baja252_97

The basic fact, a 1992 Camaro 1LE running in the NASA Camaro Mustang Challenge Series.

Long story short, looks like spun a few main bearings in my LB9 motor back in July. Decided to simply order a new long block from GM based upon my "F" VIN code. I had a local shop put the new long block in with the TPI set up from the bad LB9 motor.

With the race season over it is time to figure out how to get the car up to power. The original LB9 was making 230/298 at the wheels. The new motor is at 189/300. I pulled the valve cover to discover the heads are the vortech heads.

Based upon what I could conjure up on the site, both motors are 9.3:1 compression, two bolt mains with flat top pistons. But I have not pull the heads from the new motor yet.

My thought is to move the heads and cam from the original LB9 motor to this new motor? And get it tuned for the new set up (we had to screw with the tuning to keep the motor running). Does anyone see any issues with this?

88transam400tpi

if you have vortc heads i would use them. and if your gonna put a cam in it why not get a better one than stock.and do you know if the new motor has a roller cam i it.

baja252_97

The roller cam is a great question. I guess I will not know until I pull the cam from the new motor. That could throw a wrench into my "easy" resolution".

Why stay stock? Because the CMC rules.

Hawk92z-TDZ

What LB9 has vortec heads stock? It should have 081's being a 92

baja252_97

The original motor that spun a couple of main bearings is a LB9 with the 081 heads and amtching cam. The replacement long block I put in has the vortec heads (187). Now what cam this new motor has, I do not really know.

Azrael91966669

the power drop is caused by useing the tbi peanut cam same cam found in 88-89 tpis

your old lb9 had the "L98" cam higher peak hp but same torque

from what i can tell with dynoing my car and other tpi cars is the tbi heads are not a restriction the issue is haveing the low output cam
with my tbi heads i do get a bit more bottom end off the line then a normal lb9 with 081 heads but the problem is i end up spinning off the line

btw stock for your car would be haveing the other cam
you should be able to put you other cam being that they do not sell a replacement lb9 high output they well just sell you a tbi version its only equal to the low output version of the lb9

Fast355

iTrader: (2)

To get the HO TPI 305 cam all you have to do is specify the L98 as the engine.

baja252_97

But the L98 is illegal in the Camaro Mustang Challenge.

88transam400tpi

i was thinking if they just sold you a low output tbi long block maybe the cam isnt a roller. cause my dad got a 350 long block from auto zone a while back and i remember that it was not a roller cam motor

Damon

How did you accidentally end up with Vortec heads and still bolt your stock TPI setup on it? The intake bolt pattern is completely different and would make installing the TPI system on it impossible without the use of a Vortec-specific lower TPI intake manifold (from Scoggin Dickey). I would also think that non-stock heads like Vortecs would make you instantly illegal in a sactioned class-race like you compete in. ???

Putting that aside, yes, swapping over your original heads and cam will likely give you back the power you are missing.

Fast355

iTrader: (2)

The cam is NOT though, it WAS the STOCK cam in ALL 1990-1992 TPI cars, both 305 and 350.

baja252_97

Well, the original TPI did bolt up to the 187 heads. If the 187 heads were available on any 82-92 Camaro 305, then they are legal. But not sure why anyone would want them (from what I have read).

I will take pictures tomorrow of the lower intake now that the top is removed. I tried to pop it off this evening, but it feels like it is glued down

As for the cam, I already have to the original LB9 cam. It was the bottom end of the original motor that gave out.

InfernalVortex

iTrader: (4)

187s are just lame TBI swirl-port heads, not Vortecs.

Vortecs are generally known to be the 96-98 Truck heads. Im not sure what their 305 head casting numbers are, but it doesn't matter. They're very good heads. They are also not what you have.

You've got crappy swirlports on there, ditch those and put your old top end back on it.

Azrael91966669

my crappy swirl ports do just fine under a tpi setup if not better then with 081s

the swirl ports do very well where tpi makes its power the swirl ports make better power for off the line then the 081s

my dyno # with tpi and 187 heads where 186 hp @ 4100 and 291 torque @ 3000 both numbers are at the wheels sae corrected
id say not bad for a stock LO3 thats burning oil and 120k miles
and i still have the crap lo3 exhaust 2 1/4 other then a free 30 series flowmaster muffer
from what ive seen thats better then most 081 heads with tpi
gm made the swirl ports to be a workhorse for trucks only reason they have a bad rep is what gm put on top
thats my oppinon
i dropped a full second off my 1/4 mile time i dont think the heads are gonna be a problem for him
but i would put the l98 cam back in

InfernalVortex

iTrader: (4)

He had dyno numbers for each setup... I'm not willing to write off those heads as being equal just yet.

