Inliners International Forums General Discussion Engines First timer

Ummm, I thought that's what I said. All the combos with stock cam are about the same. But the cam makes the difference, even with the stock valves. But more valve is even better.

To help clear up some stuff.
The lumps have been proven to make more power.
So do valve enlargements and larger cams.
A 292 engine with stock cam and head was ran, then was tested again with only a lump added. Basically no change in power was recorded.
Once a larger valve was used, the power went up.

Another test was done with the 1.94 valved head to remove the lump. The power went down. This confirmed the lump really does add power with larger valves.

All the 250 and 292 Dyno tests were performed by me.

Here is a page from my website that shows some dyno runs performed on the 292.
http://www.12bolt.com/65279inline-cylinder-head-flow65279.html

Since this thread was turned into a science project I'll fill in for you. lol!

With the lump ports and a stock head it was noticed that the engine ran smoother. Mainly because there's smoother air flow now.
Add a cam and you get a 30 hp increase.
Now, Add flat top pistons, a good cam let's say around .499 lift, 1.86 intake valves and 1.60 exhaust valves, 4 barrel and headers, and you'd be looking at over 100 hp over stock. Tom Lowe has some neat 250 builds that haul.

I have a 230, and deliberately wanted to keep it as such, and see what it could do. Cam, zero deck, head work, lumps, compression bump, HEI.... so far I'm not impressed at all. The last things on the list are 2bbl and headers. If those don't really wake it up, then I'm calling it quits and licking my $3000 wounds, may sell the piece of sh*t. LOL.

Well if your still running the stock Intake and Exhaust. Well there is one of your Biggest defaults. in your Build.

Why a 2 barrel? lol And why are you expecting 500 hp out of 230 cubic inches? If anything stroke it to a 250 with a 250 crank and rods and you'll get over 300 hp. OR you could turbo it. But hell...If I had a little 230 in a 3500+ pound car I wouldn't be expecting a whole lot.

Twisted: this build is designed with bigger intake/carb /exhaust in mind from the get-go, I'm just not there yet. To get the basics sorted out (and the rest of the car street legal and driving) I wanted to start with stock intake and exhaust, fully aware they would be big bottle necks. Still, I expected more from this stage.

TJ: The 2bbl is an intermediate solution, I happen to have a couple plus now I have a spare stock intake to modify. Basically a free test to see if a bigger carb/more cfm would make a clear difference. If it doesn't get ANY better, then I have no justification to spend money on a 4bbl and intake for it.

I am not expecting 500 horses, lol. I am expecting "a result" from each mod, I don't have any real world expectations per se, never built one of these before. I have built several other engines, more than I can count. This one interests me, one reason being that for a "Huge" displacement engine (by my european 4-cylinder background standards), this lump made NO power to speak of in stock form. So I wanted to see how much more I could make, without changing displacement or force feeding it. It had to be choked down by design. So I/we all here, are removing the bottle necks, and letting it breathe.

I COULD do all kinds of big power things to it, and for the money spent, I could have a REAL nice V8 in it making 3 times more power than this thing ever will. In maybe two weekends. It's not about that for me.

What I learn from this project, I might one day apply to a 292. If I learn that it's pointless to try to make more NA power with these engines, then I will just go turbo and call it done. Or turbo and add some of the tweaks and mods that seemed to work well in this project, pick the best ones.

I also know that a 3 speed trans would help acceleration tremendously and let the engine stay in the power band better. Also a higher stall converter would help. But if I did those NOW, I could no longer compare my engine performance to what it was before. It wouldn't be comparable because the gearing would have changed, for example. I want to know what this engine could do, with EVERYTHING else being stock.

This in mind... I'm not impressed yet But I'm not done either. Now more than anything, I need TIME to work on it. It seems to be hard to find.

And yea, a 4 door 1970 Nova will never be a quick car. I have no rational explanation as to why I am doing any of this. But I don't need to explain that to you guys

And going from 230 to 250 is really not a very big improvement, "you'd get 300hp out of it" is a stretch, by that logic alone I should just as easily get around 275hp out of the 230....

