[bonuts]

Now that race season is nearing a end (finally) I wil be able to attack one of my projects. I plan on doing my '67 nova this fall. I want something different, and I'm planning on doing a inline 6 that would have come with my car. I know they can make OK power, but I want a bit more than OK.

I've found very limited info on this, some aftermarket parts, but not all that I want. I plan on building a turbo (possibly twin turbo) by using the small Mitsu ones that came on the 4 cylinder Mopars. They're cheap and, and I don't plan on going with high boost. I've done some research on what parts to use for a turbo charged mill, but would like any info you all have. I'm new to the Turbo scene, mostly building small blocks for all my cars, but now I want something not everbody has. Seeing that nearly all 6 cylinder Novas are now fitted with small blocks, or even big blocks.

Any info on this would be great, I'm sure its been done just can't find anything to get me started. Which 6 to use 250, or ???? is my turbo of choice going to work?

I'm probably not going to be talked out of this, but I will need help doing it. Been cursed out by everybody whos heard of the plan so far, don't expect any difference here, so go ahead try and talk me out of it.... Might be the best help yet!


bonuts

[OneMoreTime]

Try inliners.org as those guys do some interesting stuff with the inlines..Myslef I think I may like the 292 a bit better..it is taller but shoudl fit ok..

As far as the turbo I think going with a single turbo and try and find one that was made for the size of engine you are using..the tubes to hokk it up with would need to be stainless I would think and having an intercooler would be good..

With a turbo I believe a mild cam and about a 9-1 compression would be fine as long as the boost is not too high..Should go like stink in a lite Nova..

Sam

[35chev/302gmc]

Go with the "292"
check out clifford performance 6=8
Tom Lagtons "stovebolt"
Both those companys offer performance 6cly parts

[ap72]

I would go with the Mitsu turbo you're talking about and about 8:1 compression. THe smaller turbo is going to choke the enigne at 6,000 rpm, but an inline 6 with a factory crank shouldn't go that high anyway. THe smaller turbo will spool faster and help the low end torque, whcih is where inlines shine and what really counts on the street anyway. running them at the stock setting will allow pump gas as long as you make sure to clean up the combustion chamber a bit (which is assumed on a performance application). High quality cast pistons will work for this setup as well, and if possible I prefer cast for the street. You're biggest obstacle will be your fuel delivery- multiport EFI would be best, but will require custom work. It helps immensly on turbo cars, but if you can't afford to even go with something like Megasquirt then a blowthrough carb can work, but you'll want to keep the boost fairly low and intercooling is a must.

[matt167]

a 250 should have a T3 turbo at least. the small turbo your talking about is too small and will cause overboost where the wastegate can't keep up and boost's past where it should. for boost you could go up to whatever your compression can handle with a blow through carb, intercooling is reccomended for anything over 10 PSI. you have to boost refrence the fuel pump by running a brake line epoxied in the fuel pump vent, to a place that will see boost, this increases the fuel preassure accordingly.

[ap72]

you can help preven overboost by porting the wastegate- adn that helps a lot on that partiular turbo. boost creep will still happen in the upper rpms, but from my understanding this is a street car and having full boost at 1500 rpm is a HUGE advantage on the street where you rarely see above 3500 rpm.

A t3 would do well on a 250 for racing, but I think (just my OPINION) that low end boost is more of a concern than high rpm boost creep, and even if it becomes a concern an external wastegate solves that problem.

[matt167]

Originally Posted by ap72

you can help preven overboost by porting the wastegate- adn that helps a lot on that partiular turbo. boost creep will still happen in the upper rpms, but from my understanding this is a street car and having full boost at 1500 rpm is a HUGE advantage on the street where you rarely see above 3500 rpm.

A t3 would do well on a 250 for racing, but I think (just my OPINION) that low end boost is more of a concern than high rpm boost creep, and even if it becomes a concern an external wastegate solves that problem.

a T3 is not a big turbo, 3.8 GN's used them and 2.3 Turbo's used them. you could see full boost at 1,500 with a T3, get the right compressor wheel sizes and housing sizes. .60/.82 are common but you can get smaller housings. if you run a boost controller and cut the preassure signal to the wastegate you will get full boost at a lot lower of a RPM. it's all in how there run. a T4 would be good above 2,500 or so. a T3/T4 Hybrid would be good because you get the compression a T4 has but the quick spool of a T3 due to the smaller exhaust housing.

