Here's a loaded question: Which engine would be best for an RCR build?

[Phillip]

I know, I know. I'm probably going to get 100 different responses with 100 different opinions. But I gotta ask. Looking at possibly a GT40 build.

I was originally thinking of a 428FE engine for a build. But I was barraged with people telling me that I'll be tearing up the transmission in no time with that much torque unless I want to spend $20K on the trans alone, which I don't (I was hoping for more like $10K for each and I can do my own engine work and the internet is flush with engine builds).

I'm a real fan of torque, hence there's no replacement for displacement. So I was re-thinking about a 302/347 or possibly a 351W/408 engine. And is a Windsor engine preferable to a Cleveland engine when looking for a candidate? Seems everyone builds windsors for these cars.

Performance goal is to be able to keep up with a new Corvette. So I'm figuring somewhere near the magic 500hp/500tq engine. I've always built my engines with good torque in mind and let the hp number fall where it may. Max rpm's would not need to exceed 6000 rpm's or so. So no 8000 rpm screamer here.

Any opinions???? Anyone? Anyone? Bueller.....Bueller?

 

[Tom]

seems to me that at $10K, you can find a G50/50, or a G50-86(?) which are pretty capable transaxles. Unless you are running slicks, 500lb-ft should not overload the trans, since normal street/R compound tires will break loose before you hit peak torque in low gears.

 

[Fran Hall RCR]

I would suggest a 930 box personally

 

[Howard Jones]

I have said this before several times. Spilt budget on engine/remainder of power train, 40/60 respectfully. I spent about 6K on my motor and about 15K on the rest.

I am sure you can build a very effective 351 Winsor for $6K and then use the other 14K on a Porsche G50 with all the good parts. Fran likes a 930 and I don't disagree, but the G50s with good internals is plenty strong.

Give California Motorsports a call and have let them help you on selecting a gearbox. I like them and they did me right but there are others that can source a used box for upgrade and rebuild. I would not buy a used box and then have it rebuilt after the fact. You can end up with a lot of used up pieces that will use up the gearbox budget that way.

A good used 351, rebuilt with 10 to 1 pistons (pump gas motor), hyd roller cam, and good heads like the alum Eldenbrock RPM performer, running a simple Holley 750 DP will make well north of 400HP and cost you right at $6K in parts and the machine work if you do the assembly yourself.

All this stuff will last the life of the car if you drive it like it's you money.

I didn't catch the RCR car you want to build. GT40?

 

[Walter Williams]

I have a 347 470 hp 450 trq getrag 01e 6 speed from scott dewitt... He said it will handle 500 hp.... So far so good..

 

[Jac Mac]

Plus 10 on Howards post #4 above, I freshened a 351w along those lines a while back, owner put it on a RR Dyno and damn near ended up in a punch-up with Dyno operator who simply would not believe it had not been stroked as it out performed any others he had tested.

 

[Larry L.]

And is a Windsor engine preferable to a Cleveland engine when looking for a candidate? Seems everyone builds windsors for these cars.

Clevelands have an inferior oiling system/design...in stock configuration anyway.

 

[Jac Mac]

Clevelands have an inferior oiling system/design...in stock configuration anyway.

I can live with the oiling system, cylinder wall thickness, core shift and main bearing web material are the real issues on stock blocks.

 

[Rod Brace]

Jac Mac is correct the foundation (block) is major you can steel cap, main girdle,stud it to help but stock blocks were production pieces designed for only so much horsepower and torque above stock. I know people would think it is sacrilege but it is hard to beat a ls chevy for weight,cost,power output and aftermarket support.

 

[Larry L.]

...it is hard to beat a ls chevy for weight,cost,power output and aftermarket support.

Only a diehard Ford or Mopar fan would deny/attempt to argue against the absolute gospel in that. 'Far too easy to completely destroy their position with speed shop catalog price sheets/dyno graphs, etc., etc., etc....especially the "aftermarket support" thing.

 

[Jac Mac]

I know, I know. I'm probably going to get 100 different responses with 100 different opinions. But I gotta ask.

I was originally thinking of a 428FE engine for a build. But I was barraged with people telling me that I'll be tearing up the transmission in no time with that much torque unless I want to spend $20K on the trans alone, which I don't (I was hoping for more like $10K for each and I can do my own engine work and the internet is flush with engine builds).If you must have an FE why not just do a rebore & crank grind on a 390, Edelbrock alloy heads and 4bbl that shouldn't owe you more than 6k or 7k in the USA & you said you can assemble yourself. Pretty hard for joe average to pick a 390 from 427 as long you say nothing.

I'm a real fan of torque, hence there's no replacement for displacement. So I was re-thinking about a 302/347 or possibly a 351W/408 engine. And is a Windsor engine preferable to a Cleveland engine when looking for a candidate? Seems everyone builds windsors for these cars.First of I wouldn't pick either of those, better to go for the 3.25 stroke option on the 302 and a ~3.75 stroke for a 351w to keep the rod ratio happy for a GT40, but as before either stroker option is gonna burn a hole in your budget. Why Windsor over Cleveland, headers are an easy fit with Windsor, clevo points em down @ chassis unless you have hi-ports etc.

Performance goal is to be able to keep up with a new Corvette. So I'm figuring somewhere near the magic 500hp/500tq engine. I've always built my engines with good torque in mind and let the hp number fall where it may. Max rpm's would not need to exceed 6000 rpm's or so. So no 8000 rpm screamer here.

