88-I.R.O.C.

iTrader: (3)

I got an '88 IROC and it has the poor old 305. I was thinking about building a 350 for it, but then i thought, hey, i wonder if i can go bigger...? Anyways, i would like a car that will beat all ricers and keep with the Lt/Ls camaros. I am going to drop in a 6 speed, and gear it up to 3:73. I'm rebuilding all the suspension and everything else as well. Will the TPI keep on a 400? I would like to keep it just for the sake of TPI. I am going to modify the tpi with every trick i can find, but will it actually work on something bigger? I don't really want to run turbos, but a supercharger or more down the lines of nos will probably be in the building plans...

"there's no replacement for displacement"
unless it doesn't fit in a 3rd gen....

Air_Adam

Anything you can build with a (roughly) 4" bore will work. But why? TPI puts a pretty big bottle neck on a 350, and would be even worse on a 383 or bigger.

A supercharger would change that though....

screaminformula

you should consider Holley Stealth Ram...or if you're really spendy, a Super Ram...but a nice Stealth Ram should handle your fueling issue and look a lot like TPI...

Josh

88-I.R.O.C.

iTrader: (3)

I wanted tpi just so it looks stock (never mind the supercharger...). I am restoring the whole thing and would like to keep the tpi more for show.
Where can i find some pics of the stealth or super ram installed?

screaminformula

The Cure For the Common TPI, there is a link for the stealthram.com message boards...

here is a pic of it installed...

sofakingdom

iTrader: (1)

That depends on what you define as "work".

It will bolt up to ANY small block; including the 400, or the even bigger creations that are possible with that block.

The 305 is already choked by it.

Meaning, it's crippling your 305. It will even more severely cripple a larger motor, just like it did the 350s that it was put on. As a comparison, look at the HP from a Corvette L98; and then compare that to the ZZ4, which is the same block, pistons, and so forth, AND THE SAME HEADS; the only difference is the cam (which isn't just a whole lot different), and carb vs TPI.

I suggest you re-define what "looks" good. Me, I'm weird and stupid and all; but to ME, anything that makes a car go slow and can be visually identified, DOES NOT look "good". It looks SLOW. That applies to TPI. TPI looks SLOW. Because it is.

five7kid

iTrader: (14)

In fairness, the ZZ4 crate is rated as gross flywheel horsepower, while the Vette is net flywheel horsepower.

But, Scoggin-Dickey discovered the harsh reality when they developed the TPI base for the Vortec heads, thinking it would be a great seller with the 330 horse 350 HO crate engine. With stock TPI, they couldn't even get 300 gross flywheel horses out of it. They ended up having to go with Edelbrock runners, 52mm TB, upgraded Vortec heads for more lift, and the LT4 Hot Cam with 1.6:1 roller rockers to get above 330 HP (and then overachieved) for their Vortec TPI crate engine. But, with a 750 CFM Holley and RPM intake, that same engine would be over 400 HP for sure.

GodSpeedGTA

iTrader: (1)

id have to say...in my personal views...seeing a tpi setup = restricted motor and slow...i dont care what youve done to the TPI setup...there are plenty of aftermarket fuel injection platforms that outperform the tpi by leaps and bounds and look better to boot

especially the stealthram and its relatively cheap!

88-I.R.O.C.

iTrader: (3)

I gotta say that the stealth ram looks pretty good......I searched for some pics on the internet, but only came up with low res pics of the stealth ram installed. I think i might be sold on the idea.....

