CulRidr's MP3 N/A build (~150whp goal)

Gah...more money being spent, maybe. Was talking to my local go-to guy when it comes to welding, and for the money being spent and the "return on investment", I'll probably just go with a better collector...probably a 200$ job (which would essentially double the cost of the header, but that's fine if it adds a few more ponies compared to what it can normally do, especially with what I'm throwing at the car).
just make sure its a merge collector (will have a neat "star" shape when you look inside), merging using 15 degree bends.
The next thing he talked about was headwork. His "stage1", as he has worked on Proteg heads before, would apparently get me ~10hp in the midrange, and at least 5 in the upper range. 650CAD is what he quoted me for ~20 hours of work which includes a PROPER port&polish (might need to talk to him about doing a wee bit of work on the intake manifold...more convos to come with him for that) and some combustion chamber work.
head work will free things up a bit, and $650 doesn't sound like a great deal of money for a decent amount of head work - just make sure to get before and after flow bench data, to prove that it actually has made an improvement ;)
Further question. I won't be going with the custom rod/piston combo, but if ever I wanted to up the RPM range a little (say to the 7500rpm range), better (read: stronger) rods would be recommended yes? If so, then any forged rod would be better then the stock crap...The question is, are most forged rods lighter, ~equal or heavier then the stock crap. Anyone know?
personally, i wouldn't rev anything with the stock rod length to 7500 - but if you had to, the pauter rod would be strong enough to deal with the forces. forgies are normally heavier as more material is used and they are made to be a lot chunkier than the stock rods.
 
just make sure its a merge collector (will have a neat "star" shape when you look inside), merging using 15 degree bends.
Ya I'll make sure. The Ractive is apparently not stainless steel, so before I even consider it, I'm looking for pictures of the inside of the collector to see if it's decent or not. If it is, then I'll probably pull the trigger. Otherwise, I might go with the Pacesetter as it costs about 330CAD (plus shipping) and it's apparently already jet-hot coated...

head work will free things up a bit, and $650 doesn't sound like a great deal of money for a decent amount of head work - just make sure to get before and after flow bench data, to prove that it actually has made an improvement ;)
I'll make sure, don't worry. That's still a chunk of change so I'd want to see results :)

personally, i wouldn't rev anything with the stock rod length to 7500 - but if you had to, the pauter rod would be strong enough to deal with the forces. forgies are normally heavier as more material is used and they are made to be a lot chunkier than the stock rods.
What about Crower rods? I've got a possible deal for a set for 300CAD...would those be able to take it? Been searching around but there isn't THAT much info on them.
From all the reading I've been doing (including this great thread, more specifically post #14 by installshield), 7200rpm might just be where I want my red-line limit on stock rods...would it really be worth it to put in forged rods for a few more hundred RPMs, or is 7200 already pushing it?
I'd be curious to know the weight of a stock rod...
 
the engine, according to installshield - will start flying appart at 7400rpm on the stock internals. mass, and acceleration are the enemy here - a forged rod may be more resistant to stretching due to additional strength, but it will weigh more, which presents problems. The only real way to get around it is to reduce the piston acceleration which means less revs OR longer rods.

7200rpm is really probably ok...a bunch of us routinely spin the stock rotating assembly to 7k without issue...bare in mind that it is unlikely that with the JDM cams that you'll be making power at 7k, so the benefit of spinning it faster is questionable.

however if in the future you get some twiggies or integrals, and want to run it up to 7500, the stock setup is going to give you grief.

Crower make good stuff - they'll be as good as any other rod in the price range - are you going with an FSDE stock replacement rod or an SR20 rod with a raised/oversized wrist pin? Like i said, you wont be able to take advantage of it with the JDM cams BUT its futureproofing your build...because you're taking it to a place where any significant upgrade will require you to open it up again.

Talk to jimmysuite - his build was nearly identical to your plan - and not 5 minutes after he reported that he had the car tuned, he was talking about a "mark II" build.

i'd either cap your rpm at 7000rpm and work the motor around that, or long rod it... anything more than 7000rpm and you're entering dangerous territory. You're flow limited to around 6000rpm anyway....so theres no short term benefit to adding monster RPM capability.
 
I don't plan on spending the money to go nuts on the RPMs, ie: higher then what a stock rod length could handle, which is why I'd stick with stock length, and although it is a bit heavier then stock (the guy I may buy them from will weigh them in a couple of days...anyone know what that weight is?), 300CAD for a set of essentially unbreakable rods when rebuilding an engine the way I am seems like a decent idea no?

