how fast is your turboII? i have a series5 TII (na>t2) and i'm running about ~6lbs of boost (7psi bleeding to 5 by redline). i havent been able to get to the track since its closed for the winter, but i've raced a few of my friends (most which have low 14 second cars, a few 13 second cars)
i can beat the 14 second cars but i'm still behind the faster ones (turbo miata, modded integra typeR)

i plan on running 11 lbs after i put my walbro in. i have an safc and i think that (tuned) + a fuel pump will be good for ~11 lbs or so on pump gas. my question is for some of the guys who are running a little more boost on the stock turbo... how fast are you?

 

You will probably need larger secondaries to run 11PSI+ safely. I don't have an S5, but I know by my numbers that 2200CC's of injector would not be enough for me at 9 PSI, much less ~11 But I am not real sure how much of that might be compressor wheel related also.


-Robert

 

really? we were running 15lbs on my friends s5 TII (it has a haltech) but still, those 550's can support more than 9 lbs... you sure with 550's and an safc and fuel pump cant handle 11 lbs?

 

with just the walbro on 10 pounds I think scott ended up leaning out some places with his safc actually. 550's and the walbro should make 11 psi, get it tuned on a wideband.

 

Stock front mount at 11 psi is alot of intake heat, you are going to want real low 11.s on your A/F ratio at torque peaks.. I know that 4 550's will not do that on my setup at 9, much less 11. Thats all I am saying ..

at 12 PSI on my setup i have points where my S--AFC is in the + with 3440cc's of injectors, so you be the judge ... but like I said not sure how much of that is related to the compressor wheel I run compared to yours .. along with other mods.

Also, just cause injectors can 'do it' does not mean they are at a safe duty cycle while trying to push that much fuel.


-Robert

 

On my dyno A/F numbers were in the mid - low 11's. I think you're going to be using a lot more fuel since you're throwing in a lot more air than a stock turbo. I wouldn't reccomend over 11 pounds on the stock fuel system with the walbro, I still strongly urge everyone to get on the dyno with a wideband and find out exactly what there a/f figures are. I agree with your last comment.

 

I have a 91 TII and my car completely stock, down to that sweet radio, ran a 14.5 the day after i bought it. Last time i took it to the track i was having serious problems so i didnt run it, however a freind of mines rx7 that i could beat ran a 13.2. When the track opens, we'll see whats next. Im shooting for a 10 by this summer. Almost there!

 

We missed your mods list

 

10s on a comletely stock car? really?
care to explain on how you will achieve this miracle?

 

i got a 88 TII... sure not S5, but its better than S5 i got a S4 motor built with 93 rotors, a stage 2 street port, stage 1 exhaust port, 2mm 2 piece seals, stock primaries, 720 secondaries, S5 exhaust manifold w/ S5 turbo, stock TMIC, 3" RB DP, 3" straight pipe(ie no cats mufflers nothing), and my car was pulling 12's(before the rebuild with stock ports on a JDM S4 motor with S4 Rotors)

 

rockets

 

so how about some people that just have an intake and full exhaust?

 

dont you have a T04 hybrid? 11 psi from a t04 compressor is way more power than 11psi from a stock ht18...

 

How is 11psi more power from a different turbo? Isn't 11psi, 11psi??

 

Rpeck, you can't run 11psi on 2200cc of fuel because you have a comparatively gigantic compressor wheel. it is flowing a hell of a lot more than the stock wheel and so more air=more fuel. 9psi on the stock turbocharger is not the same as 9psi on a hybrid.

 

Thats what I was trying to say above. I am not sure 'how' much of a diference is invloved with the different compressor wheel ... but I was just using that as an example. I guess there is more of a diference than I thought ... But I still don't think 11 PSI on stock fuel is smart.

 

11psi on the first turbo will push more power than 11psi on the 2nd.

 

lol.. i never said i was still stock. That was last year WHEN the car was stock. The day after i bought it I wanted to run it at a drag strip to get an official time slip for it completely STOCK so i can see my progress. That was last year. After a few upgrades on the stock engine I was in the low low 13-high 12 bracket, i dont have a timeslip to prove that because my exhaust manifold about fell off on my way to the strip. I did make 1 pass at 13.5 with half my exhaust shooting out the side of the manifold and not into the turbo. Before and after that i could regularly beat high 12 second cars. Its just that day i had some serious problems.

as for shooting for a 10 second slip by the end up this up coming summer. The mod list is pretty big and i dont really feel like typing it all out because there are a few more parts i need. I'll just post this...




ps. that was the old engine and we were doing a mock up of the manifold and checking fitment issues. Since then the motor has been changed to a s5 13bt with s4 rotors, large street port, exhaust posting, extra solid dowel pinning, 3mm cgi seals, 3rd gen corners, oil passages bored .. yadda yadda ..

However im thinking of going with the new t04z as soon as i can find more specs on it. Looks like a really nice turbo.

 

But it's not.. 11psi on say a T66 flows more CFM's than a say a To4b at the same boost level. just as an example. That To4b might have to run 16psi to flow the same amount of air as what the T66 is flowing at 10psi.

 

My car should see the track this year now that I have a wideband to tune with. As long as all goes together well and I don't find any more unexpected expenses in my near future.

 

yeah its not about air PRESSURE its about air FLOW. common misconception with boost/turbos

 

pocketpool...

 

Jacob, on my car, i run 720cc secondaries on a stock fuel pump, stock ecu, and stock turbo. On average, i hit 11-13psi daily and it runs smooth and gets plenty of gas. Very quick for a stock turbo. No, sorry i dont have a 89-91 t2, but last time i was at the track i ran a 14.2 @97mph at only 8psi. Now i'm sure i'd be in the high 13's.

 

you also have a series4 so can run a little more boost all other things being equal.

 

Untuned with low compression I ran a 13.@102. My MPH was good for a low 13 though with a good launch. That was with the stock catback as well.

Now I have a fresh rebuild with a large streetport, going to get full 3" exhaust and tuned on a dyno and am looking for mid 12s hopefully.