89/383

hi guys first time here and I have to say this is a nice site. I just got done building my car and breaking in the cam last week, and was wondering if this thing has a good chance at an 11 sec pass. heres my combo 1989 camaro z28
motor:GM 4 bolt 350 .060 over
Eagle cast crank 3.75 stroke
eagle 4340 I beams
hyper flattops
cam .480 lift .230 dur @.050
pocket ported 461 heads 2.02in 1.6exh
performer intake
holley 650dp carb
im not to sure on compression speedpro told me 10.5:1
accel HEI with super coil and msd 6AL
holley blue pump with 10 gal cell and 1/2" line running all the way to the regulator
the tranny is a th350
B&M converter
B&M shift kit
moroso tranny cooler
the body also has subframe connectors, an 8pt cage, battery relocated to the trunk (if that makes a difference),and most of the interior gutted.the rear end is stock, and I would of course be running on some kind of slick. I have no suspension work done and would like to know what's a good drag setup for our 3rd gens. thanks for any comments or help.

1320_Guy

iTrader: (3)

It is possible, if the rearend holds togeather for 1 run.

xpndbl3

iTrader: (5)

13.0 at best 12.7

89/383

you really think so? got any suggestions to make it faster?

Trevor86TA

Heads/Cam and converter.

What are you running for headers and exhaust?

1BADRZ28

iTrader: (2)

add nitrous for an 11 sec pass. Your cam and heads are a great street set up. But not much for making 400-450 hp that you would need to break in the 11's

5678TA

you have a chance of getting mid to low 12's.. no faster than 12's i say..

your whole top end is weak for a 388.. performer intake, rather small cam, 650DP, not sure about the heads.. it should be performer RPM, cam in the .500" lift department, 750DP, and maybe a little more than pocket ported heads..

and about the compression ratio, dont guess.. i guessed with my motor and a got screwed.. i picked a cam for 10.5:1 MINIMUM and i was only running a true 10.1:1.. power was really lazy all over the rpm range.. no grunt down low, no pull up top.. still got me a 12.41 @110 though..

but my guess is def a mid 12..

IHI

iTrader: (1)

high 12's in normal air-and the only reason your not consistant low 13's is due to it being stroked, but the fact your stroked and running junk heads is the nail in the coffin more so than the peanut cam.

only fix-new heads and your budget will dictate how good of a head you can upgrade to, but ANYTHING aftermarket will be eons above where your at. The cam your running is the bracket master II I take it?? you should've gotten the one that is a step larger than your current one, but in reality, these grinds are old tech and much more effecient grinds are out there. When you get ready to change cams, go solid flat tappet at a minimum-you'll be very happy with the additional power. Not saying you current cam is bad, just a dated design. It will sound good, be great the first 1/8th mile and then fall off after that. I've been there with it.

if your at 10.5 static compression with the iron heads, there's a good chance you'll have to mix some race gas to prevent knock cuz your going to find yourself in the 36-38* total timing range so pre-ignition will be an issue trying to run 91 octane.

get a vic jr. with 1" 4 hole spacer, put that dual plane on ebay or sell locally. you have everything to gain and nothing to lose with this swap. Once you upgrade heads switch over to a 2" spacer and try the 4 hole and opn to see which your engine like best.

Your carb is waay too small. a 750HP would be ideal, but you might as well buy the 950HP now as it will still work great on your car and you'll be able to use it later when you upgrade heads, but that 650 needs to go bye bye, find a buddy with a daily driver or a 305 motor. 7 buddies all went from typical 700DP, 750DP and bought the 950HP-minimum gain with nothing else changed was .3-we all joked when we'd borrow out our 950's to guys wanting to see what it's do and would warn them, dont try it, cuz this run will cost you $650 to upgrade carbs

Suspension wise, your stock set-up will suffice just fine for what you'll et/mph, just invest in some bias ply slicks and you'll be good. Save the drag radials for teh guys trying to go fast fast with a bunch of suspension mods done already since that is what they need to work consistantly. And since you'll just be getting this car out, you HAVE to have consistancy out of the box to see if any changes you do are making a difference.

89/383

im running hooker super comps dumping to 3" true duel exhaust I have cutouts but I have always been told a good free flowing exhaust is better then running on open headers, I did'nt run anymore cam because I was worried about piston to valve clearence the piston being flat top and the heads are 62 cc chamberd, as far as heads I was thinking some dart iron eagle cause there in my price range. I have a NOS plate system and was going to run a 100 shot with race gas eventually thats why the fuel system looks to be overkill but im afraid to run it on hypers now with what everyones telling me.