[bonuts]

Wow, I guess I need to do more homework. The car will be a street car, grocery getter if you will, but I want it to make big power.

Some stuff I didn't understand, I originally wanted to go carbuerated, can I do this? Whats a "blow through carb"? I've never really dealt with computer controlled gear, but I'll learn if I have to. I plan on running low boost, I think they ran 6-8 psi originally in the POS 4 cyl mopars.

Is a twin turbo set-up out of the question? I wanted to do this just cause I think it would be cool to see, obviously if it can't be done by a amateur I'll avoid it, but really with the cost of the parts I have so far I could care less if the motor grenades. Once I told people of the plan I had everybody and their dog offering me their inline 6's.

I have 60 over cast pistons, slight dish, but not sure what the compression ratio will be when all is said and done. Told they will make 8-8.5, too high? The bottom end will remain stock, because from what I have found they are strong to begin with.

I'll keep reading if tyou keep answering. Thanks for the help, over!


bonuts

[matt167]

a twin turbo is possible, but you won't bennifit from the extra turbo. a blow through carb is a carb modifyed to be able to take boost and still work, they drill out ports and sometimes jets.

[ap72]

big power and stock do not go hand in hand, and the "POS mopars" were damn near impossible to kill (high nickel block, all forged internals)

two mitsu turbos can be made to work, and can support around 400 hp- which is almost more than you want on a stock inline 6 crank.

Basically it sounds like you're trying to get by for cheap- in which case, I would go twin mitso turbos, twin J-yard intercoolers (the best you can find) and megasquirt on a homemade intake. Yea that'll cost a little more than a blowthrough carb setup, but if you want to reliabley make big power you really need the tuneability of efi.

[matt167]

my friend figured out how to kill 1 of those 2.2 4cyl turbo engines, was in a '89 New Yorker, ran the crap out of it until it developed a bad rod knock, he gave it to the local mechanic after not wanting to pay the tow bill to the scrap yard, gave it to his son and he was going to give me the turbo but if I took the turbo, I had to take the car, I arleady had my Buick 3.8 T3 super 60 that was given to me, so it wasn't worth it, granite I look back on it now, I could have cut the roof out of it for spare steel for repair panals, and then got $ for the hulk at the crushers.

[1969NovaSS]

Running a single turbo is more efficiant then runnig twins unless you have space isuses which you shouldnt. You can run the mitsu trbo but use a EBC instead of a MBC. MBC's are like a meterd vaccum leak and can creep when you or overbossting. Also you can run an external wastegate That can keep up the your flow and that will also get rid of the boost creep. Its a lot simpler for a novice to weld on an adapter then to port out a turbo.

[bonuts]

Not really trying to build a cheap engine, I've built a ton of race SBC's for my stock cars, and other cars I own , or owned. I'll spend the money if its needed, but from what I understand the stock bottom end will hold up well. I have no problem buying a good intercooler, or a turbo for that matter. Just because I know where there a couple turbos from the 2.2 mopars kicking around. I was thinking carbeurated because I can work on them, as soon as it goes computer, I'm gonna have to do some learning.

I say POS mopars because in high school there were 3 of the turbo Daytonas, and they never stopped working on them, maybe the motors were OK, but the rest (tranny) were garbage. I do remember them rebuilding them engines too.

I want to see what one of these 6's will produce, and if it turns out its not enough well... SBC it is.


bonuts

[halfprice5]

Hot Rod mag had an artical on I6's Clifford was a contributor. They have a 12 port AL head for the 250/292 six. NA power was very good, close to 300hp with lots of torque.

I would suggest a T3/4 hybred or a Holset from a Dodge diesel, less then 7lb don't bother with an intercooler, or use a small one. If you want more boost when you need it use NOS.

EFI is pretty cheap using the MegaSquirt and you can do ignition with it too. The long runners would cause mixture distrabution problems in a I6. I lean cylinder or 2 can turn all your hard work into junk very quickly. With EFI its not a problem.


Bob

[strummin67]

Hello Bonuts.
Here's a link to a guy who races a '63 Nova with a 250. Check out his drag videos.
http://www.t6racing.org/

Strummin