Help me reach the 11's

[Alf]

Just to let everyone know this is not a Z, but it is all Chevrolet. My goal with this car is to stay naturaly aspirated, look period correct in the mod department, and be streetable while running low 12's and maybe high 11's. I've come to all you knowledgable people for some advice on what it takes to get there, and any suggestions you have because i'm running out of ideas.

 

Okay here are the specs and current performance data: 69 Camaro, stock suspension, full weight, all steel, full interior, etc. etc. poly bushings all around and 90/10 shocks up front, lengthened traction bars. 12 bolt posi with 3.73 gears, all stock stuff. M/T 26 x 8.5 x 15 drag slicks mounted on 80's Camaro steelies. Muncie M20 wide ratio four speed, blowproof bellhousing, stock flywheel, 11" Hays street strip clutch, stock driveshaft.

 

Now for the good part, the engine.

 

bottom end/oiling- 1974 two bolt 014 casting, .030 over. cast crank 3.48" stroke, stock rods, cast speed pro flat top pistons with speed pro rings. stock oil pump, 69 Z/28 windage tray, 7qt Moroso kickout sump pan. 8" balancer.

 

valvetrain- Comp Cams Extreme Energy hydraulic flat tappet: duration at .050 intake-230 exhaust-236, lift-.490, LSA-110. matching comp valve springs and lifters(K kit). crane aluminum roller rockers. hardened pushrods.

 

heads- 67 GM 462 castings. angle milled, screw in studs and valve guides, slight port work, 2.02/1.60 stainless valves, 3 angle valve job. (these heads are off of a friend of my fathers 67 Camaro. The car ran low 11's with these heads in the 70's at Maple Grove dragway on a 327 with a monster solid roller cam. I found timeslips in the glove box, fastest was 11.29 at 120+)

 

intake system- edlebrock performer RPM, mild clean up and port matching. K&N 14x4" air filter in plain case.

 

exhaust system- Dynomax 1 7/8 ceramic coated long tube headers. no exhaust for the street yet.

 

ignition system- GM points dustributor with Ignitor electronic conversion and MSD cap-a-dapt ford style cap, no vacuum advance. MSD super conductor wires with moroso routing kit. Accell shorty plugs(the big style). MSD 6al CD box.

 

fuel system- stock Camaro fuel tank, sump, and line(3/8). carter performance fuel pump cheapie replaceable fuel filter. Holley 4779 750cfm double pumper.

 

performance data- 60'- 1.78

1/8- 8.17 @ 86

1/4- 12.82 @ 108.22 mph

All of these times were abserved on a 95 degree day in August at Cecil County dragway in Maryland.

 

calculated power- car weight- 3450(this is a conservative guestamate, car-3300, me-150)

3450lbs and 108.2 mph entered into a horsepower calculator rates my car at 341whp, and a estimated 12.59 with that mph. I was told that the hp calculators give average power figures, is this true? If so my peak is much high which isn't good for improvement.

 

Some of my ideas- try using an adjustable vacuum advance canister, optimize timing, optimize spark plug gap and heat range. I'm gonna try to get an A/F meter to get the fuel ratios good. I plan on doing a few carb mods like milling down throttle shafts and what not. I might swap for a screen type windage tray. I am going to build a dual tube style cool air inlet system. Thats about all i can think of right now. I would like to get as much out of it with basically what i have, as in heads, cam, and rotating assembly, but am willing to upgrade in the future. Any suggestions you guys have would be greatly apreciated.

 

Thanks in advance and sorry for the long post.

[grumpyvette]

the main restriction is the hydrolic lifter cam the durration and type of cam is not nearly correct, for a serious motor,your compression ratio should be slightly over 10:1 depending on the head gasket your useing and deck height, so swap to on of these cams, (below) and the thinnest head gasket you can get that maintains a .040-.044 quench distance (yes check ALL your clearances)

 

http://www.crower.com/misc/cam_spec/cam_finder.php?part_num=00322&x=34&y=8

 

http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=114681&lvl=2&prt=5

 

ID also do the following mods

Id install a tapered collector extension that slowly reduced & extended the collector exit dia. and added a minimum of 12 inches to the current collector length

 

http://www.holley.com/11752HKR.asp

 

 

ID swap to caltrac bars

 

http://www.hotrodsandhemis.com/Traction.html

 

and install a 4.11 rear gear ratio

 

the CALTRAC BARS and the cam SWAP are basically mandatory, the rear gear ratio and header collectors help but are less important

btw this may help

 

http://www.ramairbox.com/kits.html

 

and this

http://www.professional-products.com/manifoldsProductSBchevy.php (#52031)

 

those mods will get you much closer to the very low 12 second range, adding this also will get you into the 11s

 

http://store.summitracing.com/partdetail.asp?autofilter=1&part=NOS%2D02001NOS&N=400047+115&autoview=sku

[Guest Gr8White]

You are a pretty long way from the 11's...I don't think any basic tweaks are going to get you there either. One word...Nitrous! I would say it's going to take around 100 more RWHP to get you there. your 60' is a bit high, but probably isn't worth more than .10-.15 seconds in the 1/4 with a dead hook....On average, I'd say it takes around 112 mph to hit the high 11's, do your horsepower calculator based on 112 mph traps and you'll be close...

