51 replies to this topic

[gtrboyy]

There used to be a member on the old forums that had a sta blower & then went turbo,it looks like that car.I think it was from ACT & the owner was mates with Jake Edwards from memory.

[Struggler]

That would be me.

Car was going for a while until I leaned on it one hot day and rattled it, resulting in a split bore. Car was then dismantled and sold off.

This was almost 5 years ago now !!

[Struggler]

Blow thru 450 Holley. 6psi boost. Truck turbo (Holset HX40 from memory) and intercooler. Stock 308 with a cam. You can see the exhaust manifolds etc.

Due to the turbo being a bit of a mismatch to the engine it never realized its true potential.

No other pics, sorry. I think I even lost those that you had.

Let me know if you have any other questions.

[Struggler]

any HP figures dude?

With the STA supercharger on 5.5 psi it made 230 RwKw. Never dynoed it with the turbo.

Engine had cut down flat tops, would of had about 8.8:1

The whole build up was covered on the old, old, old forums, well lost by now.

I have done a bit with another turbo 308 recently, 11.0 at 128mph in an HZ !!!!

[Struggler]

I should have some time tonight to post some more details.

[makka]

this is what I was going to do, before I crashed my car and had to rebuild it, now I am saving and researching again.
one day!

[Struggler]

I should have some time tonight to post some more details.

OK, my basic setup was a near stock 308, machined down flat top pistons, 228/235 @ 050 hyd. cam and standard heads. I used a Redline Maxitork manifold (because it was given to me) and a 450 mech.sec. Holley. As I was on a budget I boost referenced my mech. fuel pump. The Holley had the black plastic floats and I cut the choke housing off. Apart from that it was stock - right down to the jetting. This combo worked really well with about 6 psi of boost. I think I still have a pic of it complete with the STA supercharger, plumbing and intercooler if someone wants to host it. With the STA it was great. From a standing start I could put it in top gear and smoke tyres for as long as you had the nerve to hang on to it. With the turbo you had to wait for it to spool up a bit before it got going, but when it did, hang on !!! Like I said earlier, the turbo was a bit mismatched to my engine, it could have been a lot better.

The HZ was originally built by Jake Edwards. I did a 355 for it about a year ago. Cast crank, SBC blower pistons and the same cam and heads Jake gave the original motor. It uses standard exhaust manifolds, same as my car did and Jakes LX still does. It has about 9.0 comp and has insane torque on boost. It runs a blow thru 600 DP Holley on a Torker intake. The turbo is a single TO4 (I think) and it has a front mount cooler. There have been some problems keeping head gaskets in it, 2 sets of Felpro LP gaskets, it now has Cometics. This engine runs up to about 12 psi boost and is a bit trickier to tune the carb. I drove it to a 11.0 at 128 mph recently at WSID (I think Tiny was there that night). As the mph suggests it is a wild ride, a real top ender with a fair traction problem. It was featured in ZOOM magazine a few years back, issue 62, when it still ran the 326 stroker short.

FWIW I still dont have a real grasp of the higher boost type blow thru's. To run up to about 7 psi the standard DP carbs seem to work OK. After that they seem to need a lot of work to perform correctly. Jake is the real genius of the blow thru deal, he really helped me out when I built my stinker and has since done heaps of turboed V8s, both injected and blow thru. The HZ was one of the first cars he did and most of the set up work on it is his. If you want to build a real turboed screamer then you could do a lot worse than talk to him. He advertises in Street Machine Magazine and is pretty friendly with Bob Kotmel, he is often mentioned in his Stage Write column.

I hope this is enough info for you. If you like I can PM you the number of the owner of the HZ, he doesn't mind discussing the details.

[Struggler]

i think i saw your car at the wakefield 1/8 drags about 5 years ago!
like you stated the turbo rear was too large and was pretty useless over th 1/8 mile but im sure it would have been a serious top end stormer on the 1/4 mile!

Yeah, raced it there a few times, the HZ raced there a lot too, (green metallic four door).

