I have noticed that when I tell people after I swap my 305 for the 350 im building. That I will still be using TPI alot of them are against it. I think
for a 300 hp street motor it should be no prob, well it might have a little more than 300 . Your thoughts

 

Thats because most people are ignorant and don't realize TPI is far more superior than a damn carb.

 

For the record, I'm a TPI lover. I'm running a TPI right now, and I think it's the sexiest intake ever to grace a small block.

That being said, .....it ain't the best. For all the reading I've done over the years, I can't think of a performance situation that was actually BETTER with a TPI. Sure it makes better low end than most, but if you think of your entire driveline, trans, rear, etc. etc. you can usually make up for a weaker lower end, and go with more flow up top. That thinking typically does NOT work the other way around.

I, like many other here have a thing for making our TPIs perform. We like the fact that it has some heritage. We like that its an OE design, even if it has aftermarket runners etc. We like the fact that it looks pretty much stock when you open the hood (sometimes). That being said, if I didn't already have a TPI, I wouldn't go buy one!

I think it'll work for what you want, and don't get discouraged with what other people have to say. But don't forget to listen to what those people have to say either. It's very possible that you'll want to chose another intake system. Maybe a StealthRam?? Modded Lt1???

Good Luck!

 

I'm just gonna sit back and watch this one unfold!

 

Carbs are great if you're on a low budget and have no money to spend on fuel injection but I'll tell you they're sloppy and inefficient for metering of the fuel/air mixture.. Top fuel dragsters don't even use a damn carb, they're using some massive injectors.

 

Go with a different intake manifold IMO so you can get more hp and better top mph. Go with something like a miniram or stealth ram to get better overall hp.

 

 

Pure enjoyment I love to hear good replies. I certantly like the looks of TPI and since I already have it why not use it.

Here are my current build specs.
350 4 bolt main block 69-80(casting#3970010) .030. I will be re-using the 305(58cc) heads, with new springs valves and studs. Cast crank, TRW flat topped pistons, Crane Cam (powermax 2030) @.050 Lift int 107 exh 117, Duration int 214 exh 220. Stock TPI equipment.

Its gonna have high compression but what the hell if its really bad ill get some bigger cc heads.

 

Are TBI motors cheaper to make hp on?

 

hell yes if you want to make boat loads of power for cheap TBI is the way to go. i even heard of one TBI engine beating a carb car

 

lol, Yes...... I think what Ede means is you can make boat loads of power for cheap with tbi If the previous owner of the car had already replaced the heads, cam and factory tbi.

 

BWHAHAHAA..

Each has its own merit..lol

BTW I love you ede

 

I even swapped out the SFI on my Buick and retrofitted a TBI unit on there. Now I have TBI AND a turbo. Best of both worlds.

 

That's just plain ignorance right there.

You guys all have it backwards, the real path to power is this...

 

For me the question isnt which type of injection, its what type of intake manifolds are supported. Would an HSR provide more streetable power than a tbi performer?

 

That's funny, how you put it so bluntly.

I agree- TPI is superior to the carb.

I also think the LS1 is superior to the TPI. Maybe that will change- the VORTEC heads are demonstrative of the power that still lies in the GEN I blocks.

Personally, I think TPI has more visual impact than the plastic LS series. I've owned both too. I just love TPI era third gen f-bodies- even TPI third gen Vettes (had one of those too)!

 

It really depends on your goals. Meaning. What the the car is going to be used for? But really the stock TPI is capable of power levels above 300 hp.

As long you are happy, who cares!!!

 

8 injectors + the cold start duct taped together and stuffed down a 4 barrel carb would be the best of both worlds. Use the shiny duct tape, it's better than that fabric stuff.

 

Yea there's that......... and there's always crossfire injection.

 

Hey Zbra, pass the popcorn!!

 

vortec heads are weak sauce! LOL out of the box they arent very impressive... they need work, and by the time you do that, you could have some trickflow 195's that will outflow them on both sides int/exh and be lighter in wieght.....

but i wouldnt mind having a fastburn setup....

 

I have buit a 383 with the protopline vortec heads, and I am using a TPI setup. I am using a ported SDPC base, SLP ported runners and, a stock ported plenum. The runners and plenum are siamesed and everything is ported about as large as it can go without having to glue it back together. I made 312.5Hp and 367.1 torque. Thats respectable, but for the time I spent grinding and picking silver boogers, I think I could have alot more for alot less work if I would f just broke down and looked for a different intake.

 

Are you sure about that? Look how much faster 305 TPI's run than 305 TBI's.

