I don't now if anyone has been seriously following my project since I don't post about it too often but here are some background posts.

https://www.thirdgen.org/techbb2/sho...hreadid=200980

https://www.thirdgen.org/techbb2/sho...10#post1585010

Anyway, things are going pretty well with it except for an oil leak that has eluded me for all of the 110 miles of the drive train's life (I think it's oil dye time today). Messing with the Holley Commander 950 engine management system is a BLAST in my opinion. The tune is fairly close but still needs some tweaking to get the most out of it. It makes some pretty good power although I have the rev limiter set at 4500 to keep me from getting over zealous by mistake and I haven't had it to WOT yet. One thing that is killing this setup though is the 2.73's in the back. Imagine this, 2.73 rear gear, 2.66 1st gear, 1.78 2nd gear, with a 234/242 duration cam and a tunnel ram intake, yeah ugly I know, but I'll be going with 3.73's or 4.10's in the near future. Hopefully I'll have some dyno numbers in the near future.


Tom

 

Thanks guys

 

Thanks for the update. What did you end up doing to mitigate the throttle body clearence problem with the hood?

 

 

That's a Harwood bolt on 3inch cowl and it BARELY fits.

 

Anxious to see hod the hood looks!

 

Looks great. Do you have plans to paint it green to match the car?

 

Dude, gotta couple questions for ya. First of all, engine looks great and I have been following your posts. Could you refresh my memory as to what heads you are using? And please throw the specs of your cam at me. I am wanting to do a 383 buildup with Pro Topline heads and I am trying to figure out what cam will work with the HSR and a 383. Any advice and/or updates would be awesome. Just let me know....especially dyno sheets! Have fun tuning away...also where is your oil leak coming from?

 

Well the heads are 220cc 72cc chamber aluminum heads and the cam is 234/242 @ .050, .539/558 112lsa. And I still am not sure where the oil is coming from yet. It's coming from somewhere near the rear passenger side of the head and I'm 99% positive that it's not that VC colver leaking so I'm kinda stumped.

Tom

 

How much oil do you see? If it's a large quantity you should check the rear of the engine for leaks from the oil galley plugs. The oil could be running from the rear of the block down to the head.

 

Check the 2 bolt holes on the front of the block, down low, where the smog pump bolts. If you look into the upper one of those 2 holes, you will see the mechanical fuel pump rod, or its passage if there's not a rod in there; in other words, you're looking right directly into the crankcase.

This is probably the #1 most common new-motor mystery oil leak. It will not leak (not much at least) at idle, but will absolutely spew violently at higher RPMs, and will drench the entire pass side of the lower part of the engine bay with oil.

Put a short bolt in that hole with some silicone onthe threads.

 

Well it's not a big leak at all, it's pretty small but enough to really **** me off since I built all of it with the exception of the short block and pretty much everything is brand new. I put some engine oil dye in it a last night and ran the motor for a little while, then I pulled the y-pipe and starter, and from the best I can tell is....it LOOKS like it is coming from the head/block deck right above the the number 8 cylinder. Oil can't leak from the head gasket right? Especially without burning oil? I'm pretty sure it's not coming from above that point since I couldn't find any oil higher the the block/deck surface. Even though I couldn't sit the area, I wiped my fingertips around the china wall/bellhousing area, and couldn't pick anything up under the black light. Anyone have anymore ideas?

 

I was just thinking about the China wall, that's why I asked. i have heard about HSR being kinda notorious for the china wall and not mating up too well. How's that cam for ya? I know you haven't wound it up too much, but do you think it would make some really good power up top? And how's the feel down low in daily driving? Let me know, and good luck on your oil problem.

 

So far I'm rather impressed with the setup. I know I'll get a lot more out of it when I get i tuned a little better and ditch the 2.73's. I can tell ya that I'm chirping 3rd with reving to only 4500rpm so that's not too bad, but I'm sure the SPEC III clutch has a little to do with that. And I think I found my oil leak. I'm pretty sure it's from the intake bolts loosing some torque since I never got around to retorquing them. They're supposed to be torqued to 30ft/lbs and tonight I set my tq wrench to 25ft/lbs and got about 1/8 turn out of each of the two rear bolts on the passenger side. Tonight it even starting leaking a little bit of coolant so instead of just retorquing them all down, I'm just gonna get new bolts and new gaskets and do it over, and think everything will be fine.

