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B230F LH3.1 budget na build

Shoestring, could you share what diameter pipes you've chosen and what your power goals are? If you could share your calculations too, that would be excellent. Another reason I'm interested in standalone is because everyone talks about ecu failures. I know it's easy enough to buy a spare and keep it around, but it still bothers me.

We have roughly the same size feet it seems. And no, I'm not applying enough brake. It's hardest when I'm trying to brake gently before a turn and match the revs downshifting into 2nd. It's not too hard to mash the brakes and stab the gas (for a whole second) to get the revs up, but it still feels pretty awkward. Maybe I just need more practice.

klr, that's about how I've been heel-toeing. I actually don't remember if this is part of the problem, but I find it a bit funny how the gas pedal is on a pivot. It's actually really nice for normal gas pedal operation.

So you switched to the kg type 3 header? The non-linear steps up in pipe cross-sectional area seem counter-intuitive to me. The simons and the kg type 4 have relatively linear steps in cross-sectional area. The simons header (URL="https://www.skandix.de/en/spare-parts/exhaust/manifold/fan-type-manifold-simons/1020705/"]https://www.skandix.de/en/spare-parts/exhaust/manifold/fan-type-manifold-simons/1020705/[/URL]) steps are 45-51-63.05 which is comparable to the kg type 4 header.

It's not just that I want more sound from the exhaust, but the header really changes the quality of the sound in a way that I really love. I also really like the look of a wrapped header under the engine bay. I'm a big fan of simons exhaust systems as well. I had one on my '99 V70 T5 and it really sounded incredible. Not loud or boomy, just a really healthy sounding exhaust note.

I recently deleted the air box thermostat and just plugged the tube with a pipe end cap. The air pickup hose seems to be the same diameter as the hose going to the manifold. Is this really a restriction?

I'll have to look more into the 940 fan conversion and I'll definitely go for the flat flywheel when I do the clutch.
 
ECU failures are not that common, really, but a more modern stand alone setup is going to be easier to fine tune and be more responsive as well.

Yes, I had my Type 1 header modified with shorter secondary pipes(Erland Cox's recommendation) that matched the Type 3's 51mm secondary diameters. I do NOT recommend this for your car. My car's goals are 160+whp with larger valves, port work and a larger camshaft with higher compression. The Type 1 would likely be sufficient for you and may not make any difference power wise. The primary pipes may be a bit larger than Pipemax or similar may calculate as being optimal for such a mild build, but at least the exhaust flow won't run into a wall as it exits the head. The Simons header matches the Type 3, not the Type 4 which has even larger secondaries. It is more of a racing header, like the Type 3 and Type 4. Here's a link to the KGT stuff, they're quite reasonably priced excluding shipping. You could also go with the Type 2 and then you can have your full 2.5" system and a little room to grow if you ever decided to take a little more off the head with some port work and a larger camshaft.

https://www.kgtrimning.org/tuning-special/b23b230b234/typ1-240.html

There's also this option with 42, 48 and 63mm piping: https://shop.klracing.se/sv/artiklar/extraktoirgrenror-volvo-240-8v-4-2-1.html

Speaking of these headers, wrapping or ceramic coating one of these is a good idea for a street car because it'll help keep the exhaust hot for catalytic converter efficiency. I can't pass the local emissions testing even with an H cam in my current setup and part of it is because my race cat cools down too much at idle. I want to get the header coated at some point to retain heat for that.

The stock intake is absolutely a restriction, remove that cap and the entire flapper thing if you didn't when you pulled the t-stat and route pre-heat hose to cool air.
 
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Mill the head 2 mm, GT6 cam and 45dcoe's, It'll run only right at full throttle and above 3,5k but man what was that a fun car to drive! :lol:
 
I looked at where the inlet pipe goes through the radiator/headlight wall and yeah, it necks down into this cute little 2" dia chimney. Is this why the induction noise sounds more like a truck than a car? It's all whoosh and no grunt.

Maybe I should feel bad about this, but I was considering losing the cat. I'm in texas and the car is more than 25 years old, so there is no emissions testing whatsoever.

I think I would like to go kinda crazy on a full n/a build in the future, so I may end up getting a ridiculous header anyway...

How come more people don't do a 16v na build? I see people complaining about complexity, but how hard could it be especially if the head flows that much better? The only major thing I can tell is that you have limited clearance due to the brake booster.
 
People don't do the 16V NA build, or even many 8V NA builds, because it isn't as easy to do. Custom intake manifold as opposed to just a cam swap, etc.. More expensive head work when you do it, etc.. It can make more power, much easier, though. I don't remember our 16V being faster than our more built up 8V to be honest, but we never had it on a dyno to be certain.
 
