My 2L six race engine let go after nearly 3 years, or 22 race and dyno sessions Options

[john rogers]

After getting tired of hot rodded fours that would make a lot (200+ HP) only wanting to last a couple of race weekends we put a 2L six in my race car. This was done in Oct 2003, a while ago. Since then I added up the race weekends and counting 2 dyno sessions of about an hour or so each that came to 22 racing sessions. The hardest were by far the ones in Mexico as I drove harder on rougher circuits that the ones here, but alas at the CA Speedway several weeks a go it got a very bad vibration at about 7200 RPM so I parked it. When the engine was opened, we found a rod had broken, probably after the bearing failed and actually swelled the case over the rod area but did not cause a case rupture! The case looked like it had been repaired a long time ago as it was not the original casting in that area, but I bought the running engine out of a race car when it was newly rebuilt so I put all the time on it.
As for cost, I paid $6500 for the complete engine with Weber 40IDS like new, 906 cams(reground) , 2.7L ported heads, flywheel, clutch, alt, sheetmeatsl, etc. So the estimated cost of the long block was about $3000 which turns out to be a pretty good deal over the lift of the engine. Now trying to figure if I should stay at 2L or go to 2.5L or 2.7L, since more power is always nice!?
We did pretty good preventative maintenance such as opening the oil filter after every weekend and after the last sesion before this no bearing material found in the filter or in the pump screen so I guess it was just time?

[J P Stein]

I've got 5 years of autocrossing on my 2.7L.
The duty it sees is not nearly as severe as yours has seen, but we ain't doing too
bad (IMG:style_emoticons/default/biggrin.gif)

I don't have any recommendations for your new (improved) motor....but I always liked the 2.5L short stroke motor for racin'. (IMG:style_emoticons/default/biggrin.gif)

[brant]

John,

thats great..
not that the motor is acting up, but great that you got so many hours from it.

hey.. how do you put 2.7 heads onto a 2.0?
I'm confused?

brant

[Cap'n Krusty]

John,

thats great..
not that the motor is acting up, but great that you got so many hours from it.

hey.. how do you put 2.7 heads onto a 2.0?
I'm confused?

brant

THat would be my question, too. You can't put them on a 2.2 (BT, Tried That), how can you put'em on a 2.0? The Cap'n

[Brad Roberts]

2.5 Short stroke ALL the way John!!

Sorry to hear about your loss.


B

[john rogers]

I have no idea either, I just drive 'um. I think the heads were welded/machined and used 2.2 barrels and a de-stroked crank although the case has not been split yet. The part # on the head is what gave that away. We had to measure the cams to be sure they were 906 duration and lift as they were regrounds since the factory only made something like 50 real 906 cam sets and they were. I am laeaning towards a full 2.7 engine which will be handy for more torque than the 2L was and not have to run it as hard to get by those dammed 356s I race with.

[J P Stein]

If you're thinkin' 2.7, you may as well go 2.8.
New P/Cs either way, eh.....

[Brad Roberts]

Buy a 3.6 and de-stroke it to 3.2! This is the hot ticket right now. GE100 cams and NO porting on the heads. Just do a valve job and plan on a reliable 355hp.


B

[Cap'n Krusty]

I have no idea either, I just drive 'um. I think the heads were welded/machined and used 2.2 barrels and a de-stroked crank although the case has not been split yet. The part # on the head is what gave that away. We had to measure the cams to be sure they were 906 duration and lift as they were regrounds since the factory only made something like 50 real 906 cam sets and they were. I am laeaning towards a full 2.7 engine which will be handy for more torque than the 2L was and not have to run it as hard to get by those dammed 356s I race with.

Seems like a lot of effort to end up with a big valve 2 litre, what with having to basically remanufacture the heads. I probably would have gone with 2.0 S heads, but I don't do race motors anymore, so I may be behind the curve. The Cap'n

[Brad Roberts]

I think it depends on which heads and or block they started with. It all comes down to the stud spacing? Correct?

I went through this with the early 76 930 turbo 3.0 engine case. People build wild ass short stroke engines starting with that case.


B

[Thorshammer]

I agree with Brad. The 2.5 66x90 motor is my favorite of all, but don't "overhead" the engine. And (all Porschephiles cringe now) try something besides a 906 cam. Even regrinds are really not the best. People put them in because thats all they know. You might want to look at Integral Cams (Steve Gruenwald) he grinds the GE series cams, but also does other grinds that will produce better and more useable HP than the 906 cam. I have tested several 906 and 906 variants and have never found that particular grind well suited. A really nice 2.5 with (46x40) small port heads (high velocity) and the proper manifolds, coupled with the right cam should yield excellent hp, with very good power "under the curve".


Erik Madsen

[Brad Roberts]

The man above has done his homework! Listen carefully to him. I have a funny feeling I know who is building Johns engine (Mark Kinniger) and he is old school. He probably wont work with newer technology unless we offer him sound advice.

John, if it is Mark, I'll chat with him this weekend about some idea's!! Unless you dont want me too.


B

[TimT]

The 2.5 is a great motor, but if you race in PCA it puts you in the middle of the GT4 displacement bracket ( GT4 is over 2.2L to 2.808L). Im not sure how other orgs bracket classes by engine displacement.

I agree with losing the 906 cam, its to peaky with a narrow powerband. a GE60 cam would be sweet.

[john rogers]

Thanks for the advice guys. The engine was built by a race shop in Riverside CA and was used briefly in another car but was deemed to be "to small". Black Forest has the 2.7 which is a full long block with "S" cam so it would be a tad less radical than what I was using but be able to keep up pretty well with the other VARA and HSR West Porsche class cars. It has a couple of thousand street miles and then has sat for a bit. It would bump me out of the 2L challange but that is okay as I have got to the point in my life where winning is not the big thing it used to be. In the Mexican street races the extra grunt would be nice to have as they have those 180 degree sloooow corners.

[Brad Roberts]

Oh cool!!

You already have a engine lined up! Excellent. Slap it in and have fun again (IMG:style_emoticons/default/smile.gif)


B

[brant]

John,

wow.. the old motor has 2.7 heads for certain?
thats crazy..

I would almost bet a beer that if you tear open the old motor its not really a 2.0 given the heads.

thats insane..
I wonder if they sold it to you as a 2.0 and its really a 2.4 or something.

not trying to insult you but it just doesn't add up.
have them measure it out when they tear it down.
if its got 2.2 barrels (also used on the 2.4) then how would they de-stroke it with a 2.0 crank?

crazy

brant

[john rogers]

The size could be something else and when the engine comes apart we'll know. A couple of people told me it was a 2.2L and others said a 2L so I don't know. It was pretty peppy though out running those Corvettes in Mexico and all!

[drew365]

John, my engine is a 2.7, twin plug with S cams. When I was younger (last year) and learning to shift properly I over revved the engine several times by miss shifting. The engine never missed a beat. I no longer speed shift, but I'm still glad I have the twin plug, I think it's a good choice for a track car.

[brant]

The size could be something else and when the engine comes apart we'll know. A couple of people told me it was a 2.2L and others said a 2L so I don't know. It was pretty peppy though out running those Corvettes in Mexico and all!

do let us know.
didn't you dyno her once upon a time and get something like 190 at sea level?

brant

[guiltless]

Buy a 3.6 and de-stroke it to 3.2! This is the hot ticket right now. GE100 cams and NO porting on the heads. Just do a valve job and plan on a reliable 355hp.


B

Reeeeeeeeeeeeeeellllllllyy. Where can I find info about this?