With a 1.94 intake 1.60 exhaust lump port head. Flat top pistons. .550 lift cam. 4 barrel, headers, hei. Possibly a head shave and 0 deck a .040 over 250 made 320 hp and 275 torque.
My 292 with a 1.94 lump port head and 1.60 exhaust valves with ross lp pitons, .040 over bore, 0 decked, .030 head shave. Fairly mild .499 lift cam, 4 barrel, headers, hei is expected to make 310 hp and 330+ torque judging off of Very similar builds.
There's no replacement for displacement. Over bore and stroking out that 230 would help for sure. V8's bore me unless they are over 500 cubic inches. lol!

Yeah, that's what I remembered. Adding lumps and valves together gives the power.

The key part of my build is to keep it a 230, not stroke or overbore it. Keeping it the same size. I have a lead and a plan slowly taking shape for a 292. I doubt a 230 would *need* bigger valves to run ok. Comparing it to a modified 292 makes no sense. That's a helluva lot bigger air pump with the same head on top. I'm comparing mine to what it was, a 230.

My point was that cheap power is to add cubic inches. But your wanting stock size to experiment with. Also my other point was that because your dealing with a very Small amount of cubic inches I wouldn't be expecting a whole lot. Unless you put it in a 1500 pound roadster or something light, then you might see that engine wake up a bit more. Keep in mind the 230,250,292 all had the same bore size. More air flow doesn't hurt. The 1.72 intake is rather restrictive, not mentioning that head bolt boss. And I'm not Comparing it to a 292, I'm Saying that adding cubic inches Helps. lol Hence why I mentioned stroking it to a 250.

You don't have to also add bigger valves with the lumps, a bigger cam also made more power with lumps and stock valves by adding more cam as well according to the dyno results, 31 HP more to be exact. Sure adding bigger valves can too but so did just adding a bigger cam with the lumps.

Even though there isn't much cubic inch difference between the 230 and the 250, it still isn't going to have the low end torque and power you will get with a 250 regardless of the mods you do. The stroke difference makes a huge difference in smaller engines.

First.... 230 is not "Small" cubic inches by any means, LOL. That's 3.8 liters, which is HUMONGOUS by European standards. I can easily make 200HP out of a 2 liter 4 cylinder. 100hp per liter of displacement has been achieved decades ago and is now more or less a standard. In contrast.... 3.8 liters should EASILY make 300-380hp.... right?
My 2 liter 1937-based design VW beetle is 2 liters and almost hitting 200hp. USA has always made horsepower primarily with displacement, not focusing on breathing, flow, and efficiency. I wanted to optimize the 230, to see what it could do. Logic says, there's gotta be a lot of reserve power hiding in 3.8 liters of displacement, which is a LOT of displacement. The design is just very, very inefficient. Choked down by many things.

The head is already ported and lumped so it is about as good as it can get with reasonable amount of work. Not sure everyone agrees lump kit is reasonable either. Bigger valves could give me a little more power, but I find it hard to believe that the difference could be as dramatic as some posts here are trying to make you think they do.. I have done many engines with larger valves, and many with stock valves. At THIS mild level of tune, I don't see them being a major bottleneck. It is not the secret key to unlimited power.

Don't get me wrong, I love working on this piece of stone age cast iron... and I get a tremendous amount of satisfaction from learning. Even the hard lessons are valuable and interesting.
I know there is more power under one rock or another, I just want to keep flipping rocks over to find them. At the end it will be a combination of many things like you said, I doubt there's any ONE thing that would make me think all the other mods were useless and I should have only done THIS and ignored the rest.

So far the most noticeable difference has probably been the HEI distributor. I was going to go with an MSD box and already had a pertronix conversion in the old stock distributor (which steadied the timing tremendously), but I knew I had a worn distributor... with a curve best suited for farm equipment.


