Crappy 1/4 mile slip

[Razor]

I'll call champion and see what they put in the irons.

They put what you tell them. As every combo is different. Again huge mismatch.

I have seen cars with smaller turbo's go slower when they touched the heads alone. cam is in the same field. Even a cheapo flat tappet is miles ahead.

 

[jerrad]

Their site shows that the irons get 100# springs. I didn't tell them other wise so I assume I have 100#ers in there. I guess I'll check for convertor slip and than cam is next.

 

[jerrad]

Am I right that I have to be a WOT to check for slip?
Getting ready to head home and test it out.
Thanks

 

[KevinB]

Am I right that I have to be a WOT to check for slip?
Getting ready to head home and test it out.
Thanks

Yes. Those calculations on tci site are for the 1/4 mile. W/o being on the track, I'm not sure what you can check. Maybe start by using the tach on the scanmaster and see where the car shifts.

 

[jerrad]

Well, after hitting test and tune road, the car shifted at 4475 at 65mph with a 26" tire. The calculator shows 55% slippage but that is based on the quarter, anyone guess what it would really be?

 

[KevinB]

That 55% doesn't sound right. You are losing some by the car shifting that early imo.

 

[jerrad]

I should be shifting around 5500 correct? What can I do to make it shift later?

 

[BMF_Racing]

I should be shifting around 5500 correct? What can I do to make it shift later?

You will have to shift manually. To get an acurate slippage rate you will have to start in second and run it up to 5300 rpm (or so) and bump it into Drive. Run it on out and observe what your Mph is around 4900 to 5000 if the road allows you to do so. By starting in second and shifting into high under load will simulate the second half of the 1/4 mile pass. If you do this again and shift at 4500 rpm you will see a higher slippage rate at the top of 3rd with short shifting the 2-3 gear change.

My car will shift at 4400 if I leave it in drive. I shifted it at 5400 manually in each gear and picked up 3 mph in the 1/4 because of less slippage, even though I am shifting out of my powerband (my dyno hp #'s peaked at 4900), because it gives the converter a chance to couple in the next gear.

Hope that helps.

 

[jerrad]

Thanks BMF, there is a dyno about 20 minutes from my house so I might get a couple runs on it and see where my rpms are at 110.

I think Dusty said that on a dyno it will show more slip than actually is occuring.

 

[BMF_Racing]

Thanks BMF, there is a dyno about 20 minutes from my house so I might get a couple runs on it and see where my rpms are at 110.

I think Dusty said that on a dyno it will show more slip than actually is occuring.

Depending on the dyno, that can be true. Mustang dynos typically show more slippage due to the load that is applied with them on the roller wheel. Either way, you can try the two different shift points and see the difference in slippage.

 

[Rayk]

I have to take issue with the thought that your cam is a mismatch with your Champion heads. My combo is a bone stock long block with stock cam, TA49, Blues, Stock stretch, Alchy. With the stock heads my car would trap at 112-113 MPH at 22PSI. After adding Champion Irons with 100 lb springs, trap speed increased to 116-117 MPH. No other changes. None. My converter, by the way, is the modified stock diameter 2800 and I have the converter lock-up programmed into my TT chip at 70MPH. (just after the 2-3 shift).

I think if you up the boost to 22-23 PSI and start locking the converter in 3rd gear you should see 90+ MPH in the 1/8 and 113-114+ in the 1/4. And, you definitely need to start holding 2nd gear to 5500 or so. Good luck.

 

[KevinB]

I have to take issue with the thought that your cam is a mismatch with your Champion heads. My combo is a bone stock long block with stock cam, TA49, Blues, Stock stretch, Alchy. With the stock heads my car would trap at 112-113 MPH at 22PSI. After adding Champion Irons with 100 lb springs, trap speed increased to 116-117 MPH. No other changes. None. My converter, by the way, is the modified stock diameter 2800 and I have the converter lock-up programmed into my TT chip at 70MPH. (just after the 2-3 shift).

I think if you up the boost to 22-23 PSI and start locking the converter in 3rd gear you should see 90+ MPH in the 1/8 and 113-114+ in the 1/4. And, you definitely need to start holding 2nd gear to 5500 or so. Good luck.

Kinda off subject, but your traps are what I am looking for in a car I just put together. Stock cam, 44 turbo, ported heads w/100 lb springs, ported intake and all the other stuff in between. Have not got it on the track yet but it is a beast on the street at only 15 pounds.

