more hp
 

was going to bolt on a blower but it will not fit under hatch so time to get more hp from motor
454 420 would like to get 525 out of it is it worth building a new motor if so what should i do to it or am i better off buying a motor already buildt and selling off the motor i have what should it cost to build my motor?
HAPPY HOLIDAYS TO ALL

look into methanol injection ive tried it had great results,,ho ho ho

Methonal injection isnt going to do much without a supercharger.

You can make some decent power out of your engine.

Depending on the hours, if low enough, you can keep your shortblock assembly and leave it be. The internals are plenty stout for 525HP.

Cylinder heads. A good set of aftermarket heads, will work better than the stock 420 heads. The GM heads you have can be improved, but by the time your done rebuilding, porting, etc, your almost at a new set of heads, that are NEW castings. Many of those old GM heads were known to drop seats, crack, etc. Something like a pair of Dart Iron eagle 308's are nice for the cost. If you want to spend a little more, something like the AFR 290, or 305 aluminum, or Dart Pro 1 310.

Camshaft. You'll need a decently agressive roller cam setup. Something in the 232/242, 236/245 duration range, with a 112LSA. You'll need to turn the engine faster than say 5000-5200 to see gains. with the right cam, lifters, springs, pushrods, etc, 5500-5800 isnt a problem.

Your intake manifold, if the original single plane, will work fine, and so will the stock 800 Holley carb.

If your engines have some time on them, and the shortblocks need to be gone thru, and a bore is needed, you may want to go with a larger domed piston to get the compression up from the 8.75 range, to around 9.5. Or you can always stroke it to a 489-496ci. 575-600HP is doable with a 496.

lots of ways to do it. All depends on your budget. I personally dont like buying "used" engines. Too many horror stories. Would rather build my own and know what i have.

your in chicago im in so.wisconsin can you refer a good engine builder

Depends on where you're at, but...

Russ at LAM in kenosha does nice work.

Opel engineering in Streamwood, Il is good.

Bill Lawson at ATECO engines in Waukegan.

Those guys are all familiar with Marine.

Lake geneva
who is your first pick or where do you go
MOTOR HAS ABOUT 500 HRS

Joe - Thats a quality post right there! it's a real shame that there are not more people on here that can provide valuable feedback like this with out flaming the OP or providing totally off topic and helpless information!

Sorry for the sidetrack but need to give credit where credit is due!

Merry Christmas!

Thanks
Jim

+1

Thanks guys. Merry christmas to you guys and your families.

Cig20, I'd rather not post online who I like or think is better. I have dealt with both LAM, and ateco, and both had good finished products. Several friends of mine dealt with Ted at Opel , and were very pleased. I choose to assemble my own stuff nowadays, and pay for machine work. Mainly because I enjoy Doing it

Thanks guys. Merry christmas to you guys and your families.

Cig20, I'd rather not post online who I like or think is better. I have dealt with both LAM, and ateco, and both had good finished products. Several friends of mine dealt with Ted at Opel , and were very pleased. I choose to assemble my own stuff nowadays, and pay for machine work. Mainly because I enjoy Doing it

fixx
 

dually,,call ted at opel,,he did all the machine work on my x18's engine..i dropped it off on a monday and all the machining was done on friday..and it was all spot on! i assembled the engine 13 yrs ago and it gets abused every weekend and the engine see's 6+ k rpms at any givin moment..

spend the extra money and have bob madera make the cam and have opel do the machining and assembly then dyno the engine..they also hace a cnc which most places dont..

http://www.opelengineering.com/

I can tell you how to spend a ton of money on 420's :)

I will say I spent the core money on parts that I could use on further builds. Buy it once and buy it right.
I refreshed my 420's with JE/SRP pistons, new ported aluminum Dart heads, best valves and springs. Most of my money is in my heads. But the heads have been on my 454's to blown 572's. After building the 454's to to their max I am now stepping over to the dark side. (positive displacement pumps on top of intake manifolds) Just do a cam swap and bolt on the blowers.

So in short what I am saying is build it with the future in mind. You will get bored with 525 soon.

I agree. I didn't recommend the blower thing as I believe in another thread he didn't have the room for one with his hatch.

But at 500 hours, I'd be getting serious about what you wanna do with that engine.

525 hp at flywheel or prop?

My buddy redid his merc 400 cyclones in his mistress last season, with stock heads, cam was 236/243 duration, around .575 lift, dual plane Edelbrock RPM intake and stainless marine exhaust with 800 holleys, made 521 hp @5300 I forget the torque nbumber but it was pretty good too, I thought it did well for stock head engine at lower RPM's

Jim just did a 502mag M1 Procharged and I was really impressed with the #'s. I think that would fit under the hatch. Shoot have a fresh 700hp 502 in the shop that would also work. cig20 just step over the 525hp mark and go straight to where you want to be:)

motor comes out this weekend and off to shop

Sounds like a nice 454 build. Roller cam?

