ok so i went out with my new engine i built over the winter it ran 13.4 at 102 in the quarter on my 1972 cutlass its a 350 with flat tops about 9.75 to 1 comp with a comp cams 280h reworked heads with 2.072 valves in. and 1.73 exh edelbrock rpm intake and 600 cfm carb headers 3.73 gear and 2200 stall is does this sound good i was impressed with my last set up 13.7 but i wanna get atleast a 13.0 out of this im running an x pipe with mufflers thinking of running open x pipe and actually using an air pan with my ram air hood pin on and adding a k&n sub stack and jetting up the edelbrock i know it might seem small but this carb feeds it really well all the way to 6k rpm any suggestions tips will be helpful

 

Sounds good to me, a bigger carb would help.

 

I agree with jag, how do you know it's feeding it well until you try something else.

Jmo.

 

i tried an edelbrock 750 way too much i had a proform 650 double pumper on there was good but drivability was horrible the 600 worked great i think with smome jetting i might drop a tenth or two

 

What was you rpm at the end of your run? You might consider more gear.

 

I have my doubts that a 650 Proform would have that bad of drivability. did you tune those carbs as well?

 

It would tell us a lot if you posted some of you're time slips with all the numbers 60ft 1/8 mph etc.looks like you are close to you're goal just need to tweak set up.

 

Getting it dyno tuned is prolly the best way to dial in your ride IMO. You can also put a shorter tire on and gain a little gear that way. guess theres a few variables with that. So rpms at the end of the track would be helpfull.

 

Same experience...everyone says "use a bigger carb"...never worked for me. Matter of fact, some of the same ones in this thread telling you to do it as well. Glad you were smart enough to stick with what your own experience and testing told you worked best on your vehicle. Also, I saw testing done with the stub stack, and it literally did NOTHING on the dyno. Don't waste that much cash on a useless item.

 

This is where trying, tuning (and more tuning, and more tuning) and having an open mind yields results. This will give more usable experience than the burger joint boys at the drive thru.
I have heard the stub stack for the Edelbrock has had issues (I never tried the carter style unit), our Holley stub stack was ALWAYS worth 1 tenth (which equated to 10 hp at our level). We tried a number of times removing it, it always slowed down.

Every combo IS different, borrow parts before you buy them, try them out first. Don't ever think that because it did not work this time around it never will in the future. Go back later and try it again, some of your other changes may require that old unit that did not work so well before.

Our car ran quicker and faster with a 750.

Jim

 

i trap at 5800 rpm and shift at 6k rpm the proform was just way too big i tuned it tried every combo just too big time was 13.4 at 102 60ft. was 2.068 i thing im close im just gonna do bolt ons with my last set up an x pipe added 2 tenths im happy with a 13.4 but i know i can get a 13.0 of course i need a higher stall and bigger gear but im trying to avoid that i drive the car on the street alot to work and i know that simple bolt ons help alot i think im gonna fatten up the secondaries add a ram air pan to my ram air hood and run an open x pipe instead of running through the mufflers i know people say you dont know if its getting enough fuel but it has no flat spots through the rpm i might need more fuel but again jetting might help get atenth or two

 

Higher stall, more gear, bigger carb= more fuel, and that aint cheap stuff anymore. It's down to $3.25 a gallon for the pee juice, here.

Cold fuel lines (I've seen guys use wood clothespins), ram air, plastic carb spacers, alum. heat shields, to begin with.
Also, what kind of pulleys are on the car? Small crank pulley/ large water pump pulley can gain an easy tenth over the A/C pulley's. The fan can cost double that.

Just an idea.

Jim

 

coppercutlass, you only want to make one change at a time. then fine tune that change.
then go to the next and so on . One thing I see right away is (IMO) you are shifting way
to high RPM. Try leaving it in drive once or twice, then start shifting higher a few hundred RPM at a time. I would bet your gonna find 6000 is to much. probably around 4800- 5200.
The 1-2 shift rpm maybe different than 2-3 shift.

oh and are you running slicks? I think you could get that 60 ft down to 1.8 ==1.9
are your 60 ftrs close or are they all over the place?

 

His ran slower. He was smart to go back to the 600, b/c that was what "Tuning and re-tuning" gave him the best times. As he said, " i tuned it and tried every combo." Each person tests their own engine and tunes it. Once they get the sweet spot, they should stick to it. I love watching the pros on the speed channel who hold the world records etc. who always repeat this mantra. They talk about dialing in their car, a car they know best.
Also, Google "Stub stack waste of money" and check it out. You guys must be one of the lucky ones. For the record, the stub stack I saw dyno tested was a K&N. The official conclusion was that for cars with LOTS of HP it may be benneficial to a very small degree, but for a car like the one in question...worthless...thus my suggestion for Coppercutlass to save himself the $$.
I like Red 71's sugestion for modification. Common sense dictates that with every mod, a person should attempt to re-tune. Doesn't mean it is needed, but should be attempted.