Then again, if I don't plan on going higher then 7000-7200rpms, I guess there's no real point right? Or would it simply be safer? I'm trying to figure out what makes sense here...
Also, how high do the twiggys/integrals flow?
 
I don't plan on spending the money to go nuts on the RPMs, ie: higher then what a stock rod length could handle, which is why I'd stick with stock length, and although it is a bit heavier then stock (the guy I may buy them from will weigh them in a couple of days...anyone know what that weight is?), 300CAD for a set of essentially unbreakable rods when rebuilding an engine the way I am seems like a decent idea no?

Then again, if I don't plan on going higher then 7000-7200rpms, I guess there's no real point right? Or would it simply be safer? I'm trying to figure out what makes sense here...
Also, how high do the twiggys/integrals flow?

Added strength is useful yes - although perhaps not absolutely neccessary unless your existing rods are weakend/shagged. The extra weight does mean higher parasitic loss (more energy needed to turn the motor). The choice is really yours...if you never plan going more than 7000rpms, do new bearings and new rod bolts etc (good high quality ARP bolts, something like ACL race bearings or something) and you will probably be fine, especially with the engine BALANCED for 7000rpm - reduction in vibration etc can only be a good thing for longevity.

dont know about the integrals, but according to the guy who manufactured the twiggys, with adjustable cam gears to keep the power band useful, they will out run the practical mechanical limits of the FSDE (i.e. good for well over 8000rpm...) Thats not to say they are no good for 7000rpm...just pointing out you'll never build an FSDE where twiggys (and probably integrals) will become the limiting factor.

As i've said before, 150 is doable on bolt ons...twilightprotege did it years ago - so with a built motor you're going to have little trouble getting there.

Cams are really the only thing i think you need to reconsider at this stage ;)
 
I took my engine to 8,000 on the dyno jsut to see and it fell flat on it's face after 7400. Like literally flat, ran out of steam.
 
I took my engine to 8,000 on the dyno jsut to see and it fell flat on it's face after 7400. Like literally flat, ran out of steam.

you reached a flow limit then...the motor simply couldn't breathe up there.

a heavilly worked engine could breathe past 8k easilly... in fact, installshield had his on an engine dyno at something insane (8750 to 9000rpm), with ultra light aluminium rods and custom pistons - and some motoGP inspired head work - and afaik it was still making power. Pulled back for road use it makes 197hp all motor @ 8k rpm..

overlap on the cams, and head flow is key at high RPM to minimise pumping loss and get optimal flow..when you get into this kind of territory, an NA build could easilly cost 1.5 to 2x as much as a turbo build making 3x the power at 2x the reliability...

put simply, you ran out of puff because your head isn't up to it - nore does it need to be up to it...

could have also been a fuel problem - if the mean piston speed exceeds the burn speed of the fuel before the pistons passes 30degrees ATDC, the piston will literally outrun the flame front, causing huge power loss...with such a long stroke, piston speeds on unleaded gas is a bit of an issue :\

just for everyone out there (i'm sure you are aware of this) 8k rpm isn't advisable on the stock rod length no matter what the rods are made of (titanium perhaps being the only exception), for ANY length of time - the piston acceleration will fly the motor apart...hence why a rod rated for 500hp @ 6000rpm can/will/does fail at 200hp and 8000rpm...
 
Damn this thread is getting full of great info...
Now here's a question; if the twiggys are capable of going nuts in the high RPMs (beyond normal redline), were you saying earlier that with adjustable cam gears (which I'm getting) I could essentially have them useable at lower RPMs as well (say, 3500+?). If there's one thing I should read, it's the 2 MONSTER threads regarding these, but I haven't done that yet...
Ugh, I hate you for tempting me to buy the twiggys on sale on the boards (although another member hinted that he wasn't confident that the guy had a legit set...)

I took my engine to 8,000 on the dyno jsut to see and it fell flat on it's face after 7400. Like literally flat, ran out of steam.
What cams are you running right now (did you end up buying Greensleeper's cams?)? Trying to figure out why you'd push your turbo setup that hard, unless you mean you pushed it that high when you were still N/A...
 
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I did that 8,000 RPM run on boost, only 7psi but still she couldn't breathe... Put down 196WHP at 6900 though at 7psi that day.

That was on the Corksport cams, I'll be getting some integrals before the summer.
 
As for why I did that, jsut to see where exactly the power dropped off. The engine (at least with the Arias/Pauter combo I was running) didn't like to be run that high.
 
