I am buying a s5 n/a engine that has been street ported but I was wondering how good of a street port it actually is. Then car was track and ran a 15.8 is that any good? It had a cone intake and a clutch with everything else stock including the exhaust.

 

Sounds like a fairly mild port, or something else is wrong. But I guess with stock exhaust it could be choking it, hard to say.

 

Tell us the MPH at the end of the 1/4, times doesn't really tell you anything if the driver is not good at darg racing

 

what a stock s5 n/a supposed to run?

i dont know the mph at the end

 

~16.5 depending on driver and conditions, could be more or less.

I hit 14.9 on stock port with 155k mile engine. Full exhaust, intake, weight reduction, ported manifolds, stripped 6pi system.

 

Id bet the stock exhaust is the main problem. Get a full headers, high flow cat and cat back systema dn ill bet you drop your times a lot

 

Something is wrong. Most likely the driver. Hell you can run a 15.8 with a header and intake. Something mechanical could also be wrong.

Try to find out the trap speed, that should be able to clear up some stuff.

 

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Streetport + stock exhaust = little gain, correct?
I always thought that you weren't utilizing the potential without a freed up exhaust.

 

that sounds off to me....... 15.8 is only .7 less than stock......... a descent port job should get you in the low 15's...... must be driver error...... or mechanical error...... even with a choked up exhaust, that time should be better

 

The engine is already pulled from the car so when i pick it up how can i test to see if anything is good?

 

mines stock block and it ran a best of 15.75 i could have shaved a tenth or two off that even if my diff and clutch werent on the verge of crapping out (this was also before any of the weight redux in my sig). it realy is all in the launch. dont expect to see your cars lowest times until youve done about a dozen hard launches and realy get the right technique for your set-up down.

get an exhaust and intake on there, a streeport is going to waste without them

 

i say choked exhaust....

 

Stock exhaust really chokes rotaries. I'd bet you would lose at least a second in the 1/4 by swapping in something better. Just adding a racing beat header to my streetported n/a, even though I still had my krusty old stock main cat and cat back, was worth .6 seconds.

 

exhaust...just my .02

 

full exhause/header does alot for a rotary, especially a streetported one.

 

I ran a 15.2 in my stock port s4 with only intake and eshaust. so 15.8 seems slow for the alread higher power s5 + a streetport. with intake exhaust(not cats) and a header you should be able to run solid 14s at least. You may also want to invest in a SAFC or standalone to get the full potential out of your motor since once you add some other mods it will most likely run rich

 

So how come no one mentioned elevation? Here in Utah a 15.8 in a N/A anything is pretty good.

 

^^^ this guy knows what he is talking about!

 

tooshay!!!! elavation is a major role in e.t. times!!!!! kudos to you!!!!