Seen plenty of local no prep guys run 67/62's on 4.8's and 5.3's

Would this be a horrible combo for a 408? I'm honestly not sure where these things even top out. And not sure if I want to pull them off and go NA for a bit or keep them on and redo hot and cold side and go mirror 78/75's at some point

 

I guess the question is, what are you wanting it to do? The 67's will hit really quick on a 408. Will you make more power overall if you put twin 76's on, absolutely. Will you make really good power with twin 67's absolutely.
I mean I have a buddy who has twin 80's on a 6.0. He runs it around 30#. Is it fast, yes, but it's definitely not the setup I want.

 

If you pull them off to go NA for a bit, that is going to last for what, 2 test drives before they go back on? Why bother?

 

I appreciate the replies

Me and my group of friends are super slow, I just want to do hard tire autocross/grandchampion stuff.

My circle of friends with autocross I think I may be competitive just NA with a 408

I think I like the laggy feel but may try the 67/62's since it's on the car already.

This past LS Fest east a bunch of people punched into the 9's (1/4) a good bit. I'd really like to just creep up to a 110~120 mph 1/8 mile trap on street. I know I need to work on 60' times




These are my circle of friend's times. Kind of feel like I can be competitive with just a 408 NA. But I'll try and run these turbos and will see what happens

The time under for my car was at LS Fest with soft timing and low boost on a 4.8. 8.33 et 60' of 2.32

Best time was 7.45 (1/8) on a hard tire 5.3 on 8lbs at 100 mph

 

I don't know when 67/62's choke out on an engine like that is basically what I'm saying. I feel weird putting 800 whp turbos on the car when the engine may make 500 whp na

 

Brian Nutter, just posted on Facebook about something very similar to what you're asking.

 

Any idea what group?

 

Sorry I don't, you can probably just look him up and find it. If I run across it, I'll add a link

 

https://www.facebook.com/share/p/1DJa7fLwJp/

 

I have a buddy that has twin 67's on a 408 and he made around 950 wheel on 25 psi. Go on YouTube and look up no problem raceway fire on the bayou and you will see a silver caprice, thats the car. Keep in mind these were only vs racing turbos, he plans to go bigger but the car still made great power and its pretty quick. It traps 130+ in the 8th.