 

Facetious:
Main Entry: fa·ce·tious
Pronunciation: f&-'sE-sh&s
Function: adjective
Etymology: Middle French facetieux, from facetie jest, from Latin facetia
1 : joking or jesting often inappropriately : WAGGISH <just being facetious>
2 : meant to be humorous or funny : not serious <a facetious remark>

 

If you are going to use it only for the street than go ahead and do it. You will see better mileage than with a carb. For street only traffic driving the TPI is awesome, how many times do you really get a chance to get up to 5,000 RPM in traffic? Go with TPI. It is the best intake for low end traffic driving and mileage.

By the way, does anyone remember the last time someone tried to argue with Red Devil? I would not do it!

 

DAVECS1, What kind of cam, headers and TB did you have in that 383? The SDPC combo they had in their 92 Z28 camaro was the LT4 hot cam, 1 7/8 headers, i think Edelbrock siamesed runners and a 58mm TB and they came up with 356 Hp, and that was with an L98 350.

 

I am running Comp Cams Xtreme Energy Marine cam 12-236-3. I am plannin on adding a Supercharger some day. I personally think the LT4 Hot cam has to much overlap. I agree my power numbers could be better. I have some tuning left to do. When I was on the dyno, it seemed everytime I added fuel where it needed to be it would go rich an lose power. I attribute that to the intake. I am running a 52MM throttle body and SLP 1 3/4 headers no emmisions.

I have read about that combo and that is why I decided to build mine, but I believe that 356 number did not come from the chassis dyno. I also believe the runners where not simesed. I think my motor at the flywheel would have some more grunt than the SDPC combo, but probably not the numbers a 383 should be spitting out.

I was simply stating for the time and effort that i put into trying to make TPI viable. I could of had alot more tuning done on an easier cheaper intake, and my numbers would probably be better.

 

Dave, What transmission are you using? Allen

 

I am using a 700R4, that I had built up by local trans shop in town. I am not extremely happy with it. I have been tuning the governer and I can get it to down shift and stay in the right gear the way I would like. The trans wants to operate in the 1000-3000. rand and my powerband doesn't really start until 2500. Don't get me wrong it works well below that, but the reall kick in the pants starts there. Aslo I am running a vigilante 2500 stall, with a soft hit, but it feel like it is stalling at 1800, and that causes some issues at idle. I suppose tuning could probably smooth that out a little. I have been contemplating a tremec, and just forgetting this tune the trans crap.

 

Im not at all saying your combo is bad (especially w/a 383) I was Just curious what Kind Of Combo it was. Also that power you made was at the rear wheels? or at the fly wheel? Sorry if I offended you at all!

Thanks,

 

I was trying to figure your power at the flywheel that is why I asked what transmission you are using. Allen

 

No offense was taken at all! I thought I would just throw out my experiences with the TPI since I have tried several combos with varying results. I am pretty easy going it would take alot more than calling my combo crap to get me going. If there is one thing I have learned playing with cars all these years.... somebody will always be faster, better, and louder.

Yes those numbers were at the rear wheels. I dynoed the car at T&J's dyno shop in Peoria, IL. I spent about an hour and a half and made 4 pulls and six chips. I burn my own chips and the dyno time costed about 150 dollars. I have not had a chance to scan the graphs yet so for now you can take me at my word or not. I think the dyno was a dynojet.

As far as calculating driveline losses, I am running a 700R4 wit a stock aluminum GTA drive shaft and the stock 10 bolt with the stock 3.23 gears. I do not mind the questions that is why we are here so each of us does not have to reinvent the wheel each time we work on our cars.

 

Ok, cool, those Numbers are pretty good . I didnt know if those were rwhp or at the fly. The SDPC combo's rwhp is 285 and 356 at the fly, so your power at the fly must be around 360 or 370! Im trying to get around 340 at the fly. Ive done almost the samething as the SDPC combo but i dont have an LT4 hot cam or 1 7/8 Headers or a bigger TB. Ive heard that the bigger TB doesnt really make that much difference.

Thanks,

 

I hate those silver boogers! Almost as bad as black ones!

 

Warbird, are your hp figures in your sig, an estimate or what you actually got on a dyno or at the track. Do not take me wrong I am not calling foul or anything, I would like to compare the differences in or combos and I would like mine to be closer to yours.

 

well if i put a 350 long block engine that produces 305 hp in my car with a stock TPI intake manifold on top it that came out of a 350 tpi, the only thing doing to it is headers and exhaust, is it possible to pull off 350hp out of my engine, i want to know, i am not sure

 

TPI makes a much better street car than a carb IMO. However the hp it makes is relatively weak, but the torque is HUGE.

Id give up some of my torque in a heartbeat to be able to rev to 6000rpm.

