So the whole idea around this build was to build something that was reliable and still make good power on a budget. In 22 and have had my 1994 Trans Am for 3-4 years now and ive pretty much rebuilt the entire car minus the engine. Ive always wanted to build a built engine but never been able to muscle all the money together as its not cheap and for alot of us takes a long time to save up for. I wanted to have a street car that would make lots of torque down low and not be a gas pump queen but still making awesome power. I ended up getting a low mile forged 355 that was run for not even a summer before the car was totaled. Got a great deal and fit the bill for what i needed to make a near stock compression. Didnt want to have a high compression motor with a big *** cam and be a pain to drive and not make any power on street. This build will include emissions as im from Canada and well theres no way around it unfortunatly so that limits my build aswell. I just sent my shortblock off to the a local speed shop to get looked over and refreshed ready to put some parts to that ive been collecting over the years. I Figure its been about two years getting everything together to this time now where i can start to put an engine together for my car. I know im talking to much and its time to let the parts do the talking.

My Car:

1994 Trans Am M6 - 356,000KM!
Ram Air
AC Delete
Pacesetter LT
Pacesetter Catted Y
Borla Catback
UMI Tubular Adj Lca's
UMI Upper & Lower Adj Panhard Bars
Spohn & UMI Custom SFC/Torque Arm Track Pack Setup
ST 25mm Rear Swaybar
Stock 10 Bolt with 4.10 Gears

My Build:

93’ Built 355 0.030 LT1 Shortbock - 4k Miles
Mahle Powerpack 5cc Forged Pistons
Eagle Forged 6” H-Beam Rods w/ ARP Bolts
Polished and Balanced Stock Crank
ARP Main Studs
Clevite Bearings
Melling HV Oil Pump
New Oil Pan

AFR 190 64cc Aluminum Heads
Fully Ported & Flow 294/208 @ .600”
2.055/1.600 Valves & PAC 1218 Valvesprings
ARP 7/16 Rocker Studs & Isky Adjustable Guides

93’ Intake Manifold – Fully Ported by Lloyd Elliott
Accell 30lb/hr Injectors
Professional Products 58mm Throttle Body
Custom Emissions Grind 223/230 .565/.565 112lsa by Lloyd Elliott
Cloyes Double Roller Timing Set
Comp Cams Pro Magnum 7/16 1.6 NSA Roller Rockers
Comp Cams Hardened Pushrods 7.200 (TBD)
Stock GM Lifters
95’ Timing Cover
GM Delco Vented Opti

10.4:1 SCR

 

I see five uglies.

Why the 93 intake manifold?
Why so low on the compression?
Why a high volume oil pump?
Why h-beam rods?
You are over-headed and under-cammed.

Other than those few things, nice.

 

Yeah I would bump compression a full point

 

 

^ exactly what he said

 

This is not a track car it will be street driven which i why i wanted to stay away from high compression and even if i did bump it by getting a set of 58cc or smaller heads it would put me around 11:1 for how little difference. Cam is small because its the biggest i can go and still pass emissions testing. As i stated in the overview i wanted a near stock compression car with a great street cam and a set of good flowing heads. Im not building an all out monster essiensially built mild heads cam street car.

 

LOL ramair drives his on the street and on pump gas

 

11 to 1 aint high on a aluminum headed reverse cooled motor, but it still should run good

 

If you want an emissions-friendly ride, put a set of stock heads back on, sell off the AFRs, and use the money to invest in something else (suspension mods, etc). You're wasting so much potential with those heads (what with those huge valves and giant combustion chambers) and that baby cam on top of the docile compression. I doubt you'll eclipse ~350whp, if that.

Also, those 93 fuel rails are designed for batch-fire injection, not sequential. There is a definite pressure differential when firing 4 injectors at a time as opposed to one at a time. Less than ideal.

The high volume pump is likely unnecessary with your build, unless the tolerances are loose enough to warrant such pressure. Increased oil pump drive gear wear and more power consumption is the result.

Going from stock compression to say 11.5:1 won't cost you anything in terms of streetability and emissions. You stand to gain a fair amount of HP by upping the compression while still keeping the NOx at a minimum. A good tune and you'll pass emissions just fine.

I missed the Accel injectors too. They are some of the worst injectors available in terms of consistency and flow rate, and this is documented. There's a reason they are so inexpensive. Accel makes some of the worst electrical components around.

Then again, it's your ride. If it makes you happy, ride with it.

 

The LT4 was 10.8 from the factory if that puts into perspective just how low 10.4 is on a performance build.

You are completely missing the boat here.

 

I agree with everything RamAir95TA said. Why go from a 94' intake manifold to a 93'? Seems like a back step? I don't even know if your existing fuel lines will work on that intake. And going from a SCR of 10.4 to say ~11.x will not only give you quite a bit of power, the throttle response with increase.

Also, I'd probably get a set of LS7 lifters instead of using the stockers.

 

My car is running 62cc heads on a stock shortblock. My car is what most guys consider low-compression. I'm quite positive i'm giving up 30-40hp (with my cam) compared to what i'd be at with a 10.5-1 setup. I see you have all of the parts in your stash so you are rather committed. Find out what it would take to mill a few cc's off of the heads and intake, and then run a slightly thinner head gasket. There are very few negatives to running more compression.

 

The block is zero decked so running a thinner gasket it out of the question or i have deeper pockets then i do brains. Doing a quick calcutation going to a 58cc head will put me at 11.1 and 56cc will be 11.4. Milling my heads from stock 65cc to to 56 or 58 is only asking for trouble with intake sealing issues. Guess ill have the play the card and see if i were to sell the heads which sucks.

 

Ok neub question... whats the highest CR you could run on a pump gas car? The reason I ask is the guy at the speed shop told me 10.5:1 and I know stock is at 10.4:1.

 

11.5 is pretty much the highest you can run on pumpgas and tune adequately.

 

Lt1s can safely run higher compression due to reverse flow. My old firebird was over 11:1

 

Find a new shop ASAP. I' running ~11.5:1 in my daily driver.

 

No way is this true. There is FAR MORE to octane requirement than just static compression. My compression is upwards of 12.6:1.

 

Bull, there are plenty of pump gas street LT1s on the road over 12:1.
Hell a lot of stock shortblock setups with their poor quench and pistons that can easily be hurt by detonation run 11.2-11.5 compression.

Thought I do think the OP hit the nail on the head when he said.

I would advise changing a LOT of the plan and would endup with a better result for less cash.

 

Ok whats the highest CR you can safely run with a 200 shot 383ci and GM847