Buddy

What is wrong with this board??????? Can NOBODY READ!!!!!!!!
Someone asks a simple question and people respond with WHAT YOU SHOULD CHANGE. READ people! Some people actually LIKE TPI!!! For whatever reason, be it looks, trying to stay sleeper/stealth, originality, whatever.
If someone says "I really like pasta, but I'dd like to know of a couple sauces to broaden my dish. Do you know any good sauces?"
What do you respond with? "Whoa man. steak is much better, you should eat steak!"
Steak is good, pasta is good, TPI is what some people like, Stealthram/Miniram/Superram is what some like.
We don't have to cut a person's ideas down because WE don't "approve"! Just answer the question the best of your ability and move on.
It will help the person out much more. You can give other "advice", but they would appreciate their original question answered, it's what they asked.
TPI can go on anything you want. To not lose too much over other systems like Stealth or Superram - the gap inceaces more - I would say 383. I could be wrong, but I know years ago LPE did offer a 383 with TPI - although massaged - as well as a Superram version. There was a power difference, but it wasn't like 50 hp or anything. Just look at the TPI shootout thread, 383 and many different combos. If your running the street, TPI is a great setup, lots of usable HUGE torque. For the track, you'dd be best to go aftermarket unless the looks of the TPI is just where your heart is set.
In closing, 383 would probably be a safe c.i. to go if you want to stay TPI.

Not trying to get a war going here either btw, just get tired with how almost ALL Thirdgen threads seem to go, this site has actually earned a reputation for this kind of thing. I'dd love to see Thirdgen lose that rep, I like this site.

alvanwie

If you think you are doing this guy justice by answering that way you are not facing reality. One of his statements was he wanted to keep up with an ls1 camaro. It will be very difficult for him to build a 383 tpi to run with the ls1. We all know their are better approaches to get the results he has expressed. The people here on TGO have given him their best advice based on his expressed request.

Buddy

Really??? You think so huh? GM High Tech Performance just did a buildup from RaceKrafters with a 355 using TPI. They got 416hp and 486tq. I think that should keep up with an LS1? SuperChevy mag apparently got even more power, I haven't read the article, but there's a thread reguarding it on here. In the TPI 383 shootout article, TPI did quite respectable in the power department. If you read the GMHTP article, by RAY T. BOHACZ, a bit of a guru in the auto engine world, he is very impessed with this engine. - A 355 don't forget. From 2343rpm-5970rpm the average torque was 454 ft-lbs. At 2400 it had 424 ft-lbs.
Quote:
"SOSN blew us away by producing almost 175hp and 145ft-lbs more than a production version. In addition, the 355 made 15 more ponies and nearly 90 more ft-lbs of torque than the much-lauded C5 ZO6's LS6 engine! I do not care what camp your loyalty lies in, you just have to love this little 355."
End Quote.

Is an LS6 like an LS1??
The people on this board, I'm not bashing everything and all, (I have asked and recieved advice myself) do give advice. But sometimes you have to ask the same question a few times to get the answer. Then people get made cause it's the same question asked, but again, never actually straight -up answered. It's a circle.
"What's the biggest C.I. to go with??? Btw, I love TPI"
"Well, this is the number ___. Oh and here is some other info for you to weigh over in your decision. Hope this helps."
Would that be so hard?

88-I.R.O.C.

iTrader: (3)

What issue is the GMHTP 355 tpi build up in? Or that super chevy article?
I did make the Ls1 statement, but i know tpi can preform, just not as well (or cheap) as other options. You're both helpin me.

five7kid

iTrader: (14)

Yes, when the parameters are undefined.

Consider the original subject: "What's the biggest cid motor that will work with tpi?" As already pointed out, "will work" needs to be defined. Will TPI on a 434 "work"? Yes, to a point. That point will probably be about 4000 RPMs. Could a carb'd 350 blow that 434 TPI out of the water? Probably.

Now, define "TPI". Stock? Modified? What level of modification? Is a Miniram still TPI?

Then, the text deviated from the subject with performance expectations, "...beat all ricers and keep with the Lt/Ls camaros." I know 4-cyl imports that can blow the doors off of stock LT1/LS1 cars. Oh, you say, how about modified LT1/LS1 cars? Again, what level of modification? Undefined. How many LT1/LS1's are still unmodified? How many imports are packing heat these days?

By the time you modify TPI to keep with an LT1, you could have bought and installed an LT1. Then the modifications to the LT1 make it even faster. Ditto with LS1.

How much was the mag TPI engine modified to produce those power levels? I don't know, I haven't seen the article. But, it's a safe bet that if it was NA, it doesn't "look" like a stock TPI, and it wasn't cheap. It's not unlike trying to make a 305 beat 350's and larger - why? "So I can say it's just a 305." Big deal. If you had spent that much money on a 350, you'd be going even faster. Same here, the money spent on the TPI to make it as fast as it is, would make a different platform even faster.

