i have a question has anyone built a reputable n/a car other than the skwirl cause i really like the idea of an all motor cavy ld9 but was wandering how hard and costly it would be

Karo/Todd. It takes much more work/money to get decent power NA.




fortune cookie say: better a delay than a disaster

N/A power is more respectable.. but much more expensive where as boost is comparitivly cheaper with higher gains ..peronsally i went NA..not many do..weigh your decision carefully

As mentioned already, Karo. I don't remember reading what he ran all-motor but I know that even without spray he had a HELL of a beast. Others here and there have managed solid 13 second runs N/A with the LD9 - good driving is the key to getting the most out of it. Of course there's been many others who have essentially "gone N/A" by basically doing the usual intake and full exhaust, maybe with secret cams or HO intake manifold swap, but stopped short of the really intensive (and more expensive) sorts of mods that give you even more increased power.

Personally my plans for my car, if I have the money for it, are as follows (sort of the standard plan for good N/A power with the LD9 really): intake, HO intake manifold, P&P head, stage 2 cams (LZM or JBP...not secret cams), 10.5:1 compression forged pistons, forged rods, 2.3 oil pump swap, pulleys, lightweight flywheel, header, 2.5" exhaust, and HP Tuners. Others get into using more of the HO Quad 4 parts (086 head, 2.6 stroker, just to name a few...) While specific numbers aren't really my cup of tea (I'm more interested in simply making the car faster and more fun to drive than shooting for an exact number), I'm guessing/hoping that those mods would put me close to the 200 whp mark N/A. That should (if the driver mod is up to par) put the car into the 13s pretty easily. Then...at that point, if I feel the desire, I may add a direct port 100 shot and have some real fun. That's a nice thing about a solid N/A build - you can get decent power out of it without spray, then, as long as you've used good parts and tune well, you can spray and make huge power for the track (...or wherever you want it).

And saying that N/A power is much more expensive...well, yes, and no. To get the most power N/A you really need raised compression (a rebuild), cams, and a P&P. Thing is, most everyone who goes with boost ends up with those exact things themselves...plus the cost of whatever power adder they used. You don't need to rebuild before boosting, but how many people boost their stock motor and then drive it for years without ever ending up having something go *pop* and then putting money into a rebuild. And...how much power can you get out of the stock motor without rebuilding it? About as much as you can get going N/A and rebuilding it (of course then, you can go with higher boost and reach higher power levels, but you're up in cost now...to continue adding power to an N/A car you can always go with nitrous at that point, and $800 or so will get you pretty far in the nitrous game). As far as cams, a lot of people go with the secret cams which aren't going to add a whole lot of power, but also cost like $100-125, and that's a drop in the bucket compared to the costs of a lot of these other mods - you can't even buy a header for that much really. P&P...it's my understanding that if you have the patience and probably a spare head, you can do it yourself and save yourself some money. Of course your results may or may not equal one done professionally, but many people do it.

Sorry to turn this into a novel, but another thought - you can go with N/A but rebuild with like 9.5:1 compression and then still boost the engine without too much trouble, especially if you supercharge it, if you change your mind down the road. At that point you'd have a nice solid bottom end to throw 6-7 psi at and not have to worry too much, unless your tune really got screwed.

I gotta admit, I was exactly the same way when deciding on what route to travel down with my car. I was 110% in favor of N/A, and nobody could tell me otherwise. That's it, that's all, and that was how it was going to be.

BUT, my view is similar to that of Marcus'. In some sense, when you think about it, if you look at any well-constructed turbo car, with the exception of certain sub-selections, those cars with the turbos taken off are basically built N/A cars. My motor, as it sits right now, aside from the cams more or less, would have been pretty much the motor I would have ended up with had I gone solely N/A. But now I've got that motor with a turbo stuffing air down it's throat to boot.

Commenting then on the price scenario, yeah, I wouldn't have had to go to this extreme to have a relatively reliable turbo that turned out moderate PSI, but if you are going to go all out, then a turbo setup is essentially the cost of your N/A build, plus all the turbo modifications and necessary parts/accessories tacked on to that price.

With all of that said, my opinion would be somewhat "up in the air":

If you're solely looking for a big increase in speed, go with a moderate turbo setup.
If having a solid all out build is more important than just speed, then go N/A.
If you're looking for an ass-kicker, then just as Marcus stated in the above, concentrate on the N/A build, but make choices with that future turbo addition in mind.

N/A is respectable, and always and forever will be (I wish I could afford another car than ran on a built N/A setup), but in my opinion, once you've got that turbo in your car, you're going to wish you had a turbo on everything you own... LOL

Well, normally if you go boost, you don't really want to increase the compression ratio since that will probably cause the mixture to ignite before spark due to the high heat. Adding an intercooler would help a lot, but sticking with a decently safe compression ratio will prevent many problems.

Also, on another note, if you add a turbo, you usually HAVE to go through and upgrade the whole fuel system since stock is insufficient for decent boost, and then like it was said above, you will still gain performance gains if you do everything you normally would to a N/A engine to a boosted engine. As with many things in here, it all depends on what you want to put into it and what you want out of it.

