E/T estimate?
Thread Starter
Racer
Joined: Dec 2002
Posts: 367
Likes: 0
E/T estimate?
a want to run at the track in a few weeks, but I need an estimate on my E/T
350 bored .030''
flat-topped hypereutectic pistons
72 cc aluminun 2.02/1.60 heads
Speedpro cam, my engine builder just gave me all the specs, so I don't know which ones you need......... Duration at .050 intke. - .298 exhst - .304
intake lift - .310
exhaust lift - .325
gross lift .465 intake
gross lift .488 exhaust
centre line 107 degrees intake
centre line 117 degrees exhaust
dual plane intake similar to lt-1, not original l-82 intake
q-jet carb
long tube headers, 2.5 inch duals, with flo-pro redline mufflers
i think it has a 3.55 rear end
gkull ran my car on dd2000
I ran some simulations on DD2000 and I had to make some assumptions:
If your engine builder keeps the piston to head quench distance down you could achieve 10.2 compression. For the head flow numbers I used the standard Edelbrock aluminum. Your duration numbers of 298/304 would be a seat-to-seat advertised duration. Which is a pretty hot.
Your cam might be on the upper end of your dual planes intakes ability to flow. You also didn’t tell me carb CFM. So I input 750 cfm. 650-750 Vacuum secondary is your best choice IMO for a 355 ci
Anyway depending on attention to assembly detail and balancing. Then also of course optimizing carburetion and ignition give a large variance of power.
But expect 340-375 hp @6000 rpm and @340 lbs of TQ @4500
Safety Car
Joined: Aug 2000
Posts: 3,909
Likes: 26
From: Clymer PA
Re: E/T estimate? (Glutamine83)
I would imagine you could see high 12s low 13s or so with your setup. You didn't mention if you are running a manual transmission or an automatic transmission....this also plays a big part of the et. If you are running an automatic, what stall? What type of tires?
Those numbers are going to be your duration at seat to seat. I would also agree with what George said....the intake is definitely a mis-match with your cam selection. It's not going to hurt anything, you just aren't going to get the maximum amount out of your setup. With the bigger valves (what intake runner size are the heads) and bigger cam that motor is begging for a Performer RPM Air-Gap or mild single plane to match. :cheers:
Duration at .050 intke. - .298 exhst - .304
Thread Starter
Racer
Joined: Dec 2002
Posts: 367
Likes: 0
Re: E/T estimate? (bence13_33)
i have the 3 speed auto tranny th350.........looking to get a shift kit
also I'm running street tires Goodyear GTII 255/60/15's all around
will an air gap fit under the hood of my car?
also I'm running street tires Goodyear GTII 255/60/15's all around
will an air gap fit under the hood of my car?
Safety Car
Joined: Jun 2001
Posts: 4,004
Likes: 2
From: Severna Park Md
Re: E/T estimate? (Glutamine83)
Are you ready to and is yur motor capable of handling 7000 rpm? With long duration like that, thats what it will take to get the best out of that cam. Yur gonna be doggin out of the hole unless you got at least 3000 rpm stall speed convertor. The lift is not rediculous on that cam but the duration is pretty high. So whats yur stall speed and gear ratio? Those two variables are important to a cam with that much duration.
Instructor
Joined: Jun 2003
Posts: 158
Likes: 0
From: St. Albert Alberta
Re: E/T estimate? (Glutamine83)
How to utilize a high stall?
Put one foot on the brake... Put one foot on the gas
Remove brake foot, clear smoke from car. :reddevil
Unless you have a different style of converter... ehhh, I'm at a loss for words on that more 'racey' type.
Put one foot on the brake... Put one foot on the gas
Remove brake foot, clear smoke from car. :reddevil
Unless you have a different style of converter... ehhh, I'm at a loss for words on that more 'racey' type.
Safety Car
Joined: Jun 2001
Posts: 4,004
Likes: 2
From: Severna Park Md
Re: E/T estimate? (Glutamine83)
I found this in a search. I read it thru and learned a tip or two. It basically covers the bases in general. Good link.
http://www.therangerstation.com/dragracing.htm
when I launch, i first stage, then hold the brake down hard and depress the gas pedal. Just to the point where the car really wants to move. On the third yellow I realease the brake and the car lunges forward. A split second later I floor the gas pedal. I found that with street tires, if I slam the throttle the exact same time I release the brake I get wheel spin which gives me slower ET. There is a sweet spot for every vehicle. Practice is what will get you the best out of yours.
http://www.therangerstation.com/dragracing.htm
when I launch, i first stage, then hold the brake down hard and depress the gas pedal. Just to the point where the car really wants to move. On the third yellow I realease the brake and the car lunges forward. A split second later I floor the gas pedal. I found that with street tires, if I slam the throttle the exact same time I release the brake I get wheel spin which gives me slower ET. There is a sweet spot for every vehicle. Practice is what will get you the best out of yours.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Race Director
Joined: Jan 2003
Posts: 15,176
Likes: 88
From: State of Confusion
Re: E/T estimate? (Glutamine83)
Glutamine83, I can't give you a 'guesstimate' ET on your project. However, here are the important specs on my '79 Z28. Weight w/ driver 3800+. 355", 10.3:1 CR, Dart II heads (outta the box), Victor Jr intake (have run aluminum Chevy dual-plane {327/365 HP?} w/ no difference in ET), 750 Holley dbl pump, functional factory hood-scoop, Comp Cams 292H (.501"/244* @ .050 ?), roller-rockers, 'on-sale' headers, THM400 w/ 2.75, 1.57, 1:1 ratios, 8"/4000 RPM ATI converter, 12-bolt spool with 4.11/4.56 gears, 28" x 10" Goodyear Eagle slicks on 15" x 8" Weldwheels. On SUNOCO94, shifting @ 5800 RPM (winding it up results in no better ETs) gives me consistent ETs of 12.80s @ 107 (best of 12.77 @ 109). This is 'deep-staged', which I do for better Reaction Times, but costs me approx .15 in ET. This past week, it ran 12.93 @ 105+ with 4.11s in 88*+ conditions. I hope this helps give you some idea of your car's potential. Glen..... :chevy
