columbian frldy

How does everybody feel about the stroker kit boreing out the engine to 4.3?
Anybody seen numbers with high compression all N/A and low compression with F/I?
Also, do you think it is worth the money?? Costs roughly around 8 g's not installed I believe


http://www.aebsracing.com/products.p...ct=vq35stroker

shopdog

Not worth the money. I'd estimate a 65 hp power increase NA, with proper tuning but no head work. Maybe a 110 hp with cams and porting. For $8k you can get lots more power than that by going FI.

They do use high quality pistons and rods, and the sleeves appear to be high quality as well. Reliability should be good. But you really wouldn't see the benefits of that unless you were going to go FI, and you can get just the forged pistons and rods for much less than they are asking for the kit.

johanna1

iTrader: (1)

It would be worth it because then you have more room to work with when you go FI. I know a couple of people that got a stroker kit for there mustangs and then FI it and they are running some mean hp and tq.

Daking350z

In a nutshell, unless you plan on running 1000+hp and being a pro drag car...NO..

adanande

HEy !! why only 65 horsepower/ If you calculate the same 80 horspower per liter then 4.3 liters will be around 65 horsepower but they add compression and it should add a lot of tourque down low. With the 11.0 to1 or 11.5 to 1 compression gains should be about 90 orsepower.

But on that note i think that the price is with installation and you can get the parts for cheaper.

With installation in mind its not as bad, but still 8 grand is a lot but you won't blow your'e enine and if someone really values N/a then with bolt ons it will be around 400 plus horsepoer because of the increased displacement giving the car more mod poetential.

Aps engine n/a engine kit with tilton flywheel and 350evo gears will be super sleeper. Not even Police will know what is under the hood and it should be street legal too.

porsche gt3 soup.

Just get a gruppe m intake and some headers, aps exaust and you'll se whats up.

But with F! it is definetly worth it beacuse if someone wants to build their engine, with sleves and rods and a crank anywyas then this is a bargain. I'm pretty sure its with installation. yeah nles you want a 1000 hp turbo or supercharged drag racer Its far from a bargain.

shopdog

[QUOTE]Originally posted by adanande
HEy !! why only 65 horsepower/ If you calculate the same 80 horspower per liter then 4.3 liters will be around 65 horsepower but they add compression and it should add a lot of tourque down low. With the 11.0 to1 or 11.5 to 1 compression gains should be about 90 orsepower.

Yeah, but you'd either have to run race gas, or richen up the mixture and retard the spark so much to run pump gas that you'd negate any hp gains.

But on that note i think that the price is with installation and you can get the parts for cheaper.

Lots cheaper. Z1 will build you a complete engine with forged internals for $6000. In other words a full race ready engine to drop in your car. Then add the twin turbo kit of your choice and you'll make lots more power, and do it on available pump gas.

mchapman

iTrader: (1)

Has anyone on the forum got this yet?

97modman

$6000 for a brand new engine with internals or your engine with internals???

UsafaRice

Yeah, as much as I`d like for this to be true, I don`t even think you can get a new, plain, engine from Nissan for that much.

The 4.3 L 11.5:1 CR motor could make about 450 at the crank if things are put together right. AEBS knows what they are doing and have gotten more power than the Z makes stock out of a Honda motor that`s half the size (NA of course).

11.5 is really not that bad. Look at some of the CRs for Porsches and Ferraris. And I could tell you that someone who just paid $95K for his GT3 is not going to want to have to run race gas every fillup.

Another benefit is that the NA, large displacement, high CR route, doesn`t add weight to the car.

shopdog

They're saying that's exchange.

Darren

I'd be concerned with piston wear as a result of the longer stroke, higher pistion speeds, and possibly shorter skirts to keep the pistons all lined up nice and pretty

shiva

The 11.5 CR N/A version isn't worth it. To extract any N/A HP out of the motor, you'd need to get head work done. And to keep things safe and reliable, you'd need new pistons and rods. At that point, you might as well have spent an additional $8000 for a TT kit to get ~700rwhp, as opposed to ~400rwhp.

