question for gsxracer

[smokeurass]

I noticed that you and chad both have the same 1/4 mile E/T's. Then, chad also has about 100 more hp than you. Is this some difference btwn the 1g and 2g cars, or are you just better at drag racing. OR....does your tq peak at a higher rpm so you take advantage of gearing while chad cant?

[JoeWagon]

if you are referring to 95 GSXRacer's 400whp, remember that it is pump. It's possible that the other car you mention (i dont know who chad is) was power on race fuel. If that's the case then GSXRacer's car would be closer than 100hp away. i won't guess at the power from pump to race.. but it might be 400-500 (plus he might run more boost).

[kjewer1]

EVeryone is correct. Chad was on race gas and 31 psi, I was on pump gas and 25 psi. Our cars are pretty well match, with the exception of his FRH intake manifold. With my stock manifold i would still have expected about 480 hp on race gas. Chad also is less experienced on the track than I am, which explains the difference in our mph but same ET, as you suspect. I'm not the worlds best driver, but I have hundreds and hundreds of passes, in my car. Hell, I jumped in Joe Gs car (on the site as well) and beat his 12.2 with a 12.07 on my first run. The kicker was it was a 1.99 sixty foot! Could have been 11s, if we had more time. To adress the TQ question mine would actually peak lower than his, since his manifold will push the TQ band upward. Otherwise you both pretty much nailed everything

This year chad and I will be much more equally modded. Actually, I will have hte 2.4 liter in, and he'll still be on a 2.0 (my old SBR stage 2 essentially). But he just lightened the car up a good bit, and will likely still ET and trap better than me.

[JoeWagon]

im relieved that i didnt assume anything wrong, be sure to say so if you notice i do in any post.. trying to learn as much as possible, not have a big ego.

ANYWAY, can you tell me more about what your 2.4 plan is? are you going to buy another block and give yours to Chad, or do you mean that he is already on an SBR stage 2 block (i probably could check the site for that one :P ) and that you are stroking/boring to 2.4? Also lastly can you tell me your estimated power (or stability advantage) with the same mods. dunno if you are getting better internals for it. thanks

[kjewer1]

I am still keeping my block. I had the number 2 spark plug fall apart, and part of the prcelain damaged the cylinder wall. Since I have to bore out the cylinders another 20 over, the 3 good pistons are no good. I am going to be using the same eagle rods, and stroker pistons, I believe Ross as well, but couldbe weisco. So with one new piston, my whole rotating assemly is good, and it saves a lot of labor. I need the new crank anyway. So long story short, its a bored/stroked 2 liter. With just the increase in displacement (20%) I Expect my airflow to increase from ~45 lbs/min to about 52-53. Since each pound is 10 HP, it actually fits in well with the 70hp gains people have seen. TQ goes up by well over 100 ftlbs though. Add in the manifold (another ~3 lbs), and I should be able to make some nice power gains at the same 25 psi, never mind 30 It goes against everything we talked about in the low rpm TQ vs. high rpm TQ thread though, since they generally dont want to rev as high as the stock 2 liters, but this is a daily driver. The force on the internals goes up with the square of the increase in RPM. Not worth the reliability risk of a high reving motor with all the fun I lke o have on the street. For a race only car i most likely wouldnt go this route. Not to mention it will spool my turbo at less than 4k rpm, rather than about 4400 I get 25 psi at now. There are several other mods I'm doing to ake this all a well matched system, but I'll talk more about those when the car is running again.

[JoeWagon]

good luck with that, sounds like it will be something fun to get used to.

2 more quick questions though:
is that stress=rpm^2 an actual equation or is it an estimate and statement of how important rpm's are to stress factor?
also, was it you that had the engine that COULD go 10.5k but set it lower for practical reasons (keep in power band)?

[kjewer1]

[quote=JoeWagon]2 more quick questions though:
is that stress=rpm^2 an actual equation or is it an estimate and statement of how important rpm's are to stress factor?[quote]

You cant get the actual amount of stress, but you can get roughly how much it will increase, with rpm. Stress will go up with the square of the rpm increase. I read that a 10% increase in rpm equals 25% increase in stress. I'm no mathematics expert, or I would attempt to explain how to figure out what a particular rpm increase would do to stress. Perhaps some one else can put the above phrase into an equation so it makes some sense. IF not I will try to figure it all out and then explain.

also, was it you that had the engine that COULD go 10.5k but set it lower for practical reasons (keep in power band)?

The rpm that a motor is "safe" to go to is determined largely by the weight and strength of the crank, rods, and pistons/pins/rings, and the rod ratio. A long stroke motor has a bad rod ratio and there is a lot of sideways intertia relative to the length of the stroke. They generally dont rev as high safely. But there are things that can be done about that. Magnus motorsports takes thier 2.4 liters to 8500 rpm. To rev really high, do the opposite. Destroke the motor 10k rpm in a 4g64 block with 4g63 crank (2.1 liter) should be a pice of cake. But you'll need intake exhuast, cams, turbo, etc that will work at the high airflow rates that wil go with rpm that high. VE will be tough to keep up. But based on the fact that making torque at higher rpm makes more power, it would be worth it for an all out race car. The trick with dSMs will be to get a tranny that will shift that high.

[95_GSX]

Damn kevin you are just full of good information. i am glad you take the time to share all of it with us. thank you.

[NeonblueEclipse]

ya dude
confused the hell outta me but after taking the time to read it fully plus the website you provided added the extra little bit
thanx man i finally learnt sumin useful

[95_GSX]

Originally Posted by NeonblueEclipse

ya dude
confused the hell outta me but after taking the time to read it fully plus the website you provided added the extra little bit
thanx man i finally learnt sumin useful

now go take an english class.

[EclipseRST]

[Nalfein]

just a quick clarification here....
for my application anyway...

i havge a 97 gst. I'm not planning on going nuts, I just want to make about 350 hp (16g, fmic, injectors... yada yada yada). I did however want to upgrade my valvetrain so I could rev to 8500 to 9000 just for kicks... you know I thought it would be cool to rev like an s2000. This is a street car not a race car (though I will take it to the track the odd time) but are you guys saying that raising the rev limit will make my engine less reliable and stress the hell out of my internals.

Despite the cool factor, this isn't worth it on a daily driver is it (reliability wise).

Thanks
Matt

[kjewer1]

If you dont have the correct setup, it wont make any sense to rev that high. It will be awefully slow at least. The 16g wont keep up with the motor at high rpm, and you'll need cams/manifold/turbine housing that will lend themselves to high rpm. Not worth the effort unless that is part of your plan anyway, which doesnt seem to be the case for you.

[Nalfein]

k thanks a lot
Well i guess I can be happy that I just saved a shitload of money