Club Cobra - Need help with a blower question

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Need help with a blower question

My daughter is buying a '92 Mustang with a 5.0 engine. The car is in Kansas and it has a Paxton NOVI 1000 blower on it. The engine has 19# injectors in it. The owner says it has not shown any fuel starvation. My question is can it be driven to Texas without burning the engine up? I will be driving at highway speeds. I have never messed with superchargers before and don't know about injector sizing for one. Any help would be greatly appreciated.
Steve

Well I'm no expert on blowers, but I have read a little on the subject. 19# is pretty small. Ford steps up to 24# on the 32 valve 4.6 which was 280-310 hp depending on the model. I think they were pushing the 4.6 up to 375 hp with the 24# injectors and I am fairly certain that at 400 hp they definately go up to the next size injectors.

You can cheet a little by increasing he fuel pressure and get a little more out of a given injector. However the next issue is always fuel line sizes and fuel pump size. You cannot just stick in bigger injectors, push a bunch of air, and go with it. The whole fuel system needs to be abble to supply enough fuel at the correct pressure.

It all depends on how much pressure the blower is pushing and what other modifications have been made. If your pushing much more than 5 psi there better be an intercooler. The computer will need a chip to take some timing out at higher boost to prevent detonation.

With all that said, as long as you do not stick your foot into it, it will be just fine. As long as the manifold stays on the vacuum scale (no boost) the injectors will not have to deliver any more fuel than it would without the blower.

I ran 19lb injectors for years , with my 6# blower, and never had a problem....Find out what size pump he is running...should be at least 190 lph....(prefer 255)...Any less, you will have to baby a little..but it will run fine....19lb injectors are good up to 325 hp or so, without a problem.

Thanks for the info. I feel better about all those miles at highway speed.
The pump is a 255, which I figured was OK. 19# injectors sounded small to me.
Thanks,
Steve

One more thing...You should run 93 octane gas only.

I always removed the belt from my Paxton equipped 88 mustang when I would go on an extended trip. Engine temp. would decrease & fuel mileage would increase.

tboneheller,
Thanks for the idea. Does removing the belt mess with the fuel air ratio in the computer? Isn't the MAF calibrated to the extra airflow? Wouldn't that make it really lean?
Thanks,
Steve

Quote:

Originally Posted by Seagull81 (Post 837878)

tboneheller,
Thanks for the idea. Does removing the belt mess with the fuel air ratio in the computer? Isn't the MAF calibrated to the extra airflow? Wouldn't that make it really lean?
Thanks,
Steve

No, the MAF is before the supercharger. With the belt removed, mine ran like a stock Mustang.

tboneheller,
Cool, thanks.
Steve