Inliners International Forums General Discussion Hi Performance Chevy II 153 4cyl, turbo or N/A?

Hi all, new guy here from Arizona! I have a 71 cj5 that had a 153 swapped into it, at some point in its life. Engine had been rebuilt at some point with flat top pistons, and a marine cam. Engine sounded good, but never really ran right (worn out carb and cracked exhaust mainifold). So I have decided to modify it.
The long block so far is taken care of. freshened it up with new rings and bearings, put a slightly hotter cam in it. Specs are 204 at .050 and .441 lift, 112 lobe sep. head has been gone through, 1.94 intake valves, 1.60 exhaust, divider removed and lumps installed, I will do some porting.
so here is where im having a hard time deciding what to do. I plan on building my own intake. I have header flanges to build my own header, but I also have a spa turbo manifold. SO im thinking go N/A, usually better response and not as many parts to break. it would consist of the engine above, 32/36 dgev, and 1 1/2 long tube header.
Turbo engine is engine above, holley 350 carb modified for blow through, spa manifold, IHI turbo from ford turbo coupe should build boost fairly low. external wastegate, probably no more than 8psi. just don't know how blow through and off roading will work
The jeep weighs less than 2500 lbs with me in it. has 5.38 gears, 3 spd trans, will get granny gear in future, has a .70 overdrive. Want it to drive well on and off road.
So what do you guys think? Thanks!!!!!!

Sounds like a cool build. Don't see many turbo 153's around, but most any mods done to the 6 cylinders can be transferred to the 4 cylinder with similar results.

Thanks! Im thinking I should be able to get close to 120 125 hp n/a, probably 200 to 220 boosted though. My biggest worry is how well the holley will work off road.

sorry double post

Sounds like it's going to be a beast! Awesome! With that gearing, it will walk up a wall. What turbo are you going to use? I'm assuming it will be some sort of T25 because of your displacement?

Its a little IHI similar in size to t25. It was used on 87-88 ford turbo coupes with the turbocharged 2.3.

The 153 in the Mercruiser form is a 120 HP engine. The 181 is 140 HP. I am building a .040 over 153 with a 181 crank for 175 ci. My head has 1.86" intakes and 1.60"exhaust, lumps, port work, milled .030". I had a custom cam ground by Erson. It has forged Ross flat tops at zero deck height. It will run a pair Zenith one barrels and a tube header. I expect to do better than the stock 181's 140 hp. I pick up the block from the machine shop tomorrow.

That 153 in N/A form will easily make 150HP. The turbo will increase the tq by almost 10% per PSI.

Well you built the head so I'm counting on you. It is finally going to get put together.

The 153 n/a will really make 150 hp with the small cam I plan on installing??!!??!! Im excited to get the lumps mounted and start doing some flow testing and porting.

Here are pictures of the head tlowe built for me.

"The turbo will increase the tq by almost 10% per PSI"

How does the math work on that?

Looking good,, but can you remove a lump, hard to see the sawzall cuts.

MBHD

Well , maybe I miscalculated the turbo tq. It will be atleast 5% or more per PSI.

Hank,
You gotta try it before knocking it. Don't make me do more vids. It is the fastest way to pull them out.

A sawzall is faster for sure, I just think its funny.

When I take out the boss, I have the head bolted down on a mill table, mill out the boss w/an end mill, then I machine the surface for the nut I used.
The head stays bolted down in one position for both operations.



At the time I did this head, I never heard of bolt in lumps, that was 25 years ago.

That is exactly what I need while I recover, more vids to watch.

MBHD

I still like the method described in the PES instructions. It makes a sawsall sound civilized and a mill sound down right sissified.

Thanks for posting Beater,
That is just one step over using a chisel & hammer.

MBHD

That is the first I ever seen any paper work for PES. Even the set I bought in the mid 90s Didn't come with anything Other then were to drill the head to bolt them in. NO other info.

Pretty basic machine work for sure. I think that paper is in the shop somewhere. Maybe it needs to be framed and hung on the wall. I got them from Lee. He may have put that together.

It's a really good turbo!

Someone sent me a set of them one time to look at and it had that paperwork in it. It seems the best I can remember to drill down to close to the depth of the floor with a big drill bit and take a hammer and chisel it out. Then dress it up with a grinder. I guess that's how he did it.

Results matter. The rest is just means to an end. I have logged more hours with a hammer than I have with a mill or sawsall, though I haven't tried that yet.

Using a hammer for most jobs is a real statement! Talent?

The persuader, beat to fit, something something, what other sayings are there for the use of a hammer?


MBHD

IMHO the ft/lbs per psi isn't straight-forward.
Beginning with the fact that a NA motor is running at perhaps 1.5 psi vacuum @ WOT, just bringing the cylinder up to ATM (zero) is adding 1.5 lbs, or about +5.5% VE (and probably ft/lbs) at sea level.
Any boost at all is cumulative to that figure.

Hey all, been slow working on the 153. The plans have changed somewhat. I have decided on dropping the turbo and am now building a supercharged 153. Everything else is the same. I will be using an Eaton m45 from a Mercedes 230. want to push about 8 to 10 psi for now. Anyways if anyone wants to buy a New SPA turbo manifold for a 153 let me know!

I suggest Beater. But his compression is a bit high.

