My combo: 86 Firebird 355 flat top pistons 10.5:1 comp. vortec heads with 3 angle valve job 1.5 stamped steel rockers edelbrock performer rpm intake 670 holley street avenger sfi approved balancer and flexplate hedman sporty headers crane extreme energy cam 282 adv duration 470 lift and degreed. 700r4 tranny with a hughes 2500 stall convert. 4:10 posi. I got hurt shortly after I got my combo installed and have not been able to drive the car little long take it to the track. I finished the install in early april and just got to log some miles on it in the past week. It does feel to be pretty strong. By the seat of my pants driving it feels to be a lot stronger than my 2000 NHRA Edition Formula that I used to have. Now with me returning to work after being off for 4 months I don't know if I'll have the time to take it to the track before they close for the season. So any help would be great.

Mid to low 13's with traction. You might be overgeared for that cam and head setup.
Hope you can find the time to get out there.
Good luck.

Thanks, I was wishing for high 12's like a 12.80 or 12.90. Guess there is only one way to find out. The sad thing is, I may have to wait until next spring.

Well, u need to figure out what cam u got.... the xe274 is 490" lift, and the xe268 is 480" lift, the xe284 on the other hand is 510" lift.. so anywhere from 106-110mph or so in the 1/4 and 85-90 in 1/8...et will depend on traction...

I'm sorry, I stated that I had a comp extreme energy cam when I actualy have a crane cam, with said lift and duration. These long shifts and 7 days a week are getting to me!

13.7-13.9ish. That cam may be hurting you with the gear set. It didn't say your exhaust setup?

id say mid 13's thats what i was running but ive got a little more motor and had no tranny. 2-4 band was fried lol

I'm going to have my exhaust reworked a little later on. I'm going to have it come back off each header with a cut out on each side then cross over behind the trans into a bullet then over the axle with a y and daul tips. Maybe. I'm not sure? I have been trying to look at the dual pics on the sticky tread in exhaust, but I can't get it to open up.
What gears do you guys suggest? I ran it the other day at a place we used to street race at. I know I should not have done this, but its a long stretch and I could see if anything was coming or not. We had measured it off along time ago so I know it was a 1/4 mile. Nothing was coming and no other car were around. Remember I live way out in the country. It pulled hard all the way through the 1/4, but that seemed about like that was all it had. It was already wound pretty thight. I just wish I had a G-tech with me that day.

In my old 84Z I had the gm 350HO

9.1:1 with stock vortecs
212/222 .435/.450 109lsa, cam that comes in it
Edelbrock performer air gap
Edelbrock 600 carb
Hooker 1 5/8 headers w/ 3" borla
2200 Stall and 3.73 gears
3300lb race weight

It went 13.6 @ 101 mph on bfg drag radials


With more compression and a bigger cam I don't see why you wouldn't be in the low 13's.
As stated, I agree that your gear will hurt you at the big end though.

Low 13s is my bet, let us know.

i'm running 12.90s at 111 with your setup except more camshaft, 770 street avenger, air gap, and a 3200 stall. this is on street tires with a 2.1 60ft. so with tires, 12s shouldnt be a problem for you. you need to change the intake, get more camshaft, and a bigger carb.

Yesterday I was driving along when a guy in a early to mid 90's vette starts riding my bumper. We were coming up on a section of road where it splits into two lanes going up a hill. I slow down to let the truck in front of me get some distance just in case he wanted to play. I looked in my mirror and he had fell way back. So I thought he didn't want to play. Then he does a ***** fly by. I notice him when he is already going around. So I kick it and by then he is at least a car in front of me. My car down shifts and I start to real him in. As I close in I can hear that it at least has an after market exhaust on it. Then I start to pass him. I pull up along his passenger side and look over at him and he's like I stay in it untill I get the front of my car pass his. His left front wheel was at my drivers door to rear quarter. Then I had to let off because we were coming up on the truck that was in front of us. Plus I was about to run out of gear. Remember I'm running 4:10s. I think that I may switch to 3:55's or something close to it. What gears do you guys think I should run with my set up.

i went to 4.11 when i put my 9inch in. for the street id like to have my 3.73's back. but im right where i want to be crossing the traps with the current set up. so its all in what you want. quarter mile or top end. rember also with a cam and a lockup stall or a clutch it could surge quite a bit during normal driving

My mods are in my sig, so you might get those high 12's.