So, yes, it is hard to give a straight answer to questions like that. And, the ugly truth is sometimes people need to be saved from themselves.

Had the question been asked along the lines of, "What TPI-based system combined with what displacement engine would allow me to beat/keep up NA with xxx?" That may not be completely straight-forward, but at least it has some possible answers. Of course, if you want to keep the factory TPI look, then your choices are as limited as the performance you could achieve.

Personally, I think TPI is a good-looking system (known performance notwithstanding, but remember what "performance" meant back in 1985?), and LS1's are pretty ugly (that's why the factory puts a bunch of plastic over the top to cover it up). But, dang, those LSx cars are fast!

kaptinkafeen

iTrader: (2)

Nov 2006 - GM H.T. - p#74-77 Something old Something New Dyno figures

July 2006 - GM H.T. - p#46 -53 Something old Something New Part III

April 2006 Gm H.T - P#20-26 Something old Something New Part II

And I am assuming the Part I of this article is in the previos GM H.T to the April issue.

After reading the article, RaceKraft had done some advanced work to that 355cid block. Cool stuff, but IMO, a bit more than the average enthusisat would care to do, especially considering the cost.

-Andrew

88-I.R.O.C.

iTrader: (3)

True.

Perhaps it would had been better stated if i said that i would like beat most ricers. I know there is some crazy stuff out there.

I like TPI for the looks, definately not for the performance. The stealth ram looks pretty good too though. I've never really seen a good pic of it before. I think i will probably go with the stealth ram, because looks for performance outweigh in my oinion.I thought about throwing a LS1 in there, but as mentioned, they are pretty ugly in my opinion. I dislike plastic cover engine bays. I guess what i'm looking for is a motor that will mount right up where my old 305 was without changing anything and will perform like a champ. I'd like at least 400 rwhp. I know you can do that not too hard from a 350, but the more hp i can get the better. As mentioned before too, I would be better off spending the same money on a more ci motor than less cid. Other mods while i'm into it will be a different rear, t-56, better suspension, plus the other driveline mods that are slipping my mind because i'm thinking about how little $$$ i will have left.

alvanwie

The HSR would be an excellent choice for a 383 with 400 rwhp. I have helped my nephew with his HSR 383 which is at that hp level. The engine is easily capable of running 7000 rpm (his peaks at about 6000 rpm).

If you use TPI you are starting with an intake that peaks at probably 4500 rpm or less on a 383. Pretty hard to build an engine to make near 500 fwhp at that rpm. Even with porting and runner change it will be difficult to get the performance you desire.

So,,,,Can tpi RUN A 383???? Absolutely yes.
Will you get the performance you desire???? Not likely.

TPI lovers...please save the hate posts It is just my opinion based on my experience.

Al

88-I.R.O.C.

iTrader: (3)

I wouldn't mind making 500 hp. I'll probably run some nos though. That would probably kick it up there.
With some better heads (maybe some from AFR), and intake, different cam, roughly what kind of hp/torque would i be looking at with the 383 and the stealth ram? I know i gotta beef up the bottom end for nos, but i figure since i'm building a motor might as well change what i can while i'm there, and get every little hp i can....

kaptinkafeen

iTrader: (2)

88-Iroc,
If you don't mind, what type of budget are you working with?
-Andrew

88-I.R.O.C.

iTrader: (3)

I don't really want to spend more than 5k on the motor. And i still have to acquire a block...probably won't be too hard though. I plan on building it myself with help from a mechanic friend. I gotta save some for the rest of the car....

Buddy

You have to decide what your going to do with the car. If it will live it's life on the street, AND you LIKE TPI, like you originally stated, TPI IS a good choice. There are so many magazines doing TPI build-ups lately. SuperChevy (that got huge #'s), GMHTP (as stated above), High Performance Pontiac (they just started this latest issue), SuperRod (with a 383 buildup that tested all possibilites - TPI won in torque 500 - none of the others could achive this), there's another mag I have at home, came out couple months ago, like SuperRod. (The engine is suspiciouslly similar to SuperChevy's engine, I think it's the same one.) Anyway, with stock TPI, cam, slight changes & tuning, they added NOS and got over 500 ft-lbs torque.

