casebaseball205

lookin to do a swap this winter. whats advantages and disadvantages of each? which would you prefer?

Psycho_91Camaro

EVERYTHING on the LT1 is better.

383vert

Minus the OPTI

casebaseball205

so is that the general outlook on it?

Lt1 > 350tpi?

irocznickv8

isnt lt1 basicly the same as tuned port just a little better correct me if im wrong

tpi-hearse

iTrader: (27)

lt1 HAS ALLUMINUM HEAD AND 275 HP STOCK!!!!

TraviZ

iTrader: (2)

HOLY CRAP!!!

LT1FUN

The reason's for the horsepower difference between the two are the following.

The LT1 had a more aggressive cam. It had better flowing heads and a less restrictive intake design and exhaust. Basically, the LT1 makes more power than TPI for the same reason the LS1 makes more power than the LT1 etc. etc. etc. As technology advances, each generation of small block will be more and more efficient at making more power. That's just the way it is.

Having said that, you can make any motor make more power than you'll ever want/need. All you need is time/money and the know-how. Or atleast just time and money and let someone else build the motor for you

If you want to run with stock LT1's

Pick up an aftermarket exhaust, a set of big-tube runners, and some 1.6 roller rocker's and you'll easily match, and maybe even surpass the 275hp mark the LT1 put out stock. If you can put all that torque to the ground, you'll run 13's easily.

Not that big of a deal, and certainly less expensive than upgrading to the LT1 motor itself.

On the other hand, the LT1, (atleast with the stock intake) has far more potential then TPI, due to the fact it can make power all the way to 6500 where as TPI, even with aftermarket runners/base/ported plenum, will only flow to 5500 at best. Of coarse, you could aways just upgrade to an HSR or do an LT1 intake conversion but after all that, you'd basically be left with an LT1- only for alot more money, so you'd be better off having just got an LT1 to begin with

I guess it all boils down to this. Both are great engines. If you're looking for a daily-drivabe motor that put's out a lot of low-mid range torque, stick with the TPI.

On the other hand, if you want to build up a serious street/strip car,go with an LT1.

TPI advantage's:

- Cheaper to buy
- Lot's of low end torque makes it a really fun daily driver
- Large selection of aftermarket intakes and cylinder heads to choose from
- Great stop-light to stop-light race car (all that low end torque is hard to beat)
- Looks awesome (sorry, I had to throw that in there

TPI Disadvantages:

- TPI falls on it's face at 4800rpm. (5500 with aftermarket runners/base)
- factory cast iron cylinder heads are garbage and weigh a ton
- harder to find a low-milage engine do to their age


LT1 advantages

- 275hp stock
- Aluminum heads (light weight and easy to port/polish)
- intake manifold can make power to 6500+
- easier to find a lower milage engine compared to TPI engine
- best sounding motor short of a 5.0 Mustang's

LT1 disadvantages.

- Not a very big selection of aftermarket cylinder heads (AFR/Edelbrock - the Edelbrocks suck, so you're really only left with one choice...)
- Parts are usually more expensive (sometime A LOT more expensive)
- Opti-spark failures. Though this seems to be hit or miss. Some people have them for years with no problems/others always have problems.)
- Infamous "bogging" at lower RPM 1500-1800rpm. (nobody knows how or why this happens. Nor do we know how to solve the problem. It remains a mystery even today. Just like with the opti-spark though, it's hit or miss on this aswell.

It really all depends on your goals for this car, and how much your willing to spend.

Trust me. I know these things. I own both motors.

http://www.cardomain.com/ride/428479
http://community.webshots.com/user/lt1fun

casebaseball205

im 17 and i got this as a DD but im lookin to redo everytthign again and get a different engine. im planning on buying a winter car to beat up on. so i dont aniticipate it being a DD. im 17 so im a small budget. just lookin to upgrade to something a little quicker and more power. litte more fun to drive too. i would do LS1 but im too poor

i would do basic stuff to both as far as mods, headers, exhaust etc. but nothing too too major.

so with that said, would the 350tpi be a better option for my needs and concerns? as well as my situation with teh car

Coach Hawk

Stock LT1 heads > any other pre LSX factory head, and flow circles around even the infamous "double hump" Fulie heads. The aftermarket head choice is so limited because the factory heads flow so well as is. The ONLY advantage ANY aftermarket LT1 head has over hactory is that it had more meat around the ports for porting.

The STOCK LT1 bottom end will handle 6800 RPM repeatedly and not think twice about doing it. I have a friend with AI heads on his 95K stock shortblock. He's putting down consistant 12.6's in a naturally aspirated 4300 LB Caprice with his completely streetable combo(drives 350 miles a week to and from work).

At this point, the LT1 performs better in stock trim, and has more potential than any factory Gen 1 engine ever did. As far as the Opti thing, mine is the origional 100K opti, and I know many others who have atleast that many miles on their origionals as well. It's only REAL drawback is the rotor, which tends to explode over 6500 RPMs. However, MSD just released their Pro-Billet Opti, which has a much improved rotor design and so far looks to be a very quality piece. Everyone I've talked to that has one loves it.

