cutlassefi

I try to share with everyone and I hope the owner of this build doesn't mind, but I just finished an EFI'd 455 45 degree D block.
Note; the owner of this build has to be the most patient man in the world, it's long overdue. We ran into numerous issues, from questionable lifters to a malfunctioning dyno control panel to ECM communication issues and more.

Anyway, here are the build specs;
45 degree D block
4.190 bore (Pontiac Icon pistons)
10.25:1
4.25" N crank
Studded and strapped
PP SFI balancer
Billet flywheel
Scat 7.00" H beam rods
Cloyes Billet timing chain
Holley Street Dominator intake, port matched and bunged for EFI.
1200cfm throttle body
1/2" open spacer
Edelbrock heads w/2.125 intakes, otherwise untouched
Accel DFI ECM and dual sync distributor
36#/hr injectors
Melling HV pump (purple spring)
Moroso Deep pan
Lunati Custom Roller cam (234/238@.050 on a 110, in at 109)
Harland Sharp 1.7 roller rockers (approx. .600 at the valve)
ARH 2.00 headers

536hp/566tq
Dyno sheet to follow.
And you'll notice that even with a 1200 cfm air valve, it was still pulling about 1.5" of vacuum at WOT. And people say an 850 is too big! I don't think so.
There was more in it. Some Mobil 1 and bit more tuning and rpm I think we would have been knocking on the door to 550hp.

Thanks

cutlassefi

Here's the dyno sheet, still trying to load the video. Won't cooperate for some reason. Notice the time on the sheet, 8:00p.m. Now that's dedication! Or foolishness, one or the other

Thanks

steel-and-fire

An over 500 HP/TQ Olds 455 with sequential fuel injection...that's quite a package. Who says you need an LS?

70cutty

Wow Mark, that's bad ***.

Magna86

Just don't tell us the $$$ spent on this motor. lol

morepwr

That is awesome! What is the engine going into?

Boldsmobile

Street build? If yes,

air cleaner used?

Are those the same temps it will see in use?

cutlassefi

A 65 or 66 Cutlass.
It had the Superflow hat on it. It's headed to Iowa. The temp on the sheet is still 30 degrees hotter than the ever famous Bill T. so not sure what you're driving at Boldsmobile. Just keeping test conditions apples to apples.

Thanks.

Boldsmobile

I was asking if it was dyno'd at the same temp it will see in real world use. I thought my question was clear, sorry if it was confusing.

The air cleaner is also not what it will see in real world use. Just confirming.

cutlassefi

Correct. I did it the same way Bill does them. Tired of fighting that battle but I do have earlier dyno sheets showing the difference in Hp at various temps if you'd like to see them. However based on those results I'm very sure Bill T wouldn't want to see them.

Thanks

therobski

Mark, great job! With the Holley Street Dominator intake, port matched and bunged for EFI there should not be any hood clearance issues with a stock hood?

Boldsmobile

I asked what I thought were clear and reasonable questions about your build.

I'm not benchmarking you to Bill.

cutlassefi

No it should be fine. The throttle body is only 2.00" high so that helps as well.

Barry Jones

Nice work Mark !!! I would love for you to build a motor for me someday ! Oh well , I can dream anyway😯

cutlassefi

Backstrom

Nice Work and good numbers!

I can't help comparing this to the 463 you made for Edin, as I'm hoping to be close of hp/tq on my build.
I noticed that this one had 4 degrees less duration on exh side, and installed on 109 vs 108 on Edins.
What i did see on this was a good increase of hp, but a little drop in tq, and at a higher rpm. Is this a result of retarding the cam only 1*?
As you know, i'm sucking info like a sponge!
Thanks /Anders

cutlassefi

No, the higher hp at a higher rpm is due to a few things;
This 455 has a longer rod, 7.00" vs 6.735. It also has a single plane intake vs a dual plane. And these Edelbrock heads have a larger entry area than Edins Procomps. Plus this had 2.00" headers vs Edins 1 7/8".

I thought about advancing the cam a bit but it seemed a nice compromise right where it was. This is going in a 4 speed car so it should be loads of fun.

Hope this helps.