GMHTP latest issue, there's an F-body shoot-out. A white '90 GTA runs VERY quick with minimal changes (I'dd like to know if the owner is on here, I think he might be )

I have an old mag at home from the 80's, in it **** Guildstrand has a drop-top Vette that his wife easily drives to some crazy 1/4 times. Everyone thinks it's a 383. It's not. Just warmed over 350 TPI. I can get the details of the feature if wanted.

MY point is TPI CAN be made to be run strong. And for cheap. Like I said, there are suddenly mags/builders jumping on the TPI bandwagon build-ups.
They are all stating the same thing "TPI strokers torque rules". People are loving these things. If you have a taste for the look, you CAN easily run with LT/LS cars. Yes modded LS cars will KILL TPI easily, but you'll have more invested in the LS engine. Golen Engines (I think that's the Builder) has a ready-to-run TPI engine, 400+ HP, for just over $4500 or so I think.

88-I.R.O.C.

iTrader: (3)

i do like the tpi for looks, plus it "looks" stock. My car will spend most time on the street and ,hopefully, some at car shows. I do want to build my own engine though....good for learning. I was thinking stealth ram just to save some money over modifing the tpi, but i don't really know how much it would cost to mod the tpi

I would take any links or articles you have about tpi builds though.

88-I.R.O.C.

iTrader: (3)

any other info too.....

1991CamaroRslow

iTrader: (3)

Do a 383 with a decent cam and siamese your base and plenum. LT4 hot cam would work fine. I also get tired of hearing the "go Stealth Ram". I will eventually go stealth ram but by the way this board talks my TPI car should've never broken out of the 14's and even when it does it's "who cares STEALTH RAM GARRRRR". I'm sorry but I'm a college student and an enthusiast. When I think of building a motor I think of maximizing the potential for the minimal cost. You can build a motor that will be night and day better than your old 305 with a good bottom end, a die grinder, and some time invested. You could even keep your old 305 heads and port them out to be amazingly good performers. For me it's worth it to build it yourself and save the cash, to other people with different goals they just want to spend the cash and go fast. I don't see any problem with installing a siamesed base TPI on a 383, if that doesn't do it for you then invest in the stealth ram. I would advise you skip over the larger runners and such as they cost almost as much as the Stealth Ram. Spend your money on the bigger bottom end, and get your heads to flow decent, or buy a good flowing set of heads. Another awesome budget 383 combo would be the Vortec heads matched to the Vortec Stealth Ram but that's really up to you and what your ultimate goal is.

6.LIROC-Z

How many cubic inches are in a 10 lb. nos bottle???

1991CamaroRslow

iTrader: (3)

BTW big blocks will fit in a Camaro

Buddy

Keep your eyes on the classifieds here. There are alot of good parts for decent prices. You may end up deciding which intake to go with by whatever deal you can run into. Just an idea, but it would help keep costs down. Only advice, be patient, the deals are out there, they just may not be right NOW. But keep looking.

Wayne's 383Iroc

The 383 and the TPI = unlimited tire smoke. Build a good bottom end that if you want to later will work with one of the aftermarket intakes. I went with a base, runners and a 58mm TB, my friend does not have the TB and you can not tell that much diffrence. What ever upgrade you do will make you happy. I talk junk to the all the LT, LS, 5.0s and 4.6s guys. If one of them takes me then it will give me an excuse to put my bottle back on the car. Good luck with your combo.

1991CamaroRslow

iTrader: (3)

I did an 8.5 1/8th at 79mph which equated to a 13.5 at 97mph. This was on the high milleage stock long block with a ported stock base, stock runners, siamesed plenum, stock throttle body. The TPI setup isn't all that powerful but it's not a bad system. If you saimese the base you're knocking out some of the lower end torque by shortening the runner length and basically using each pair of runners to feed each cylinder. There was some debate about the number 5 and 7 cylinders going lean but it was disproven. It's a very sneaky way to make a higher revving engine and it only cost you the porting bits and time to siamese the base out. You can make some good numbers with stock TPI equipment if you're willing to mod it out. You can make a rock steady idleing car with a decent sized cam using a 383 bottom end, and you can get the equipment to make this engine bargain priced. Ported stock heads, siamesed base, ZZ4 or LT4 hot cam, sitting on top of a 383 would be a potent combo and lots of fun to drive on the street. Plus if you decide it's not enough for you you can spray it, or convert to the Stealth Ram. Whatever you decide to do good luck with it.

