351 Cleveland Twin Turbo Build

[Eliminator Kid]

I am planning to build a 351 cleveland twin turbo. I have some questions and would like opinion. I am planning to get two Garrett GT3582R turbos. I have a shop in town called speedlab that said if i supplied the turbos and intercooler they will do all the custom fab work and guages for 6,000. I have to build a low compression 4 bolt main forged motor. My question is how do you get low compression and what would i need. I wanted to get a 4 bolt main block or a man o war block that is rated for 1000 hp. Then i wanted to get aluminum heads, intake. All forged parts that i can get. Roller rocker and roller lifters. I just need to know what i need to buy or do to build an 8.5 maybe 9.0 compression motor that can handle say 600-700 street power on 15 lbs boost. If possible 800-1000 on 20 lbs or 25 lbs boost. Let me know what you guys think. I have been told it can be done and it is very doable, engine builders let me know.

[conv cat]

First, most all Cleveland engine builders agree that two-bolt main blocks are every bit as strong as the four-bolt's are.

And since there's little (or no) virgin 351C blocks available, you'll have to bore a minimum of .030 over. High performance Cleveland engines have dry intakes and water jackets extremely close to the cylinder walls. They're notorious for running hot once they're bored.

With a twin turbo setup, your block will most likely give out the second or third time you hold the pedal to the floor.

If you're willing to spend the kind of money it would cost to build that twin-turbo 351C, let the Cleveland engine-building pro...Jon Kaase...build one for you.

[Eliminator Kid]

i get a man o war 351 block. They supposedly hold up to 1000 and up hp and i have heard good things about there product lines. What has to be done to build a low compression motor? The reason i need a cleveland or something in the general realm is that i have a race built bulletproof c6 that has a cleveland bellhousing.

[Art]

Cleveland bellhousing bolt pattern is the same as a 351W, 5.0, 302, and all 6 bolt 289's.
As far as building a low compression motor, when you order your pistons you have them made for what ever compression you desire.

[sixt9coug]

i say go for a 351W. they have a better aftermarket that will allow you to do more things for the same money. The availability of internal parts and blocks will just be better as well. seeing as you have some cash to burn, why not just go for an aftermarket Windsor block and some good forged innards. some nice AFR heads will flow better than the stock Clevelands ever will and the block will be more able to handle the power.

not to mention that the Windsor will leave more room underhood for the piping. unless you plan to totally ditch the shock towers of course...

then if thats the case.... why not go Big Block...

[leonbray]

What you are proposing has been done many times in Oz. Clevelands running 600 - 700 hp with twin turbos reliably - 800 hp occasionally and 1000hp on dyno pulls only (unless you want a carton full of bits)

Turbos are generally mounted at the front of the engine, blowing into individual inter-coolers that exit over the radiator to twin throttle bodies. You will need a bunch of thought on how you cool the turbos and engine bay as they will generate significant amounts of heat that will cause other components to fail


If your machine shop can't show you where they have done this before then you should forget it. The dyno pull guys down here reckon that Clevelands are no good above 1000hp

Be prepared for al lot more money than the engine for the transmission, tailshaft, diff, axles, suspension, brakes, boxing the fram or subframe connectors, traction bars and tickets

Most of the tough street V8s are going away from turbos to powerdyne (Paxton style) or Eaton blowers on stroked Windsors. Cleveland bits are getting too scarce (an I have 5 spare 302/351C engines sitting in the shed)

My advice would be to build a really nice 427 Windsor with edelbrock injection - it will start every time, won't give you big heat problems under the hood, ad it is streetable

[greggieatthebat]

E-Kid- One of my coworkers used to be co-owner of another custom turbo shop in town. I can't find it now and he's not here today, but it's called something like "Stone Tech". There's also a shop in town called Speed Dreams (www.speeddream.net - server appears to be down right now) who was featured in Muscle Mustangs and Fast Fords last November, installing a "Hellion" turbo system (Hellion is also in ABQ). Your options are numerous - shop around a bit, find the guys that you like working with. They'll give you the best results.

[Cougar351]

My buddy has a twin turbo 351C Mach 1.

He has gone through two blocks, and had to drop $1800 on forged internals. You're looking at alot more then $6000 at the end of the day.

[705.0Merc]

I ditched my Cleveland, not enough room! I threw in a high mileage roller 5.0 with a single turbo, I will never go back to the 351. I have seen guys making over 600hp and 700tq to the wheels with a built 5.0, not a stock block of course, with a single t-70 15-20 psi. This is where I did all of my research for my turbo settup. Turbos are great because the motor can be very mild and still make a ton of power.
http://www.turbomustangs.com/smf/index.php

[Cougar351]

http://www.cardomain.com/ride/733087

Thats my friends cardomains, you can see some of the BS he has already gone through.

[dfwcatsclub]

Just curious if you've found the twin turbo buildup going on over on the 351C forum (Network 54). A guy named "Ben Sinclair" has been doing a very similar build and just posted pics of the rigging in the car...lot's of fun but he's got a ways to go.

[fast70cougar]

It makes me a sad panda to hear that the 351C aren't the best for a twin turbo motor. That was going to be my next project.

[Royce Peterson]

I think a 351C is as good a candidate for a twin turbo as any other engine. The thing about using a Cleveland is that it will cost you dearly compared to using a 351W or a 5.0 to begin with. There are off the shelf kits to turbo a 5.0 that will save huge amounts of time and money.

A short block that will take 800 horsepower is going to need to be built right. You are likely going to pay $4000 or more just for the short block parts and machine work, provided you have a good block to start with. Figure another $2K for cam / custom roller rocker setup from Jesel or T&D and custom pushrods. Then you need to start thinking about a custom FI system.

All in all a twin turbo Cleveland ought to cost $20 - $25K finished I am guessing.

[Cougar351]

If you pay someone else to do the work and buy all new parts, I would say about 20 grand. But so far my buddy is only about 8 grand deep into his project, and it SHOULD be on the road. He had to go with smaller turbos then he wanted, as well as forged internals. Should make about 750hp at the wheels give or take.

He'll be blowing my doors off though, that much I know.

[GYRHEAD]

On the relative difficulty scale, this project is 14 out of 10. In addition to the huge cost of hardware, there's the tuning. You'll need a LOT of chassis dyno time, wideband 02, boost referenced fueling, and ideally some way to detect knock and pull timing to keep the motor alive.

This stuff is hard enough on factory engineered Turbo EFI cars, it's more so on custom fabbed stuff. Add in what I assume is a teenager's budget and this project will likely be a long term headache.

A friend built a twin turbo 351C for a Pantera, and the all-in costs for this 850 HP motor exceeded $50K. Granted he went with Fontana block, alloy heads and the best money could buy.

Build a big cube V8 or go with a supercharged 5.0 and you'll likely have a better chance of sucess.