 

[jerrad]

Thanks Ray.
I wish I lived closer to the track.

 

[jerrad]

Kinda off subject, but your traps are what I am looking for in a car I just put together. Stock cam, 44 turbo, ported heads w/100 lb springs, ported intake and all the other stuff in between. Have not got it on the track yet but it is a beast on the street at only 15 pounds.

Stay on subject


JK, thanks for all the help and advice guys.:smile:

 

[KevinB]

Stay on subject


JK, thanks for all the help and advice guys.:smile:

No Prob lol.

Brad (BMF Racing) is experiencing the same possible issues right now with the converter (although we do not know for sure that is yours.)

His car should have a new converter in it in a week or so. I'm thinking his car will pick up a lot if the new converter is right on the first try. It did 11.7 last weekend, I'm thinking the mph will pick up a lot. We'll see

 

[Razor]

I have to take issue with the thought that your cam is a mismatch with your Champion heads. My combo is a bone stock long block with stock cam, TA49, Blues, Stock stretch, Alchy. With the stock heads my car would trap at 112-113 MPH at 22PSI. After adding Champion Irons with 100 lb springs, trap speed increased to 116-117 MPH. No other changes. None. My converter, by the way, is the modified stock diameter 2800 and I have the converter lock-up programmed into my TT chip at 70MPH. (just after the 2-3 shift).

I think if you up the boost to 22-23 PSI and start locking the converter in 3rd gear you should see 90+ MPH in the 1/8 and 113-114+ in the 1/4. And, you definitely need to start holding 2nd gear to 5500 or so. Good luck.

I had a Reed 210/205 flat tappet and the car was stuck at 10.90-11.1 at 122. Went with the 212 roller and it dropped to 10.6 at 128 no other changes.

Stock cam loses steam at 4800-5000 RPM's. Any dyno pull will show that. So shifting it higher than 5200 doesnt make any more power.. sounds cool tho.

 

[Dusty Bradford]

No Prob lol.

Brad (BMF Racing) is experiencing the same possible issues right now with the converter (although we do not know for sure that is yours.)

His car should have a new converter in it in a week or so. I'm thinking his car will pick up a lot if the new converter is right on the first try. It did 11.7 last weekend, I'm thinking the mph will pick up a lot. We'll see

Let us know what you find with Brad's. Sounds more like a spring or cam issue if the rev's reach 5500 and stop climbing. That car needs something to take WOT lock-up with the oversized turbo and limited rpm range. It needs the rev's down but you can't spool the turbo if the converter matches the rpm range.

 

[BMF_Racing]

Let us know what you find with Brad's. Sounds more like a spring or cam issue if the rev's reach 5500 and stop climbing. That car needs something to take WOT lock-up with the oversized turbo and limited rpm range. It needs the rev's down but you can't spool the turbo if the converter matches the rpm range.

will do. :biggrin: yeah it spools like no other with the t-brake and DBB.

 

[Rayk]

I had a Reed 210/205 flat tappet and the car was stuck at 10.90-11.1 at 122. Went with the 212 roller and it dropped to 10.6 at 128 no other changes.

Stock cam loses steam at 4800-5000 RPM's. Any dyno pull will show that. So shifting it higher than 5200 doesnt make any more power.. sounds cool tho.

My comment didn't address the difference between a FT cam and a roller. I merely said that I disagreed with your statement that the stock cam was a mismatch with his Champion heads by comparing the improvement I got with my stock cam motor after adding the Champions.

As for a stock cam being washed up after 5000 RPM, I agree with you. However, there may still be a benefit to shifting at a higher RPM so that the next gear will start higher in the power range and also allow the converter to slip less. My car goes faster (ET wise) when I shift at 5500 vs shifting at 5000 even with my stock cam. Go figure.

 

[BMF_Racing]

My comment didn't address the difference between a FT cam and a roller. I merely said that I disagreed with your statement that the stock cam was a mismatch with his Champion heads by comparing the improvement I got with my stock cam motor after adding the Champions.

As for a stock cam being washed up after 5000 RPM, I agree with you. However, there may still be a benefit to shifting at a higher RPM so that the next gear will start higher in the power range and also allow the converter to slip less. My car goes faster (ET wise) when I shift at 5500 vs shifting at 5000 even with my stock cam. Go figure.

x2 :biggrin: