My car puts out 402 lbs of torque at 3100 rpm. When it hits it sets you back in the seat. I have a stock turbo with a 10.5cm hot side. Everything has been ported to improve spool up (including the head). It you want torque at low rpms you will probably need to stick with the stock turbo or maybe even a green although most of the graphs I see they push the torque curve out at least a 200rpm.

Shad

 

Well...a stroker kit will make monster torque with the stock turbo in that range. Do you "NEED" it? No. But it's an option if you got that money.

 

vee21: The alkie isn't spraying yet at 3100 RPM is it? Your car proves the point that it's hard to beat the stock turbo for lowend torque numbers. This is a great setup for the street on the stock block and turbo. Congratulations

 

This is on Buschur Racing's low Mustang Dyno. 2.3 Stoker, 20G-9-5, Meth, Revolver Cams.

408 ft-lbs and 359 hp. Meth starting around 18psi.

 

The meth starts to spary at 14psi. At 3100rpm I am at 28psi and it is spraying like crazy.

 

vee21, you wouldn't happen to have a dyno graph you could post? If you have over 400wtq @ 3100rpm, then I'd expect you to be seeing around 350wtq at like 2800rpm or so - I can't figure out how you're achieving that (unless you're talking about 5th gear... )

Did you see significant gains in spool or low-end torque by porting the head? I always assumed that was more for top-end power...



Sparky, I hear what you're saying about the WR-9, but I feel like it wouldn't be that much of an upgrade over my IX turbo to justify the $$$ and labor.

Do you know if turbos that spool earlier than stock (i.e. BB 16g conversions, WR-9, 6.5 TME, etc) also tend to die off earlier in the top-end than stock?


FWIW, I did talk to Robert at FP several months ago regarding an FP Green with a 9.8 which he felt should spool a little earlier than a normal FP Green but would also give up a little top-end. (hmmm... that would equal a stock IX turbo then,right? ) I cancelled my order after thinking it over...

 

I will try and find to tonight and get it posted, the 400 was done on a dyno jet in 4th.

I have my graph from Buschur's, it is a 3rd gear pull. I put down 350wtq at 3700rpm.

The ported head did spool the turbo quicker. I am sure it was because of the improved flow of the head which allows for more air to move over the hot side of the turbo. The head moves more air at all rpms so I picked up tq& hp at all rpm levels.


Shad

 

OT but Muddduck what kind of power are you making right now?

 

20glt.

 

350whp/345wtq on pump 93 spiking to almost 24psi on boost guage... peak torque hits at 3800rpm in 3rd gear.


I'm trying to get my tuner to email me my dyno graph so I can post it up...

 

I inquired about the UK treatment you mentioned and it's about $4000 for everything. Too rich for my blood.

I do agree with your statement about our UK brethren and their philosophy. They do some wild stuff over there.

If you don't do alky, the option of a green with a 9.8 hotside for quicker spool might be suitable. FP mentions on their site about a potential 9.0 hotside for even quicker spool. Obviously, you'd be giving up top-end.

I have found no one stateside that will convert a Green to BB.

You and I appear to have similar goals. There is a Green alternative in the works by another vendor here. I am prepared to wait it out for the precise turbo I want.

 

IX's can make peak torque at 3200 if you want them to just by really working the MIVEC carefully and thoughtfully. An Evo 4 hotside is 9cm, obviously the 5-8's had 9.8's and 10.5's. I can think of at least one Rally car that has messed around with the Evo 4 housing. Then there is the rally specific 15.5GK which is designed for high boost at the lowest possible rpm.

I have logs of cars I have done that make 25psi at 3200 and max load (and theoretically max torque) at 3800rpm. If the boost had held constant and not gone to 25.8 (knock free I might add) peak torque probably actually would have been at 3200. For those that understand the ECU, it hit 290% 2 byte load at 3200 and 292 at 3800 with a slight taper in load in between those points. The car was equipped with a stock turbo, pump gas (93 octane), and S1's.

Here is the log for those interested:

http://files-upload.com/332066/mk88.csv.html

JB

 

^ yeah, the easiest way to get more torque @ a lower rev = mivec tuning

2nd way to get immediate throttle response = 65mm tb

3rd, apply the dejon tool fix to your bov & you will get more transient boost response. not sure how the bov cooperates during city driving = high boost & low throttle conditions, but i think it should be fine.

lastly, try a 9.8 hotside = but i think this would be hyper sensitive to throttle input with the above mentioned mods.

mivec tuning, bov mod & 65mm tb is the easiest way to go.

if you feel that isnt enough, go 2.4L route

 

2.3L + TME turbo (with rare 9.0 hotside) + Meth will get you some serious torque down low.

 

I wouldnt spend the money on a stroker if you are going to still try and use a stock turbo. The car would be too lopsided and lose alot of its fun (revving it up high) at least in my opinion. The 15.5GK would probably be the best overall choice if you were going to spend the money on a new turbo, ebay/overseas shop/Rally guys for a 9cm as the next option, and of course cheapest is spend some time with the MIVEC.

Its all about what the overall goal is and how long you want it to last. Remember WAY BACK WHEN, Dynoflash had that car run a 36psi spike on the stock turbo on meth and it made 512ftlbs at the wheels? It wouldnt last long (internals and turbo both) but I am sure it was lots of fun.