MAGK944

Now are we talking street or track engines here? That Broadfoot is a track engine, there are no options for tracking an LS1 944 unless you were grandfathered in under GTS Challenge or something.

For a street LS1 here are the base prices:

#89017548 2001-2002 Camaro (LS1) 5.7 Liter 350CI New Goodwrench Engine $3,272.91
#10465385 Gen III/Gen IV Starter 10465385 $350.06
#19155066 Accessory Drive (with air) LS1,LS6 $860.93
SubTotal $4,483.90

Basic Conversion Components as listed on Renegade $2100
SubTotal $6,583.90

Other necessary upgrades will set you back about $3000 for an na base chassis and $1000 for a turbo base chassis.
Total Approx $9,600 to convert an na to LS-1 properly and using a crate engine with warranty and all new parts.

Calmchaos

Ok, thanks.
I was just wondering, not trying to be a smartass.

67King

An average is, by its mere definition, linear. I see what you were trying to do, and my point isn't that the guess is bad, so much as it is uneducated. You are taking a confined space of two points, throwing in a fudge factor, and extrapolating out 8 times beyond the range of your data! Draw it out on a piece of graph paper. Extrapolating from a bunch of data points to a very small range beyond the upper limit isn't so bad. But holy cow, taking just two points, and extrapolating that much is VERY flawed. I really don't think people here understand how much of a task 200 horsepower is on this engine.

Work performed per BTU isn't clear. Not trying to play a semantics game, but it could be indicated, or it could be brake. You are talking about brake. Brake is indicated power minus mechanical losses. Problem is, brake anthing has two components - thermal and mechanical. The relationship is complex. Thermal is multiplicative, in that a change to an input is multiplied. But, fuel efficienty is "BSFC," or brake specific fuel consumption. Your range is quite a bit off, though. The engines operate in a broad range, with the most common refernce being the World Wide Mapping Point - 1500 RPM, 2.62 (38 PSI) Bar loaded (that's a BMEP term). That is so low in the RPM range that the engine is 94% mechanically efficient. However, that number is calculated AFTER the thermal efficiency losses are factored in. And as I said, those can be in the 60% range. 50% is more likely the case with most production engines. Higher CR's, thermal coatings, etc. all help move it upwards in racing applications. Most "overall" efficiencies I read are in the neighborhood of 30%. In all likelihood, that considers driveline losses, as well as engine losses. And it also is probably not measured at the engine's peak efficiency point.

The reason I'm bringing up all of this stuff is that it confounds any assumptions you try to make with a compression ratio change. That is an exponential function. So, in trying to understand what kind of benefit you'll see with a compression ratio change, you have three operations.
1. Exponential (this gives you the percent benefit change to thermal efficiency)
2. Multiplicative (this converts thermal efficiency into indicated power)
3. Subtraction (converts indicated power into brake power)

Anyway, I'm not trying to play games of semantics and what-not. And I'm not trying to sound like an engineer. But again, when you are talking about some seriously stretch goals, this stuff all matters. And honestly, it can be helpful for the run of the mill "hot rodder" when looking at parts. Claims such as "frees up 25 horsepower" are typically crap. Understanding this stuff can help you flag that, and help you spend your money more wisely, as improving thermal efficiency goes a lot farther than adding some "low friction" stuff to an engine.

MAGK944

Your welcome, I didn't take it as a smart *** comment.

67King

Its a little different with turbos. I'd feel comfortable with about 9.0:1, but not really any higher. But, a turbo 16V? Sign me up!

Lorax

I sold the 16v 2.5L motor and I am now looking for a S2 motor to boost. If i have my way i'm going to use forged turbo rods (Very cheap) and stock pistons. ~10:1 and 15psi, but this is running on e-85 and of course that is a game changer.

Total cost under 4k and probably well over 400rwhp even without cranking up the boost. A very nice powerband too since with the e-85 motor you don't have to lower the compression and lose low end power.

Then again I have also considered parting my car recently.

Lorax

Yes you hit it on the head that it was a "Butt dyno" guess bases upon a small increment, but since that it what I had to work with it is what I used. Although I don't think the guess is that far off. Those engines above aren't even using that high of a compression to reach 200hp (of course with slightly larger displacement) but using a fuel with an octane of ~110 i don't see why it's not possibly on a 2.5

Lorax

E-85 is could allow the limits to be pushed even further compared to that crappy old 100 octane junk

Steven S

So I just picked up my first p-car, an '88 924S, for my next race car after racing Hondas and formula cars for years.

Standard-issue, I'll take as much weight and drag out of the thing as I can sniff out. Power-wise, the 8V's no better than the Hondas I just got out of. This '24S came without recent service records, so I'll be going after the usual timing chain/water pump routine. I hope that the cylinder bores are okay (I've just turned it over after it's been sitting for a year), but I wonder how far this block can be bored out. Anybody know?

I'm keeping potential VAG-family engine swaps on my radar, but I'm not interested in truck motors or boost leaks.

For season 1, I expect to run chipped, with headers, a knifed crank and light flywheel. I gather it's no big advantage to run intake mods with the standard airflow metering system, but I wonder whether head work is worthwhile until season 2, when I get to a stand-alone system with ITB's. Advice?

I don't know whether it's realistic to upgrade to a 16V head, but it's probably cheaper both in the short and long runs to source a hot cam for the 8V and port the thing anyhow. Definitely the plan in season 2, if not in season 1.

How much power is there in deleting the balance shaft?

As for dry-sump, if they all cost as much as Broadfoot's, I'll run an accusump and oilpan baffles, thanks.

V2Rocket

we have not seen any real benefit power-wise to deleting balance shafts. however they would be on my list of things to delete because they are very heavy (gotta be 20lbs+) and already spin at twice engine speed, and at the speeds needed to get 200HP theres alot of potential for damage.

also the balance belt is known to sometimes break and the flying piece of rubber can damage or break the timing belt also. and at 7500RPM valves dont last very long at all against a flat-topped piston when the tb breaks

86 951 Driver

How bad would the car vibrate without the balance shafts and weights?

V2Rocket

balance shafts only come into play somewhere around 3000RPM.

if you only took the shafts off, nothing else, i imagine it would vibrate considerably more. people have had problems with cracking oil pickup tubes due to this vibration however which is why i recommended a drysump.

the vibration would be reduced by lightening and balancing all the internal rotating parts, namely the crank

86 951 Driver

So the cranks and rods most likely if they were blueprinted and balanced the motor wouldn't shake at all or if it did about as much as it does now? These engine just cost so much to build up. They cost double of what your standard v8 does. Its just ridiculous. I mean port out the head a little bit have a MAF instead of the AFM, port match the manifold, and you should be at about 180 hp. at the crank. Build up the bottom end with higher compression and now your about 200 hp. I don't know why its so hard for this to happen for under 2 grand?

Lorax

No... you won't have 180hp but go ahead and do it and tell us the results. This isn't a honda. Even I know that while 200bhp isn't impossible it is expensive

As for balance shafts... the vibration isn't noticeable on a stripped out track car. If you lighten the internals they lose some effectiveness anyway.

86 951 Driver

I'm not trying to treat it like a honda. I just don't understand what makes this motor different than any other 4 storke ever made. I understand that this motor is about on edge, but in reality there is no way it is. If I had money to do a rebuild period I would try to get more power out of this engine. N/A is just not the way to go with these motors unless its a 968 or 944 s2. It needs forced induction with a custom ground cam. Thats where the power is.