I am working on a 89 z28. I bought this as an uncomplete project from another guy.

Heres what I have got so far. It has a engine swap from a 95 Buick Roadmaster. (The Iron Head 350 TPI) The motor was swapped completely wiring harness and all from the roadmaster
A 400 tranny with a shift kit and 411 gears. Time slip cant really remember of the top of my head but i think it ran 14.00 at 104 mph.

Anyway the motor is week and I want to go with 383 at least and maybe come back later and supercharge it or turbo it. I am thinking about ordering a short block and reusing my intake and heads, however heres my first question (if your still reading)

I know i want to go with a four bolt main (so i am gonna scrap my engine block and just order me another) Now for the heads if i wanna go with the aluminum and keep the TPI intake which setup should i be looking for? I know the vortec setup wont work

here are some pics. also i wanna reuse the headers that i have. so i am thinking that i will need a block between 87-96. plz correct me if am wrong. i got a ton to learn and i think i have found the right place

 

 

hey keep that engine!!!!! that is an iron block lt1!!!!!!

great motor. i know that with a stock intake and heads ported to the max you can have 400+ rwhp roughly 550+ crank!!!!

 

well let me say thats with camaro heads and intake. look up ssean92 he had a 95lt1 with 450rwhp dont scrap block you can get splayed 4bolt capsand convert yours to 4. my opinion that is stronger

 

yeah from my understanding this is a dulled down version of what was in the camaros. its got iron heads and straight plugs instead of angled. Also i think it is just a 2 bolt main. I may be wrong. I wasnt gonna just scrap the block tho. thanks for the info. I am listening

 

All LT1's were cast iron blocks. The Vette and F-body versions got aluminum heads.

The only advantage of the aluminum heads is weight. The cast iron heads will make just as much power.

 

well there you hear it. from five7kid. thats a great! motor in my opinion to start with

 

yeah the iron heads have a cult like following it seams. they just weigh more and are less likely to warp. thats why i wanna keep this bulk of this setup, but if it costs a lot to get them worked i may go aluminum

 

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yes i hear you on that but heads are easy enough to get. who cares on the 2 bolt main? you can convert easy to splayed 4 witch is stronger than a plain 4 bolt i belive.

i have a friend with a 96? z28 with a lt1. it has 708RWHP! on the dyno with juice he has a torque spike of over 1100ftlbs. drag/show car. its insane....


anyways. he talked me into a lt1 and thats what i am going to put in mine.

 

you can prob pick some up for not too much. but i think you would be happy with stock alum heads ported to the max. dont know enough about the iron tho. prob do same thing.

 

Splayed 4. I am researching this! thanks. like i said i am listening cause most of you have forgotten more than i know. he running that motor on pump gas?

 

another question i have. are you sure that is a th400?

 

Looks like one.

 

would that not cause computer problems with the lt? and so he must have an aftermarket crossmember?

 

I am not having any computer problems with this setup. and yes there is an aftermarket crossmember and drive shaft is new

 

4 bolt mains are overratted unless you're twisting it 8k or more

I know several guys who have turned 7k with the standard f-body 2 bolt block and had no issues

look at this one here, a buddy Knoxville with an Impala SS with a 383 watch the videos and I think you'll like what you see.

http://www.youtube.com/user/LeadSSled

 

now that is sweet. is that all motor or with a f/i or little juice?

 

Under the video it said a 125 shot of nitrous.

 

ok had to scroll down and i woulda caught that

 

That video make me excited about the 383 I'm building for my ride

 

i was advised the 383 is the way to go (price, availability and power) for street legal/occasional strip by my father who has been bracket racing and NHRA circuit racing for more than 30 years. I cant argue with that. I am pretty excited myself. I am ordering my short block friday i hope

 

What heads are you going to run on the 383?

 

thats a real good question as i havent decided on heads and cam setup yet. . . thinking about just sending my stock ones out to a shop and having them reworked and getting me a good cam. This is my 1st build and i am not looking for too much

 

well if you di not know you need lt specific heads because of reverse cooling . Last i checked any decent afr head was over 1k

 

yeah "FIVE7KID" knows his stuff, the only flaw I see is he's from Colorado and most likely an Avalanche fan... ... GO KINGS!!!

 

For best bang for the buck, find some aluminum head cores and have AI port them out. Their 200cc package i believe holds the fastest LT1 times. Its a great setup for a 383 street/strip fun car but the cam/compression required is not good for a blown/turbo car.
Aluminum heads are much easier to port

 

yeah i may end up with my stock heads

 

the only option i would have there would be to find them off a vette, SS or a trans am right? for a core anyway

 

well if you di not know you need lt specific heads because of reverse cooling . Last i checked any decent afr head was over 1k

 

i just looked at my post. Why did i say iron block? I ment head

 

yeah i think we all know what u meant, cause i didnt notice it myself actually. now as i go back and look at it five7kid caught it

 

Moved to Colorado from San Diego.