But the difference between a stock 305 TPI and 305 TBI is only like 20 or 30 hp... so maybe you're right. I always figured the swirl ports hurt power a lot more than the throttle body injection....

baja252_97

Thanks for the clarification. I have headed down the path of simply swapping the heads and cam into the new long block. It looks like I can do it without pulling the motor.

The one plus side of pulling the motor would be to put a high-flow oil pump and Canton oil pan on it. Might make the new motor last a little longer.

Nothing against the swirl-ports, but I am pretty sure I can get the 230/300 numbers with the 081 and LB9 cam. I had it before.

Kevin91Z

iTrader: (1)

A stock engine doesnt need a high-volume oil pump. I've always used the Melling M55-A which is about 10 psi more pressure at the same volume. Higher volume pumps will require more power to turn them, which takes away power to your rear wheels.

tony_cogliandro

iTrader: (3)

I know that this is an old site, but the topic is what i'm looking for.
I started out looking at everything, to do a complete rebuild on my 90 cam rs, which i bought new in 90 for my wife.
well i started buying and doing things, and did the suspension, the interior, or most of it, and while I was at it started working on drive train too.
but in 2009 the smog laws changed. i was going to dump a 350 into it, but now is not the right time for an engine change. but i already have the hooker 255's and a complete tpi system, including wiring and computer, for a 350.
i know those two will fit on a 350 I was working on, but I want to put them onto my 305. clean up bore, and all that. its tired. i want to keep the same engine numbers just incase the dmv goes nuts here.
im going with a MAG 16829, for the rest of the exhaust and carb approved 3 inch diameter mag cat.
so my question is - what IS A MUST to do to get the tpi on the system as well as the exhaust i have?
I was going to buy a new cam anyway, and i will go hotter, but do I have to get a completely different type. do i have to go roller, to use it with the tpi. I getting rid of the tbi - which i will take off very carefully in case anyone wants it, including the computer.
what is a MUST for this to run well.
i already know about the great article on this board that gives us a laundry list of changes for the tpi from tbi, but its the engine im concerned with now.
any suggestions?
i tried to run a check and this is the closest I could find to the topic.

its a daily drive car so lots of torque and not much on rps - not over 5k, is more than acceptable. like all of you i think its fun to drive and i want to drive it another 20 years.

Kevin91Z

iTrader: (1)

The current engine is a roller cam. You can remove the existing roller cam, and put in another roller very easily. Swapping to a non-roller cam might be cheaper at first, but you'll also have to buy new lifters, a new timing chain, go thru the flat-tappet cam break-in procedure, and use special oil so the cam doesnt go flat. Not to mention roller cams have better ramps and more lift, so they make more power, and are worth the extra cost.
For your 305, a used LT1 cam drops right in. But with the age of your stock parts, you'll want to change the timing chain, valve springs, and valve stem seals while you're in there.

tony_cogliandro

iTrader: (3)

thank you for that bit of information. that goes into the "save it" file as far as i am concerned.
let me impose on you one more time. the next thing i have to buy are heads, to go with that cam, and all the other parts.
i am also going from tbi to tpi.

i have been looking at 23 degree heads as well as some alum vett heads. i reaize the egr cross over problems with the vett and i can fix that but do i have to get different l length lifters for a 23 degree head vs standard heads?
did i ask that correctly?

i also have the ability of getting some new trick flows very cheap - but they are 23 degrees and not the 18 degree ones.

and yes i will pull the engine out and look at everything to see what needs replacing, and will buy new timing chain, etc like you suggested.

i just had to add this. i am reading up on your suggestion and what do i find on the ls1tex.com - the one and only kevin01Z. you get around. you really know your stuff.

tony_cogliandro

iTrader: (3)

Maybe I can ask one more question about the LT cam? It looks like GM had a number of different LT1 cams, and they are all different. The 93 LT1, the 94 through 95 LT1, the 96 LT1, and then it apparently went to a 96 LT4, a ZZ3, and an LT4 hot.
Would you please tell me which one you feel would be best. Someone else already told me that a lobe less than 112 would not be good, but they all apparently fit into that category. So in your opinion, which one would be best?

Kevin91Z

iTrader: (1)

23* heads ARE the standard heads. 18* are race heads. Stay away from those.

You can use your stock roller lifters providing they are still good.

Any of the 92-97 LT1 stock cams are fine. Even the stock 96 LT4 cam. You dont want the LT4 hot cam with stock heads. The ZZ3/ZZ4 would be fine too.

tony_cogliandro

iTrader: (3)

thanks kevin. i have a chance to pick up a used zz4 with the matching valve spring, retainers, locks, cups, rocker arms and screw in studs (not shown in pic but included) that came off a zz4 crate engine with abut 20k on it. Its cheap and i know I will probably need a new timing chain,and a few more things, so it is probably worth it. if not i will just sell it myself. unless you think its crazy to get it.