New Dyno Results

fturner

Registered User
I went down to see Dave this weekend and run the car on the dyno. I've attached a chart that shows what the car did last spring before the cam and what the car is doing now with the cam, and a couple of other mild mods that will help to support making more power.

In the spring the car was virtually stock except for a almost non ported '94 blower stock 90 sc pulley, a 75mm TB, 76mm MAF, and 42# injectors and she peaked at 221 rwhp @ 4586 rpm's with a 289 rwtq peak as seen on the chart.

Now the car has a cam, a ported blower over driven at 10%, and a few issues. Before I show the numbers here's the issues.

1. A very crappy exhaust system which includes the stock 2-1/4" newer style center section that goes under the tank. This time though the cats where gutted, and there is a chance that that can hurt performance more than the stock cats in good shape, but not proven.

2. When we pulled the blower apart to port it, I got to see the cleanest, most polished rotors I have ever seen :eek:... they looked gorgeous... but 1 problem. This meant that the coating I knew was there earlier this year was now sitting in the top of my intercooler. Almost all of the coating had come off. Now the blower was less efficient and I had a partially blocked intercooler. The good thing though, the porting job was beautiful :D, so to take advantage of that I need to order up some coated GP rotors.

So with the above in mind and the car running good otherwise the dyno pulls proceeded. (BTW the car was running 91 octane). Because the intercooler was partialy blocked and the blower itself was down in efficiency, the ACT's skyrocketed each run so Dave felt it was better to cut the run off at 4500 rpm's, as so much timing was been pulled by that point the car was losing power.

The car still made 247rwhp at 4471 rpm with a 316 rwtq peak. Thats a gain of 26rwhp :).

Because of the issues above we feel there is more in the car and that will show up when I sort out the exhaust, and deal with the rotors.
Also goes to show that you can still have a totally stock looking car that can run pretty descent power ;) and not have to rob a bank to get there.
 

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Congrats Frit. It will be neat to see what she does when your issue's have been addressed. What do you think, 260 265? Keep us posted!:D

Stephen
 
Congrats!. Stock IC still? I'd think the 10% with a stock IC would be the main cause of high ACT. Seems when you OD these 94/95 blowers the coating strips right off. This has happened to myself twice thus far. I didnt notice a difference with my GTP rotors although Im sure it did something..I also dont know where the coating went because I didnt find it in my IC!!!!!
 
Still the stock IC with the fan on it. We where discussing the OD with coated rotors and I'll be dropping back to about 5% OD when I get them installed.

What we where seeing was boost staying around 13.6 psi and was steady until about 3800 rpm's and started climbing to hit 15.1 psi by 4300 rpm's then actually started dropping a little. The ACT's started at 92F and where slowly rising and was at 111 F at 3800 rpm's but hit 138F by 4500 rpm's. Because the IC was partially plugged we started to outflow it at 3800 rpm's which increase back pressure is my guess.

The reason I can say this is the previous datalogs I have, the car ran steady boost all the way out to low 15 psi at 5500 rpm's with a slow increase of about 1 psi through the whole range which tells us the motor was nicely balanced with the blower and the cam was allowing it to breath nicely. I could probably dig through my logs and find just when I lost the coating, which I think has only happened in the last month or so come to think about it.

BTW I made that power running under 15 psi ;).

Frit
 
Well done Fraser,
Those are some impressive numbers. Looks like your hard work is starting to really pay off. I think what you are doing with the car is great keep it up.

Drew
 
I had a 10% JS pulley on my last setup with a DIC from Ken W. On the Dyno I made 260. It was still getting real hot and I was getting a lot of belt slip. Just seems like 10% is too much even for a ported 94/95 blower, new belts, and HD Tensor springs.

It made me nervous driving her hard. Well the next car has a 5% pulley and I think that is the way to go with these blowers.

Will you go with a DIC or fab up a FMIC?

Stephen
 
I'm going to stick with the stock IC for now as I don't think I've over run it yet and I have a few tweaks to make to help it do its job. I don't want to give away too many of my secrets yet :p but I'm following a different theory. Dave has been a great help in working on this project with ideas etc.

