[TheSilverBuick]

Just to compare numbers. I am still contending with some vacuum leaks, so the new intake having a higher manifold pressure isn't surprising, but the test is also ran at around 100rpm lower than the first test. So I may dial the target rpm up to 825rpm and run the test again to see how it compares. The extra rpm "should" pull a bit more vacuum and really compare the two charts.

The stock manifold, with the short runners and comparatively small plenum volume runs about 3kPa from low to high, and the new intake ran 1.5kPa from low to high, which I is expected from the much larger plenum volume** combined with the runner length. When I re-run the test at 825rpm I don't expect the variances to change, just shift the wave to a lower pressure range (higher manifold vacuum). The average shift is ~4.75kPa more pressure or 1.4inHg less vacuum.

**The new plenum volume is approximately the same as the engine size, not counting the runner volume.

Test 1 from January 2015. ~825rpm, ~34kPa - ~37kPa


Test 2 from March 2016. ~713rpm, ~39.5kPa - ~ 41kPa.

[TheSilverBuick]

Incredibly enough, a run of semi-blank cams with extra big lobes were made and put up on E-bay a few days ago. I instantly bought one. It has a lot more material on the lobes than my last semi-finished cam that I had ground with low overlap and a turbo in mind. These unfinished lobes are larger than the support journals so have to be ground down to at least that point (and some base circle reduction . I'm going to hang on to it for a while before getting a grind put on it, but I'm seriously thinking of when I do get it ground to simply tell the grinder to take the bare minimum off for the maximum amount of lift and duration the semi-blank will allow, with consideration of what the LCA options are.

Not one bit of paperwork with it, but its not like I expected cam spec's or anything anyways. Payment was to long time OHC parts supplier Woodland Motorsports in Utah, but it was shipped from Delta Cams in Washington.



Lots of room for grinding!

[Jeff Hamlin]

Delta Cam, I've not heard that name in awhile.
IIRC that would be OLD STOCK from an early venture.
Neat none the less. Have a grinder in mind?

[TheSilverBuick]

If they had old stock, they'd been sitting on it a while. There is a thread on the Yuku forum that talked about Jerry getting a run going, and it appeared to have happened. I'd guess these are new castings.

No idea on grinder yet, but will likely send it to Colt Cam's in Canada (I've contemplated Crane and Bullet, and now Delta). They did the grind for my turbo cam and were the ones that did the grinds for Prima-Tech (stage 1 and 2 cams). Between crossing the border and the currency exchange rate then it was a pricey grind. In theory it could be 23% cheaper to get it ground now compared to when I had my last one done....

[TheSilverBuick]

I thought I'd drop my spare 250 crank into my 230 block to see what clearances I have for possibly rigging up piston oil squirters (to cool the pistons when I put boost to it) when I ran into an unexpected hiccup... The counter weights tag the oil baffle mounting tabs, d'oh! In the 250 block the two mounting tabs have been replaced with a single one in the center to clear the counter weights. So I ground the rivet head off, punched out the remainder and removed the baffle and ground down the tabs to clear. I'll make new baffles and make new mounting points, likely to the side of the block.

That's not supposed to hit...


Or there....


When I turbo the engine, because of the cast iron head and the relatively poor chamber design (by modern standards) I want to try and use every trick in the book to keep detonation at bay. I've already started with reverse flow cooling so the head get's the cool radiator water first, and I've separated the exhaust manifold from the intake to keep heat transfer down, and I'll be using an intercooler and possibly a water/meth injection system, but one other trick is to spray the underside of the piston with oil to help cool the piston and prevent it from being a hot spot in the chamber. It's common in many modern high compression and boosted engines. My thought was to tee off the external lash adjuster galley line and run it to an internal oil rail that would have squirters at the bottom of the cylinder bore. Now that I've re-mocked up the crank in the block, I'm not so sure I can fit a system in there.... =/

Those Pontiac engineers packed every thing in there pretty tightly! I don't think I could get even an 1/8th inch line between the block and counter weights and I think I'd need at least a 3/16th line to have a meaningful impact. That bulge next to the drain back hole (running parallel to the block) is the oil feed line for the mains.




