temp de-mod

[kutmup]

I can’t remember the last time I changed an engine for one with significantly less HP than the one that’s coming out. The ’72 is about to lose its 427 small block and get a L31 as a place holder. About a 200 HP reduction. I think of it as a teporary castration. The L31 is pretty much a slug as deliverd. I added 1.6 rockers, LT4 springes and the heads are ported. If I’m lucky it might make 300 HP.


Once it’s out I need to figure out why the 427 lost about 15 psi of oil pressure when it was started after its winter sleep last year. Once it healthy maybe I can swing some better heads and a roller cam upgrade.

 

[SuperBuickGuy]

sometimes you have to go backwards to go forward. Good thing you caught the oil pressure loss - it's a lot cheaper to fix when it's just a small loss rather than a total loss

 

[kutmup]

With a little luck it's still an easy fix. Fingers crossed. I'm betting that with the little engine we'll be able to hear the radio again...for now.

 

[mrvette]

With a little luck it's still an easy fix. Fingers crossed. I'm betting that with the little engine we'll be able to hear the radio again...for now.

:clobbered: I have NO tunes, just for that reason....convertible too.....

beautiful/purrfect day today, running around for a couple hours this AM.....

yawn.....:nuts::zzz:

 

[kutmup]

The little "corn popper" is almost ready. Heads are on. The rocker arm geometry is good and the valves are set. I need to add timing marks to the balancer, plug the oil filter bypass and prime the oil system. Then the fun can begin. I'm going to try pulling the engine while leaving the trans and bell housing in the car. The T56 is a pain to deal with so I'd rather leave in but I guess I'll see. I hope that putting the motor mounts in after mating the engine to the bell housing will let it slide in the proper plane to get the input shaft into the pressure plate.

 

[kutmup]

It's ready for a slingin' party.

 

[kutmup]

The 427 small block came out. I've never tried to pull one while leaving the trans and bell housing in the car. It came out with the radiator and shroud in place. Looked at two main bearings and they looked fine. With heads off it is still pretty hard to turn over. I guess we'll see.

 

[mrvette]

Hard to flip over with the HEADS off?? uh ohhh....:flash:

 

[kutmup]

I could not get the engine over the input shaft (maybe some added force would have done it but call me chicken) with the trans in the car so....

 

[kutmup]

The '72 has moved from building 2 where the projects reside to building 1 where the running cars that need to be washed live. We put about 100 miles on the new/old engine. For now I just used the 850 DP that was on the 427. I thought the fuel gauge had gotten stuck during the two year hibernation. 19.8 MPG in the same kind of driving that would get 14 with the 427. I'd rather have the missing power but good mileage is an OK side effect of the swap. The gearing was never optimized for the 427. Sixth gear is .5 and the ring and pinion are 3.55. In the hills around here sixth seldom got used. The 72 less cubic inches is more than offset by the 44 degrees less cam duration. It's very happy in sixth gear even on the hills as long as it's up to 1600 rpm. The BOSS will probably decide to use this 350 in her '74 but she wants to see what this will do in the quarter before she commits. We have a 4L60 for use in the '74. It has a 3.08 gear so were mine is turning 1670 rpm she'll be at 2020 at 75 mph.

I bet the 1 5/8 headers we have for her car will help the low end compared to the 1 7/8 that I have on the engine now. My wife is all about grunt in her cars.