Modding this car cost effectively is a tricky proposition. If you stay N/A, you won't make much power while staying cost effective; without getting expensive stuff like cams, you might be around ~250/260whp. You can get a supercharger for around $6000 installed/tuned and make about ~380whp. A $7000 TT kit, by itself, is both unreliable and expensive...I wouldn't trust ~410rwhp with our weak rods. You can get a rebuild done, and then you are getting decent hp / dollar..of course, we are talking major $$$ then. Finally, you can get a 4.3 Stroker + TT kit, but that really hasn't been done yet.

Damn...if only the stock pistons and rods (particularly the rods) weren't so wimpy, then F/I for ~430whp (where I'd like to be) would actually be somewhat cost effective!

MIAPLAYA

iTrader: (3)

I believe for $8000 you get your choice of compression ration 8.5:1, 11:1 11.5:1 with brand new pistons, rods, etc. Sleeved bottom end..I would say its worth it if you are going to run some really high boost to go for the 8.5 to 1. If you think about it the motor Z1 is selling is the same thing sans the increase of displacement. I mean can you imagine the APS kit running lets say 14 PSI on a 4.3 L VQ. Good God you could make the Earth spin backwards.

azrael

precisely.

the piston speeds generated by the really long stroke make me shy away. I want nothing to do with it. 9:1 CR on the stock displacement sounds much better to me.

3.5L is plenty to create some torque down low, and once the turbos spool, the displacement ceases to make a big difference. I'd much rather spin to 8000 RPM and have the power up high than have 0.8L more displacement.

Nathan

Some contradictions here.
Your worried about the piston speed that comes with a longer stroke but but the piston speed that would result from high revs is not a concern?

thunder0880

iTrader: (10)

I doubt it.

350Z-VDC=Bandit

AEBS claims 450 crank hp with stock heads cams. I would be happy with a 400 hp na z on stock gears it should rip mid to high 11's. add some bolt ons and tune it and you will be looking at 450whp compared to a greddy TT kit thats 6g's and another 2-3 to install and your getting 70 more hp and no chance of detonation and it looks like a good deal to me.

Zoomy_1

Accually, you can ease some of that with rod length as well.

Piston speed aside, you know that the stresses induced on the main caps and wrist pins by RPM is exponential right. I forget the math but it's something like 800rpm@above 6,400 acually doubles the loads on your rod (hence rod stretch from missing shifts).

I'm not flaming you but it's been proven, is you make the same mod to two engines the one with the most displacement WILL make more power.....everytime. Like you said once the turbo spools displacement dosen't matter so much. But the extra exhuast volume from a bigger engine will make the turbo spool faster. To me it sounds like a pretty good formula for BIG power...all the time.

That's what I would do if I was a rich man. Than I'd be off hunting every fast American car I could find that didn't take a Z very seriously. It would be a case of the rich getting richer.

azrael

My apologies, I need to clarify. I intend to build the engine in my car to withstand a higher rev limit, and then select a cam that will allow for that extra powerband to be useful. I road race my Z, and the wider powerband would be infinitely useful. The gearing and powerband with the stock motor causes shifts just before a corner, which is annoying when on a roadcourse.

Given that I want a higher rev limit, I don't want to increase stroke as well. The combined piston speed is what would be uncomfortable. As you correctly pointed out, raising the rev limit would increase piston speed, and stroking would do the same. Either one is somewhat concerning, but the combination is definitely not something I care to risk on a car I still drive on the street.

To me, the gains from raising the rev limit far outweigh the low-end torque the 4.3L stroker would provide.

Other data I'd consider is the rod/stroke ratio:

Stock rod length: 144 mm
Stock stroke: 81 mm
4.3L kit stroke: 90 mm

Stock rod/stroke ratio: 144/81 = 1.77
4.3L kit rod/stroke ratio: 144/90 = 1.6

The stock rod/stroke ratio is very, very close to the "magical" 1.75 ratio that is considered the best real-world compromise to achieve good piston speeds away from TDC that match the speed of the flame front from combustion, and also to keep the rod angle nice to reduce friction from side loading the pistons.

Just some food for thought.

In your favor, I calculated peak piston speeds for an 8000 RPM 4.3L stroked VQ, and they were still less than the peak piston speeds for the S2000's 2.0L F20C. Maybe with forged components it wouldn't be as terrible as I thought? Who knows. I'd love to talk to an engine designer to get their thoughts.

Matt

350Z-VDC=Bandit

call aebs they have some good tch guys. the rods and wrist pins are the only parts I would worry about the z actualy has a stronger main bearing cradle than a z32.