My hybrid lost to a Mustang!

[zeeboost]

Well, it was a Supercharged Bullit dynoed at 458rwhp, but still, it makes me feel like crap. My engine must not be tuned too well...setup is: 350 bored . 030" with 10.5:1 flat tops, 280H cam, Holley Systemax aluminum heads, victor jr intake, Holley street avenger 670, MSD ignition, t56 tranny, 3.9:1 diffy, and hooker headers w/flowmaster exhuast. We were neck and neck through 2nd gear, but when I went into third he started pulling on me. All in all I ended up losing by about three car lengths. Good thing I didn't race his other car ('95 Cobra with headwork, supercharger, and 150 shot of nitrous )

 

It feels like the zx doesn't want to pull at top end. I'll get to about 130mph and it slowly climbs after that - I'm pretty sure the gearing wouldn't limit me at that. I don't know -- maybe I just expect too much of her, but it sure does make you feel slow when you've got the pedal mashed and all you can see is the taillights of a heavy rustang pull away from you.

 

I apologize to you for not properly representing the Hybrid Z community. Hopefully I can redeem myself soon

[80LS1T]

Dont feel too bad! He's got a super charger pushing 450+rwhp! Plus with that supercharger his probably got gobs of torque! Of course his car does weight like 3500lbs!

 

Whats your engine supposed to have as far as HP/TQ? Is your engine dyno tuned? Oh and how did you manage to get hooker headers in there?

 

Guy

[Forrest]

I have no idea what your transmission gearing is, but if you have the HP and you need more top end, sounds like the best thing to do is put in a slightly taller rear end, like 3.545.

[zeeboost]

Whoops! Sorry for the typo Guy (Hey come on, I posted this at 1:30 a.m. ) The headers are Headman block huggers; the collecter on the driver side was relocated down around the steering shaft. My setup is supposed to have around 430hp at the crank, but I doubt I'm pushing that much. I need to go get it dynoed, but something always breaks on it before I can take it out

 

I have considered buying a 3.54 diffy, but I would be seeing around 1600-1700 rpms on the highway, and with my cam and carb that wouldn't be too favorable. I have three things I'm still looking in to:

 

1) Running rich (friends have seen black smoke dump out when I'm gunning it, so I'd say that's a pretty good sign),

 

2) The carb will bog down pretty bad during takeoff (I'll try a bigger accelerator pump), and

 

3) It backfires pretty bad out of the exhaust when I let off at high rpm - not just a little burble, I mean LOUD like a shotgun backfiring. I've heard this could also be the symptoms of a rich condition, but I'm not sure. I'm contemplating just throwing on my Edelbrock 600 to see how the condition improves.

 

Perhaps after I fix these problems, I'll be able to hang up with him next time. Hopefully this time the Sheriff won't catch us

[fl327]

Id leave your combo alone, 3.9 is nice with a 6 speed.

Id concentrate on tuning, with what you have it sounds like you really need to tune it. Dyno it and see what it does, sounds like you have enough stank to run 11s.

[Z-Gad]

It sounds like the running rich problem could be the cause of all the symptoms you mentioned...

[Kevin Shasteen]

I think you have a good combo also and would not change it either. The problem w/our Z's with V8's are the intake system (need cool air) and the exhaust (need to get rid of the restrictions) and underhood temps.

 

Concentrate on getting rid of the improper exhaust restrictions and you will probably uncork your engine's inability to breath at higher rpm's.

 

Uncorking the exhaust restrictionis brought about by the Z's limited underbelly for a true free breathing exhaust-is the biggest major hurdle (IMHO) we have to overcome.

 

Do these things: and your car will come alive at higher rpms

1) Redirect Cooler air in to the radiator coupled w/a K&N type intake filter

2) Use the liquid expand type foam in a can to fill in void's and openings surroundig the radiator core support: this forces ALL THE AIR through the radiator

3) Make sure you also have a system that vents the underhood temp's out

4) Fabricate a true free breathing dual exhuast w/out the excessively crimped bends

 

If your engine is running rich-my question would be....HOW RICH? If you dont know then that should be your first area of concern-then the other items.

 

I agree w/the other guys-tune it first then begin messing with other stuff.

 

Kevin,

(Yea,Still an Inliner)

[zeeboost]

Thanks for the replies, fellas. Kevin: If it's the engine temp you're concerned about, I'm running from 160-170 on the highway. I was overheating, but a Griffin radiator and dual pushing electric fans fixed that problem. As for my exhuast, it is a true dual with 2.25" pipe all the way out. The only thing is that the car has been lowered approx. 3", so there's really no way for me to avoid the "excessive" bends because they were necessary to fit.

 

Now, my air intake does need improvement -- it's a K&N air filter, but I draw in all of the hot air in the engine bay. I want to get ArizonaZcar's twin turbo hood, and have a T-fitting over the carb and run dual cone filters right next to the openings to help solve that problem, but if it doesn't work out, I'll probably just end up cutting my hood to make way for a scoop.

 

I have the stock hood vents (280zx) to help vent out the engine bay, but I'm also thinking about making a couple of vents on the front fender right behind the front wheel to help with the venting.

 

I think I may just throw on the Edelbrock this weekend to see how she runs.

 

Thanks again