Robert Freeman wrote:Well, normally if you go boost, you don't really want to increase the compression ratio since that will probably cause the mixture to ignite before spark due to the high heat. Adding an intercooler would help a lot, but sticking with a decently safe compression ratio will prevent many problems.

While it's true that higher compression is less safe for boost, I was suggesting that if you're building N/A but considering boost you go with a CR of like 9.5:1. That's not that high, in fact, that would be lowered compression for an Ecotec (and I believe stock compression for an LD9). Ideally, yes, if you're going to run high boost, you want something more like 8.5:1-9:1 range, but 9.5:1 is by no means unmanageable with a good tune and reliable setup.

Since you guys seem to know alot about this topic..... I was thinking of putting in 10.0:1 pistons into my LD9. I am putting in Eagle Rods, new valves and a P & P. I was thinking about the secret cams...where can i find the LZM or JBP cams? Now after I put all of that in how much boost do you think I will be able to run? I will also be putting in ARP head studs. Would a bigger intercooler help? Anyway, this is my first project car so anything you can help me with would be great.

Well, even though I'd just said in the post before yours that you could go with boost on a motor with a CR of like 9.5:1 and, with a good tune, be just fine, I would suggest that if you're thinking of going with boost from the get go, then don't go with a higher ratio - I'd suggest 9:1 (8.9:1 for some reason seems to be what it always actually ends up). There's a reason most boosted cars run lower compression ratios, and it's because it IS actually easier to deal with - I was just saying that you CAN still boost on a higher CR, you just have to be more careful of certain things. If you really wanted, you could boost an engine with a 10:1 CR, but I don't know that I'd really suggest building the motor that way planning for boost...although I do believe many drag cars (supercharged or turboed) run a CR that high or higher. Then again that's a totally different world, where they can and do tear down an engine completely between races.

Bottom line, if you're building an engine planning on boost (especially higher boost, which is usually why you build the engine, so it can handle it), I'd go with the 9:1 sorta range. However if you're thinking N/A to start with, but want to still leave yourself the possibility of boost down the line, 9.5:1 or even 10:1 will still probably be ok for a lower amount of boost (if I had to throw a number out there, I'd say 8 psi or less although that's totally arbitrary). Again, tuning is the key regardless.

the way I see it.....

stay N/A if iether you can't afford boost in the near future or your just one of those people that needs to 'prove a point'. not saying that it is a bad point to prove, just don't be one of those people that looses a race and cops out to 'but its all N/A'

otherwise, boost

yes, both combos need to be biult when taken to extremes. but there are differences in the biuld. like already stated, differeing compression ratios. also, with boost you can get away with opening up your ports bigger without worrying about sacraficing torq becouse the air is being stuffed in there and does not rely on port velocity as much at lower rpm. also, the two respond diffetently for cams. you can get away with a n/a cam on a boost motor, but not the other way around. and of course with boost you will do better with a boost cam than an n/a cam.

now that you make me think about it, if you really biult an N/A motor, then wanted to lower your comp for boost, you might be able to get away with doing some bowl work or even just a thicker head gasket.

either way, I say boost for now, and biuld as you can afford. cause you can aways just up the boost. can't do that with N/a



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when you beat someone in a civic people wine and make excuses
when you beat someone in a cavalier they pull over and check under thier hoods

I think its important to just sit down and think about what kind of end goals you want to have and go from there.

Do you want 30+MPG?

Do you want reliability, daily driver?

Are you aiming for a certin 1/4 mile time?

Do you want massive HP and TQ. numbers?

How much do you want to spend?

Is it worth putting all this time and effort into a j-body, or can you find a better car to start off with?
( I dont care what people say, having a 12 second cavalier is in NO way having a reliable daily driver, 8 cylinders is a different story)

just stuff to think about man

My motor N/A put down 171whp/158trq...... That was with stock injectors, and stock after cat exhaust, and a crappy HPT tune. My motor was also built for 'boost'. The compression is slightly lower then stock, the crank is stock (N/A motor should have it lightened and knife edged), the cams are smaller then HO cams (at least on the intake side.... think hybrid/secret stage 2 cams), and the head was only mildly ported w/ stock size valves. Plenty of room for improvement.

Karo's motor put down 250whp I believe OFF SPRAY...... That engine had the best of everything.




SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

built n/a, then later when you have the money, just boost it. you will have to tune it and run high octane, and tune it well. thats how i see it. i have a N/A built with 10.5 cr and maybe next year if found are available, i will boost it.

If you go boost on a higher CR, think water/ methanol injection instead of, or in conjunction with, an intercooler- it offers greater cooling effects than an intercooler (especially when you're not moving fast and that intercooler is doing more harm than good), and it's pretty cheap. I've even heard of using water/meth spray on an N/A build to increase knock resistance (of the engine itself, not the fuel).
I haven't done it myself because of lack of funds (I'm a poor college student) and because my car is basically stock right now (b/c I have no funds...), so I can't vouch for it's effectiveness, but it might be worth considering...



LD9 F23 FTW!!