aweTastic

Ive read all the articles I can find about this subject plus some because of my concern and ive talked to people about my build but this is where it all really comes together

I tore out my 305tpi (LB9) cuz i spun a bearing (try not to stop so fast for so long that you starve your oil pump lol)

I am building up a late gen roller cam 350 and putting my LB9 heads on it for high compression

This is being built so I can crank up my low end torque

basics of my build

Stock bore gen I 350
Stock 350 crank
Flat Top Pistons
High perf race H rods
Stock 305 TPI intake manifold/runners/upper intake/tb (same as 350)
im looking for a cam in this range 212/218 duration 110 LSA .488/.495 lift (thanks attila)
stock manifolds for the break in then hooker shorties after
AIR injection delete

Ive read that Im gonna need:
new knock sensor
new esc module

now with 305 heads im gonna have near 11.5:1 compression and i have an adjustable fuel pressure regulator that push my 305 injectors to 20lbs and im tuning the prom anyway so im gonna set it to work until i can afford new injectors so that eliminates injectors and the prom tune is assumed...

now my main questions are:

will the 89 350 tpi knock sensor work this massive compression? cuz its supposed to detect detonation which will be crucial to have done correctly cuz of my compression

and...

will the 89 350 tpi esc module work with the different heads? cuz ive read that they just need to be swapped for the 350 swap but i am scared the 305 heads may change how that is affected

i know both of those work together so if the knock sensor wont work what will and will that cause problems with the esc?

otherwise all other changes are accounted for and will be tuned out

Thanks for your help

rgarcia63

If it's a 350 block you need the the 350 KS, and ESC module, has nothing to do with compression, or heads.

TPI

Im afraid even with the 19lb 305 injectors and the AFPR pushing them,
that is not a very good thing to do necessarily. You still might be lean,
maybe not when it is cold or @ start up but, closed loop it is very
probable it could run like a pinging dog, I had almost nearly the same
issue with my 081 sbc 350.

You reusing the LB9 heads? Depending on year they are either the
perimeter bolt 416's or the center bolt 081's. Seems to be a common
topic recently.. Even in the general tech/engine forum.

If they indeed are the 081/416 305 heads.. they hardly qualify as
"massive" compression when seated on a 350, still its something.
They should not cause your car to go berserk.

I think ull be surprised how throaty it is

aweTastic

I was just curious about the KS cuz I figured the compression might throw off the readings it picked up and know that the KS went hand in hand with the ESC so if the KS had to be different needed to know if it would work with the ESC but if the compression wont affect it then Im good =D Thank You



well I know 11.5 isnt massive as compared to a race car cuz my buddy runs 14.5 in his mini stock but for a daily driver street car 11.5:1 is kinda high. High enough to raise a concern anyway =P

and yeah Im rebuilding my 081's and yeah as far as the injectors go since the compression is high and it will be tuned for 19lbs and its actually running 20lbs it will still run good but dont get me wrong... I plan to upgrade to 25+ lb injectors when I add my 1.6 rocker arms but those are waiting for my wallet to get a bit bigger =P

and yeah the motor is gonna womp like some of the old hot rods =D
the goal of the build is low end torque and some nice sound =D

TPI

Assuming the cam is within reason, it should have a great idle
and a buttload of torque. a MAF TPI car wont really notice the
change in heads as much as you think it will.

Hell, Im willing to bet the car will run on the factory LB9 prom.

aweTastic

My cam will be around 212/218@.488/.495 110LSA
im thinking possibly a ZZ4 cam cuz you can find em cheap but ive been told its not ideal for my build
but either way itll be nice and lopey with a good grumble

and yeah the torque is the biggest concern I wanted to get it as high as possible without sacrificing drivability for alot of reasons so i sat down and figured the best way to do it

and about the prom... Im really not sure... Idk all that much about how the factory specs will take it or what will affect what but a good friend of mine tunes my cars for a case of beer so it may as well be done to squeeze as much unassurance out as possible but if it runs after I drop the motor in I'll end up driving it to his shop and I'll be sure to post how it ran (or didnt =P) on the stock LB9 prom compared to after the tune

TPI

Yea, it should run right after you drop it in. Quite a bit of lift on the
cam, You plan on refreshing those heads? How many miles are on
those springs?

I was joking about the 305 prom, but it should run well enough
to get to your buddies place with a LB9 tune, you'd be surprised.

aweTastic

heads are rebuilt with brand new springs capable of around .550", seals, seats and retianers 0 miles =P
no valve job though thats a bit over budget right now but lb9 heads are plenty flowing from what i hear... i might get that done when i decide to finally buy my 1.6 roller rockers and new injectors

and if it drives or rides the trailer either way ill get it tuned but itd be nice to drive it after i drop it in lol ill definitely be posting about it after i finally get it in =D

aweTastic

I had to dig this one up but I finally got the motor in the car....
I finally got everything installed and hooked up and went to start it and the timing was off by about a cylinder and after I fixed it my starter solenoid died and it was after all the parts stores closed so Im hoping to start it tomorrow...

Heres the specs for all those interested:

87 L98 Block
Stock Bore
Basics done - freeze plugs and cam bearings and a thorough cleaning and honed

New Standard Flow Standard Pressure Oil Pump

Stock 3.48" Stroke Crank
Thorough cleaning and journals ground down .010"

Stock 5.7" Rods
Thorough cleaning

New Stock Shape Hypereutic Pistons
Brand new and pressed in to the rods

Comp Cams 08-501-8 Camshaft
212/218 @ .05" Duration
.488/.495 @ .05" Lift 1.5 RR
112 LSA

Stock TPI intake manifold and plenum
Fully Ported and Polished

Stock 22lb injectors
new O-Rings

new Clevite Bearings and new Hastings rings
All new Fel-Pro Gaskets

Stock LB9 heads
Thorough Cleaning
valve job, ported and polished

New Springs, Retainers, Locks, Valve Seals, O-Rings
1.5" Full Roller Self Aligning Rocker Arms



If there is anything else Im forgetting just ask
Hopefully it will start tomorrow and I will give everyone an update
Im so excited right now its unimaginable