Going to the other side may be possible by drilling a hole to the exterior of the block right at the base of the bore and running a line from the outside to each cylinder. I need to mock up with a connecting rod in place to really see how much room would be available. I'd also have to contend with the exhaust heat as the line would be between the block and exhaust manifold/header and running an oil line to the other side of the engine where even with the turbo I'm going to try and keep all the oil lines on the passenger side. I'm becoming less inclined to try it, at least at this stage.





The other thing I noticed was how poor the oil drain back set up is. The size of the drain back holes are more than adequate, but their location is right above a counter weight that is in it's upwards throw, so it would seem to me that a fair amount of excess oil is getting flung around as crank windage. Not sure what I want to do about that yet. Again it's a room issue, but if I can find a way to extend the drain backs past the crank, I think that would be best. An extreme measure would be to tap and plug the drain backs at the bottom then tap the drain backs from the outside of the block and run a line to the oil pan or even the block's oil filler cavity. This would maximize oil control below. Alternatively would be to build a baffle that carries the oil up against the side of the block, shielding it from the crank windage.

This picture again. Like grind out the hole to flow towards the block wall, then put a baffle between the hole and crank. Even if it covers most the hole, if it's been opened towards the block side it should still flow back reasonably well. Securing the baffle in place I think would be the real challenge.


The 4 vertical ribs going down the side of the block are the oil drains. I would only need to tap into cylinder 3 and 6 and make them drain back to the oil filler cavity, one already drains to the oil fill cavity and I think #5 could be drilled to connect internally to the oil fill cavity. Only really needing to mess with two make this option sound more appealing.

[TheSilverBuick]

I think I will re-route the oil drain backs. Looking at the block again, I only have to run two external lines and tap into one of them from the oil filler cavity. I check my taps and the hole size is perfect for a 3/8th NPT tap. I think the returns are 9/16th and the tap asks for a 37/64 bit, which 36/64 reduces to 9/16, so plenty of meat to tap into.



I didn't have a 3/8's plug on hand, but this adapter shows it'll work well. I'd probably use some loc-tite on it and likely drill the tiniest of holes in the the plug just so oil doesn't permanently backup in there and cook.



I need to get a 37/64 or 9/16 drill bit to tap the block externally at the base of the returns and to be able to thread the appropriately sized fittings to it. Then I'll drill and tap corresponding fittings to the oil fill cavity.

[Formulabruce]

very interesting! , and the pics sure help explain whats going on!

[TheSilverBuick]

​Finally got the intake sealed up well enough I'm ready to really drive the car around. I had some issues with between the runners not being sealed up, but it also had a gasket alignment issue. I got a standard tin intake/exhaust gasket on it and with the intake and exhaust being two pieces now it had sagged down towards the rear. loosening the exhaust manifold and shifting the gasket back up and then tightening the manifold back down seemed to do the trick.

The engine is running at a cold high idle (~38ºF CLT temp), but fired right up and is running well.
https://www.youtube.com/watch?v=6_eAOO-iBAA

[TheSilverBuick]

I removed the spoiler from the deck lid today. I've never liked it. It's more of a Camaro thing. The paint under it is a bit rough, so going to try some paint cleaner on it. I'm going to simply RTV in some black plugs in the bolt holes to seal them up for the time being.

[TheSilverBuick]

I finally went and got actual plugs for the oil drain backs. I was concerned about oil being trapped, and cooking/sludging, at the plugs so I took the tiniest drill bit I had and made a drain hole, then to promote sticking it to the wall of the block rather than drip onto the rotating assembly. I also numbered them to the corresponding cylinder to make it easy to re-install them after I remove them for the actual machine shop work.