I can hear a positive difference in the exhaust note, its starting to sound more like the tiny 4 bangers when tuned up, the pressure is there, but the power (flow, breathing ability) is not. There is a narrow rpm band and speed combo where the car really performs well, but it doesn't take long to fall out of the optimum window. Its like it chokes just as it starts to feel like it wants to go fast.
Mixture is set a little rich but its consistent all the way through. IF THIS WAS one of those engines I know better, I would definitely do induction and exhaust next... And that is the plan. Just looking at the numbers it seems way under carbed. At first start with a 2bbl on a stock, modified intake, and Langdon headers, dual pipes. Again I am expecting a noticeable difference, but we'll see. I don't want to jump straight to a 4bbl, the "known good" solution. Then I wouldn't learn anything about fitting a 2bbl on it.
As it is, it's very driveable and I am enjoying driving it again. Its soothing, relaxing, and the exhaust pipe plays a tune much more satisfying than the radio ever could

If it was about money, I would have put that 350V8 in it 2000 bucks ago and have twice the power. But I don't want to be like every other Nova owner out there. I specifically do not want a V8 engine in it.


...I want the fire breathing, gut-thumping, earth-moving, tire-roasting V8 monster motor in my..... 1989 Volvo 740.

That's good, I felt a sense of discouragement in your earlier posts. One good sense of accomplishment you can always have is knowing you took an under dog of an engine design and improved it significantly over what it was originally. I think that's what satisfaction most people get that mess with these engines. Keep tinkering away and make sure to post your triumphs as well as the so-so gains you have.

I get discouraged or disappointed sometimes, yes. Then I turn my attention to other cars. I am down to 7. I mentioned my Jeep earlier.... after getting the Nova back on the road, I shifted focus on the Jeep 4.0 and made it better.... with a few previously unheard-of mods: Cam, port work, compression, chip tuning..... :P It responded pretty well to what was a very mild build. It feels like it should have been made that way from the factory, like I managed to unleash the last few horses I knew were hiding in there with just some basic optimizations. Sound familiar?

Here's the Jeep 4.0 exhaust port/intake port......



My jaw dropped when I saw the exhaust port size.

The new cam has more duration increase for the exhaust, than it does for the intake. Both have a little more, plus more lift. It was also ground on a wider LS angle to maintain stock-like vacuum signal, because this engine management relies on MAP sensor data for controlling everything. It's a custom designed cam to work around these limitations without having a Check Engine light come on... very happy with it.

Add more compression, BANKS power tune programming and another 2 degrees extra ignition advance throughout the rpm range, and 94 octane fuel... God I wish the Nova made this much power.

When it comes to the HF engine stand bolts do i replace all of them or just the bolts that attatch the engine to the mounting plate?

I only got new bolts for the engine mounting, I got bolts long enough that they would go all the way through the flange so I could put a washer and a nut on the back side (engine side) so even if the bolt holes stripped, the nut would catch the engine. Of course with mild torque on the nuts, the bolts wouldn't strip to begin with.

Be sure to go with 8 grade bolts!

After rereading some of these post i starting wondering on how my mpg would be like if i did the lump port, offy with a 4 barrel carb, bigger intake/exhaust valves, langdon headers, and 307 flat top pistons? After all i plan one making this my daily driver.

I forgot to add the cam

If I were you and I was building a daily driver I'd invest in EFI before go-fast stuff.

https://holley.com/products/fuel_systems/fuel_injection/sniper_efi/

Add in an electric fuel pump and return line and you're good to go. That'll make starting a lot easier, it'll run a lot better and gas mileage should go up. This would require an intake, however.

After that I'd look into a 200r4 so you gain some gears if running auto. That'd be good for a couple more MPG and a bit more pick-up.

Mine: 68 Camaro with a 250, power glide, Holley 390 cfm carb, offy intake, langdon headers, 2.5" exhaust, mild cam, HEI, and electric fan. Haven't touched the head yet. Only getting about 15 mpg but I'm not light with my right foot and it's running rich (not too rich. Just a bit.).

I don't own a 1970 four door Nova for the MPG


Edit:

Being that I'm sticking with the small inline 6, I don't own it for the performance either.

Mine looks like crap and I never liked Novas to begin with, so I don't own it for the looks.

