Engine Internals

[Matt H.]

I don't know anything about engine internals, so I have a few questions.
1. As far as pistons go I just need to know a bit about compression, what's better high or low, and what is better flat top or dished.
2. I just want to know who all makes pistons, crankshafts, and connecting rods that will fit the stock 05 gt block.
3. What all should I replace if I want to get a supercharger or nitrous

 

[cleveland]

As far as boosting through supercharging, a compression ratio of about 8.5:1 is ideal. But most people who supercharge street vehicles do not pull the engine and replace internals. Supercharger manufacturers design their basic kits for stock engines without the need of internal upgrades, the Saleen kit, for example, boost the stock GT 4.6 by about 4.5lbs and produces about 50% more power to the tires.

As for who makes components for the new 3valve, I have no idea. There is no mass market yet, thats for sure.

I suggest you keep the boost levels reasonably low for your street vehicle so you dont risk damaging your stock components.

No offense but if you are asking these questions you have no business getting anything more than the basic kits that are already supplied by Vortech, Paxton, ATI's Procharger or Saleen.

If you are interested in nitrous injection not many self and car aware people would spray anymore than a 125 shot to this motor without building it for nitrous use. 125 may even be pushing it.

-Dan

 

[1ba96gt]

1. Compression effects HP. Higher compression makes more, but allows less boost/spray. You need a balance between compression and the size of your power adder of choice. Flat top and dish are means of changing compression. Dished lower compression various amounts based on the depth of the dish.
2. Everyone pretty much that made the old 2V stuff can build a short block for a 3V. With the shortblock the differences are minimal. Manley, Eagle, CP, and Diamond are just a few companies.
3. If you want to go big, which if you are spending the money you should or you'll end up doing it again anyways. Get a full rotating assembly. Crank, rods, and pistions to hold up to the abuse you want to laid down.

Warning: Building a shortblock is not cheap! Decide what you'll final goal with the car is before you do it and be realistic. If you want some more info you can PM me but I hope this helps.

 

[Matt H.]

No offense but if you are asking these questions you have no business getting anything more than the basic kits that are already supplied by Vortech, Paxton, ATI's Procharger or Saleen.

-Dan

So, do you think I can run a vortech or saleen safely with a stock engine?
The only reason I was even thinking about changing the internals was because I was worried about engine detonation if I add a supercharger or nitrous

 

[Thunder Road]

The weak spot is thought to be the pistons as the distance to the first ring is short.
Personally my opinion is if you want to have a supercharger, replace the pistons, rods and crank with forged pieces, no matter whose blower you use. The engine will last much, much longer. And if you are going to go to this much expense, consider a stroker crank and rod combo. You can get 300 cubic inches out of this compared to the stock 281.

 

[CatmanJJ]

I've wondered what the new 3v 4.6 since the limit that most people say is around 400 rwhp on stock 2v. So far I've seen some companies quoting as much as 425-450 (I think from what I've read) on the new 3v. Interesting to see how that goes since I thought the internals were basically the same as far as pistons and rods are concerned.

 

[cleveland]

So, do you think I can run a vortech or saleen safely with a stock engine?
The only reason I was even thinking about changing the internals was because I was worried about engine detonation if I add a supercharger or nitrous

Engine detonation wont be a problem IF you have a great tune, thats a big if.

I will be running a Saleen SC sometime in the next 25k miles and I wont be pulling the engine to replace anything out of it. A 4 PSI boost doesnt scare me, these 3v engines are not as weak as some are saying. Even the Saleen SC cars are driving around with full warranties and no problems, if an engine blew up Im sure we would have heard about it by now.

Now, Vortech apparently has blow up a couple in their quest to see when the engine lets go.

-Dan

 

[Matt H.]

well, do you think the price on the saleen will go down soon, because the reason I am looking at the vortech is because of it's price, if the saleen would go down, I would definately go with that

 

[Matt H.]

I was just doing a bit of research and I noticed that at sean hyland motorsports, they build a shortblock for the 05 stang and it says it is good for up to 500 hp, so I wanted to know how much hp can the stock block take, and once I reach a certain level of hp, do I have to buy an entire new block?

 

[cleveland]

I was just doing a bit of research and I noticed that at sean hyland motorsports, they build a shortblock for the 05 stang and it says it is good for up to 500 hp, so I wanted to know how much hp can the stock block take, and once I reach a certain level of hp, do I have to buy an entire new block?

From what we have already seen, the stock 3V can handle just about that much. If 430 RWHP can be made to the pavement Im sure the engine is already pushing close to 500.