Also, you have to remember that ACT's are going to climb more rapidly on the dyno than they will at the track because of the lack of airflow. All my datalogs show while I was driving that the single IC stabilizes the ACT's when the car is around 80 mph at my boost levels.

Frit
 
Keep in mind that Fraser's 247rwhp is more like 260rwhp on a 5spd car.

We found that the IC was not sufficent whatever the cause, but rather than focus on the IC (which Fraser needs to retain for the stock look) I suggested he focus on his exhaust. Currently the exhaust system on the car is very poor with gutted cats and a stock crush bent 2.25" single mid section. The exhaust is causing the boost to "creep" up in the higher rpms and is really limiting his power above 4000rpm.

We also would have made a little more power (probably hit 250rwhp) with 93 octane fuel but we were already experiencing light knock with the 91 that was in the car.
 
Keep in mind that Fraser's 247rwhp is more like 260rwhp on a 5spd car.

We found that the IC was not sufficent whatever the cause, but rather than focus on the IC (which Fraser needs to retain for the stock look) I suggested he focus on his exhaust. Currently the exhaust system on the car is very poor with gutted cats and a stock crush bent 2.25" single mid section. The exhaust is causing the boost to "creep" up in the higher rpms and is really limiting his power above 4000rpm.

We also would have made a little more power (probably hit 250rwhp) with 93 octane fuel but we were already experiencing light knock with the 91 that was in the car.

And that's a big part of why the HP wouldn't keep climbing. We know that once the knock sensor starts pulling timing you're done. When my knock sensor was kicking in at 4300rpm the engine just started kicking and smoking.

Certainly sounds like the exhaust is the next thing to change and it also sounds like you're on the right path. 260rwhp is nothing to sneeze at all things considered.

Ira
 
And that's a big part of why the HP wouldn't keep climbing. We know that once the knock sensor starts pulling timing you're done. When my knock sensor was kicking in at 4300rpm the engine just started kicking and smoking.

Certainly sounds like the exhaust is the next thing to change and it also sounds like you're on the right path. 260rwhp is nothing to sneeze at all things considered.

Ira

The motor wasn't pulling timing due to the knock sensor as I had it turned off. Timing was being pulled a little due to ACT's but not much. We were very close to MBT already so there wasn't much to be gained with timing anyway. The big gain would be to reduce blower losses by reducing boost by reducing exhaust back pressure. That is my theory anyway. :p
 
The motor wasn't pulling timing due to the knock sensor as I had it turned off. Timing was being pulled a little due to ACT's but not much. We were very close to MBT already so there wasn't much to be gained with timing anyway. The big gain would be to reduce blower losses by reducing boost by reducing exhaust back pressure. That is my theory anyway. :p

I thought I saw it said the knock sensor was kicking in. Perhaps not, although we do know that is a limiting factor. :p

I also agree that the exhaust will make a big difference as we have seen that before as well. Especially at the power level he is at now!

Ira
 
Earlier this year we talked about the knock sensor being way too sensitive on my car and pulling timing everytime the car ran so to speak. Its actually a little nerve racking playing with timing and knowing that you don't have a knock sensor sitting there :eek:.

Frit
 
Earlier this year we talked about the knock sensor being way too sensitive on my car and pulling timing everytime the car ran so to speak. Its actually a little nerve racking playing with timing and knowing that you don't have a knock sensor sitting there :eek:.

Frit

I dont think mine was even working that day you and DD were tinkering with my car on the dyno. Id rather have a dead knock sensor than an unhooked FPR lmao.
 
Just goes to show you how zip ties can save a motor :p ;)....

Frit

Hopefully if I can get heads and cam on this thing by May, Ill have all the hard to reach ones tied up just incase.:) BTW those are good number Frit, I made 270 ish at TI and 250 ish at Dayton, and ran 13.5. With some new coating and a free flowing IC, Id say you have Mid 13's in that thing no problem. Your stock sized hydroedges might not be up to the task though:eek:.
 
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