Klortho

Take a set of heads, send them to Lloyd Elliot and have them ported, will flow a whole bunch better than alot of the aftermarket units for around the same money. I personally have not had any opti problems yet nor this 1500-1800 bog, but then again, my car rarely sees that low of RPM's. The LT1's are imho a much better setup than the TPI engine, just because of the afore mentioned problems with the TPI's. ssean92 took his car to high 13's with a stock LT1/6-speed and 3.73 gears. No way would you ever see that with a stock L98-TPI car. I would bet to say if he could have gotten the power to the ground, mid 13's easy.

88blkbird

Klortho, how much does Lloyd Elliott charge for the porting, I have purchased a couple of engine performance books that give a reasonable overview of basic porting and the basic principle is the same in all cases. I also assume you are speaking of sending him aluminum heads,i would imagine the iron heads on my new Lt1 I would would cost more to port and ship.

WhiteBlaze

iTrader: (1)

Lloyd's Site

koll

Personally I would do with a built 350. Put a nice set of AFR heads, a decent cam and a holley stealthram (and perhaps stroke it to 383) and itll whoop on any stock and mildly modded lt1.

Klortho

But why take and spend a bunch of money on a 350 to whoop up on a stock LT1 when you can get LT1's at a reasonable price, put that money into it and be able to whoop up on LS1's. Then again, with all of that money, you could buy an LS1 and put in the car........see what I mean it's endless on what can be done, just depends on how much money you want to spend.

With a TPI car, you still have batch fire, TPI limited torque and just another TPI car that everyone and their brother has. Do an LT1 or LS1 and be one of the few that have this and keep the rest of the car stock looking. That way when you whoop up on the TPI car they start to wonder wtf was that?

Also, unfortunatly the LT1 that LT1Fun has is the worse year for them, '93s were awful. SD setup instead of MAF, the non-vented splined opti is a pain in the butt as well. '95s are the best year to get, they are MAF setup, pinned opti so it's impossible to get it out of time if you need to change it, both the '94 and '95 models the PCM can be programmed instead of having to flash a chip for the car.

Not knocking the 'bird LT1fun, it looks sweet and I almost bought a '93 new in '93 and after reading everything I have about them, I'm glad I didn't.

casebaseball205

so it seems like the generla thought is to save up the few extra bucks and build up an LT1? i just found a POS car to drive around so ill be takin teh bird off the road in september so ill have all kindsa time to do stuff.

gotta love 95 escorts

BigDreams92

iTrader: (1)

Come up with a no bull budget. After seeing where your bottom line ends then see what you can do with it. Don't start something half way then have it nickel and dime you till you're pennyless. I have about $4500 invested under the hood alone, and that's cheap compared to the price of some of the other set ups.

LT1FUN

Well, I've never heard any complaints about the '93 until your post.

I'd have to respectfull disagree with anybody that says OBD1/speed density cars are bad. Total opposite actually, in my experience.

OBD-1 and speed density allowed for so much to be done to my motor without requiring a tune, it was ridiculous.

I know a lot of guys with the later mass air/OBD2 cars and they couldn't do 1/4 the mods I did on my car, without having their rides, run like crap.

There were a few odd quirks here and there when it came to ordering parts for the '93 model year, seeing as how that was the first year of the LT1 in the Fbody cars, and GM hadn't really "finalized' the design of all the parts just yet. "Some parts on the '93's were specific to that year only, but it's not even an issue, just a matter of ordering a different part number, that all.

From my experience, and the experience of the few people I know who also have the '93's, they were actually the best ones to have.

It wasn'ty until I was making 360+ at the wheels on motor, did I start to have a bit of an issue with a stumble juist off idle. Nothing major mond you, just a bit annoying.

Meanwhile, friends with '95 and up cars ,were haviong issue's all over the place after just a few mods...

One more advantage of the '93's is that the ECM is not soldered in, so when the time actually comes that you do need custom ECM programming, you could always just pull it out and replace it with a new one, or get a "piggy back" chip from places like PCMforless and never have any down time on the car. You literally just plug in the harness and the custom chip to the origional ECM when the custom one finally arrives.


Forums like Speeddensity - Powered by vBulletin give you all the information you need to know about these cars.

Again, I don't know where the idea that OBD1/Speed density is bad, but that's far from the truth.

Ever notice that every aftermarket F.I. set-up is all speed density?

It's easier to tune and can except a lot more mods before it needs additional tuning.

To each his own I suppose....

Klortho

See, I've heard the exact opposite. The MAF cars accept mods easier than SD cars do, especially when putting cams in. I know this is a fact on my Mustang which is MAF instead of SD and I guess that the rule of thumb came over to the GM motors when people started really modding them. Alot also thought that there was a reason that GM only ran SD for 3 years from '91 through '93 and then went back to MAF was because of the tuning issues and problems keeping cars in tune *shrug* it's getting extremely easy to tune the '94-'95 cars, especially with Bryan at PCMforless, a buddy of mine put a CC306 cam, a set of MTI ported/polished heads and bigger TB on his LT1 and Bryan hit the tune first time and will that car run, it's stupid fast. I guess it's each to his own when it comes to that

JP86SS

iTrader: (1)

MAF can tolerate changes better than SD due to the fact the air is being measured with the MAF and SD has to calculate the flow from the pressure in the manifold. When making changes to SD flow, the pressure calculation for the amount of fuel/air will be off due to the different presure drops of less resistance on a good flowing setup. So tweaking back to optimium is needed when changes are made. The MAF has difficulty seeing fast transients in air flow which SD can see instantly. There are give/takes for both.
Both can be tuned to maximize performance if done right.