 

Not to rag on you SurfnSun, but a single turbo, much less two, negates any drawbacks whatsoever TPI may have. I would be led to believe your car would gain very little from a different intake. The TPI suffers from its long runner lengths when the pistons are trying to suck that air down the long passage ways. With a turbo you do not have this problem because you are stuffing it in. You jest need a way to get all the crammed air out faster with a big exhaust. I drove the SledgeHammer C4 at Mid America Corvette, in Effingham Illinois, during the Porsche show they had a couple years back. It is rated at almost 500 ponies and it feels like they are all there. That car has almost a stock TPI with 1 3/4 headers and 3" exhaust.

 

Not to rag back Dave, but you obviously didn't drive the Sledgehammer. It has 900hp and does not use a stock TPI. Callaway custom built a manifold for the car using a cutdown dual tunnel ram carb manifold with a sealed up TPI plenum on top. Hell, my car has over 500 crank hp now.

Now back to the facts at hand, my dyno sheets will still show even with turbos, the choking effect of the TPI stands. I thought the same thing as you before I bought the car, but its not the case. The car is still chocked down above 4500rpm. And thats with a big exhaust...power effects true dual 2.75, no cats.

 

Boost is just anumber based on the restriction present in the intake system.

Think about that for a minute.

If u run 18psi on a car and say u had the heads done by Champion and a complete rewelded intake+porting and now that same 18psi before is now 10 or 12 psi. The less restrictive intake actually lowered the boost because the car now is working 33% less to move the same amount of air thru the engine that previously required 18psi to do the same job.

The turbo will always help any car, but the same design flaws inherent from them are not automatically fixed by pushing boost thru it. It will help as is obvious by SurfnSun's chart :-)

SurfnSun:

What are the mods to that Peterbilt(lol) engine in your vette?

Was it upgraded originally or have you upgraded it since?(assuming you upgraded it since its an early car, lower hp)

Buy it new or used?(if used do u mind sharing $$) Curious because if I ever find one for sale I wouldnt mind getting one.

later
Jeremy

 

Well it may not of been the sledge hammer, but I drove a twin turbo C4. I thought it was the Sledge Hammer. I fuel injected an 89 Countach for a friend of mine, that was invited to the Mid America Corvette show. The owner of Mid America Corvette, Let us store the Lambo with his private collection of vettes located right by the Mid America Corvette Museum. He had a number of vettes. Two of them were C4 world challenge cars and the one I drove was a twin turbo. I remember popping the hood. It looked like the oil would be hard to change because it had either a boost tube or intercooler tube running over the oil fill. It also had what looked like casted aluminum stock runners, instead of the tubine type that came on F-bodies.

I cannot argue with the Graph! That is pretty cool to see. I just assumed the turbo would compensate. As you can see before I have been struggling with idea of keeping the TPI, on my engine.

I am sorry for making an A** of myself, but if you do not mind me asking what heads are you running? Sometimes it is hard to find guys on this board that are on the level.

 

Jeremy, youre pretty much right on all counts except for the part about mods actually lowering boost. In a supercharger application youre absolutely correct, boost is based on the size of the pulley. However in a turbo application the turbo will "fill" any available area until it reaches "x" psi when the wastegate opens. For example when I went to the big exhaust and big wonderbar the boost actually went up, b/c the turbos were spinning so much easier...it required wastegate adjustment.

As far as my motor goes, Callaway built the car with a splayed 4bolt caps, forged crank, rods, pistons. Believe it or not....the cam, heads, intake are as stock as the day Chevy put them in the motor. The put stronger valve springs on the 113s and put them on the car.

The 87s were actually the weaker cars...rated at 345hp/465tq at the crank from Callaway. In 88 they went a considerably larger turbo and power went to 382/565.

There is a guy on our Callaway forum that just dynoed 650rwhp/730rwtq thru the stock TPI!!!! Hes running a super built motor and 22psi...which makes my 12.5 a bitch.

Anyway, I came over here looking for one of those TPI to Carb elbows that I wanted to put on the car(which is for sale I might add). But they seem to be discontinued, so that is that.

 

double post

 

Some people hate carbs, and love TPI....

Others hate TPI, and love carbs....


Here something for both to enjoy...

 

Have fun guys...

 

I really hope that isn't yours. That has to be one of the most pointless things Ive ever seen on a car.

 

Necessity is the mother of invention, and that has to be the reason for that... Thing!

Inventive to say the least.

 

The fuel will do nothing but puddle up in the plenum. Stupid idea. That was fo sale on ebay a while back.

 

Hell no. I just keep the picture so I can laugh at it from time to time.