91 355 z28

ok so i have just recently built what you are looking to do. i got a 350 got it bored to 355. i have a comp cam xfi 260 comp circle track roller rockers comp lifters. accel adjustable fuel pressure reg, accel 24 lb/hr injectors. slp intake runners. i have stock center bolt heads. 3.73's in the rear, k&n filters. stock headers upgraded single pipe 3 inch exhaust.. the next item is a chip because it has a stock 305 chip.. the idle is to low for the cam and you can feel there is more power lying dormant between those fenders. the car keeps up with G35's until i run out of gears it spins the tires while rolling up to 30.. im probably going to be taking a ride to the previously mentioned racekrafters for tuning and a chip.. all of the motor work cost me 5000 and i got it built as im in school for what else.. cars right now and have no time. im not gunna lie.. the car is a torque monster probably around 400 ft/lb.. and i went light on upgrades due to this being a daily driver that gets around 500 miles a week.. from personal experiance the downfall of customizing tpi is the computer.. it makes me want to strangle my car.. i HATE COMPUTERS grrrrr.. as u can tell it has been giving me problems.. im not entirely sure at this point that tuning and a chip is what the doctor ordered but its what im going to try and considering these racecrafters guys have some tpi experiance im hoping they can help.. what ever you do dont get a holley fuel pressure reg.. theyre crap.. the whole fuel pressure department has been a complicated one. yesterday while troubleshooting how crappy my car was running i discovered the tps decided to shoot up to 1.5 volts and that my fuel pressure randomly became 68.. hmm.. both of these mysteriously happend the same time i took the smog pump off the car.. all in all i love TPI because of the torque i love my car but it is a headache sometimes as all custom setups are but i hate computers and if givin the chance to go back in time to when i built the motor i would give a second thought to a good ol' carb and vacuum advanced distributor. oh and ive been thinking next time im gunna build an all aftermarket part tpi setup (ie. slp runners, baseplate, some sort of aftermarket engine management like the accel dfi) on a destroked 383 to around 372.. im thinking i might get some devilish lb/ft numbers.. just an idea for you.. as im a lover of no replacement for displacement but can also see the beauty in a 350 small block that can outrun a big block

ps. ive learned the hard way just replace everything when i put the motor in i didnt do starter or wiring or air pump or headers or chip and the basic conclusion new and old parts dont like each other

Air_Adam

TPI + ProCharger will leave the LT1 cars in the dust and more than hold its own with an LS1 car. I've seen it. There a local guy around here that I'm good friends with who's got a ProCharger setup on an otherwise STOCK '85 5.0 TPI. Still has stock cam, stock heads, stock iron exhaust manifolds and exhaust system, stock tune. This car runs low 13s as it is, and makes a rediculous amount of torque in the midrange. Makes good power all the way to 6000rpm too, unlike a NA TPI setup would.

Build a simiar setup onto a 350 or 383 and put a good exhaust system on it and match it with the appropriate cam, and you'd have a real firebreather.

TP355Z

"TPI + ProCharger will leave the LT1 cars in the dust and more than hold its own with an LS1 car"

A 305 with a 300 shot of nitrous can smoke big-block cars...but we're not talking apples and apples anymore are we?

I think something everyone is overlooking here is the fact that the argument isn't against TPI technology. Its against the stock TPI system. Stock, the TPI system plugs a 305 and anything bigger. Build a motor with X horsepower and you can expect less on the dyno - with an increasing loss as your displacement rises. Too - even though a supercharger improves the performance of an otherwise dog-slow motor, it would yield an even greater improvement on an engine with an aftermarket induction system (even if its still TPI).



Also, I read the super-chevy article on the TPI buildup - to say that TPI system even RESEMBLES the stock system on a third-gen is total fallacy.