IHI

iTrader: (1)

I run the same headers now and had heddman LT prior on my 355, both engines ran identical times corked and uncorked..did'nt even see any gain from the weight reduction even though they both just dump in front of rear diff. More and more guys are finally realizing muffler tech has come along ways and open headers dont give you any more power than a good free flowing exhaust-hence more cars running exhaust.

.515 is'nt that much more lift, even with shaved heads. It would've just been a matter of advancing the cam or fly cutting some notches into the piston-either way, using thicker head gaskets, not a big deal and if your block was not zero-decked you have a long ways to go before worrying about hitting slugs. I know you were being cautious, but in this case, it cost you power unfortunately.

the iron eagels are far better than where your at and would be a great upgrade. with your displacement serious looking into at least 200-220cc runners though, cuz once you get the right cam in there it will need to breath.

Personally I would not trust that single holley blue to feed the engine AND the nitrous. The blue was a good choice for the engine, now buy another blue, a red would even suffice and dedicate a pump for the nitrous only. Other wise your going to risk leaning out the motor. I ran the holley blue with HP springs and it cannot keep up to feed my 388, at WOT psi drops to 3. I had planned on using 1 pump to feed my motor and nitrous if/.when I got it, hence the A2000-waay overkill, but at WOT the thing was rock steady on fuel pressure. BIL runs same pump on his 383 and 500 fogger system jetted for 250hp and his needle stays rock solid...but we're talking day and night difference in pump capacity. The 4 holley blues I've had (yeah-they're junk) best one put out stock 1 gallon in 40 sseconds...my A2000 did the same feat in 7seconds. It's upto you, but all my racing buddies found through expensive trail and error it was easier to run a dedicated pump for juice soelnoids.

you dedicate a fuel pump, get your tune right, those hypers will take 125 shot all day long-but the tune must be good.

as for the rear suspension question-get the slicks and be done. Once you get that motor redone to make some power, then start upgrading components, but right now there is no need to waste money on something that is'nt going to make you any faster/more consistant

89/383

well if I want to run nitrous ill add another pump and a dedicated line for it per your advise that is if you guys think the hypers will take it. I have a little more money to spend so I will probably look into getting a set of dart iron eagles in the 220 intake runner size I know the carb is killing me I really only used it to fire the motoer up and break in the cam, if I get a new set of heads should I look into keeping the same size combustion chambers?

oya my exhaust dumps into super 40's goes over the rear axel so It is a full exhaust system

IHI

iTrader: (1)

The hypers will take it, it's not like your building a nitrous pass only motor-this will just be fore play now and then. We've got 3 cars in our grouop running cast slugs on motors built 5-7 years ago, average 10-15 bottles per season and no problem yet...but you have to have the tune right, this is the reasonnitrous is so hard on stuff especially if runnig lean-which it will do terribly if trying to feed your engine and nitrous off that little blue pump-just not enough fuel being pushed for that.

The new heads will typically offer 64 or 72 cc heads, these numbes are not exact and if you have then tested they will be +/- around 3-5 cc per chamber of what's they're advertised with. So given current set-up stick with the 64cc's to stay around the 10.5 static mark. This will allow you to improve performance with a bumpstick change since it will allow for more duration and once you factor in cylinder bleed off it should put you easily back into pump gas range. I'm suspecting a you'll be recommended a cam in the 240/250 duration and 108-110LSA.

As far as your exhaust you can try 2 things for ***** and giggles:
1. try removing the pipes that come out of the mufflers and go over axle and see how much if any that picks you up.

2. after that, uncork it and see what happens.

I think depending on your exhaust layout/design you should notice an improvement by remooving the pipes going over the axles so the mufflers are the final exit point, and if that improves I dont think you'll notice much by uncorking...but again just depends on how your current set-up is.

5678TA

i have run 10.7:1 static compression with camel backs on pumpgas with no problem.. i have the holley blue pump and it works pretty good for me.. i hold about 6.5 psi.. dont know how it looks at WOT though..

you will not have any piston to valve clearance problems with that cam.. i have over .1" more lift than you(.592") and i dont have a problem..

IHI, does a 950 really work that well?? i ask because i'm in the fight to get as far into the 11's as possible.. i'm running a 385 with a mighty demon 750 with annular boosters right now.. i run a manual as well so i do need lowend torque.. while running the speed limit in 5th, i'm at 1700rpm..