Don't pay much attention to the NHL. As Rodney Dangerfield observed, "I went to a fight the other night, and a hockey game broke out."

I assumed you meant heads, but thought I'd better make sure it was clear for posterity.

 

Here's one for you... The engine that was in my car when i bought is seems to be out of an 87 Vette, according to the casting numbers on the block and heads. The previous owner pretty much demolished most of the internals but the block (4 bolt, 2 pcRMS) and heads are still good. I want to go with a 383 rotating assembly and reuse the heads, intake (Edlebrock performer air gap) and carb (Edlebrock 600cfm) for now. The heads are aluminum, 58cc and with flat top pistons should produce 11.7:1 comp. Basically what I want to know is am I wasting my time trying to use these heads? I dont know any other specs on these heads..not much info out there. Just wanted to see if anyone had any insight before I took these things down to the head shop.

I also have a 700R4 trans that seems pretty fresh to go behind this mess... Still trying to decide what I'm gonna do out back in the rear....on a seriously tight budget.

 

11.7:1 .. wouldn't you be past the threshold of using the highest octane available at every corner? I think you'd have to use octane booster, wouldn't you? I've been talking about a 383 Stroker with a 11:1 ratio and most people say I should be fine, anything higher will call for higher than 91 Octane... I really don't mind either way though, this car will only be driven a couple of days a week anyways...

 

This car will mostly see strip and maybe a few miles of street, so yes I will be on racing fuel or a crap load of octane boost!

 

Stock 87 vette heads on a 383 will not be a great combination. They will choke that motor out. They need ported or go aftermarket. Even ported they are limited

 

What would you recommend to look for considering a tight budget?

P.S. your ride is SICK!

 

Uh, jjaungst, you have your own thread going on your questions. It's off-topic here, since this is an LT1 and other than the stroke, won't have anything in common with your situation.

 

My bad...signing off

 

Hey, no need to go away mad. . .

Just saying keep the discussion related to LT1's.

 

but if the same were asked on this lt1 i would say use those heads and port them andget intake ported to match.

 

if ur talking about my situation. so far that is the way i am going.

 

and as far as budget goes one idea would be got new pistons reuse rods and get scat stroker crank. I would build it to make power up around 6k? Because of the gearing of trans and rear. It can be done on a stroker but be carefull

 

a good stall will help too. If someone does not agree chime in these are only ideas

 

well those rods would make it shy of 383 but i heard from a friend if you put 6 inch rods you can get piston slap

 

running 2800 stall all ready

 

And also that rod length has nothing to do with cubic inches?

 

i thought it did? so why a 6 inch rod in a 383? i like a shorter rod for clearance and safety?

 

this is what ssean92 did with a t56 i wanna do a build like this





95 383 LT1 450 rwh from pan to intake

95 lt1 block

SRP Forged Racing Pistons Flat Top +.030 1.125 C.H.

EAGLE SIR 5140 FORGED STEEL RODS 6.0 Full Floating Pin

Eagle 3.75" CRANK 1 PC REAR MAIN SEAL

Blue printed / INTERNAL BALANCE

KING BEARINGS AND MOLY RINGS FILE FIT

Block Machined for most standard base cams.

Block was "0" decked (I figured 13.4ish:1 compression) w gaskets I am running

Melling 55hv oil pump

Billet 4 bolt splayed caps

Crane Cam 234@.539/242@.558 (1.5 RR) 112 LSA 2000-6800rpm

Comp OE replacement Roller lifters

Heads

Stock lt1 heads PORTED POLISHED to the max.

2.0/1.60 stainless steel valves

Comp (new Batch) BeeHive springs

1.6 Pro Comp R/R

Smiths Racing Push rods

Intake

Stock Fully PORTED POLISHED Gasket matched( painted red and cleared)

TB holes milled for 58mm

Lingenfelter Billet 58 mm TB

TPIS adjustable Fuel pressure regulator

Summit fuel rail mount Fuel pressure Gauge

Lucus 42 lbs injectors


Canton 7qt racing oil pan
Aftermarket Mini starter
electric Meizer water pump
GM Opti

 

6" rod in a 383 makes for a lighter piston which is much better for serious rpms. They usually clear just fine, but sometimes hit the cam. Small base circle may be necessary on some setups, but i'd do it anyway and get a healthy cam with near .600" lift to match heads like extensively ported LT1's or AFR's/similar.