BlueSmoke

I know this is an old thread but I'm gonna jump in here anyway.

Scoggin Dickey straight up TPI conversion--
SD Vortec manifold
stock runners
vortec heads
L98 Cam/Factory Rockers
Edelbrock 1.7/8 in headers
stock throttle body

dyno's at 305.5hp@4700rpm

Brian Gruben engine mods--
Add edelbrock runners
LT4 Cam/ 1.6 rockers
52mm Throttle Body/24# injectors


Dyno's at 356.7@4900rpm


uhm restrictive or not those are good numbers. http://www.sdparts.com/

five7kid

iTrader: (14)

Already addressed.

That same engine with Performer RPM intake & 750 Holley = 400+ hp. For a lot less money.

89TA383M5

I asked the similiar questions about building up a large ci TPI and my responses were the same. "You could make so much more power with a miniram or Stealthram!" The guy didnt ask about other intakes. Some people have different ideas of TPI. I dont consider a Stealthram a TPI. When I talk about a TPI I refer to a Long Tube Runner setup using the stock upper plenum. Anyone that says you cant go 12's or lower with a TPI setup is incorrect. In answer to the question of how big you can build a TPI is... As big as you want to build a small block. If you go with an aftermarket tall deck block you will have to make an adapter to get the lower intake to work. I wanted to build a stroker 400 like a 434 TPI but didnt have the money and didnt want to go with an aftermarket block to go even bigger to build up to a 482 Small block. I didnt want to have to mess with making the lower intake work with a tall deck block. I asked the question about building a big inch TPI and that was the reponse. "Instead of build a big motor just throw a miniram on you 383." My 413 setup is a low 11 second Torque Monster. I can get the car to hook up pretty well but I rode in a car with a ZZ4 crate motor, TPI, and a ProCharger; and that car would destroy my car.

dhirocz

iTrader: (2)

I will hopefully be answering that question soon. I'm still planning on how I want to build mine. I want to build a large cube TPI motor to make tons of torque on nuts and stuff it into a C4. I untimately want to build a well running 427 TPI, though I might hold back and do a 408ci'er.

Last monstrosity I built was a tuned port LT1. I liked that because the intake always stayed cold thanks to the lack of coolant flowing through the intake. However, I cant support my goal of 427ci with that block, nor will my conversion base will support those cubes. I would have to sleeve a block, change the caps, get some better heads ported and then convert the bolt pattern of the LT1 heads over to sbc style. Lots of cash. Or I could go with a large bore late model bowtie and use it; heads and intake will all bolt together; however, I will have coolant running through it.

Its possible. But if you want TPI to support a larger engine, you need to have a larger wallet. I'm already looking at a custom fitted plenum to a first injections base and runners, fully ported and extrude honed, high velocity heads, and longtubes with at least 18" of 3" pipe coming off the collector into duals. It gets expensive, and one thing I know is with TPI, every place you cut a corner you also cut the power. It's the nature of a tuned intake I guess And even after all that, all I'll be left with is a mostly stock looking TPI motor that is basically dimensionally larger everywhere. All I can hope for is a gain from pure size after assuring the air can get in and out.

For the most part, you put a TPI unit on a engine larger than a 383 and you will have a stump-puller. Nothing more.

One thing I have to interject though. Theres no doubt that LTx intakes and similar short runner style manifolds make good power. More often than not though, the reason is that these are antituned manifolds...they work well with a broad selection of cams and parts that would not work well in a tuned port. Many times, people use parts on a tuned port motor and complain about the performance, but dont think about the intakes' natural tuned frequency and what parts they should use to take advantage of it. You have a charge in the intake tract at a certain RPM called a 'plug' that needs to be timed to work with your camshaft as the valve is opening, with heads and headers that allow free movement without restriction or loss of velocity. The people on here who understand that are the ones making lots of power for a tuned port. Bigger isnt always better. If you cant resist choosing larger parts you are best suited to an antituned manifold like the LT1 or carb as TPI is very sensitive to the parts and modifications that go with. My $.02.

Plan on lots or research and more modest parts selection, with deep pockets, or a different intake selection.