Mine has almost no monetary value, so it's not like I own it for the financial investment point of view either.

I bought it for my ex who *had to* have it, then she whined about it being too hard to steer and it ended up being my daily driver in Florida, with no AC. When we got divorced after she cheated on me and left me and took the kids several states away, she let me choose one of two cars (I bought her 5 cars and one way or another she ruined them all): A very nice 2000 Ford minivan or the Nova. That's all I have left of my marriage, a sore reminder of betrayal. So no, I really don't own it for sentimental reasons and value.

The Nova is on the road and the minivan, along with all her other cars to date, are not. So yea.... maybe THAT is why I own it She has told me not to drive it when I come pick up the kids for the weekend. Sore subject I guess.
She remarried 3 weeks after our divorce was finalized in 2010 and he bought her a same year Malibu as my Nova. Same 230 engine, same 2 speed powerglide. It has not run since they got it 3-4 years ago. HA! WINNING! I'm keeping the damn Nova. If only to rub it in.

Real Cheap way to get better MPG is Tom Lowe's 3 barrel carb modification.

I understand that if I want more hp I'm going to get low mgp but I dont want a 250 with 10mgp because if thats the case I might as well stick with a v8

I would think.... without doing any real life testing yet with this engine, that if you make the engine more efficient, like have higher compression extracting more power from the same amount of fuel, then you should get better mpg IF you keep your foot out of it and don't USE the extra power, just drive as you did before. In some cases though, depending on gearing, driving faster saves fuel. Too many variables to give a definite answer.

Tom Lowe's 3 barrel mod got him 22 mpg out of his 250 pulling a 4000 pound chevelle wagon down the road at 75 with 2.56 rear end gears and a non-od 5 speed.

Let's chat a bit about engine design. There is no naturally aspirated, non-crossflow engines make 100hp per litre that are anywhere close to streetable. Looking at an example European engine of similar era to the 194/230/250: the English Ford 105E (which was very competitive in its day) made 39hp/litre stock high compression, 37hp/litre in regular gas verion - about the same specific output of a stock 230. In full race (totally unstreetable) the non-crossflow 105E hit 100hp/litre. It was not until the crossflow versions came that approaching a 100hp/litre in a streetable version was practical. The 105E also has the advantage of a very short stroke - the same bore was used for 1.0 to 1.6 litre versions of the "Kent" engine family - the most common USA application being the 1.6l Pinto. The last version of the Kent engine with a dohc 4 valve per cylinder head and turbo charged made over 800 hp in race trim.

A well designed 2 valve crossflow head is worth 25 to 50 % increase in specific output over a 2 valve non-crossflow head. (note: the VW flat four has crossflow heads)

It is educational to take a look at what the Australians did with the big in-line six cylinder engines, especially Ford: non-crossflow, then crossflow, then overhead cam..... and Chrysler - the Hemi head (crossflow) slant six.

To get more than about 60hp/litre naturally aspirated in streetable trim, you need a crossflow head. If you start with a dohc 4 valve per cylinder head, for example Vortec 4200, you are at 69hp/litre before you even start modifying, and approaching 100hp/litre naturally aspirated in streetable trim is not difficult - even with the very long stroke.

Bottom line, when discussing specific output, stay with the same type of head: non-crossflow vs non-crossflow, and the 194/230/250/292 is quite competitive.

I finally was able to start tearing down my engine and took the bolt bosses out the head. What would be better an electronic die grinder or a pneumatic one? I would have to buy it either way

Hi Nigel.
Interested to read your comments,particularly regarding what we in Australia did with the six cylinder engines.

Chrysler Slant Six and the Chrysler "Hemi" six are totally different engines and no major components interchange.
You will be familiar with the trusty Slant engine and obviously it did not have a cross flow head.
Neither did the Australian built Hemi.
I drove these things when they were new,middle 1960's to the late 70's.

Here is one of the Hemis in full flight on the dyno. No crossflow.
And one of my old Slant.


CLICK HERE

CLICK AGAIN

regards,Rod.