When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I took the car to a show, and we put it on VMP's Dyno jet. I thought she was going to make at least 250 rwhp. However we only made 211 rwhp and 215 ft lbs... Anyone got any ideas? Previous owner told me he put the stock computer and injectors back on since it wasnt running well at all.
I am really looking to build the car to get about 350 rwhp out of her. I am in FL at sea level, and I am just a little slower than most of the guys on the street and track around here. This isnt a race car, it just needs to be able to do a little pull every now and then or a 1/4 pass and not get embarrassed.
Car is a 1987 Turbo 2. It has to my knowledge a stock motor, stock injectors, stock ecu. HKS blow off valve and front mount intercooler. I am not running power steering, or ac, or the clutch fan, so nothing on the belts besides water pump and alternator. I also have Racing Beat exhaust, and it appears to be 3" most the way out. Including catless downpipe.
87 RX7 Turbo 2
Last edited by AutoMafiaRacing; Apr 19, 2018 at 11:35 AM.
With power and torque dropping so early, there is no reason to rev it out to 8500! You're better off short shifting and falling back into the meat of the powerband. Those number's aren't unreasonable for a stock turbo. You may be able to hold power out a little further with an electronic boost controller, but it's hard to see much without a boost plot. I'm guessing boost is falling off pretty hard due to the stock turbo.
With power and torque dropping so early, there is no reason to rev it out to 8500! You're better off short shifting and falling back into the meat of the powerband. Those number's aren't unreasonable for a stock turbo. You may be able to hold power out a little further with an electronic boost controller, but it's hard to see much without a boost plot. I'm guessing boost is falling off pretty hard due to the stock turbo.
I agree. I hadnt dyno'd it previously, so now I know that haha. I wont rev her past 7k rele if im racing.
I am just trying to figure out why it was such a dramatic drop off. It hits 5k and literally falls in the toilet haha. I thought it would keep making power.
211whp is not bad since factory is rated 181 flywheel hp. The car is basically stock with a bigger exhaust. My friend's s5 t2 running 10 psi stock engine and intercooler, catless exhaust made 228hp on a dyno pack.
Those numbers seem pretty realistic for what is essentially a stock turbo II. Unless I'm looking at the graph incorrectly, it appears that peak power was at 6.07K rpm and the power is tapering off after. It's not exactly falling on it's face but it seems like boost pressure is dropping off (boost leak?). Regardless, I'd look at getting an Rtek, larger injectors, and a boost controller if you're just wanting a little more kick in the pants. If you're wanting to make upwards of 350whp, you'll need a new turbo, injectors, a much better ECU (imo), and a larger fuel pump.
Bear in mind, most of my rotary experience is NA so I'd take it with a grain of salt.
211whp is not bad since factory is rated 181 flywheel hp. The car is basically stock with a bigger exhaust. My friend's s5 t2 running 10 psi stock engine and intercooler, catless exhaust made 228hp on a dyno pack.
I have full exhaust and a FMIC. So Im making less power than his stock car?
Those numbers seem pretty realistic for what is essentially a stock turbo II. Unless I'm looking at the graph incorrectly, it appears that peak power was at 6.07K rpm and the power is tapering off after. It's not exactly falling on it's face but it seems like boost pressure is dropping off (boost leak?). Regardless, I'd look at getting an Rtek, larger injectors, and a boost controller if you're just wanting a little more kick in the pants. If you're wanting to make upwards of 350whp, you'll need a new turbo, injectors, a much better ECU (imo), and a larger fuel pump.
Bear in mind, most of my rotary experience is NA so I'd take it with a grain of salt.
You are reading it wrong, that would be the torque curve you are seeing, she makes the most torque at 4750-6300, HP Peak is the lower line and solidly at 5250.
Yeah I would be perfectly happy at anything from 300-350 rwhp. The car would be much faster, and much more fun. Getting beat on a little street pull up to the speed limit by a 328i is a little embarrassing.
sounds about right for a stock car, if you have a full RB exhaust you will want to be careful you dont blow that engine with stock tuning and injectors.
I'd probably take a closer look at that exhaust. Is the stock cat in place still? That's definitely a bottleneck if so.
After that I'd look closely at the intake hoses. Are they all stock? Sometimes those plastic pipes will get a hairline crack that's nearly invisible until it's pressurized.
After that I'd get a boost and AFR gauge...maybe toss in a water temp one while I'm at it.
You are reading it wrong, that would be the torque curve you are seeing, she makes the most torque at 4750-6300, HP Peak is the lower line and solidly at 5250.
Yeah I would be perfectly happy at anything from 300-350 rwhp. The car would be much faster, and much more fun. Getting beat on a little street pull up to the speed limit by a 328i is a little embarrassing.
Interesting, the graph you provided states:
Max Power= 211.63 at Engine RPM= 6.07 (tapers off after)
Max Torque= 215.04 at Engine RPM=4.84
Regardless; a full exhaust, BOV, and front mount aren't going to work miracles and net 250whp. The stock turbo peters out around the 5-6k mark and efficiency decreases. As others have mentioned, it would be a good idea to give the car a good once over to eliminate any possible boost or vacuum leaks.
That said, there are people who've made ~250rwhp on a stock turbo, stock port motor. However, this requires fuel mixture and potentially timing adjustments (ala ecu tune).
sounds about right for a stock car, if you have a full RB exhaust you will want to be careful you dont blow that engine with stock tuning and injectors.
FULL RB exhaust and FMIC... That will blow a motor?
Originally Posted by Natey
I'd probably take a closer look at that exhaust. Is the stock cat in place still? That's definitely a bottleneck if so.
After that I'd look closely at the intake hoses. Are they all stock? Sometimes those plastic pipes will get a hairline crack that's nearly invisible until it's pressurized.
After that I'd get a boost and AFR gauge...maybe toss in a water temp one while I'm at it.
I do have a boost gauge, I for sure need a water temp and a wideband though. It has a front mount intercooler.
Interesting, the graph you provided states:
Max Power= 211.63 at Engine RPM= 6.07 (tapers off after)
Max Torque= 215.04 at Engine RPM=4.84
Regardless; a full exhaust, BOV, and front mount aren't going to work miracles and net 250whp. The stock turbo peters out around the 5-6k mark and efficiency decreases. As others have mentioned, it would be a good idea to give the car a good once over to eliminate any possible boost or vacuum leaks.
That said, there are people who've made ~250rwhp on a stock turbo, stock port motor. However, this requires fuel mixture and potentially timing adjustments (ala ecu tune).
I take it back, your sir are correct. I pulled out the sheet and looked at it again, and not the picture. So I guess that torque falling off must be the turbo hitting its efficiency limit. So 4k-7k is pretty good above 180 rwhp. Not too bad.
So basically you guys suggest a tune, and injectors, and a bigger turbo to get over the 300 rwhp mark.
FULL RB exhaust and FMIC... That will blow a motor?
yes, the stock ECU is pretty limited in what it can compensate for, so your setup is pretty close to the edge of not being safe
Originally Posted by AutoMafiaRacing
So basically you guys suggest a tune, and injectors, and a bigger turbo to get over the 300 rwhp mark.
the highest i've ever seen on a stock turbo is about 250rwhp. for 300 you need a bigger turbo, and fuel pump, and injectors, and some kind of ecu to run them, and then tune it.