[powershift]

the main restriction is the hydrolic lifter cam the durration and type of cam is not nearly correct' date=' for a serious motor,your compression ratio should be slightly over 10:1 depending on the head gasket your useing and deck height, so swap to on of these cams, (below) and the thinnest head gasket you can get that maintains a .040-.044 quench distance (yes check ALL your clearances)

 

http://www.crower.com/misc/cam_spec/cam_finder.php?part_num=00322&x=34&y=8

 

http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=114681&lvl=2&prt=5

 

ID also do the following mods

Id install a tapered collector extension that slowly reduced & extended the collector exit dia. and added a minimum of 12 inches to the current collector length

 

http://www.holley.com/11752HKR.asp

 

 

ID swap to caltrac bars

 

http://www.hotrodsandhemis.com/Traction.html

 

and install a 4.11 rear gear ratio

 

[b']the CALTRAC BARS and the cam SWAP are basically mandatory, the rear gear ratio and header collectors help but are less important[/b]

btw this may help

 

http://www.ramairbox.com/kits.html

 

and this

http://www.professional-products.com/manifoldsProductSBchevy.php (#52031)

 

those mods will get you much closer to the very low 12 second range, adding this also will get you into the 11s

 

http://store.summitracing.com/partdetail.asp?autofilter=1&part=NOS%2D02001NOS&N=400047+115&autoview=sku

 

 

QFT although i dont understand the collector exit extension? ill have to look into that.

 

i have a similar motor (69 010 canadian block) now i know what i can expect out of it mid 12s will be nice.

 

i donno about no2 though.

[grumpyvette]

lengthening the collector and tapering the exit to a smaller dia tends to lower torque peak rpm and widen the torque curve, both help mid range pulling power, your 1 7/8" primairies are too large in dia. for the ideal power range at that gearing and compression ratio,and this will help

 

http://auto.howstuffworks.com/question172.htm

 

http://www.burnsstainless.com/TechArticles/Theory/theory.html

 

http://www.thedirtforum.com/headercalc.htm

 

http://www.rbracing-rsr.com/runnertorquecalc.html

 

http://succ.shirazu.ac.ir/~motor/page7f.htm

 

http://pweb.jps.net/~snowbum/InExTuning.htm

 

http://www.spectrum5racing.com/Technical/s5headerRevA.pdf

 

if your really serious, addinging something like this adds mid rpm range power also

 

 

welding these to the end helps also, as it noticably increases the scavaging once the exact length required is tested and found

[Mike C]

Your car is so similar to mine it's amazing except for the cam and I've always run my car on street tires. First thing I would do is a cold air intake. I have the factory cowl air cleaner. The air cleaner and an underdrive pulley took my car from 13.0s to 12.7's.

 

Get rid of the little cam as noted, go to a mechanical roller in the 250 degree duration range on 108 lobe center ~.540 lift or so. Add more gear, 4.10's are ideal. 28" tires get more rubber on the ground as well and are also suited to 4.10's.

 

Victor Jr with a 1" spacer. Leave the line at 3500+, no need for the dual plane intake. Your current carb is a good choice.

 

Cal Tracs are also an excellent solution, but plenty of cars run in the 9's and 10's on slapper bars. Poly bushings are a negative in the front, but a plus in the back. Get the car to sit level if no slightly nose high. Align for the strip with camber set with a front rise like it is accelerating.

 

Tons of other things you can do, but this gets you on the way.

[boodlefoof]

Hooray for first gen Camaros! I have a '68.

 

Lowering that 60' time will help you out a bit. Most of the first gen Camaro guys I see in the 11s are running down in the mid 1.60s... but then again most of them are running automatic transmissions. Many are running SSM Lift Bars with success as well to get the times down. You should also be able to fit 28 or 29'' tires in those wheel wells and get a bit more grip.

 

I agree that with that cam (same cam I have in my Camaro by the way) you can get lower into the 12s, but you would be time ahead switching to a solid, flat-tappet cam in the 240* range, and topping the engine off with something more akin to a Victor Jr. manifold.

 

The 462 heads are a very good factory head from that time period. I can't really say how well they can be made to flow, but judging from the past timesheets they seem up to the task! I would still think that something like the Dart Iron Eagle 215cc head or Pro Topline 200cc head may flow better. (sticking with iron to maintain your period-correct look). The intake runners on the 462 are only around 165cc from the factory...

 

Also, if you haven't been over there... www.camaros.net is a really great site for first gen Camaros. There are loads of guys in the 11s and many have posted their setups. Check out the forum and do a search.

 

Off the top of my head, a user who goes by "Eric68" has a combo that might interest you. Pretty streetable 383 pulling low 11s if I remember right.

[Alf]

Thanks for all the replies, there's alot of usefull information here. I made a mistake about the header tube size, they are 1 5/8". I'm getting excited for summer now, I can't wait to get done school, go home for the summer, and tinker with my lonely 69.

 

The good new is that I am planning on pulling the engine out when I get home due to a blown head gasket and a leaking rear main seal(I can't stand leaks). Hopefully the head and block are okay. More good news is that I have a Victor Jr. manifold just laying around. I plan on using the manifold and one of the cams Grumpy suggested, is one better than the other? I also understand that I am a far way from the 11 second barrier, but these times were recorded on an extremely humid and hot day, so I think she has some more in her.

 

Hey MikeC, are you talking about the cowl induction air cleaner and hood? If it works that good i'll have to look into it because I have the hood just not the air cleaner setup. How similar is your car?

 

Here is a link to a 12.90 pass on the same day, just to give you guys a visual. Constructive criticism is encouraged.

http://videos.streetfire.net/search/69+camaro/0/510C02F0-FC89-44B0-83B6-F96D054FD907.htm

[grumpyvette]

http://www.crower.com/misc/cam_spec/...00322&x=34&y=8

 

http://www.cranecams.com/?show=brows... 1&lvl=2&prt=5

 

 

theres not a huge diiferance, personally I usually sellect the CRANE CAMS version, simply for the slightly greater lift and slightly lower duration as your compression ratio is marginal for an exact match to the cam and your running a 3.73 vs the 4.11 rear