WS6GTA

Since it costs so much to mod our cars into the 12s Ive decided to install my 87 GTA's 350TPI into my truck and add a fresh ZZ4 GM Performance crate engine to my car. I already have headers and full exhaust. I will be running a shift kit and mild stall converter with stock rear end for now with Drag Radials. Just wondered if anyone else is running a similar combo with carburation and expected quarter mile times. I hope to get into the 12s with a GM Hot cam or possible blower setup.
Any info much appreciated...
thanks

phoenix305

Are you kidding me? you should hit 12's out of the box, some one correct me if i'm wrong. Heres the stats on the motor.

"Horsepower 355 @ 5250 RPM
Torque 405 @ 3500 RPM
Max. Recommended RPM 5800
Compression Ratio 10:1
Block, Four bolt main, cast iron 10105123
Crankshaft, Forged steel 12556307
Connecting Rods, PM rods 10108688
Pistons, High silicon aluminum 10159436
Piston Rings 12528817
Camshaft, Hydraulic roller Lift .474" I, .510" E.
Duration @ .050: .208deg I, .221deg E. 10185071
Cylinder Heads, Aluminum 58cc 12556463
Intake Valves, 1.94" 10168465
Exhaust Valves, 1.50" 10168514
Valve Springs, LT4 chrome silicon 12551483
Rocker Arms, 1.5 ratio 10089648
Intake Manifold, Aluminum dual plane 10185063
Distributor, HEI 93440806
Spark Plugs, FR5LS or Rapid Fire #5 Gap .045
Valve Lash Zero
Fuel 92 Octane
Ignition Timing 10o BTDC @ 800 RPM
32deg total @ 4000 RPM
with vacuum advance disconnected"

JesasaurusRex

iTrader: (3)

traction permiting and maybe a steeper rear ratio (donno what ur running) should be able to new high 12s, low 13s

mdricken

I hit 13.85 but had 2.0+ 60' times and also have a 2 1/2" exhaust with shortie headers (pretty restrictive).

BUT this was running in OD letting it shift by itself and also with 3.23 gears. This engine pulls like a MOTHER between 4800 and 5600 rpm (right after my tranny shifted).

So I guess with your good exhaust, good traction, big enough carb (670cfm+), big gears and shifting manually you might do low 13s.

I wanna know if you can hit 12s!

WS6GTA

Im surprised you times arent lower with that combo. Im running a TPI 350, stock tranny, only 77K on car, Mods are longtube headers, full 3" exhaust, no AIR, A/C, or smogpump, ADS #24 injectors, MSD Coil and wires, cooler T-stat+Fanswitch, Hypertech chip and Dragradials lowered to 13psi. Last friday I ran a 14.5 with this setup and a 2.0 60Ft. It pulls real hard off the line with the dragradials but falls short of your ET due to lack of HP. Im sure with exhaust and added traction you could tweek another half second out of your car easily. Of course a HOT CAM would wake her up too!

88gta305

Sorry to burst any bubbles, but I have a carbed ZZ3, 345HP crate engine in my corvette with 3.55 gears and a turbo 400 tranny. It runs low 14's n/a, but runs 12.7's with 100 hp nitrous. The ZZ3 is a ZZ4 but only has 9.6 to 1 compression ratio and has GM pink rods instead of the ZZ4's powdered metal ones. It takes a lot of power to run the kind of numbers you are looking for. BTW, the ZZ series of crate motors are extremely solid powerplants and very robust. However, with hypereutectic pistons, I would think very carefully before exceeding 100 Hp worth of nitrous, and the compression ratio on these engines does not lend itself very well to any kind of forced induction.

Cheers guys

Richard

Orr89RocZ

iTrader: (20)

77 vette weighs more than a thirdgen.

355hp as advertised will push a thirdgen into the 12's easily with the right stall/gears and slicks/drag radials.

if you cut a good 60 fooot you should be high 12's somewhere. a decent 60 foot will make you got low 13's, but it all depends on what gears you have in it, either 2.77 or 3.27's. 3.27s should run better than 2.77's and could do low 13's or capable crack high 12's.

i think 3.70s would work great for that motor in the 1/4 with a 3000 stall

mdricken

Yeah definitely ditch the sub 3.73 gear ratios!

I have 3.73 and it is working great because I am running about 5300rpm at the top of 3rd by the end of the strip.

paul_huryk

Even a car with a restricted ZZ4 should push out 300hp and get well into the mid 13's at about 103 or so. If you can get it to the 435hp rating it gets from GM, it should be able to run 12.80 to 13.10 with traction.

TTA850

I dunno if it helps but a freind of mine runs a ZZ4 backed by a TH400 and 3.73 gears in a 78 El Camino and has gone a best of 13.11 at I belive around 103-104 with 1.8x short times. Not sure what it weighs but it's a full streetcar with ice cold a/c and all.

HTH,
Steve

79vette

Well I dont have a zz4 but I do make 310 rwhp with my small block. I did do some serious weight reductions on my vette since it now weighs about 2900 lbs. I havent gotten to the strip yet but it is quick, my guess is high 12's compared to street drags against proven low 13' sec high 12 sec cars.

IHI

iTrader: (1)

350hp that is flywheel rated, NOT rear wheel rated. Factor in the parasitic drivetrain loss, and the "typical" car weight and you'll be mid 13's with a great tune, but more apt for high 13's.

My first 355 was right at 350hp according to my weight/ET/mph on many different calcuators. When I first took it out is full street car form it ran 13.70's. After stripping everything off the motor except alternator, upped gearing to 3.73 with 27" tire, 3600 stall and race weight of 3440lbs in GREAT FALL AIR at our HNRA track with maximum downhill grade allowable I ran a 12.74. On typical days was 13.00.

