Old worn out blower vs brand new stripped Littlefield

[gregm784]

I've updated my blower. My Mooneyham had been maintained but wasn't ever restripped. It was very loose. At 25 over it would make 16-17#s max.

My new Littlefield is nice & tight (brand new). On my old combo, about 10% over was 14#s. I'm thinking starting this blower at 1:1 or even a few under to get the feel of it.

Is there a general consensus on how much a new blower pics up?

Mathmatically, 1:1 should be 14psi or so (387" sbc)

[George]

The Hampton 6:71 made 13-14 at 1/1. It made 21 at 16% over. Those numbers were with blower jell spray and everything warmed up . Chevy 377 all iron engine.

[dreracecar]

What I found is an "EVIL TRAP" , since we/you don't have 14 blowers or a spin fixture(except for the car itself) and fresh blower needs to break in and stabilize for consistency, because in index racing -Consistency is KING.  A fresh blower will come up to boost sooner so your front half times will quicken even though your boost numbers will be the same. As runs go by and the blower settles down, your early times  will slow but the boost numbers will be the same again.  The trap becomes when you have to send the blower back in to freshen it up all the time to maintain those numbers or buy the tools needed to re-strip it yourself, The other option is to purchase 3 matched blowers (we all know that's never going to happen LOL) and rotate car-spare-and one getting serviced.  Even tho it was Daves blower, I hated when he wanted to send it in, all my tune numbers were based on our weak-suck blower, back from the shop and those numbers didn't jive. Just my 2.5 cents-your results may vari and in case of severe armpit sweating, consult your doctor

[gregm784]

Thanks guys. The plan for Saturday is to run it 1:1, and tune for 15# of air. First pass will be in to high gear, and click it off to check the tune up.

Yup Bruce, i'm not going to keep super tight strips in this thing just for that reason.

[Paul New]

I would hold it out to 1000’

[gregm784]

I would hold it out to 1000’

It would be a better heat reading huh.

I'll pay attention to make sure it doesn't lay over until then.

[Paul New]

Yes at least 800’

[gregm784]

Headed out Saturday.

First pull went about 10 inches and lit the tires.  Bar to high, and dead hooked on a tight track.

Second pull went to 1000 feet. 7.79/131.  but 4.806/145.5 at the split.  Works out to a 7.48'ish

Third pull was clean, but i slowed it down to much, 7.89/169 (dead rich after another pulley swap to slow it down)

Jet area is now 0.017016. Had an 80 main (no HS). 6.67gpm pump. plugs are dead cold, car ran GREAT. New blower ended up 10 under, making 13.5-14#s.

Plugs in picture have 3 hits on them. Oil is clean, and motor is happy. Looking forward to ANRA (Famoso) November 8-10.