I also drilled the first two holes in the block to re-route the return oil. The first one was a difficult angle to achieve (why the oem didn't do it!), but I finally got the drill bit to bite and have one re-routed internally to the oil fill cavity. So this one will drain back behind an oil baffle. I'll probably run that baffle a bit below the oil pan rail to be sure it clears the crank.


The last hole I drilled today, and tapped, was the first drain. There is a nice block in the casting where the passage changes direction so I centered up and drilled a 9/16th hole there and tapped it for a flared fitting. I will add a corresponding fitting in the oil fill area to drain too. It will likely "disappear" from sight when the fitting and line are painted Pontiac Blue.



I need to drill and tap one more return line for the rear most drain. That one is a bit more complicated due to the casting ribs from the bell housing, but should still be able to make it work.

[amcmike]

Very cool and unique project!

[TheSilverBuick]

Been still working on minor vacuum leaks around my crap welding around the flanges and injector bungs. Not surprising though, given this was my first attempt at something like this. I think I got it to a reasonably sealed up point and drove it to work yesterday.

Driving home I noticed it was smoking quite a bit, like before I hooked up the crankcase vacuum to help the rings. Also was seeing some oil pressure instability at higher rpm. When I got home I checked the oil level and was dang near two quarts over full. Not sure what I was thinking when I changed the oil two weeks ago, but clearly wasn't counting bottles.

So I pulled it into the shop and disconnected the external oil line return and using a spare distributor as an oil priming tool quickly pumped out around 2 quarts.



Then driving to work this morning, I wound it up some. Pulled to 5400rpm, with no indication of laying over, but was starting to see some oil pressure instability again so I lifted to get it to shift and then put the pedal back down until ~4,800rpm in second.

These oil instabilities are why I'm working on external return lines on my next engine as I'm pretty sure it's oil aeration causing the issues. There is a sweet spot for the oil level to be at that it seems to like and I must not have it right yet after yesterday's oil volume adjustment.

The white line is RPM, I was in 2nd gear then it downshifted into first and ran up to 5400rpm and I lifted to get it to shift into second early and hit the throttle again. I need to look at my sensor lag settings as it shows the TPS and MAP signals falling after the RPM, which should be the opposite case.

[TheSilverBuick]

Since I'm getting ready to go to the track tomorrow and test for any improvements, I thought I'd review the data gathered from last year passes for review. The answer is it doesn't look promising for an improvement from my intake.....yet! I've plotted the rpm acceleration rates in first and second gear from my tests two days ago against the drag strip passes from last year. The soild white line is with the new intake and the shadowed white line is from last year's passes. The caveat is where I'm really expecting the improvements to be is in the 5,500+rpm range. It's the rpm range I built the runner lengths around. The engine before started to nose over around 5,500rpm and really choked around 5,800rpm, so it will be interesting to see if I've overcome that. I still have some oil pressure flutter as of this morning, so I'm going to pull more oil out of it tonight and hopefully be able to sneak up on the right amount (if I don't get it right tonight) tomorrow by adding a little at a time. I know there is a happy medium, I had it at last year's event.




I also finally got the Raspberry Pi 2 running the dash setup on boot up. It's roughed in right now as final shaping and arraigning of the gauges will be done on the small screen in the car. The boot time is around 45 seconds, which is down from a minute and twenty seconds.
https://www.youtube.com/watch?v=6sv-PvD5NMw

[TheSilverBuick]

Due to weather running the track was a bust. The wife and I did drive 90 miles out there only to find the guy who owns the timing equipment had cancelled the night before. A few of the organizers were there and still tech'd some cars in and did some flag drop 1/8 mile grudge racing and whatnot until the rain started, which was about 30 minutes afterwards.

I made one pass and the car pulled cleanly to a data logged 5700rpm, oil pressure was good but still had some issues with vacuum leaks and the rains came as I was going for a second pass.

All dressed up and ready to go.


