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I thought of getting a 427 as a few was recommending it. Ended up with a 388 instead so it would be easier on the driveline with less torque. Then when I graduate from school and start my second life chapter of a job, I'll get the motor refreshed and go 427 then and change cranks if I desire it.
 

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Discussion Starter · #22 ·
Pat g just tuned an 388 vette with stock ported heads and blower to over 1,000 hp. Basically the same build I'm doing.
Link to the build? Should I assume it’s turbo?


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Discussion Starter · #24 ·
I finally found the post and link.
Post 3592 in the “do to your V” thread.


I called Thompson’s today. They say they don’t have them now…. which makes no sense since they build to order. Maybe they don’t have the cheaper components?

dagnabbit
I want a 7Liter

so bad

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Discussion Starter · #25 · (Edited)
I may have found it.
Another shop has essentially the same short block with Callie’s internals (8cw)
for under 6(!).
I have to pick it apart to see how many differences…


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Discussion Starter · #26 · (Edited)
Here’s what I found: http://www.competitionproducts.com/mobile/Dart-Pro-Assembled-427ci-Chev-SHP-LS-Next-Short-Block-Inv-Dome-1111-w_66cc-58T-Reluctor/productinfo/DRT93861427-58/CP Dart assembled Dart LSNext
Assembled by Dart, balanced, fitted, etc.
Apparently this would be the match to Dart’s 03484272 short block, except that the rotating parts are named here “Callie’s/Howard’s “ while the Dart catalog doesn’t actually state the name or COO of the parts used in their own offering. The Dart cataloged version (03484272) is over 8K online.
Yes, I know Compstar is not domestic.
I know that Competition Products/ Howard’s Cams has been around a long time. Do any of you have experience with them?
This is a Dart SHP LSNext built by Dart, I feel pretty comfortable with that.
Competition Products and Howard’s Cams are one and the same, it appears.
What are your thoughts?

I want to go 427 for the silliest of reasons (vanity).
I wanted to do it with my LSA block but ALL info i find says NO. The LSA is not the block for sleeving; too much flex, short life span.
I wanted to stay alloy but apparently the LS7 has a host of issues against it and the next option is a Darton-LS3, which quickly outspends me.
So, I can build my LSA to 418 or smaller OR… look at iron.
Another point: the option to sell my running high mile LSA for pretty good money, now makes this reachable.
 

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Discussion Starter · #28 ·
Just toss the 427 badges on and call it a day


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Hah! Nopes to that, can’t do it.
Vanity may be superficial but Real Vanity requires commitment.

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Hah! Nopes to that, can’t do it.
Vanity may be superficial but Real Vanity requires commitment.

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There are lots of great engine sizes but 427, to me, is an iconic number.
 
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427 (badges) + aluminum block I mean come on that’s a rare combo


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Discussion Starter · #32 · (Edited)
Not that rare. Literally every LS7.
Agreed. I considered that route, but of course the internet says the LS7 is not the preferred block for boost. I know….. that I don’t know.
What are YOUR thoughts on it?


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What are your plans for the huge pile of parts you already bought if your looking at short blocks? Your already sitting on a mountain of stuff!!
 

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Discussion Starter · #34 · (Edited)
What are your plans for the huge pile of parts you already bought if your looking at short blocks? Your already sitting on a mountain of stuff!!
It’s true but most of it I’ll still use; exhaust, cooling mods, pulleys, etc.
The parts that I’ll clearly need to move are the 4” TSP 8bolt crank, matching Wiseco 4.080 pistons.
The parts that I’ll still need but may have to consider revising or reconfiguring for the larger displacement:
Matt’s cam, ported TB, injectors,and prob more things.
Is it true that the Dart block uses different lifters/ lifter retainers?

All of these parts have been purchased so long ago that they aren’t returnable but I’ll have no trouble selling them.
I plan to port the blower and snout but a real question is how restrictive would the 1.9 be (even if perfectly ported) to a 427?

and what about heads/valves with the big bore…..

Yes, it’s a whole new plan, but at least it’s back on the beaten path rather than the weird square 418. Hey, at least I have the ALM hat and dual 340 pumps done(!)
I am very close to pulling this trigger, y’all tell me if there’s a serious error in this offering, please.

The one thing I noticed is that Thompson does offer a warranty on their builds, but these guys and dart don’t.
 

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Agreed. I considered that route, but of course the internet says the LS7 is not the preferred block for boost. I know….. that I don’t know.
What are YOUR thoughts on it?


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LS7 block is no good for boost but it is an Aluminum 427.

You need to either go Dart Al, LSR or other more expensive options for a 6 bolt setup or some use a resleeved GM block but there are limits to that setup if not filling the water jackets. Just depends on power goals
 

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To be totally honest I’m not a super technical motor guy, I know enough to be dangerous, I’d imagine your cam would still be fine to use, possibly the injectors depending on hp, may have to 1300’s. Matt would be the guy to talk to, he builds some nice heads and since you have his cam it seems like the best option IMO. If you need a 102 I have a nw that I’ll let go on the cheap(got a great deal on a 103) you’ll also want to look into a larger intake if your porting the blower and heads, that soler won’t cut it. I’d recommend the ddp intake, that’s what I’m running. I’m sure you can offset some of the cost by selling stuff off . Best advice I could offer would be pick Matt’s brain about your thoughts. As you know he’s great to work with and very prompt with responding
 

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Discussion Starter · #38 ·
LS7 block is no good for boost but it is an Aluminum 427.

You need to either go Dart Al, LSR or other more expensive options for a 6 bolt setup or some use a resleeved GM block but there are limits to that setup if not filling the water jackets. Just depends on power goals
I was confused for a moment but I think your answer was to “if I insist on having an ALLOY 427…” then those would be my choices. Got it. and I really like the LSR except for the price. The LS3 with Dartons seems to be popular and thats what a youtube bunch had in their Leroy car… and it certainly took abuse. However, for the same money, the LSR looks a bunch better than the LS3.
I have almost decided to forget the alloy and move on with iron just based on dollars.
1. The full skirt Dart SHP LSNext being an iron six bolt (and i’ll be looking at heads to match), are there any strength issues with these?
2. Do the Dart blocks use the same lifters and tray arrangement as the LSA?
3. If I find availability on the LSR I could look at that path.
4. I have a 4” forged steel -not fully-counterweighted- crank… bad idea in an alloy block?


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