has anybody done their own tt 305? do you think stock tbi heads with a maf tpi setup would work well? just looking to see what kind of complicated mess this would be to put together

There's no way in hell stock LO3 heads would be able to support that thing. Theres an aftermarket company that just started making aluminum heads for 305s though. Look into that.

i think i'd rather save myself the money and just put a set of 350 heads on there

That might work too. But why spend all that money on a twin turbo setup and then skimp on the rest of the engine?

Willie has a TT305

using a set of rebuilt 350 heads isn't skimping, plenty of people use rebuilt parts on high hp engines. when race engines are built they don't just buy new heads each time.
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willie? any links to pictures?
...nevermind a search is all i needed to do to find pics

A set of L98 heads would be good for twofold reasons, firstly you get increased flow secondly they also decrease the static compression ratio. Then again there's always the notion of leaving it alone and seeing what it does.

Starting the build up of my 87 Formula TPI 5.0 M5 260rwhp and 352ft-lbs torque naturally aspirated.

Current Parts inventory:
2 Garrett 57 trims, with .63 A/Rs
2 38mm TurboSmart wastegates
headers, stainless mount over the valve covers
Air-to-Water intercooler
Turbonetic MF2 fuel controller
Mallory 685 Timing controller
160lb-hr injectors
Stainless exhuast pipes
stainless intake plumbing


will post pictures as I progress, shouldn't take over 10-12 days. (hopefully)
Target HP is: 18-20rwhp per lb of boost, so 15psi should net 550hrwp+/-

Not done yet but progress pics:
Before

After:

Front
ont

Looks good. I like the special effects. What is the black thing in the TB?

Thats a Holley throttlebody air foil...smooth out incoming air..they claim...probably a sap for buying it but in theory it should help.

just curious but why not put a 350-based engine in there and then turbo it later on??? Just curious.

There are plenty of excuses to use a 305!

Smaller bore IE smaller piston surface area has better detonation resistance.

Heads that are marginal on a 350 become decent heads when you take away the 45 cu. in. they have to feed.

The stock TPI will not be the choke in the system anymore the heads will most likely not be able to keep up with the flow. So using a cleaned up stock intake and being able to make power with it.

There really is no debate on cubic inches when it comes to forced induction. It is a personal choice really. If half the people fighting the displacement battle looked at total CFM as compared to CID the debate would cease to exist.

If the little Buick turbo 6 can run 10's all day long with it's small bore, the same principles applied to a small V8 work just as well. Doesn't matter the make of the engine or even the design really! It comes down to moving the air.

yeah
and everyone has turbo'd 350's
i don't want to spend a whole lot for a turbo project so i'll just keep my tbi 305 swap it to tpi and do twin turbos on it.

Why not just boost the 305 TBI?

Im getting ready to finish up on a 335 single turbo setup.
This is the car it came outa..(just the headers/crossover)



This is mocking it up in my car.
http://www.cecoatings.com/images/Car...r/DSC02717.JPG

I dono how many miles ,etc are on this motor. it was in my 85 TA when I bought it.
N/A it ran awesome. (taken down a few turbo tallons,05 GT,and a few head/cam L98's) I figure I'll run it with a few PSI untill I finish the 400sb Im workin on.

OMG! Chris, your car finally has an engine in it!!!!!!!!

lol... ya now it will prob sit like this for a ew years again...lol

Looks good. Any progress is better than no progress and you have a lot of progress in that pic. The great thing about taking your time is that you don't get tired off working on it and burn yourself out.
You were using a Holset HX55 (67mm inducer) / 19 cm turbine correct?

not burnt out just NO time. I sold the HX55 I forget the inducer side but it was a 22cm Turbine side. ( I THINK a 76mm Inducer)

Im gonna run a HX40 on this 335 for now. and Put a PT88 or buy back my HX55 for the 409 motor.

