348 Performance upgrades to get to 360hp

Andy, is that NOS system in your 348? What is it and how does it work?

 

Well we really don't need that much $ and it depends on how much dyno time it takes. If people on the list have access to parts we can scavenge we can do it cheap. I got the car and the knowledge and a NOS design in mind. If some has old but useable boots between the T body and MAF that could be a freebie, if someone has access to 8 ECT probes and guages that could be a freebie, I have a Nitrous and nitrous bottles but need solonoids AN lines and a box of jets and two fogger nozzles and we would have 90% of a system right there. Don't forget we don't need to make a prety system yet we are looking for 1) will the 348 manifold flow a wet mixture, 2) how much NO and fuel = how much HP gain

 

Well direct is the way but it is always harder than you think and more costly than they say. You may have a raised injecotr bed and may decrease the efficiency of the stock injecotrs since you spray futher away. you may not even be able to close your bonnet if you raise the whole mess if there is plating of your manifold which would be the hot set-up but very costly.

 

Yes agreed. I'm a tracker too but love the topic. In fact I am a complete tracker as in illegal fully guted tin can on slicks and very loud straight pipes. I sound way more *****in than any 360 but I'm slow....NO horsepower. You and I need to figure out how to pull some molds and make CF body panels. The body panels are easy to make but I don't know how to make such a large mold. When I do small projects the CF vs E-glass is not that much more. Eglass about $7/yrd cf about$20/yrd. There is huge weight to be stripped from the 348. Think about where the battery is in the 348 post 1992. if you had a choice what would you rather carry at the end of a 14ft pole 40lbs or 13lbs? My race battery is 13lbs like a motorcycle battery!

 

What about getting someone like Noswizards or another Nos company to back us. You would think they would be willing to pay for the research (not like they havent before) if they thought they could turn a profit. Im sure they could sell quite a few of these kits to 348 owners with the test results, especially if the tests were done by some very well respected and knowledgable people on this site.

 

Why not NOS then since they seem to have the most logical set up for this engine. All we really need to do is find someone willing to take thier car to them and put the system on thier engine for testing. If it fits great if not we try something else. I'll email thier tech line and see if they are interested but I do not have the time to take my car to them so we will need a volunteer to take up that task. Anyone interested? If this kit works I will be first in line to buy one. The installation looks fairly easy and Nitrous really is a kick. I used a 250HP version of it on an old GM big block and it was great. I think a modest 100HP version would make the 348 a real monster. Anyone agree?

 

Well NOS used to be right around the corner from me. I learned my craft of NO on their stuff way before there were electronics to prevent engine blow-ups. Anyway, yeah who wants to be the guinie pig? Not Me. Frankly I don't trust them to stop adding jets until something breaks. If I was doing it on my engine on the dyno I would run up an extra 150hp and that is where the test ends. Sure anyone we could get to do the job gratis "could" say they would stop after 150hp but would that? What would they break during installation? I know some of you guys have taken your cars to FNA mechanics only to have something else broken upon return that was not broken before. So takes responsibility for that? Also, there is no money in it for these guys. Not enough of these kits would be sold. There are about 15000 of any chevy made a year and that is GM limited production on say corvettes (127000vettes from 1997?) There are total 5000? 348's???? Which two of you guys on the list would actually buy this system?

 

And now back to regular programing. LOL. If you are gonna tear the engine down, yes get the light con rods. Running 11.0:1 compression ration I think would be do-able. As I have pointed out before in previous post, the Euro 348 GTB/GTS models had 10.8:1 compression ratios. I would imagine you could get away with another .2, taking it up to a full 11. The biggest question would be fuel. Here in California the highest octane rating we have is 91 at the pump. In England their premium is 98 octane! There are stations here that sell 100 octane gas, but it is EXPENSIVE!! So if the fuel doesn't have a high enough flash point you could end up with detonation problems. But then again the 355 is running 11.0:1 compression, and did it using the Motronic 2.7, for the '95 model. So I really don't see why you couldn't do it with the 348 engine, other than low octane gas. I would also agree that getting the head ported and polished will help with getting more air into the motor. However if you are cramming in all that air, at a certain rate, and still are restricted and the back end, the port job won't be as effective. So you will need to have some custom headers made, to optimise exhaust flow. I would get them ceramic coated inside and out, to keep the heat inside the header. This gives you more power by keep the engine bay cooler, and all the heat inside the header to get the exhaust out faster. If you are gonna keep your cats, I would get a set of Hyper Flows. They say that they are only 4% difference than straight pipes. Since you are getting your Throttle bodies ported and the intake top openings matched, why not get the intake runners smoothed out. When I had mine off, the were VERY rough on the inside. This has got to be bad for air flow. I looked into getting mine extrude honed, but decided to save it for the next major, since I put that money towards getting a new bumper, and some painting. Anyway, Extrude Hone, the company that started it, was pretty pricey, but they do aerospace quality work, so you get what you pay for. Since you have talked to Norwood already, ask them about getting the crank knife edged. This could also get rid of some rotational mass, and possibly release some more power. Titainium valves would be another option, to lighten things up. Back to the air box. As you know the tubes that connect the box to the intakes SUCKS! You could probably make a smooth tube from fiberglass to help with that. But of all these suggestions it really depends on how much you want to spend, for the amount of power you can get.

Just my two cents.

 

That is the system on the car, no problem with the fuel rails.

I run 100bhp extra, which is plenty to make me keep up with the big boys.

Andy.

 

Fantastic! Is it the same system I posted a link for? How has it been working? Any problems installing it? How has the engine handled the additional HP and what kind of performance increases have you experienced? Please tell me all you can about this. I am very interested in doing the same thing to my car.