My opinion

 

i do change the shift point or did the last time i went out i ran my fastest shifting at 6k and ran slower shiftin at a lower point i run underdrive pulleys manual steering and elec. water pump drive at the track i usually do one thing at a time i do run drag radials m/t 275 50 15 so that truns my gear to roughly a 3.90 next time im at the track im gonna try a bit of everything and see how it reacts im happy with 13.4 but i know it can do 13.0 i just gotta sqeeze it out my last motor started as a 13.9 motor with an x pipe and a shift light it went 13.7., In drive my trans shifts too early i tried it last year didnt work too well this might sound dumb but i like to do my mods before track time not while im at the track too much hassle so i usually do a few mods and see how it reacts i have only hit the track once this year plan on hitting it again soon end of july see how much more i can get out of it i also have a crappy throttle bracket it eats up a tenth if not bent properly lol

 

Well then you need to send him a throttle cable bracket cause he will need to do all of his testing and tuning over again due to inconsistent and non-valid results.

 

It only ran a tenth slower but everything was close my issues with the bigger carbs was part throttle not wot and the throttle bracket only moves a bit everything was still close 60 ft etc.

 

Coppercutlass. Get used to it. The "bigger and better" crowd never admits defeat, no matter what you tell them about YOUR car. They'll say "Get a bigger cam." So you get one and your cars runs like crap. They won't admit they're wrong about YOUR car but say, "You didn't degree the cam right," even though you degreed it perfectly. They say, "Get a bigger carb." You get a bigger carb and it doesn't help. They refuse defeat and tell you that "You failed to tune it properly." They tell you how stupid you are and how incompetent you are doing things. The thing they never tell you is:, hmmm..guess my suggestion was wrong. This is the internet, everyone knows more about YOUR car than you do.

 

Thanks 71 cutlass I know what you mean I usally go by what I feel is good or how the engine runs bigger isn't always better people don't know there is several versions of the edelbrock 600 and most won't know that electric choke edelbrocks are all tuned for ecenomy as any manual choke is performancer even my local goto olds guy said that car is running great with that 600 but if I put a 750 it might key word might pick up but I would have to de tune the 750 since its too big just to make it right a bone stock out the box 750 did not work for me a tuned 650 did nothing the 600 out the box worked the best all around

 

Interesting.
You can probably cut and bend a small tab to make what you have, perfectly stable.
I would get a new one, most Carter style carbs have dual mounting patterns so you can use a $3 q-jet bracket from a wrecking yard OR something more expensive on-line. Do it right.
You want consistent results for A-B-A testing.

You have obviously done quite a bit to the car, and those ET's are nothing to sneeze at. Don't let this one issue cause you more grief.
There is a lot of good info on here, look beyond the attitudes, and ego's people throw on the board. Use whatever suggestions you can to make your car go 12's. The ONLY competition should be is when you get back to the track.
This IS the internet, It's even easier to criticize other peoples suggestions.
Let's hear some positive ideas on how coppercutlass can get those 4 tenths.

 

There is always good info here I take everyones input for what it is everyone has had diffrent experiences diffrent set ups etc. Also keep in mind this is a street car driven a lot not a race car that strictly see's the track I could throw a 433 gear and a 3800 stall and a bigger carb and probably run 12's but I need that fine balance where it can run fast and have good street manners

 

I am a huge fan of short shifting the 1-2, especially in a heavy car.

Stage shallow, less consistent, but usually better ET.

Add a little air to your front tires.

Go to the track on a cold evening!! LOL


I have personally had better luck with larger carbs on my 350s, with extensive tuning and testing. If the pump shot is off on the larger carb, it might end up being slower, too many variables. Also, what is your fuel supply situation? A stock pump/lines may be costing you a bit.

 

That's the way to look at it. I agree with Warhead that your times are nothing to be ashamed of, problem is, as you pointed out, in order to go a second or two faster you will have to make modifications that take away street manners. I'm in the same boat. My 350 is modified and could be modified to go even faster, but b/c it's my everyday driver, I just have to be content to leave things where they are. Because you want your car to be streetable you may have to be content to leave things as they are as well. Of course always be looking for those improvements which can help your times but also keep your car streetable as well.

P.S. Capt Jim is right, forget the Summer time trials, hit the track in November!!

 

I have more than enough fuel supply 110 gph fuel pump fed by half inch line the last time at the track weather was 75 degrees . Don't get me wrong folks I'm happy with 13.4 but as any gearhead knows we can't leave it alone we gotta make it a little better also my car is light no interior so to speak I got racing buckets and a roll bar and my front fenders and hood are lightweight fiberglass I'm sure my car is under 3500 lbs roughly it also has a fuel cell also my suspension is near stock all I have for added traction is boxed control arms and stiffer rear springs hope that also helps

 

Or, if you want the best of both words, get a small N2O kit. I ran 12.77 shifting at 4800. That in a 3800 lb car with 3.42 gears.

That said, you could use more converter or maybe less cam. What cam is in it and where installed?

 

Cam is installed straight up 490 lift 230 duration @ .050 lift. Int and exh

 

Cam should peak about 5750 or so shift around 300 over peak hp.I would try shifting 1 to 2 at 5800 then 2 to 3 6000.

play with spacers,then jetting once one is added.