Flat tappet Edelbrock RPM cam, I will see if I can find grind number...

We both have Mistress's and mine has stock 420 cams still with Merlin heads and Single plane intakes, we are with 1 mph of each other, I may do more cam this winter thinking there is a decent gain there, mine are also 460CI 8.4:1 so I wanna add a point of compression too...have abest of 65 on gps so farboats heavy as fuk..

You got flat tops in yours? Sound like a candidate for a pair of blowers....:bunnydance:

No blowers!! Lol I plan to keep it n/a and simple then I don't blow chit up all the time.... Simple and turn key

I hear ya...Been running blowers though for 5-6 seasons. Its all in the setup. No issues with breaking stuff.

Best bang for buck imo!

Matter of fact, I think mine idle, start better, and more docile than my buddies hopped up 420's. that's with 300 more ponies too. MPG, well, I lose that one. :lolhit:

Oh believe me... I know they can be reliable... In my case I would have to use pro chargers since height is an issue in hatch... And I am super budget guy... So buying blowers... Carbs... Fuel system... Monitoring... And all the other little things it becomes not budget... And as far as blowing stuff up.... 6-700 up and trs drives in a heavy mistress is not gonna be reliable.... So I keep it simple... To get my blower fix I jump on my buds 107 mph pro charged 353 formula... Now that's fun!!!

I love the challenge of squeezing the most I can out of simple combos without going broke... To run 65 in mine now with the power I have is pretty good considering everyone said I would be lucky to hit 60-62 with my power... Love the challenge!!

Ya that's not bad. My old 40' hawk with 400's best ever was like 61mph. My old 402 Formula weighed in at 16k lbs with no fuel on the trailer. With 600's, it ran a solid 68-70. which wasnt bad. with 400's those 402's did 53-55 on a good day. The TRS didnt like that boat though. I know all about the big old wave crushers!!

Love wave crushin!! need one on the great lakes!!

is it worth wild to have stock heads decked and deshoud valves and polish combustion chambers or better off going to new heads
other things are change cam to crane132596 valve spring crane 99893intake edelbrock RPM air gap and crower ioler hydraulic lifters
does this make sence

Bore notch the cylinders, bowl port the heads and decking the heads will raise compression.

Nothing comes up with that cam part # you posted.

sorry 132561 crane

You are putting a 420 cam back in. What are you trying to accomplish? If you are replacing the cam and want to achieve more HP without going to hydraulic roller why are you using the same cam? I thought you wanted to achieve 525? Same cam same heads will result in same HP.
Do a search "330 on roids" there are a few flat tappet cams in that thread.

Yep. Not much to gain there upgrading your 420 with that cam, considering its the SAME cam!!

This cam would be a step up. My buddy runs these in some old 454's.

http://www.summitracing.com/parts/cr...make/chevrolet

speed service, elston ave, chicago 773-545-1616 brian doss.

do not know much about building motors as you can see that a idea from another person on what to do what would be a good roller cam to use and would i be better off not using old heads a buying new one
just dont want to break the bank
dont know if exhaust makes a difference but i have aluminum 496 manifilds and risers

fixx
 

isky makes a good up graded cam for the 420 merc..has a sharp idle and real responsive...i have used this cam in many engines and it works great..i get the whole cam kit with springs and pushrods retainers shims lifters..the whole ball of wax for under 500 bux..

http://www.iskycams.com/pdfcatalog/2004-05/page162.pdf

have talked to a couple different places and now im baffled
rebiuld motorand install roller cam complete job with redoning existing heads prices are all over the board from 3500 to 7000 what would be a fair price everyone says they are doing the same thing and a extra 400 to500 to dyno by all

fixx
 

5500.00

What about trying to price a Dart short block or long block already built from dart?

I see new big block short blocks for around $3500.00 brand new. Add Dart heads and a stick for say another grand and your in it for about $5k..And you have a brand new dart motor? Is this reasonable for him to consider....Sell old motor to recoup some investment...
I just did it with 2 sbc darts and could be happier....(Note: I did use a cast crank because I am only turning 5200....)

fixx
 

28 donzi and 406's ?

don't think you ever mentioned what exhaust you have? you need to be aware in your cam selection or you will see water reversion into your exhaust. Valve overlap needs to be considered. Exhaust will also play a major roll in your final hp numbers with whatever engine setup you choose but even more so as you go up in rpms.

leaning towards the new motor and selling exiting motor
what is a 454 420 worth ?