Put 190 miles on it in one day and drove cleanly out and back. The air temps hung around 55-58ºF and some rain.


The Firebird is parked over on the right and the engine drew plenty of attention from the 10am gate opening to the 11am run time.


My wife took this picture of me reviewing the datalog after my first pass. Rain drops were just starting to fall.


So we went into town for lunch before heading home. We walked the main street looking at the various cars out. Got in just before it started to rain again.



I'm going to put the 4bbl EFI intake back on, and start work on the new intake. One of the local hardware stores is closing down and I bought all their sheet metal for 50% off so I have the materials ready to go, just need to find the time.

[Formulabruce]

great pics!! Looks like you are having Fun !!

[TheSilverBuick]

Thanks! Yes despite not getting any time slips, it was a good day. I took a vacation day from work to go, but at they say, even the worse day "attempting to race" is better than a good day at work

[TheSilverBuick]

Went and picked up the mother load of "stuff" this last weekend. There is so much I'm not even sure what direction I'll go first, but I'm leaning towards staying the course with the block I'm working on, but possibly using the pistons on the rods and crank I have. Then get one of the heads ported and set up, or may continue on with my current head project and save ALL the good stuff (except the forged pistons) for when I have the turbo R&D completed. To say I am excited is to under state it!

Got a u-haul trailer of stuff! Including 6 blocks, a couple heads, some cams, two '69 Firebird core supports and lots of miscellaneous parts, including a random Atlas DOHC 4.2 head.


Used a ramp, and some help to get the engines in, but didn't have too much trouble with a sheet of plywood and the engine hoist.


A snap shot of most the stuff. The engine stand came with the engine! There are accessory drives, starters, pulleys, tubing, misc. hardware, couple oil pans, etc.


A couple of cams. They may or may not be high-performance, but will check them out later. I already have my turbo cam for my main engine goal.


Cleaned up 250 head. Basically the same head that is in my Firebird now except it has nice new seats. I did get some valves so have to decide how I want to proceed from here.


This head has beehive springs on it. The stems measure ~.100" above spec, so would need to be cut down. I am considering just shaving them ~.050" and with my turbo cam needing ~0.050" taller stems, would put them right in spec. I'd have to come up with 0.050" shims for under the lash adjusters to keep the geometry good. There is probably some wiggle room on the lash adjuster side though.


This is the beehive head, I believe it's a 230 1bbl head. Pretty high compression on a 250 engine, but I think if the chambers are modified the compression with a felpro gasket may be right where I'd want it for the turbo engine. I've been working with a 1bbl 230 head already, so I have something to test with first.


A fully machined block and crank. A set of pistons and rings for it as well. I have a good set of OE rods with arp bolts already. I may confiscate these pistons for the block I've been modifying.


An engine just waiting for a good head... This is just going back into it's wrapping (and maybe more wrapping) and will sit in the corner until I'm pretty much done with all my turbo R&D work. Not sense in risking it on stupid tuning or other mistakes. It has a nice set of forged rods in it, and may even be a stroker engine (off set ground journals with longer rods).



Three of the engines, including the machined bare block, have all the cross bolt bosses cast in. It would likely take a TON of rpm and boost to require cross bolting, but if I ever reach that level of eccentricity I could have main caps made to take cross bolts. 7 mains is already pretty hefty though.

[Formulabruce]

wow, what a haul!! hope you get too use most of it.. Its all 250 stuff, or any 230?

[66sprint6]

Wow, what a score. It all looks really clean. Looks like you won't be needing any parts for a while.

[TheSilverBuick]

Originally Posted by Formulabruce

wow, what a haul!! hope you get too use most of it.. Its all 250 stuff, or any 230?

50/50 split. The blocks with the cross bolting casting were a '66 only thing, so those are all 230 blocks/engines. Two are 250 engines and one I don't know for sure, but likely a 250. Likewise on the heads and timing belt covers.