Also sometimes with tight converters vac sec carbs will 60 ft better.

Make sure getting full throttle sounds dumb but have found this many times.

Timing curve could possible help 60 ft.

And you're motor only needs probably
550 cfm but you size a carb by restriction not cfm OK technically both.How much wide open throttle vac if more than 1inch you are restricting the motor.

is there any tire spin at all?

You would need a ton more power I would think to get there with just MPH.

Have to work on short time 60ft you're leaving a ton there.

Car hole shots like a high 14 sec car.

Torque peak would be about 4400rpm with that converter you might be as good as you're going to get in the short time 60 ft.

Just throwing some stuff out there.

 

i know my converter is killing my 60 ft it has no tires spin hooks good im gonna try a spacer just ordered some stuff from summit to mess around with at the track a spacer, a carb calibration kit and header collector rings so i can unbolt my mufflers at the track i hate cut outs the rust fast and look ugly and i run no tailpipes so its much easier my best 60 ft was last year with the same gear and converter but my last motor built alot more tq. it had a towing cam it was a 1.90 i will let you guys know if i go any faster thanks for all the replies it always helps to have extra info on hand

 

Might try degreeing cam for reference then advance it.Do a hot cranking test with carb wide open secondary's also post what you have.

 

Comp cams come ground with 4 degrees and all the old guys I hang out with that have 10 second 9 second cars told me install it straight up for street strip this isn't a all out race engine also its a 72 350 block with 6 head with 2.07 in and 1.71 ex valves running cast flat tops with 9.75 to 1 compression with a comp cams 490 lift 230 duration at .050 lift cam number 280h with roller tip rockers roller chain e brock rpm intake edelbrock 600 carb proform hei distributo underdrive crank pulley full length headers toro oil pan backed by a th400 with a 2200 stall I think that's it I know 13.0 is achiveable the mph is there I need better 60 ft. Times

 

Did you degree it? If not then you really don't know if it's straight up or not.

 

the engine runs fine no issues at all also comp cams specifies that degreeing the cam isnt necessary they grind their cams with 4 degrees advance in em so installing it straight up gives you that initial 4 degrees i installed as specified by comp cams i follow their instructions so it performs as they intended it to i trust the guys who designed it 13.4 from my 350 is good im just looking to add little things here and there to make it faster last year i added an x pipe to my old 350 combo it went from 13.99 to a 13.86 i added fiberglass fenders and hodd wet 13.71 my new combo went 13.41 with some more tunning i know i can get it there im not looking to redo the engine just make it a little better im more than happy to be running what i am like i said the mph is there for a 13.0 i just need to lower my 60 ft. so what i would need is a higher stall to start and maybe a 4.11 gear the engine perfroms flawlessly and pulls hard like every tuning guide says the mph does not lie and the mph is that of a 13.0 car the power is there where its coming in gear wise converter are my issues but if i do mods that bring up the hp and tq i wont need a gear and converter thats what im trying to achive

 

What carb spacer did you order? My engine gained over 20 hp/20 ft/lbs torque on the dyno with a 2 inch super sucker spacer. Unfortunately that wont fit under my hood. I need to spend time and see if I could sneak a 1 inch spacer under there maybe... I dunno.

 

Coppercutlass, have you ever heard of a period? They're great, they allow you to catch your breath and really better understand what someone is saying, try one sometime.
If you didn't degree your cam then you don't know where it really is, I don't care what Comp told you.

 

No one ever had an issue with periods on my post. Aside from that degreeing the cam at this point is pointless. The engine performs as it should the mph is right so its safe to say the cam is doing its job. there is no need to be angry if i don't take your advice but I also have my local olds racers who have raced for 30 plus years they said there is no need to degree the cam for your set up . I was looking for more constructive comments not get bashed by people who are hard headed. You bash my grammar and go out of you're way to do it shows the kind of person you are I'm not gonna take advice from a person who lacks respect to others

 

Can't help them all.

 

You are correct.

 

I like your combo and your build! I remember picking up 3 tenths by going to a shorter tire. An idea if you have a friend with some short slicks that they will loan you. I would stay with the small carb as your not turning that much RPM. Also, you can start adjusting your suspension. Good luck

 

ok guys it has been a while but i spent all weekend at the b.o.p wars in byron ill. and i lowered my e.t. not by much but i also didnt do much . i got it down to a 13.36 @ 103 mph. I uncorked the exhaust it made no diffrence , i installed air bags to add preload they didnt realy do much , i added a .5 in. spaced and intalled diffrent metering rods it got me an extra mph , what i found out really affects the car is the preload if i bring it too far into the converter it 60ft's like a dog if i preload it just enought to get the slack out it will 60 ft better ., I also found out it runs better if i shift at 6k rpm .,The 60 ft is what makes or brakes me i need a converter and im getting one from a fellow racer and friend once i drop the 60ft under the 2.0 it currently does i think i can get it to dip into the 12's