So essentially you're saying that the cams CAN breathe upto past 7000rpm then...interesting, even though I keep getting tempted by the twiggies...think I'd be able to get the guy in the FS thread to drop his price further?
 
What cams are you running right now (did you end up buying Greensleeper's cams?)? Trying to figure out why you'd push your turbo setup that hard, unless you mean you pushed it that high when you were still N/A...

There are legit reasons to do it on a boosted motor (see the old turbo indy cars..or turbo F1 cars, or any turbo drag car) - the thing is most people get MORE power than they bargained for by stock redline so theres no reason to do it turbo

NA you'll be wringing its neck just to see 200hp at the treads...so you take every last advantage you can get - pushing the head, combustion chambers, cams, manifolds, pistons, rods, the material composition of the engine, and your credit card limit to the absolute edge of sanity...

your goal isn't expensive to achieve, but the next 20hp will cost you the same as you spent again...the 10hp after that will cost you that much again, the next 5hp will cost you that much again...etc etc.

as for cams breathability - turbo motors operate on a slight variation of the same rules - because air is being FORCED in under pressure, the cams don't need to be nearly as wild to achieve massive results. again looking at the twiggy's - the guy that made them said that for NA they are a high performance street cam, for Turbo they are an out and out race cam - exactly the same profile.

having run my ride on JDM cams I can tell you, the motor will not breathe past 6k in a fit..especially once you start running your other mods..cam gears may help but i really think you ought to be looking at getting a regrind at the very least...
 
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"not expensive" is a relative term of course...
Now for me to do my research, is ALL the info I need in that twiggy installation thread?
 
"not expensive" is a relative term of course...
Now for me to do my research, is ALL the info I need in that twiggy installation thread?

between that and the original GB thread you should be set

another (cheaper) option if you want something a little milder is find a cam shop that can regrind the lobes on your existing cams...means bigger shims due to base circle reduction, but they can alter the profile on an existing set of cams and come up with a happy medium, made specifically for your application.

would certainly be cheaper/easier than trying to find a billet piece from a limited run.
 
I'm not so sure that the price of regrinding mine would be cheaper, but maybe something to look into. Lots of research to do still...
 
So I may have missed it but what are doing on the intake side of things?
 
I'm not so sure that the price of regrinding mine would be cheaper, but maybe something to look into. Lots of research to do still...

thats right man...lots of research

research is good - it costs you NOTHING.
study until it is clear in YOUR mind what you are going to achieve. This is your build...pick everyones brains but make the decisions yourself.
once you are comfortable with what you know and what you want to spend, pull the trigger, and not a minute sooner...many of us have made mistakes on our builds by following the crowd, or rushing into something and end up regretting certain things about stuff...
 
So I may have missed it but what are doing on the intake side of things?
K&N CAI (done), stock MP3 intake (no VTCS)...may decide to have it P&P'd, and the head is getting professionally P&P'd.

thats right man...lots of research

research is good - it costs you NOTHING.
study until it is clear in YOUR mind what you are going to achieve. This is your build...pick everyones brains but make the decisions yourself.
once you are comfortable with what you know and what you want to spend, pull the trigger, and not a minute sooner...many of us have made mistakes on our builds by following the crowd, or rushing into something and end up regretting certain things about stuff...
Amen :)
 
Talk to jimmysuite - his build was nearly identical to your plan - and not 5 minutes after he reported that he had the car tuned, he was talking about a "mark II" build.

i'd either cap your rpm at 7000rpm and work the motor around that, or long rod it... anything more than 7000rpm and you're entering dangerous territory. You're flow limited to around 6000rpm anyway....so theres no short term benefit to adding monster RPM capability.

Actually it was more like 6 minutes.... ;)

Altough I have been researching components for "mark II", I am planning on pushing the setup i have before opening the motor up again. My first (and only) dyno produced 148.5 whp with a rough road tune on the MT. Close to 150 is nothing to sneeze at but it wasnt quite where I would like to be. Even though I only pushed it to 6500rpm on the dyno, the hp curve was starting to look a little flat towards the end (5800-6500) My AFR's were way low during that range as well. I'm pretty sure I can gain more than a few ponies with a better tune and LW thinks the exhaust is whats holding me back. (i agree) LW you should see a PM soon about modifying my thunder header and exhaust for my current and future setup.

Cul - I'll try to get you a list of all my mods to give you an idea of the differences and similarities of our builds
 
In regard to why you should not be bumping your RPM higher

1. undersquare engine
2. you don't have a high flowing cylinder head design like a Honda
 
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