. Maybe with the MS. They used a single BBL TBI on the Dukes and there is an unmolested '88 Chevy Citation at Pick&Pull. Beater

The 151 VC is different than the 153/ 181.

I'd like to find a intake for the 153/181. Want to put one in a field buggy for the kids. Keep it tamed down with the 4 cyl.

A turboed 181 would be a little beast! The kids could cover the field in no time.

SPA does make a turbo manifold for the 153/181 siamese head. Hmmm.

Well,,, w/you being a dealer for them (SPA), you should be able to get it cheap for him. Correct?


MBHD

There are 3 different 8 port heads,.2 marine and 1 industrial. The only part off the Iron Duke 151 you can use on a 153/181 is the pushrod guide plates. All 3 of the 8 port Gaskets , ., and the 8 port compared to the 5 port ., , the smallest 8 port is the industrial engine.

Here's some more info.,
The 153,230 and 307 all share the same bore and stroke.
The 153,230,250 and 283,307 all share the 3.875” bore and the 181, and 327 ,350 share a 4” bore.
The 153,181,194,230 and 250 and Vega 4 share the same rods, 1.030” wide at the big end.
You can use the stock or aftermarket straight or splayed cap's on your 4 or 6 engine if the are for the small block Chevy & for the small journal crank. >>
if you run a roller cam you use chevy SBC lifters and Olds 350-455 tie bars..>>
The 153,181,194,230,250 all share the same timing gear and the crank gear is shared with the 292
Push rod guide plates you use the 350-455 Olds or the 151 chevy for the 1977-79 engine.

bore and the 181,250 and 327 ,350 share a 4” bore.

250 what,,,,, has a 4"bore?
Typo?

MBHD

Don't we all wish it did!
Pete

Sure do, & a stroke of 3.75- 3.85"

MBHD

Most likely if the 250 = 3.875" bore x 3.530 stroke

The 153 is 3.875 X 3.25 and the 181 is 4.0 X 3.60. Do they both use the same main bearings? Can the 153 be bored .060 like the 6s. Can the use small block rods or is there a width issue like with the 6s? Beater

Yes to the overbore,main bearings show up as different parts numbers, no to the SBC rods (The 153,181,194,230 and 250 and Vega 4 share the same rods, 1.030” wide at the big end)

So , a 153 bored .060 over with a 181 crank would be about 175ci. Custom pistons? Is the valve spacing the same as the 6s? Would 1.60s and 1.94s work? With the 5 port head would you use lumps in the intakes or just skip it and go to the 8 port with the big valves? I kind of like the idea of using a '62 Chevy II 4 banger in a bare bones 1500 lb roadster. The last 4 cylinder I had was a Morris Minor Woody. It was fun to drive. Beater

With a 5 port head the lumps are a dirrect fit. I would use 1.84/ 1.6 for a moderate motor and 1.94/ 1.60 on a hot one.

The 5 port will perform very well.

The good 8 port comes with 1.84 intakes. The individual runners are a plus and will allow for a smoother running engine with better fuel distribution.

Either head will need custom headers and possibly a custom intake.

150-200 HP and 1500 lbs could be alot of fun to drive. Tom

I've been told that you can turn down the 181 mains to use them in the 153 and use Dodge Omni 4cyl. rods and stock pistons? I'm still trying to confirm this. The person who really has the knowledge is Sarge Nichols in Ft. Smith Ark. who is the 4 cyl. advisor for the club.

He should get on here and advise us. Here are some pictures of the Duke .

Phew, I've got to sit down, my head is spinning! Such interest!

All L4 motors are pretty balance-sensitive above about 2.2 liters (134"), it's not an accident many engines fall between 2.0 and 2.2.
It's just not possible to balance them enough to take the shaking out (except a counter-rotating weight, etc.).
The best way to reduce this is:
1. automatic transmission to un-couple the driveline from the vibe
2. big rod ratio to reduce the side thrust (long rod, short stroke, both)
3. absolute minimum reciprocating weight (light rod and piston with short compression distance and small pin)
4. squishy motor mounts
5. high quality damper specifically for this engine

Except for the automatic transmission -- perish the thought! -- that fairly describes my 2008 Mazda Miata, which is smaller but revs freely and gets itself on right well. It is quick and smooth.