If you decide that you want and can handle 500hp it would probably be best to have something over engineered for it by a healthy amount if you are throwing away your stock engine for a new one. A waste of money IMO for a 500hp limit, thats no better than stock.

-Dan

 

[mikeelia]

I don't know anything about engine internals, so I have a few questions.

Forgive me, but if you begin with this statement you should be either:

1. Learning a lot more before you consider building or modifying any engine; How can one ask a "few questions" about something so complex?; or

2. Hiring [paying] someone competent to do your work for you. [This option probably allows you to only ask a few questions].

I am not trying to be nasty, but adding a S/C to any engine is complicated [more so if done right]. Some people simply plug in nitrous oxide on any old engine, but then engine life is pretty short. Doing either of these things "lite" so as not to harm the stock engine means that it probably isn't worth doing for the money [$5k for 40hp? What a waste of money.]

Mike Elia
05 gt lime
87 Regal Turbo T

 

[cleveland]

[$5k for 40hp? What a waste of money.]

Where the heck did you pull that number from? Even if you are using that as an example number its a poor number to use since its soooooo far off pace.

Example: Stock GT makes ~270hp, Saleen SCed GT makes ~430rwhp @ 4 PSI of boost. Thats far from 40hp for $5k, thats 60% more powah (160hp) with only
4 PSI.

-Dan

 

[mikeelia]

Where the heck did you pull that number from? Even if you are using that as an example number its a poor number to use since its soooooo far off pace.

Example: Stock GT makes ~270hp, Saleen SCed GT makes ~430rwhp @ 4 PSI of boost. Thats far from 40hp for $5k, thats 60% more powah (160hp) with only
4 PSI.

-Dan

Dan,

I just pulled that number out of the air as an example for someone who doesn't know much about cars to do "minor" tweaking involving something as expensive as a blower. Do you think someone that doesn't know much about "engine internals" is going to get their engine to approach Saleen's numbers [advertising aside]? I personally doubt it, though maybe they could be lucky and do so. It usually takes an pretty experienced and knowledgeable engine builder to get those kinds of gains.

I know a little about boost [albeit with turbos], but not on pistons with hard-anodized top crowns and ring lands and starting at 9.8:1 C/R. I know some drag racers use this process, but I personally am not familiar with it with the eutectic pistons the stock engine uses. I personally think the bottom end of the stock engine will handle a lot more, but just how much remains to be seen.

Mike E

 

[cleveland]

Do you think someone that doesn't know much about "engine internals" is going to get their engine to approach Saleen's numbers [advertising aside]?

Tuning always has to be done on a dyno for such a bolt on as a supercharger. But then again Saleen flashes your PCM for you so it pretty easy to get going if you follow directions and have basic mechanic's skills.

http://www.modularfords.com/forums/showthread.php?t=29196

-Dan

 

[Matt H.]

Forgive me, but if you begin with this statement you should be either:

1. Learning a lot more before you consider building or modifying any engine; How can one ask a "few questions" about something so complex?; or

Well, maybe you should think about the fact that I have to learn somehow and I figured maybe some people here would know, and there's no way I can afford to pay some guy $10 an hour just to tell me about engines when I could just ask someone here for free

 

[mikeelia]

Well, maybe you should think about the fact that I have to learn somehow and I figured maybe some people here would know, and there's no way I can afford to pay some guy $10 an hour just to tell me about engines when I could just ask someone here for free

Matt,
That's not the problem, I know I've learned a lot from lurking on sites like this, but I also do a lot of research on my own, so I was surprised at the way you asked. No flame intended. That's just a pretty advanced need to try to obtain a answers to fill. I guess I was just trying to say that S/C is pretty advanced work if you aren't all that into the vehicle already. Again, no flame intended.

Also note that "free info" [including or especially mine!] in many cases is often worth exactly what you pay for it.

Good luck.
Mike Elia

 

[gp001]

I think everyone in here missed asking the pertinent question: WHY do you want to supercharge? Are you looking to go drag racing? road racing? or just want to say "Yo, check out how dope I is wit dis tight supa charga"

Before you attempt mods you should really do more reasearch than asking about compression and pistons. Learn how SC's work (he specifics, not just it rams air in the motor). Learn the pros and cons of increasing boost in the engine. Consider the other components of the car that will need addressing to handle this increase in HP.

 

[2MFF-Z28]

Say it bro!!!!!!!!!

 

[gp001]

Say it bro!!!!!!!!!

it

 

[SMP]

The question is how much can the stock tranny take