Just wondering?

[workingdan]

I was wondering if when I put a 70mm TB and a 4" MAF pipe if that could make my car slower? I went to the track last night and my car ran a second slower than it did last year. I changed the TB from stock and added a RJC 4" MAF pipe from a 3" that was on the car when I bought it. I also added a home made cold air kit. The only other thing that was differnt from last year, is I ran a 28" tall tire last year and this year I ran a 26". And last yeat I opened my exhust cut out and this year I ran it thru the mufflers.
Any I ideas? Thanks
This years run Last years run
60ft= 1.6859 1.7649
1/8 ET= 8.0920 7.4810
1/8 MPH= 83.47 93.96
1/4 ET= 12.7829 11.7060
1/4 MPH= 105.17 114.15

 

[notacarlo]

26" tires = lower trap speed and slightly better 60' than a 28". What was the outside temp?

You do not need a 70mm TB. Will it slow you down? I've heard it both ways.

 

[workingdan]

26" tires = lower trap speed and slightly better 60' than a 28". What was the outside temp?

You do not need a 70mm TB. Will it slow you down? I've heard it both ways.

Outside temp was cooler (about 80) than it was last year. Humidity was beeter this year too.

Ya I knew I didnt need one that big yet, but I didnt want to buy 2

 

[breiter]

Outside temp was cooler (about 80) than it was last year. Humidity was beeter this year too.

Ya I knew I didnt need one that big yet, but I didnt want to buy 2

I just changed to a 70mm TB and it did not really change anything other than looking cool. It actually my have slowed me down. I was running 28 inch slicks and it seemed to be slow out of the hole. I sold them and bought 26 inch slicks but have not run them yet. We run 1/8 mile so I think it will pick up a couple tenths with the right tune.

 

[bison]

I doubt the 70 mm TB hurt you. Dont see how it could. Is not helping though. The 4" inlet should help a tiny bit but not much. Homemade cold air induction? Ive seen those hurt before but not slow the car down a sec. .3 loss on a 115mph car. Losing 9mph is more than noticeable on the street and you should have known about the power loss before running it. Maybe your hose is collapsing under power?