I have decided to scrap the idea of dohc mivec and turbo the existing motor, but I want some fead back and some answers. I would like 8000 revs I want a redline of 8000rpms, second I want it to do it safely so I want to beef up the internals like pistons, rods, a better can for those high revs, and beefy valve springs. I thin rpw can hook me up with the engine components and I think that I am going to go with Road Race on the turbo. What do you think? any comments are apreciated.

 

8k RPM's is kind of high for a motor with such a long stroke. And I know you don't want to change the crank and lose displasement.

 

Probably wouldn't need to change the crank but a lot of work would have to be done to make sure it spun correctly at those VTEC style RPM's, but you're very right as far as the rod length issue is concerned. This motor is not meant to spin insanely fast as it's supposed to give your decent streetable torque in the low and mid range. The current max rev limit (either stock or from Road Race) is perfectly acceptable for the level of tuning most people will encounter short of doing a complete rebuild or race stlye motor with lightweight internals. Upgrading valve springs should you opt for a turbo cam or some wild grind, is however a good idea.

 

I figure hell if V8's have been doing 7 to 8000 rpm revs in the 60s and 70s there should be no reason why our 4s shouldn't do the same thing. I know the stroke is longer than say a b16a, but at least a 7000 rpm redline should be attainable. I think that I am going to need that extra gran or two grand If I am turbo'ing' the egine, because turbo lag eats you up untill about 2500 or 3000 then, bang! kick in the ***. If only you had that extra 1000 or 2000 revs the gains would be great, but you have to have the cam to do it and our cams cant do it...they could but the hp and torque curves would drop after 6300 or so, so the cam would have to go and rods and pistons are a must for me anyways, sense I am going turbo, plus I want to step on the gas with some reassurance that I won't throw somthing. Valve springs I think have to come with the cam because I am turning thos extra rpms and I will almost deffinately bend or break a valve. Honestly I have planned this day out a long time ago. I have finally got money to do some really nice stuff and I want to make sure I am doing it right, and doing it the best that I can. Let me know what you think...What would you do with some money

 

7k is obtainable providing you do change rods/bearings/pistons/and in actuallity you probably don't need new vlv springs or retainers... just get .050 washer and install them on the springs as well as the retainer and locks. This will give that extra force on the springs which will take it and you should be able to get 7k daily. Then with that in mind you'll have to kick down a little sweet talking and probably some extra cash to RRM for the ecu upgrade with your specified rev limit. I recommend sticking with stock cam for going turbo as no one has seen effects of other cams on turbos yet... don't be a guinnea pig on this one especially if your going for the revs your going for. I say this as RRM ecu is tuned on stock cam and stock limits. Get your motor built then do turbo then ecu to your specifics. Thats my recommendation.

 

Thanks for the advice

 

so boe are u saying u r not gonna be a gunnie pig for a turbo ground rpw cam... or are u holding out for an RRM secret that we dont know about yet. possibly part of stage 2?

 

Not going with cam as our tests have shown greatest of results with stock cam... that cam just somehow is almost perfect for turbo. Thus why invest in another style that i honestly don't think will get me that big of gain. I'd rather just develope the lancer a bit more and crank up the boost to get the power. Although i was a little zealous at first on stage 2 mods the results i've seen thus far on 9psi is just great. I'm just smoking people. My only drawback has been a tire issue which we finally got corrected.... i now have the right size tires for the car(slicks) so hopefully within a month or so i can get to the track and make a new record. We'll see.

 

There are only a few ways of making more hp. Raising the displacement will yield more hp, and also raising your revlimit should theoretically raise your redline as well. This is depicted in the equation, "HP = Torque x (RPM at which you make the max torque / 5252)"

Here, you can see that by increasing the displacement or by increasing the efficantcy of your motor, you will gain more torque, therefore increasing the hp. By increasing the RPM at which you make the maximum torque, you can in fact, get more hp as a result.

There are other ways to get more hp as well, such as diffrent fuels. That is only because diffrent fuels, such as ethonol, have more energy per volume, increasing your torque. a turbo charger or a super charger will in fact emulate a bigger engine then you already have. The atomosphere in which we live in is 14.7 PSI. Therefore, any engine on earth at sea level will get "14.7PSI". Using the formula, "Emulated displacement = (1 + (amount of boost on engine / 14.7)) x nonboosted displacement", you can infact figure out what your displacement is. For example, if you had 14.7PSI of boost on your car, your displacement will be effectively doubled, giving you a "4.0L" engine. Therefore more power.

For the US lancer, gaining displacement using mechanical methods (bore-up, stroke-up) seems inpracticle and expensive. Turbo's seem to be the way to go.

Now addressing the question about rev limits. By just increasing your rev limit, you will not gain any hp. If you look at your dyno graph, you will see that your torque curve will start to drop way before the rev limit. If you were to keep spinning it faster, the torque will only go down, resulting in no gains in hp, and more wear and tear on your engine. To move the torque curve up to take advantage of the 7000-8000RPM redline will require a few essencial things. First of all, you will need a new camshaft that has more duration and lift. You will also need new
high compression pistons to effectively take advantage of your new duration and lift. Beefer rods may also help, because raising your redline will oftentimes put more stress on your motor then a turbocharged motor. One thing to watch out for is "rod to stroke ratio". This is very important in a high reving car. Like someone said, you may have to destroke your engine. This will lower your displacement. You may be able to bore and sleeve your engine for bigger pistons to negate the effects of destroking, but it will be very costly. You must also make sure that your valvetrain is up for the job. This includes your valvesprings, and possibly your retainers. Also, the dynamic balance of your engine is also very important. A stock engine will have specific tolerances for the dynamic balance to prevent unwanted vibration from the engine at it's max RPM. Increasing the RPM may exceed the acceptable dynamic balance, and may cause unwanted vibration. This may eventually lead to a decreased engine life, not only because of the wear and tear, but because of the vibrations. This can be cured by balancing your engine. You will need balance your counterweights on the crankshaft with your rods and pistons.

Finally, make sure your car is dynotuned with a wideband O2 sensor and a SAFC. This way, you will optimize your power and take advantage of all the parts on your engine.

In no way is NA tuning cheap. If top speed and dragracing is your thing, definetly stick with forced induction. Forced induction is definetly a cheaper path.

If I missed anything, please add some more information. Thanks.

 

dude wtf your post is unneccessary! Like I stated above, torque does go down with higher rpms(on our stock cam) I was thinking about trying a different cam for high rpms which wouldn't drop torque at high revs on a dyno chart, but I have talked to rob at rrm and he has told me that the ecu for turbos brings torque up and smooths the curve out so that the engine pulls all the way past redline, so I don't think I will go with a new cam, maybe new valve springs, rods and pistons in the future, but as for now I am going to go rrm turbo all the way. So dude next time you post just read so you don't waste your time typing all that crap. Like any one in this forum is going to run alcohol in their car, everyone knows about bore and stroke, we know about torque curvs, .....?

.................................................. .................................................. .................................................. .....................................wtf

 

The information that was posted earlier was not intended to offend anyone, and it is very objective in nature. I joined this forum because I liked the enviroment in which people were very helpful to eachother. Everyone seems to have something in common, and that is determination to improve their cars. Yet, I kept seeing people who were being misguided and people who were victims of marketing. The information above is not only for Proksy, but for everyone to read if they cared. The previous post was not created to imply that Proksy, or any others who were offended, do not know anything about engines. I disagree that this post was unnecessary. I believe many people will benifit from this thread. There are many people who wonder why turbo's make more power, or why their intakes gives them more power. Even the general question of, "What is power?". For all the people who took offense to my post about engines, I apologize. I felt that this forum was very knowlageable, and mature. If this is not the case, I will refrain from posting on this forum. I do not intend to start a flame war, nor is this post an attack to those who were offended.

You wanted advice on a boosted motor w/ a higher redline, so I gave my input on how difficult that feat will be. Really, take it or leave it.

I just want to share my thoughts and ideas with the people here. Thanks.

 

I agree with project, he was simply sharing his knowledge, which didnt seem off topic to me at all.

 

ya nice info, but this isn't the newbie forums. I don't intend on reading a 1000000000 word essay on torque and horse power and how tuning is a challanging thing, but seriously I think some people would actually like to read this I just don't think that his wonderful post fit the question that was imposed which was: What do you think about my idea of putting a different cam in while running a turbo? So the nature of my previous post is not to demean Project_v, but in a way let him know that his post is very lengthy and that, while I do appreciate his well researched(cough plagiarized) post I just felt that it didn't pertain to my question that is all

 

Be sure to have the video camera going so when your 4G94 hits 8k we can see what happens when it throws a rod through the crankcase.

 

If you winning car shows with the engine you have why waste your money on a new engine one what is the point just keep winning.