Tom

 

good to know you found the culprit. Do you have a 5 or 6 speed in your car? I was eventually going to get a T56 and maybe some 4.10's to help out my planned engine. Did you buy the complete SR package or just the intake and fuel rails? If so, how easy was it to get into proper tune with the chip and everything? Sorry for all the ? but I am getting closer (money wise) to building this thing and trying to get LOTS of info. Thanks!

 

I ended up putting in a T56 and am really happy with it so far. I just need to get some 3.73's or 4.10's. And I get the whole Holley Commmander 950 EFI setup with the Stealth Ram and it is really great cause I can make on the fly changes without having to crawl back under the dash, pull chips, make changes and put them back.

 

Glad to hear you tracked down the oil leak. Your setup sounds pretty fast especially when you get some 3.73's. With that cam and HSR you will pull hard through the traps.

On the hood isn't it funny how when we think we order the right hood it always just barely gives us the clearance we need. I think a hood rule of thumb should be whatever you think you need add 1" to it. I know I wish I would have had 1" more clearance.

 

Have you had time to get it dynoed? I was just rereading some of your last posts and people were estimating from 350-470hp. Have you gotten any numbers out of her yet? If not, do post when you get them!

 

I also forgot to ask earlier, since you went with the Pro Topline heads and a roller cam, did you have to use oversized pushrods? I have been told that if I went with a roller cam I would have to go with longer pushrods with those heads( I am going with aluminum though) so I was gonna try to get someone's first hand advice since finding a yes, no answer is kinda hard.

 

Well the pushrods that I went with were 7.300 and I think stock roller cam pushrods are like 7.295 or so IIRC. Even though I though, I was happy with the rocker geometry with the 7.300, if I had to reorder them, I would get the 7.350's. But don't just get them since they worked for me cause there are different variables, such as base of the cam, and my setup has the +.100 inch valve as most of the toplines do, plus mine has .010 taken off the deck and I'm using .028 head gaskets that are thinner then some of the fel-pros that alot of guys use. So if you're straying away from your stock setup, I would highly recommend a pushrod length checker.

Tom

 

Alright, thanks man. I was kinda wondering why I could never get a decisive answer to that question, I guess I know now. I suppose investing in some pushrod length checkers would be a good one....thanks again.

 

ok, one more crackhead question.....since you went with a complete engine buildup, as I am doing, about how much did it cost you to get the engine running only...no extra stuff and power goodies, just the bare minimum to get it running? I am wanting to get an estimate of how much I need to save...since I am only 17 and money is rather hard to come by. Thanks Tom, and post some times when you get a better rear end and get to the track!

 

ENGINE PICS PLEASE!!! NM Found em, looks good.

 

Does the Holley 950 ecm thing completely replace the stock ECM or does it just control the fuel and spark curve? The chip only controls the TC lockup on autos and the electrical on the engine right? So with a t56 and the holley 950, would you even need the stock ECM?

 

Well my ECM is in Arizona somewhere with the guy who bought it from me if that helps answer your question?

 

LOL! Yeah that answers my question. I've gotta get that thing. Anywho, could you shoot a rough estimate on what it cost you to build the engine? Just wanting to know how long and much to save.

 

Well I've got around 8500 in my motor I think if that's a rough enough estimate for ya, lol.

Tom

 

When you gonna dyno that thing mate :hail:

 

Well hopefully I'll have my LSD unit and gears here next week so hopefully the week after that.


Tom

 

Looks like we have almost identical setups. I'm just running a stock block with keith black hypereutic pistons (d-cup) and Way worse heads.

I wanted to ask you what commander 950 combo did you go with? Or did you just get the whole stealth ram pakage??

I just got the intake, ecu, ecu to laptop cable and the software new.
I bought the rest of the injection system used that leaves fuelrails, tb and injectors (28#'s)

Seeing as iäm about to wire the whole tbi setup to a multi-port setup i was thinking about the connections on the ecu. Does it need some kind of connectors/plugs for the wires of does it come with a base that can be custom wired??

 

Ok I know I am going to get flamed for this but if your are really into your car and want to take some time to learn, Check out the DIY Prom and you will see the the factory ECM can do as much as the aftermarket ECM's plus With items like The prominator, autoProm you don't need to burn Proms any more just load the Cailaberation, Modify, Then send it to the ECM. Plus if the ECM ever goes Bad You can get a brand new Gm Ecm for $85-$150.00 Well that is up to you but I know that the GM Ecm is up to the task there are a lot of 11/12 Second cars running the GM Ecm on the DIY prom Board and a few 10 Second.

Just my .02

 

Hey Tom sonds like this new motor is gonna be bad, but what kinda times did you run with the tbi?