 

the system i used is probably last years model 08008nos i think it looks better than that one, Ill take some pics of engine,it looks very cool the way its wired up, when i took it in i told them i wanted a Ferrari installation not a ford,very pleased with the results,there are a couple of Cs drivers that could testifiy how fast it is.

Andy
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Andy,

that engine bay is BEAUTIFUL! How did you get that aluminium colour to look so uniform? Is it sprayed? coated? plated?

What other detail work lurks in the bay? Mine has been totally neglected by previous owners and I have to start some sprucing up!

Drew

 

The only chance youve got is when the engines out, my garage let me work on it when they did the service, The air box was striped of the crinkly and sprayed wheel colour.Good luck.

Andy.

 

Andy's system definately solves the problem of the direct port vs wet flow. However, one of the most important aspects of all NOS systems for street is the non-interference with stock systems. So If you use a system that uses a NOS/fuel fogger ring that plugs into the FI port on the manifold then plug the FI into the ring, you have the FI now about 15mm higher and away from spraying into the port under normal operation. So does that effect the performance? I bet it does. You may not know it when the NO/fuel is flowing but 2 10lb NO tanks only give you about 3 minutes of WOT.

 

JJ,

assuming a track car I say remold the bumpers (rear first) then roof, cut out the tub and do it in CF panels ala the C6 vette. Weld in a proper roll cage and then gut the oem door reiforcements. As to cams you can do all that great stuff but if you do not have a plan for optimizing the ECU mapping you are just kidding yourself. The reason the challenge straight pipe works only as well as a tubi with cats is because the ECU's are not optimized. With ALL your potential mods the ECU is your BOTTLENECK! You must either use an editor to reprogram and flash your Eprom or gut it all out to a new aftermarket ECU. IMO you could gut all the 348 electronics for a 50lb weight savings and rewire for just what you need, an ECU and brake lights, and head lights.

 

I'd like to hear what andy has to say about this. Andy, have you noticed any performance loss when not using the gas? BTW I appreciate the response. I have been curious about this for quite some time and you are the first person I know to have done it. Have there been any adverse effects that you are aware of?

 

Thank you for the comments Andy! I'll bet there are more than a few 348 owners that would be interested in hearing all you can tell us about this. Things like the cars 0-60 time or 1/4 mile time, RWHP increase, ect. Also, information like how long have you been using it, how many miles you have put on the car since installing it, how often you use it, ect. I know I'm being a pest but I really want to know as much as possible about this. You are the point man of an experiment that can be beneficial for all of us.

 

Barring some type of forced induction system, (my preference of course), I'd think this is the way to go if you actually want to make real horsepower gains.
Also, I'd bet this would be MUCH less expensive than a twin turbo setup.
As for duration, (less than 3 min.s @ WOT), I'd not be too concerned about this on the street. I can't remember a ride in my Turbo car that I actuall had the throttle FULL OPEN, for more than a few seconds at a time.

 

Well Jeff,

This is actually significant because of the way NO is really used. You see the bottle is not that presurized. It has perhaps only 700psi in a 1 cu ft can. As the gas solinoids open the flowing liquid turns to gas and frezes in the orifices thus altering flow as the quantity and pressure of the gas changes. Also, most users use the gas until it is gone and do not refill it daily just like their gas tanks in the car. So as the pressur changes the porfomance of the unit changes. I was a bit more nuts and have a huge D cylinder of NO kept in my garage and after any use I alwys topped off my tanks. Also the pressure and output of the cans change due to ambient temps like sitting in a hot car. As the gas chages from liquid to gas the can gets cold and decreases the flow. They make heater blankets for this for drag racing but ricky racers never hassles with these things. So 3 minutes is being liberal and the 3 minutes you get are not all uniform. NO is for killing a Porsche next to you at a stop light. Turbos are for going fast all the time any time. Don't get me wrong I love NO and was the person who voluteered to do the research even though I'm a road racer and No has no place there.

 

Very good!
Thanks for the basic lesson in NOS. I've never used it and I read each of your explainatory words with great interest! NOS has always been an interest of mine and I NEEDED someone to explain to me some of the shortcomings. Thanks Billy.
Makes me love my TURBO car even more......
Sounds like the big drawback of folks adding turbos to their car is the price of a balanced turbo system. It is very pricey. I most likely would have been shy about it too. It is nice that it was already all onthe car when I purchased it. Still, I think it, or a good Supercharger system, are the ways to go for real HP gains.

 

Jeff,

I agree with you 100%. Life is a bag of trade offs. No is great because it make huge HP cheap and easy. Turbo is great because it is really always there and really changes the overall charactoristics of the car. Even Turbos can have compromises like the spin up properties of a street turbo vs where a race car turbo operates at. Sometimes and lots in the 80's (before the now better turbos) we used to use NO with the turbos just for a blast to get rid of turbo lag. Now turbos spin better and there are better designs relative to how street turbos are used such that there is almost no lag.

YMMV

 

This new system runs at 900psi and is kept there with the use of a bottle warmer with a temp gauge on there, this way the last hit before u run out is just as good as the first, i did not have this when first installed,it makes a huge differance.

Airbarton I have no dyno readouts for performance, on track days on the NOS this car goes past ALL the faster cars, and when they come and talk to me after they are very pissed,CS,F40,288GTO,360s no problems.you have to chose your moments as you only have so much to play with, i usualy let them go past for the first few sessions then, seeya.

Andy.
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Andy,

Can you get us some closer pics of the Nitrous inlet side the fuel rail area. Did your ssytem use the stock fuel pressure regulators? How have you set-up your triggers? Dual triggers one to arm one set at say 3/4 throttle?

Thanks!