God's Peace to you.

d
Inliner #1450

Is the 2.2 Vega or the Quad 4 related to these engines. We know the Vega uses the some rods. What else? The cam in my 151 has two drive gears and hole in the block in the front and back of the right side. Is that two different distributer/oil pump locations?

If you want something different to power that sheet metal you salvaged from Harrah's use your 151 and add a 392 hemi head. That's a SBC head on a 151 in the background.

I'm kinda" going for "cute." How close does the SBC head come to fitting? Would it have an advantage over the cross flow or the 8 ports?

Those engines were at the Arias shop in CA, also saw one of their (Arias) Hemi heads for the BBC on one too. I think they are all one off units to just try and they all probably had one-off cams etc. to make them work.

Do any of the 151s or the 3.8 V6 bell housings have a standard Chevy trany bolt pattern? Do the 151 starters bolt to the bell housing?

I believe the V-6 3.8s are B.O.P.(Buick,Olds,Pontiac) bolt pattern? Not a Chevy engine.

MBHD

OK, Thanks. I didn't know what BOP meant. That will help in my searches. That pattern is also called the small corporate and the metric pattern. Now to find a bell housing that will fit between a 2.5 and a Saganaw. Beater

gearhead (mod for the BB) may know what is needed.

Tom, these sites may help you, http://www.fiero.nl/forum/Forum2/HTML/097456.html , http://ironduke7.tripod.com/dukefaq.htm and http://quad4rods.com/index.php?page=shop...t&Itemid=100041

Gary, Thanks! There is a lot to study there. It ought to keep me out of your hair for a while. I just got back From Reno where I ate ribs at the Nugget cook off and made a deal for a 153. Tom

Now we're gettin' somewhere! I shouldn't show you this until I grab a few 181 cranks.
181 Duke

Just to confuse you a little more look at the Mercruiser 470 engine which is basically 1/2 a Ford 460 with a Chev bellhousing pattern. You can 460 pistons and an aftermarket Ford head (Boss?)and upper valve gear. http://www.jalopyjournal.com/forum/showthread.php?t=256713&highlight=mercruiser ., and ., http://www.jalopyjournal.com/forum/showthread.php?t=289260

You have talked to me, you know how confused I am, why would you throw a whole new engine into the mix? The GM possibilities are almost endless. We have GMs that won't bolt up to GMs and you add a Phord that does bolt to a GM. Man, I thought you were my friend. Beater

A fenderless model a sedan with a merc 4cyl has been on my list of future projects for a while. The potential of the super cobrajet head combined with the ability to bolt to a gm trans makes this a very appealing engine choice.

The biggest problem. with the 470 is the alternator which can be replaced with a kit for a GM single wire. I've seen a single new RHS aluminum 460 head at Summit when they changed models going for under $200.00 bare. I'm pretty sure some Ford racer screwed up one head and have spares around.. ""quote" Man, I thought you were my friend. Beater ", Tom I am being freindly because I never mentioned the Quad 4's that look like Offy engines or the Ecotecs that can put out up to 1400 HP using a factory manual and sourced parts.

Tom how about a Chevy engine (Ecotec) with bellhousing adaptor that we made from a blueprint we got from Jack Roush Performance (Ford) ,

Jalopy, nice job. Put some pics of your dragster here. You guys are beyond me. I'm still trying to get my head around all the interchange on the 151,153, & 181 versions. These are where I'm going. As usual I'm a few decades behind. Were you and Dave still with us at the Nugget when the T with the Quad 4 came by? I know a guy in Carson City who has a built Q4 for sale for way less than he has in it.
Thanks to everyone who is posting here. You are teaching me a lot. This build would be a natural for a megasquirt with two single throat GM TBIs. If I can work it I want to get the Duke at the wrecking yard with the harness and ECM. I need to get rid of some stuff. Beater