IHI

iTrader: (1)

You'll pick up in 2 area's:

1. your getting rid of that BG POS-sorry to be so brash, but my buddies that've tried it, switched and picked up et/mph, even when sticking with same size carb.

2. your stepping up in cfm-even though the 950HP's only wet flow's 830cfm. I've ran my 950 on my old 355 9.3:1 and picked up .4 switching frmo the 750 I previously ran. When it comes to going fast on the track, throw conventional wisdom out the window-the track like big carbs. As far as streetablity, none of us have ever had any complaints what so ever...this thing just flat out works and is about as close to a "tuned" carb as you'll ever get out of box.

It's a hefty investment, but it works-period. just wishing I woulda bought the 1000HP since I have to get a new carb in the near future for the new mill.

89/383

are you running flattops if so it looks like a biger cam is in my near future. a friend of mine has a holley 830 I can probobly get off him.

5678TA

wow.. i know what you mean about the BG being crap.. it took forever to tune and is still not putting up the numbers i was hoping for.. part was my fault.. didnt do my homework when getting the other parts together.. and a hefty investment the carb will be.. maybe i'll get it during the summer.. if the 950 only flows 830 as you said, i'll get it.. what about boosters?? downleg or annular? and do any of your friends run this carb with a manual? because this is a streetcar..

i am running Probe SRS flat tops with .025" piston to deck height and .015" steel shim gaskets..

89/383

could I increase the lift enough by going with a 1.6 or 1.7 rocker ratio?

1320_Guy

iTrader: (3)

Yes you can, just take the lift you have now and divide it by 1.5. Then multiply what you get by 1.6 or 1.7 to find out what your lift will be.

IHI

iTrader: (1)

Ours all have the downleg boosters, I've ran annular boosters on other carbs and honestly did not see any performance/driveability gain with either one..guess my engine was'nt finicky enough But all the cars in our "group" serve dual purpose, so yes, they are street cars and get driven even if it's only 3-6K a year they get driven on the road, and zero issues. Actually once you get the tune it's incredible how tame these things are on the street. 2 of the cars are sbc powered 4 speed cars running 10.50's and the other 10.80's.

Before I jumped to the 950HP I had the holley race 830DP, when I made the switch from that carb to the 950 I did'nt see any increase in track performance, but the car became day and night different as far as consistency goes, it got really easy to dial in. But since these carbs both basically flow the same it's no wonder my car did'nt pick up, just got more consistant.

FWIW on the cam/lifters. You can install the 1.6's and it would take you from .480/.480 with the 1.5 to .512/.512 BUT you will not see any difference to warrant the expense of the new rockers and new pushrods. This is just one of those mods you do when initally building cuz you have to buy the parts anyways, so why not, but it is not the majic pill that will increase the performance your after...you'll just be wasting your money. I've seen this happen on the track first hand with 3 cars-all sbc's. keep in mind even if you can find 20hp somewheres, more than likely you will never see it on a race track time slip.

89/383

after searching for alittle while im thinking of a doug herbert solid cam
how does this one look http://www.dougherbert.com/solidcaml...cPath=83_84_86

IHI

iTrader: (1)

That looks good, but call the copmpany directly and let them pick a grind for you.

FWIW, I would really push THESE GUYS above all other's. Talk to Bob and tell him exactly what you have, what the intentions are for the car, etc...basically answer his questions and you'll get a bump stick that flat our performs. I was sold after my first one and this is a very popular copany with all the racers in the know

1BADRZ28

iTrader: (2)

Speaking of carbs. I just came off the dyno yesterday and used three different carbs. First was a 750 dp with a proform center section(this was my carb) second was a 930hp and thirdly a 1050 dominator. The results where that my proform'd carb made the same power as the other two carbs within a 2 hp. This was a 12:1 roller 406 motor. For two horsepower I didn't feel the need to dump 700 on a hp carb. Based on your combination the 650 will work as those heads probably won't flow more than 220 at .480 lift so don't waste your money on a new carb. That motor will make great torque on the street.

89/383

well I orderd a vic jr intake, the doug herbert solid cam listed above. and got a holley 4781(850 DP) carb off a buddy of mine. I dont plan on doing the heads until I have enough money to get what I want, I dont want to skimp on them. do you think any of these mods will help any?

oya I also got a red pump and regulator and im going to run a whole other fuel line and pump because im thinking nitrious in the future.