I have found that turbo tuning is much different than NA tuning in the fact that instead of making the heads/cam/intake as efficient as possible, you try to make the turbo setup as efficient as possible and the actual engine isnt as important as it would be on a NA engine.

heh, i have a HX40 too... im still wondering if its going to be way to small for my motor....

from my reading on turbomustang a hx35/hx40 is capable of the 600rwhp range.

how do you go about coming up with the right turbo size? i'm looking into doing my own single turbo 305 now...i've got the cam/heads to make power with the small cubes...a piston change will have the engine completely ready, it's got good everything else in it...cam will love boost (238*/248* @.050 .480"./.500" 114lsa) i need to learn how to read turbo charts and stuff....

!!! DING !!! Turbo Maps will tell you what size turbo you need. Or guesstimate it with a turbo calculator.

but a GT45 would be nice. PT76

Twin 60/63 T3's would be nice also.

i'd rather run a single system honestly...i think they look cooler and i'm conviced they make more reliable power.

anyhow, hey chris, here is a basic overview of what will be the engine...gotta guestimate on size?

3.766" bore, 3.48" stroke
8.76:1 static compression (based on a 12cc dished piston, .015" piston depth, .041" head gasket and 58cc combustion chambers) ~7.5:1 dynamic compression.
113 casting aluminum vette heads with some mild bowl blending...no flow numbers but with 10.2:1 compression the little 305 has been 12.5@106.8 w/ no tuning, so i know they flow decently (same heads on the exact same combo and a 4.060" bore went 12.1@110mph and i had to baby it out of the hole)
238*/248* @ .050 .480"/.500" 114lsa solid lifter cams, 1.5:1 pro-magnums (the engine has all the right parts, i didn't use junk)

i'm curious about a few things:
1. i'll be running a blow through setup with a holley double pumper. i've got a 600 cfm main body, as well as a 650cfm and 750cfm...i've gotten the best results n/a with the 650 body, though im thinking with boost, the 600 will be sufficient.
2. i'm currently running a holley street dominator intake p/n 300-36, it's a dual plane intake with a power band from idle-7200rpms and i've had GREAT resutls with it n/a, though i'm curious if the dual plane will hurt boost. i also want it to fit under the stock hood(yeah, i know that's gotta be hard with a blow through bonnet sitting ontop of a carb) and i've got an old (OLD, lol!) torker I and also the torker II intake manifolds and i wonder if one of those would be better with their open plenums...
3. last thing...know the combo, what size turbo would you recommend? shift points will be right around 6K (that's where i'm shifting now)

Its more "reliable" because boost comes in later and its not quite as vicious of a torque increase.

that and over all cost is a bit less and it's got a bit less fab work involved and it's easier to package it in the car...and again, i like the way it looks better than twins.

ialready bought a tpi setup to swap over and i was gonna do a 350 but i see nothing wrong with my 305 so i thought i'd still put the tpi on there but add a couple of turbos. would it be much harder to do turbo(s) on a tbi engine?

It is good to read that. I think a single is a more cost effective, more simple build, and more simple maintain. My rigs have twins.....but that causes I bought what ever car turbos I could get find that would work decently.
I picked up a single for my next project.

Performance wise, I don't see either setup having an advantage over the other if designed properly.
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If you already have the TPI and plan to use it with the 350ci then build the turbo setup for the TPI. You don't want to have to build charge pipes twice.

You will gain more low RPM torque with the TPI. I think the amount of work would be the same using either the TBI or TPI. I like the looks of the TPI unit better than the TBI, but that is just my personal choice.

something along the lines of this? any reason why the are going for so cheap? demand just that high or something?(keeping production numbers way up)

eBay Motors: GT45 Ball Bearing Turbo - 1000+ HP - JDM (item 130004157859 end time Jul-07-06 12:39:35 PDT)

Why? Because it is a foreign sweat shop knock-off. No where in that ad does it say who manufactures that unit. It is a no-name (read XS Power quality) thing. The specs listed do not make any sense and do not say where they are measured. That is why it is so cheap....to try and get newbies to bite.