MBHD

Yes, The engine I'm putting together would not work with boost. but I have a few other blocks that may come to life someday. Just bogged down with two house remodels right now.

You could if it ran on E-85 or straight methanol.
Just a thought.

MBHD

I've built many Big and Small blocks with 14:1 compression and more that still used 400 HP of nitrous with no problems. It's all in the cam. If your just barely over what you think is safe, a cam swap can easily get you there with a turbo.

Why not inject it? The power level you want to make is well within what a TBI of off a BBC will support - and this eliminates all the issues with fuel distribution. Off angle approach - no more issues with floats.

Not sure if the holley TBI supports boost but the megaasquirt does - a bit more work but less $$.

I am sure if you help Beater get his first megasquirt project running (how long ago was that?) he would do more megasquirt set-ups.
Just my two cents.
It is a steep learning curve if you are not familiar with this type of systems.

I am sure it is easy to do , once, you learn how to or better to have someone show you how to get it all working.

I will venture to say, most guys here were not brought up with using computers could be wrong I guess.
Not saying we cant learn, it just seems a bit overwhelming I am sure.

My friend recently built a MegaSquirt V3.0.
He says it took him approx 20 HRS to build.
He also said he could have put 2 together @ the same time in about 22 HRS.

He built several of these MegaSquirts & I consider him a great tech on these types of EFI systems.
He can tune any EFI set-up, dyno tunes, all different system's.

We even tuned my 91 Syclones factory computer which is more difficult, burning chips.

Just saying, it's not easy, & I would rather pay $160 more for a built unit than for me to build one. But I understand if you have more time than money you would build it yourself.



MBHD

Agreed - these days - get a pre-built one and work on the install.

I can send an initial tune file for a TBI unit on a 250.

Just a note the last time I build a 3.0 main board it took 5 hours - going hard at it from start to ready to install. But I do electronics full time so not quite the same as someone new to board assembly/electronics.


There still is a learning curve to do, if someone has never done any computer work and or EFI tuning better if they buddy up with someone who has some experience. With the number of megasquirt installs out there this is not hard to find these days.

EFI-DIY, do you have a way of posting that tune for everyone to grab? Or could you send it to me?

I don't know if I'm going with a Megasquirt 2 or 3 yet, but I'm going to use a TBI regardless, non-turbo.

Yeah, my friend does not do circuit boards for a living, but he enjoys working on them, so not saying he was fast, I am sure he took his time building the board.

Just takes time & patience, can't whip one out in an hr.
Probably could if you build the boards for Megasquirt.

MBHD

I did not log my time but I am sure that I did not spend twenty hours on the actual build of my MS 2, GM adaptor, and the stem board combined. I am neither a computer guy nor a builder of electronic circuit boards but with good instructions and "support" from efi-diy it got done. My downfall was finding and setting up an affordable laptop that could run Windows and also access the internet from our Hughes satellite account. Learning Windows was another challenge. I began with Windows '98 and ended up several upgrades down the road, one that is no longer supported by the developer. I hate the constant "improvements" in this stuff.

When all was assembled I swapped out the stock ECM from my old '89 GMC and tried to run it on the MS. It ran as long as the starter circuit was hot but died as soon as I let it go. I got frustrated and hung it up. A couple of years later It dawned on me that I did not have a file loaded to run the GMC. By then I was too embarrassed and disinterested to go back to it. I'm the most ADD-HD dyslexic SOB you'll run into on this board. If I can get as far as I did you guys can walk right through this stuff. Someday I may run across the box full of this stuff and give it another shot knowing that what I have is now dinosaur crap.

Just how far would you have gone if EFI DIY did not help you any?

Just making a point, it is not easy if you are not familiar with this stuff.

MBHD

I doubt if I would have started without Marc's support but as far as putting the MS together it was no harder than putting a model car kit together. The instructions and on line help on the MS site are all you need. There were a few changes because I was using the GM adapter board so I could use a striped down junk yard GM wire harness.
Marc's style was a combo of offering to actually do some of the computer stuff if I would send it to him and jabs with a mental cattle prod. I did not send anything because I needed to do it. The hardest part was mastering the specialized vocabulary used by everyone involved but me. Next was learning to use Windows. Yes the learning curve was steep and I would have to learn it all again because it is a language not spoken in my circles. Several of the guys in our local chapter speak 4.2 now but not MS.

Maybe some day I'll see if the old '89 will still run and I'll try again. I'll download a file this time so the MS has something to work with besides the the initial injector squirts from the starter circuit. I have a "baby steps" plan still in place though it is dusty.

Well wound up buying a super low mile m90 supercharger. its probably a little big, but I will turn it slower, so it should make less heat. trying to decide if I should stick with the cam I have or maybe go a little bigger. The cam I have is a mild cam 204 at .050, .441 lift, 112 lobe sep. was thinking of going with a comp 260 high energy 212 at .050 .489 lift on a 110 lobe sep.

I would go w/a larger camshaft, but not one w/a 110 lobe sep.

114-116 lobe separation I would go with.

You do not need to get from off the shelf Comp Cam, they will grind what ever specs you want.


MBHD

Hi, I'm Jerry4. I have a Mercruiser 4 cyl, 181 ci. I'm installing it in a Model A pickup and have a problem with width. First problem is the alternator, I'm looking into a smaller unit build by Denso. Should be here by next week.