switching from 17's to 19's slow my car down?

Im thinking about putting 20's on the back and 19's in the front. Would it be better if i just put 19's all the way around or it wouldnt matter much? Also, will this slow my car down at all?

I was thinking of these..

http://store.summitracing.com/partd...400100 4294906456 4294793317 115&autoview=sku

i believe those wheels will not only slow your car down they may slow your checking account down too.im jealous.

Those wheels look awesome!

I have those Weld forge-star wheels in 20x9 front and 20x10.5 rear and absolutely love them, but yes the car does feel slower. This is just seat of the pants feel as I have not taken the car to the track since installing these wheels....

any pics coupe302?

Looks great! I'm also looking to get 19s

Here, use this to find out how much slower: http://www.1010tires.com/TireSizeCalculator.asp?action=submit

if the overall weight is more than stock, it will slow you down some.

It's all about the weight and of course a harsh ride too compared to the 17's.

Are these fitted to your 2005 though?

I have a set of Weld Forgestars in those sizes (20 x 9.5 and 20 x 10.5) which I ordered for my 2005 GT in November last year. After having them imported to the UK and paying loads of tax and shipping costs, I was furious to find that when finally got tires fitted, the wheels didn't even fit. The wheel lug nuts supplied shattered their crowns as the bolts were obviously too long and when I came to drive the car into the garage, i found the rear wheels had clamped on the rear calipers. Luckily the spokes had settled against the caliper. If they'd been either side, they'd have ripped the caliper off. The problem is that the curvature of the spokes clamps the brakes on.

I have spent an arduous 6 MONTHS waiting for Weld to sort this out and have still to receive the spacers they are supposed to be having custom made for me so I can fit the wheels. I sold the stock wheels so the car has been US for the past month or so while Weld try and get their act together.

If I hadn't paid shipping to the UK plus import tax and 17.5% VAT on top I'd have sent them straight back but I stand to be about $1000 out if I do that. If don't get the spacers soon, I'll be hurling them back to the US physically. It's a same as I had to hunt down these wheels for my Mustang and so far have had the most appalling service from Weld and wouldn't recommend them to anyone.

I anticipate they may have redesigned the wheel by now to resolve it. It's just a shame that people like me have been royally stuffed in the process.

yes

Just like when stangers buy aluminum driveshafts for their cars, any rotating mass causes driveline loss.. and your wheels are the largest source of this.. anytime you increase the diameter of your rim, you are placing more weight further out from the center and creating a need for increased cenfripedal force( more power to turn). the only way to look stylish without losing any speed would be to get light weight rims( i believe steeda ans saleen both carry these) .
But if looks over speed rule, then get them anyway, and just add a Cold air kit or some other power-adder.

Peace-
Matt