126mph at 490whp letting off, I'd handle your race gas or meth forget what you had at 15psi pump

 

Sad to say my race gas map will tax that ***. You wont get to chance to run it tho, cause that tune is old news.

 

A built engine doesn't guarantee you won't run into some stupid problem down the road like an injector going bad and burning up a cylinder, or something with the engine management going wrong, or the A/F sensors get messed up and you start running lean and do damage

It doesn't matter if you're built or not, stupid crap can and does happen.
I agree with the "if it ain't broke, don't fix it" philosophy unless you just know you're going for more power than the stock block can deal with


I think even my lowly power is completely stupid on the street. It's fun, and I use it every chance I get when it's reasonably safe, but there's still only so many opportunities you can find since there's often traffic to deal with

 

While we're on the subject of built engines, what is the feeling on gains from head work on highly boosted FI applications. I'm not talking about cams, because everyone knows there is a reasonably substantial gains from those. But in terms of things like porting and polishing, it seems like with boost, the gains from those kind of mods are going to be minimal.

 

any time you open up the heads or intake/exhaust, you're going to open up your top end rpms power some, at the expense of low rpms power

 

we have a good head design,but port polish should not be discounted.not only does port expand the range of the motor but polish helps with detenation.which will build power by allowing more boost/timing

 

Good info, thanks go-fast. Its crazy how expensive headwork is though.

 

to do it right it's a labor intensive proccess,add the skilled labor aspect and it starts to make more sense.

 

How reliable are built engines compared to those "built" from the factory, such as the upcoming GTR? I thought if you build your engine, like shortblock, it would last and be just as good as those engines made for FI..

 

Why exactly would a port/polish job adversely effect low-end performance?

 

loss in air velocity at low rpms

 

I think port work is a waste for most sub 700whp builds. I have put down the same or better numbers as comparable set-ups on PUMP gas as other cars that have come out of Forged. No doubt it can help, but not needed for most. I have some pretty high goals and I didnt do it.

 

Speaking of your goals, I'd like to know when we can expect an update on what you're gonna do now that you're selling a bunch of you're stuff.

 

I may be selling my POS, been a pain in the d!ck for too long, but that is neither her nor there.

 

No problem Alberto, no offense taken, but all our 4.2L stroker build with APS extreme turbo systems, make a MINIMUM of 600rwhp on waste gate pressure everyday. There is not enough data for anyone to know how long a built engine at these power levels will last, nothing is bullet proof or indestructible, that is for sure. I was just saying that if you want to make 600+rwhp all the time, then you might want to go with a stroker engine, better components, etc. If you just want to make 600rwhp+ on a dyno and drive around with 500rwhp, then you would not need the added expense of a full blown build.

Just my opinion , Hope you can see what I am trying to say.

-George
GT Motorsports

 

Point taken, time and who the owner is will tell what we can expect of those set-ups regarding reliability. I wish most people would post problems in general (not picking on you/GTM you know I respect you guys), many try to stay hush hush on that subject.

 

I do agree with you on the fact that a 700rwhp car that is "babied" will last longer than a 500rwhp car that is driven hard or to its limits, so it is hard to judge how long and engine will last, and if it did last that long if it is because the components are truly better, or the car wasn't drive as hard as it could have been.

Only time will tell, one of the 4.2L GTM stroked engines/APS Extreme combos is a full blown professional race (drift) car, this car will see more abuse that most cars on this forum. We will see what happens

-George
GT Motorsports

 

I have a question for you, from what I've read and seen the 4.2 stroker runs very hot. Thats why you've guys have made that radiator fan assembly. Heat creates problems, to me that wouldn't be a very reliable setup for long term use, aggresive driving or not. Am I wrong in believing this. I'm not trying to start anything, just gaining info. I think its great that your here offering your knowledge, and opinions.

 

A lot of the reason it runs hot is because of the massive APS intercooler blocking airflow to the radiator, but yeah, the sleeves also add some extra heat

 

The 4.2L stroker isn't what runs hot, ANY sleeved VQ will run hotter than a non-sleeved VQ. It will run hotter (about 5-7 degrees Celsius) We made our fan kit to help any of the many sleeved VQ motors out there, or any other VQs that are tracked and see high temps.

The minimal heat difference will not be much of an impact on a daily driven car, plus our Fan kit and proper radiator will take care of the heat issues.

You do bring up another reason why it would be better to run our 3.8L stroker vs. a 100mm bore on sleeves, since our 3.8L stroker is not sleeved, it will run cooler.

Hope this helps,

-George
GT Motorsports