Not too many street cars/daily drivers with abosolutely nothing on the motor drawing power but an alternator, so hopeing for the times mentioned above is a real stretch in the "real world"

twistedwedge

Ive got a 87 GTA that had the 305 tpi stock, but upgraded to a "crate" 350 (5) w/ trick flow heads... when the car was heavy (3515) carbureted setup...tfs heads, performer RPM intake and junk azz holley 750 I went 12.15@115. Now I know you were wondering about 12's...but based on the mph of my pass...I easily could have gotten 11's. I had fun with some mid 11 sec rustangs on the street before I ran this...

Orr89RocZ

iTrader: (20)

my stock 350 TPI with headers and 277 gears pulled 13.89 at 96.6 with street tires and 2800 stall

and i am lucky to have 260-270 crank hp if that. who knows. full everything tho, emissions/etc, full interior, all that

i would hope that a 355hp crank motor swap into a thirdgen would only have just the bare essentials like altenator since it comes pretty complete. that should be well enough to push bottom 13's at the least.

five7kid

iTrader: (14)

I've almost got a ZZ4 - actually a rebuilt ZZ3 with all the "right" ZZ3/4 stuff but the aluminum heads. My heads are ported iron Worlds, I've got headers, CC carb, we'll see what it will run.

It's far from "optimized" for drag racing - full accessories, moderate stall (probably a few hundred RPMs short of the powerband), highway 2.93 gears. And, I'll be running it at 5800' elevation.

I'll let you know what it runs.

unknown_host

iTrader: (1)

My car went 12.88 with the 350HO, I don't see why the ZZ4 couldnt do that.

Lo-tec

My old 350 (used wrist pin knocking warranty motor out of a 90 cadillac fleetwood brougham) went 13.61@101.5 with a 1.91 60' with minimal mods. This used 40K motor had a crane TPI cam (.452/.465 with 214/220 on a 112, 3 deg. advanced) and normal bolt-ons (cheap shorty headers, performer intake, exhaust) and 3.73's. Stock 700r4 and stock stall from an 88 GTA. This motor had the crappy swirl port heads and ran awesome for an "el cheapo" special.

You'll have better heads, cam, and intake, so there's no reason with good traction and optimal gearing you shouldn't be able to dip into the high 12's with this setup.

five7kid

iTrader: (14)

Well, my clone ran what you see in the sig. 1st time out, off the street except for plugging the thermovac on the air cleaner and emptying the trunk. I didn't even check tire pressure.

With skinnier front tires, modifying launch and shift points, I'm sure it would do better. Then, with real performance gears, a little higher stall, stickier rear tires...

Ray87Z

Last couple ZZ4 dynos I saw as installed in a car put the rwhp around 260-270 if I recall correctly, bit short of the power to run 12s in full street trim IMO... It's 355hp crank rating is somewhat inflated IMO, w/ dyno headers and no accessories I believe. You stick the GM TPI setup on top of the ZZ4 without many mods and mid 13s is about the best you'll see in a full weight street setup car.

Perhaps a better choice would be something like the ZZ4 shortblock (I think you could do better for cheaper w/ a mailorder rebuilt shortblock setup or getting one rebuilt up yourself at a local shop though) w/ some good Trickflow or similar affordable aftermarket heads and the HOTcam or similar.

Wouldn't surprise me at all if the 350 HO crate actually outpowers the ZZ4, the L98 heads are pretty lackluster unported....

slohand

with the understanding it's all just a WAG until you get the slip....

i have the 350crate vortec engine and while i am not quite ready to hit the track i am walking all generations of mustangs, honda s2000s etc. also ran down a lt1 TA twice and just smoked an audi s4 from standing start to about 80 by 3 car legenths with him nailing the gas first.

the audi is listed in the mid 13s in the quarter so i would have to think very low 13 or a real hi 12 should be somewhere in there since the engines are listed at similar HP. should be especially true with decent gears. i am doing all this damage with 2.77s!!

anyway, good luck and let us know how you do.

mdricken

My best was 13.799 at about 99.9 mph at Cedar Falls raceway a week ago. That was with an awesome (awesome for me) 60' though. Dont remember off hand but I think it was 1.7.. have to look it up.

That was shifting manually with 2 1/2" headers w/cutout open

I let her shift at about 5900 rpm and let it run in 3rd till the end of the strip at which it was about 5800 rpm.

It was all dependent on the 60' hookup though. The motor seems to be very consistent when everything hooks up right.

So most of the time I was in the 13.8-13.9 range, depending on hookup.

Gotta get me some slicks now

92droptopws6

iTrader: (10)

i have done soooo many zz3/4 swaps back in the early 90's all of the ones that were raced ran mid to hi 12s infact the fastest was a 91 ta,3.42s,2400 stall,vette servo and valve body,alum drive shaft,edelpoop runners and base,ported plenum,1.6 rockers,58mm,30lb inj.,hooker 1-5/8 shorties,flowmaster cats back,crank&alt pulley kit,crane adj.reg,k&n cone filter and a perf.resource chip.the car ran 1.71 60' and 12.20s on COMP.TA's(245/50/16)
the slowest was 12.87 89 iroc w/3.27's....
back in 91 phr magazine did a write up using the zz series engine they did a 69 camaro quadrajet(tweaked of course) longtube headers,dual exhaust,muncie 4spd,4.10 gear and slicks the best time they were able to get was a 12.6 not bad as far as i see it.
as for the use of nitrous on these factory marvel motors efi style can handle 150,carb i would say 125....i destroyed a zz3 on a 175hit the hyper pistons get with this level of dope live and learn i guess,did not cost me a penny only labor,WARRANTY.......................