I think a 16V head could support quite a bit of power, properly executed. I'm not saying 400hp, but I'd think 250-275 is not out of the question and probably not too difficult.
 
I'm doing the 2-step tri-y, but with 1.625" and 1.75" tubes (41x44mm), leaning toward the more hp driven of the collectors. The desire is to yes, get more power, but also to stretch the rpm band out some couple hundred. Currently the engine peaks at 5644, and it would be favorable to peak a little later by a couple hundred.

DdYsGPb.png


We currently make 144 whp. The goal is, well, more. If we see double digit gains, that would be awesome. If we see 5 peak hp but the rpm curve stretches out 3-4-500 rpm, that would be WICKED.

Who knows? Maybe it's just end up being a huge waste of time and money. That possibility exists too.

PS we made 120whp with a head skimmed 1mm, a thin Cometic head gasket, a D cam, no cat, and a glasspack. With an M47. With an AW70 it probably would have been closer to 70. :-P
 
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Pipemax there shows you're targeting only 5744rpm for the peak, no? Don't you want it to say 5844rpm, or so?

Those pipes just sound awfully small. What are the stock manifold's runner diameters, approximately? And the secondaries?
 
As it sits it peaks at 5644. I added the 100 rpm as a target, some of this program is somewhat iterative. I'm not certain what the stock tubing size is. I can tell you that the 408 SBC in my Camaro made over 360 whp on 1.625" tubes, so I would be shocked if they were restrictive here. If anything I was concerned these might be a bit large.
 
I wish i could remember how small the pipes were on the RSI header they did up, They may have been even smaller than that but I can't confirm. Maybe I'll see if Jonathan remembers.

What happens when you bump up the peak rpm target another 100? :)
 
These guys have you well taken care of. I just wanted to drop this here to let you know what some mild work does. I kept my 93 wagon n/a. I modified the air box for two air intakes, installed a enem V15 cam, and a chipped ezk. Along with a Simons sport exhaust. My car is a five speed so that combo has worked well for a daily.

Headwork, a lighter flywheel, and a better intake like the kjet would be helpful. I am not going to go any higher compression because a turbo is going to happen at some point. In the meantime this is enough performance to make it a good daily. The tall rear axle keeps the rpms low on the highway. This has been a good setup for several years now.
 
I wish i could remember how small the pipes were on the RSI header they did up, They may have been even smaller than that but I can't confirm. Maybe I'll see if Jonathan remembers.

What happens when you bump up the peak rpm target another 100? :)

Well lemme check it out...
 
Well lemme check it out...
Bump.

I mean, the small runners may not be restrictive for the amount of flow your engine is puting out, BUT, first the exhaust flow must run into the wall that is the flange for the smaller opening. You don't want your flow to run into walls, it's just not good! :)
 
Aha! I see you...

I know I checked this out, and I think the tube lengths changed by like 0.250" or something like that. Basically irrelevant based on my manufacturing capabilities.

I actually think this may be complete and ready for me to pick up this weekend. Only took me about 7 years to build.

Hope it was worth it.
 
Ha! I hope so as well!!! An intake manifold is going to make a larger difference, though!
 
Well, you're at peak flow for the intake already, but the factory exhaust manifold can support more power than what you're doing already. Sure, a properly designed header should be able to make more power than stock, but it is not as much of a restriction as the B230F intake manifold.

Erland Cox when discussing our next engine with him and the C2 camshaft:
Erland said:
I use pump gas, it is called 98 but it is not calculated like yours so it is more like 95 in the US.

I run the pistons 0,5mm above deck with a 1,3mm gasket then I mill the head 3mm for 13:1 + compression.

I want over 16 bar in a compression test.

With your restrictor intake you should not have any problems doing that.

The stock exhaust is OK, much better than the intake.

It helps to play with the down pipe, they are different for GLT:s with more hp.

You will probably need an oil cooler. The water cooled one from a 940 turbo should probably be enough.
Our "restrictor intake" he's referring to is the early/K-jet intake manifold with a 90? elbow to a 960 throttle body. He highly recommends getting rid of the lower throttle body opening and relocating the throttle body to the front, like this example of his work in progress I got many years ago.

A previous excerpt from our emails:
Erland said:
What are the rules, do you have to run a stock manifold?

I am doing a group A B21 turbo with 405 head, stock valves and F intake.

Some minor porting gave me 205 CFM at 12mm.

With the F intake in place I have 160 CFM.

With only runner that is ported at injector 185 CFM.

So I have some figuring out to do.

The E manifold is good but you have to move the throttle to the front of it.

You kill the flow with the expansion that you get with the stock throttle position.
 

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Lol, you don’t. You’re just curious “how much better”. As are everyone else. When I get around to changing the intake on my car, it won’t be apples to apples anyway, because the throttle body will also increase in size.
 
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