With the STA supercharger I could cross the finish line sideways after hanging the entire 1/8th mile !!!

[LhMusL]

Hey struggler with this 308 turbo you had you pritty much saying that you only really changed the pistons and cam and left the rest of the engine(crank, rods etc) pritty much stock?
Lets say you just put a well matched turbo and a good W/A intercooler on a standard 308, how much boost do you think you could run, and power figures from this. Would want it still to be a daily and reliable so not expecting anything to extreme just realistic. If you go LPG to help with the Compressnio ratio side of things, could a GRA LPG single carb supply enough in a blow through setup??
What would you do on the ignotion side of things??
Just me thinking out loud for a budjet 308 turbo.
Cheers

Edited by LhMusL, 30 October 2006 - 09:28 PM.

[Struggler]

Hey struggler with this 308 turbo you had you pritty much saying that you only really changed the pistons and cam and left the rest of the engine(crank, rods etc) pritty much stock?
Lets say you just put a well matched turbo and a good W/A intercooler on a standard 308, how much boost do you think you could run, and power figures from this. Would want it still to be a daily and reliable so not expecting anything to extreme just realistic. If you go LPG to help with the Compressnio ratio side of things, could a GRA LPG single carb supply enough in a blow through setup??
What would you do on the ignotion side of things??
Just me thinking out loud for a budjet 308 turbo.
Cheers

Yes, engine had stock rods, crank etc.

As a blow thru carb deal you would be fine up to about 9-10 psi, enough to make about 250-260 rwKw. Above this and the carb needs heaps of work and the rods will bend over about 18psi. Stick to 5-6psi and it would live forever on the street.

A single GRA carb will supply enough gas to make over 300 rwKw, but you will have to use two convertors. Use a C/dore HEI.

FYI I am currently assisting in a budget blow thru single turbo carb 308 ATM. It has forged 350 pistons, stock VN rods, stock crank, stock HQ heads, torquer intake, locked C/dore HEI and 650 DP Holley. Uses standard exhaust manifolds and a TO4E. It is all going in a Gemini. The engine is going together now and the owner hopes to have it at the Summernats.

[LhMusL]

Thats awsome dude, all this on 2 bolt mains? 250-260rwkw would be enough for starters/now, as i had 200rwkw before and that was fun but on a na 308. This sounds to good to be true and not to hard to peice together without spending to much.
So 5-6psi on the street would give me say 180-200rwkw? that would be perfect i recon. With a toploader and a 9' i think i could have a lil to much fun with that
All this in the grandpa Lh and its would make a great sleeper.
Thanks mate.

[LhMusL]

Would it be better to start with a 304 so you get the vn heads and rods, plus might be easyer/look better to set up with the GRA carb at the front of the engine instead of on top?
Best option maybe a factory 355????
Don't know what the comp ration is on these though........
Could you get a 308 turbo engineered in victoria, or gulp would you need to go a 253 to get it legal

[Struggler]

Would it be better to start with a 304 so you get the vn heads and rods, plus might be easyer/look better to set up with the GRA carb at the front of the engine instead of on top?
Best option maybe a factory 355????
Don't know what the comp ration is on these though........
Could you get a 308 turbo engineered in victoria, or gulp would you need to go a 253 to get it legal

A 304 would be a fine starting point.

Exhaust manifolds for VN are harder to plumb than HQ.

The factory 304 intake is NOT ideal for forced induction. Due to is design some cylinders take all the boost and others lose out. It will blow H/gaskets and melt pistons.

There is no real benefit in stroking a turbo engine.

304 standard comp. is 8.4:1

Hope this helps.

[LhMusL]

Thanks struggler that helps, so maybe a 304 with a carby manifold so it removes all the fuel injection gear and get better flow to all cyc. Do you keep the computer though for the ignition or can you put on a commo HEI like you said on a 304???
Will prob get custom manfolds if i can anyway so that dosn't really matter, or just spend the extra effort making the vn ones work!
Any idea on legalities though..... or a revvy 253 wouldn't be that bad still plenty of cubes on a FI motor anyway