tpi upgraded heads

[band77one]

so ill be starting my 327 tpi build next month, and i don't know much about anything im still learning. the TPI is 1988, and the block is from 1968, any heads will bolt up to the block right? so basically i just need a set that works well with tuned port right ? thanks in advance.

[Pampered-Z]

Man, it's been many years since I played with one of those engines! So this is all from what I remember?

But I think you are correct in that the heads are interchangeable as far as the bolt holes should be the same. If you run older heads (pre 85?) you will need to fix the holes in the intake base where the bolts pass through into the heads because the angles are different. Not a big problem to overcome. I’m not 100% if all the water passages match from an early motor to late model heads either? Likewise you may need to block off the water jackets in the heads that would have passes coolant thru the intake? If the block/head water holes line up, you might be better off finding a set of TPI 350 heads, same bore between the engines. And this way you also don’t run into issues with different exhaust ports making header selection a problem.

I did a 70’s 355 engine in my 84Z and had a few issues to overcome. The early engines had the dipstick on the opposite side from the new engines. I have to “customize” a set of Edelbrock shorties to work. I had to use and aftermarket oil pan, the 70’s pan wouldn’t fit, and the 84 pan didn’t work dir to the dip stick. So you may need to work out a different oil pan/dipstick configuration based on the car the engine is going into? Allot of the fitting (such as the water temp) used different size fittings so I had to get adapters for them.

What are you plans for the engine - Drivability or performance? When you select your heads you will need to look at is the size of the combustion chambers which will affect your compression ratio, and air flow. That combined with a TPI will be needed to determine your cam selection as well. My first thoughts is a 327 could be high compression and you’ll need larger chambers to run on pump gas, or even thicker head gaskets to lower the CR a bit? Also 327s with their short stroke like to be rev’d high, and a TPI likes only moderate RPMs, Since you have less displacement then a 350 you might have some extra air flow, but you’re going to need a cam that works with the TPI set-up.

John

[bubba428]

just out of curiosity, 327s have a reputation for being a high revving motor....why are you putting a top end on it thats infamous for having no top end??? I mean it is an interesting idea. Are you using stock TPI parts or are you going to use upgraded parts, such as runners, plenum, or HSR set up? If you go with stock I would suggest calling Josh at JSPerformance about having it P&P and gasket matched at a minimum.

[band77one]

most likely putting on tpis manifold and slp megaported runners with ported plenum. the motor is not going to be anything super crazy just a nice street motor with a nice amount of power. and its going into an 88 iroc

[band77one]

but im going to guess as long as i get a set of heads that go with the tpi, it will bolt up to the block and with the aftermarket TPI setup everything will run good. now, since its getting heads/cam, and some TPI work, am i going to have to do any computer work? cause im not changing injectors. also, the stock radiator should be fine right?

[bubba428]

stock radiator should be ok, If your going to put all that time in it you probably should upgrade to be safe. it would be best to get a tune, and if you do use 350 injectors. it would help out a bit.

[Fast92RS]

Even with you tpis big mouth manifold and slp runners you will not get the full potential of that 327 with those parts. The upgraded parts will get to peak power around 5000 or so RPM. You should look into the mini ram, super ram or the holley stealt ram. Those intake have what you need to get power to 6500 rpm or more.

[band77one]

http://www.corvetteplenum.com/Mega-porting.htm

that is for the plenum, and the runners will match as well, not to mention the Tb when i have the money for it. so if the stock tpi wall is 5500rpm or 5000rpm. what is the difference now between the super/stealth rams and this mega porting besides this is factory looks.

i just dont want to do all this and then ahve the car fail emissions/run like garbage. so before i spend any money, other then buying the motor. i want to make sure everything will match up and be ok when its all said and done

[Fast92RS]

Originally Posted by band77one

http://www.corvetteplenum.com/Mega-porting.htm

that is for the plenum, and the runners will match as well, not to mention the Tb when i have the money for it. so if the stock tpi wall is 5500rpm or 5000rpm. what is the difference now between the super/stealth rams and this mega porting besides this is factory looks.

i just dont want to do all this and then ahve the car fail emissions/run like garbage. so before i spend any money, other then buying the motor. i want to make sure everything will match up and be ok when its all said and done

The only aftermarket intake that is emissions legal in the super ram. And it can be used with the tpis big mouth intake. This what Im using with afr 195 heads. Those aftermarket intakes basicaly remove the bottle neck the stock tpi unit has and increases its RPM range to increase peak hp and tq. With the right cam and heads these intakes can porduce a lot more power than the stock TPI unit can.