Those things don't sell because people tend to know they are low quality knock - offs. Do a "watch" on that turbo and I bet no one buys it.

Ask the seller who the manufactur is. I bet they won't respond.

EDIT: also notice the "there are no returns or refunds" at the bottom of the Ebay ad. You would think a new unit would at least be able for return for the same unit.
Quote from the ad "Large Ø98mm twin scroll compressor & O-Ring sealed housing, Compressor Housing with Loctited clamping fasteners"

Anyone here ever hear of a twin scroll compressor? I didn't thing so. Buyer Beware.

EDIT SOME MORE: notice the Ebayers previous buys. He just bought that turbo, polished it and is now selling it for cheaper than what he paid. Ask him for a close up pic of the Tag on the compressor. Anyway, he knows he got the shaft and is now trying to dump it on someone else.

If you want a single, I have read some good stuff about the Borg Warner S400 in terms of the larger size units. It is reported that they go for less than $550. Look around at Welcome to Turbo Mustangs.com. "Brent" was just talking about them.

well, i saw an XS Power one on there and it wasn't that aweful expensive either (in my opinion) it was like around $750?

Considering a Garrett GT42 is around $2000 new, that would be considered cheap. The twin scroll typically refers to the inlet of the turbine housing. Just means its divided.

eBay Motors: Holset hx40 turbocharger dodge cummins turbo (item 110005316755 end time Jul-12-06 08:21:24 PDT)
would do ya good.

Look for turbo tim on ebay or turbotim.com

yeah i saw that one...holset hx40 huh...i'm gonna throw in a monkey wrench now, why that size? i'd like to throw down a solid 550-600rwhp

Should be a good spooler being smaller then a HX50/55/60 and put you in the 5-600 range form my reading on turbomustang.com

LS1, LT1, SBC, and other GM Turbo Tech

really appreciate the info guys! i'll be spending LOTS Of time reading turbo mustangs!

Exactly.....the Ebay turbo is not a Garrett. It is a low quality knock-off. Yes, twin scroll turbines are extremely common. The twin scroll compressor does not exist (that I know of). I have seen close ups of the TAGs on the Y2004K turbos. They say Y2004K......knock-off junk.



Have fun at the mustangs site. There is all kinds of good info there.....almost endless. There is at least a dozen of people over there that really know turbo stuff and share info about it.

EDIT: Do a search here for user JoBy. He did a stock 305ci Camaro with an HX55 or HX50. I think it was in the mid-13s with blowing the tires off it. He posted some videos. It seemed to build boost pretty quickly also.

uuuhuuuu !!!! the DIY junk yard build section is good also. Actually the complete site has lots of good info..

hey chris, i posted a topic over there in the GM section...could ya check it out?

so where would one look for single tubo headers at and what kind of $ would I be looking at?
Thanks.

Do yourself a favor and don't skimp on the turbo. You'll bankrupt yourself when you start sending pieces of metal through your intake as well as bearings from using an inferior product.

IMHO here's my l;ist of people I buy from.

Turbonetics- been in it for years pricy, but you get what you pay for!

Limit engineering(john Craig)- Really knows his stuff will build or rebuild your turbo so you'll never have a worry in the world.

Precision engineering- Again been there a long time, they make great products. They have a big selection of products.


Not spending the money now will make you spend 3X later on. Compressor wheels walk shaving a little metal sending through your engine. Excessive bearing wear sending junk into your oiling system will destroy your mains....

JMO!

yep, that's what i'm reading so far! i'll be running either a Master Power or a Holset, which are good turbos, or if i come by the money, a turbonetics or garret

my buddy makes 450/550 on a stock ls1 with a tsp cam and a Master power t-70, and he bought it brand new for 550 bucks, ive heard/seen nothing but good stuff about MP turbos and they dont break the bank either, anyways..