Albert C4

Dreaming/Planning to repower my 88 vert. Considering Motown SBC short block. This can be bored to a 454. I would plan to bore to 427 for extra strength and build for FI.

Any experience with these blocks?

What type of intake and heads would work well with this setup?

FI system?

I'd need a new PCM...considering F.A.S.T. with a pair of wideband O2 sensors to failsafe the engine.

4L80E Transmission with Dana 44 rear end planned... how hard to install?

BTW they also make an aluminum block version.

How much torque can a convertible take?

Suggestions...recommendations appreciated.

bogus

the hardest part will be the 4L80E. It's not configured for the C4. I know it's been done, tho.

Fubar569

its not the bore giving you that size mainly...but rather the stroke....and when it comes to cubic inches size is king no matter what anyone says. forced induction or not, carbed or injected...the key to making big numbers is big cubic inches...stuff as big of a stroke and bore as you can into that block...and go with the aliminum block - the weight savings will pay off later...especially since you have a vert you WILL NEED to strengthen the chassis - i'd suggest a minimum a weld-in rollbar of some sort and look into adding any bracing you can. finish off welds and etc etc etc...

Intake? either a miniram or custon sheetmetal intake would be better suited...

Heads? with a blower/turbo forcing air in velocity no longer matters so much as overall flow. pick up the best flowing heads your budget will allow. many use brodix on big cube motors, or AFR is always a favorite. what's shaping up to be the hot ticket right now is AFR's 215cc competition CNC eliminator series head. i like the price at about 1600 bones and they flow really well for that price...

Dana 44 is a drop in, but you will need to fortify it. seek out ski_dwn_it and the others who have gone that route. ski used a spool and that was about all he did. some have used the custom D44 case with all the bells and whistles. with a big cube FI motor it wont be a matter of it if will break but when...my advice? save for a ford 9" conversion.

4L80E? damn good choice. if Raptor ever gets off thier *** they have a prototype tailshaft housing that will allow the 4L80E to be a direct bolt-in job to the C4...

basically you are looking at totally gutting the engine bay/underside and redoing everything...it will be a long and EXPENSIVE project

LT4POWR

I think an LS7 crate motor is worth considering.

BrianCunningham

It's a good swap, a lot easier than a LSX

There's plenty of forum members with big CI engines on the forum, hopefully they'll chime in.

Bad Karma

The nice thing about the Motown block is it's a beefed up Gen 1 style block. Mounting holes in the same place. Takes a distributor, it's basically a drop in, and you can run it on the stock wiring with a reprogrammed PROM chip. The LS-7 is a beast, but you have a lot of wiring issues to deal with.

I am also concidering the 427 Motown block, that or a more custome set up down the road.

90Z51

The block is a really nice piece. I built a 415 for a friend's Chevelle with a motown block. It's really cool to look at when you sit it next to a factory block. You just keep going "ooh! look at that!" and pointing out all of the nifty features.

Albert C4

So if I wanted to minimize the amount of items changed using a phased approach (i.e. spread my costs out over time), ...

I would only need to install a non-fi 454 Motown, put some high flow AFR heads with a mini ram and larger injectors. Reflash ecm and I'm good to go until I blow the trans or rear end?

Phase 2 would be tran and rear end.

Phase 3 would be FI and FAST PCM.

Albert C4

Would changing to a manual transmission be easier? I would actually prefer the manual.

Which manual/clutch would handle 800 hp crank?

bogus

ZF6 would handle that... in spades and be an easy fit.

Is this block a one or 2 piece rear main? I donno...

tjwong

I really doubt that the Mini-Ram will fit on the ports of the AFR 215 heads as their intake runners are a raised port design. Not to mention that using those heads requires shaft mount rockers with a .450 offset and offset lifters. A better choice would be the AFR 210 which do not require any expensive shaft mount rocker arms. The 210cc runners would be more than adequate for street use offering, decent low end repsonse in a larger displacement engine.

RandyJ75

Check out this web site, it is Forum member Diabolical Dave's build up of his 427 1990 vette.




http://diabolicalperformance.com/Dia...neModsPhI.html

Bad Karma

You could buy the short block and pick your own heads or buy their long block with their cylinder heads and just swap accesspries and go.

Curveit

... tjwong is correct, go with the AFR 210s. While Motown blocks are ok, their heads don't flow anywhere near as well as the AFRs. A single-plane intake(Edlebrock or modified Victor Jr) would be much better than the mini-ram, but someone would have to fabricate a plenum for it. I'm not sure what you mean in Phase 3..FI? And, I don't think the Fast PCM would improve much of anything over a correct program in your stock ECM, but you may have your own reasons for wanting it. Good luck with your project.

mike43725

go with brodix heads they're better heads than afr's imo.

Albert C4

"...with the AFR 210s. While Motown blocks are ok, their heads don't flow anywhere near as well as the AFRs. A single-plane intake(Edlebrock or modified Victor Jr) would be much better than the mini-ram, but someone would have to fabricate a plenum for it. I'm not sure what you mean in Phase 3..FI?"


FI=8lbs Vortech Forced induction! Should add 50% more hp.

Which intake works with MAF and batch fuel injection?

Albert C4

How is the transmission installed? How about the clutch?

Pelleplutt

Maybe you need a bigger radiator and more fuel supply ?

Pelle

-90 vert ZF6

BrianCunningham

It came out as a option in 89, so it's just a matter of gathering the correct parts. Which includes the trans, driveshaft, c-beam, and you'll want to upgrade to a Dana44 rear. That said
From
http://www.gmhightechperformance.com...0108sc_motown/

Not really a problem, you just need to order the right parts.