[band77one]

well i sure as **** know i dont wanna spend the money on aluminum heads as it will only be to the track once to see how it does and thats about it lol so im back to square one where i started then

[band77one]

and i just tried lookin for super ram. is there a way to buy the intake alone or do u have to buy the whole system? according to summit its 3500 bucks for the system...

[IROCdan330]

bahh all of those intakes are emissions legal so long as they dont pop the hood and actually know what an EGR looks like.

Oh, and you would need a proper tune so code 32 doesnt pop up...

If you are running a 5.0 computer I would definitely recommend tuning to reach the potential of this combo, and upsizing the injectors so they don't become a restriction point. After all, you are bringing more air into this engine, you need more fuel to match.

Stock radiator is fine, and if you are worried about it running cool a low temp thermostat and tuning will help that as well.

If/when you are ready to tune give Josh @ JS a call and he can give you a quote.

[band77one]

ok well then my injectors are 19lb and 350 injectors are 22lb i beleive, what size would u recommend since im going 327

[bubba428]

what size cam are you going to use and what heads? Whats your compression ratio going to be. It helps to know that to size injectors

[Pampered-Z]

19s are a bit small, you can pick up a used set of 22s or even 24s cheap, and they will be more then eough. I've built a few LT1s and the stock 24s are good to near 400HP before the duty cycles start to get too high. I guess with the right parts you should be in the 325-350 HP range.

Need to check if LT1 stock injectors will work with your TPI, I know the miniram's are different. but if stockers will work I have a set for a 97 LT1 I'll sell you cheap!

[IROCdan330]

At the minimum I would suggest 22lb injectors, but Ford SVO 24 lb are cheap and they work, and like Pampered-Z said, LT1 injectors may work as well.

Engine size isn't related to injector size, power output and fuel demand is...We just put 42# injectors in a 305 car, granted it had a blower, but I'm just making an example. I would rather have plenty than not enough when it comes to injector size.

[bubba428]

Originally Posted by IROCdan330

At the minimum I would suggest 22lb injectors, but Ford SVO 24 lb are cheap and they work, and like Pampered-Z said, LT1 injectors may work as well.

Engine size isn't related to injector size, power output and fuel demand is...We just put 42# injectors in a 305 car, granted it had a blower, but I'm just making an example. I would rather have plenty than not enough when it comes to injector size.

I agree with that 100%. and you can always tune the duty cycle so it will run properly.

[deadtrend1]

I have a set of 22# injects I pulled out of my L98 you can use.

[band77one]

so i saw this car on youtube...has a 305.. i want my car to sound like this,,,if not better.

http://www.youtube.com/watch?v=WIb-8...eature=related

it has an LT4 Hotcam and 113 ported corvette heads from 1991..L98.

how would they work good with a 327 ? + i think im going to splurge and get the stealth ram+52mm throttle body

[Ian]

if you already have fuel injection, you could look into LT1 conversion intakes to keep the costs down and raise your RPM potential.

[Fast92RS]

Originally Posted by Ian

if you already have fuel injection, you could look into LT1 conversion intakes to keep the costs down and raise your RPM potential.

The guy that was doing that has gotten a lot of bad reveiws lately. LT1 inatkes.com. Its seems he has taken peoples money and has not sent then intakes yet. Some one on tgo has been trying to contact him for a year and no responses.

[band77one]

i think im going to go with lt4 hot cam kit, L98 mild ported heads, 52mm throttle body/holley stealth ram. and a set of 24lb injectors. sound good? and obviously gonna get a chip. no point in doing it halfway right ?