Any opinions???? Anyone? Anyone? Bueller.....Bueller?

Before you do anything read some of the build threads here where guys have used the same combos your considering, eg the FE is big and needs a few special considerations especially if you decide on a ZF or Porsche 930 trans as the mounted height is critical due to the shaft center distance on those tranaxles.

 

[Phillip]

Before you do anything read some of the build threads here where guys have used the same combos your considering, eg the FE is big and needs a few special considerations especially if you decide on a ZF or Porsche 930 trans as the mounted height is critical due to the shaft center distance on those tranaxles.

Well, like i said, I'm looking for options/advice as I have to admit I'm pretty ignorant having never dealt with one of these cars. Sounds like I'd be better off with a 302 or351 engine setup.

I guess looking at completed cars that are up and running and finding out their combos will go a long way in knowing what really works and what doesn't without having to spend two years fabricating and rebuilding parts of a car to make it fit. I'd rather just do it right and simple the first time.

$6K might be a bit tight for me for the engine. Core engine $500. Stroker kit $2K. Aluminum heads $2K. Intake/carb $1K. Exhaust $2K. Machine work $1K. And I'll still need distributor setup, water pump, pulleys, gaskets, etc for another $1.5K. That puts me at $9K with no issues. And if I decide I want the Weber look, that's another $2K.

As far as the trans, it seems like I can get a rebuilt G50 variant for @$8K. Then $3K for clutch/flywheel. Not sure about the bellhousing. Then there is the cable shifter and everything that goes along with that. But seems to be addressed in most of the kits from what I've read. So that's my $25K without much effort.

And as far as the LS route, I'd have to say I'd never do it keeping to the car's heritage. I'd never put a BBC in my 1970 GS455 even though it would have been easier and cheaper. And I won't do it to a Ford either.

 

[Howard Jones]

Here's a idea what I am talking about. These are cost examples not specific parts. You do your own assembly and work over the machine shop for a deal.

Edelbrock 2090: RPM Power Package Top End Kit for 1969-1995 Small Block Ford 351W | JEGS

Scat Engine Rotating Assemblies 1-46010 - SummitRacing.com

That's about $5400. You will need a usable block with main caps and some other stuff like a distributor, wires, MSD box, oil pan and pump, water pump, 750 Holley and your all set. I could list all the pieces and their prices but I would guess that if you do a little ebay surfing to find some of this stuff and find a good deal on a block you might be over $6k but not by much. Less than 7 for sure.

Edelbrock says this combo in a .030 over 10 to 1 351 will make about 450HP. The good news is this engine will last forever and the block is in it's strength envelope at this rev range and power setting.

A full in G50-01....03 with a Quaife TBD, side plate, different 1st and 2nd gears, 600ft/lb clutch and flywheel, starter and TO bearing in the $15K range. And thats good as new condition without a core.

So we are talking real world, complete top shelf, pump gas, power train at right at $22kish.

If you start with a complete used motor you could sell some of the leftovers like the heads, rotating assembly, etc. and use the water pump, oil pump oil pan, valve covers to recoup/ save some money. Could be several hundred in that idea.

Good luck.

 

[Phillip]

Well, that sounds like a reasonable package. And it's still close to my theoretical budget.

 

[Howard Jones]

I would start with a phone call to the Scat tech line and then Edelbrock tech. Ask what you should be looking for in a usable block, year, unusual issue to look out for etc. I would recommend a Hyd roller cam that will idle at less that 1000 RPMs as a design point along with 10 - 10.5 to 1 CR. Then settle on a machine shop that will work with you and see if they can source a block for the project. This will save unnecessary, you did it/I did it questions about whether the block was a good choice later. The above motor is making right at 1.25 HP per inch. IMHO that just right for a pump gas street/track motor.

You want a block that is suitable for a +.030 bore. No more, keep looking. Scat assembly's can be optioned balanced (very very close to perfect in my experience) or you can have your machine shop do the balance. Ask the machinist what would be his preference. If he wants to have you buy the balance from Scat then you will want him to check it and final finish if necessary for a discount.

Get the rotating assembly and heads etc. in hand before you start machine work on block and have your machine man check stuff like piston diameters (again Scat pistons are near perfect). Bore, line bore/check crank and cam bearing bores, light minimum decking cut. As small as possible so you don't have to mess with intake manifold later. These are things you want to talk to the machine shop about in advance before they do block selection. IMHO you don't need to stroke the motor 357CI is plenty and you will have less work to do on the block. But that's your call. I wouldn't spend any money to do it however.

I would have them install cam bearings for you if you have never done that before. Have the machine shop buy cam, rod, and crank bearings for you so that everybody is on the same page as far as bearing fit goes. The rest is just carful assembly work because everything was selected as a package and it all should fit up dead on. Plastigauge everything, check piston gaps, valve geometry, valve piston clearance, all that stuff and write down data. When it's all together you will have a complete build data record on a piece of paper right in front of you. And a really well built engine that should last a very long time.

The last thing is headers. I leave you with this. I think you can buy a used Tig welder (240V single phase power source) that can supply about 200-225 amps for right at 2000 bucks. You can buy all the pieces of pre bent 90s and 45s along with flanges and simple collectors for a few hundred bucks and when you are done you will have made your own headers AND have a TIG machine close to the $2K cost in your proposed budget. Form then on all that little stuff you want to make will be pretty much FREE!!!!! less material costs. I really like Free!!!!!!!!!

 

[Phillip]

Thanks for the input. I've worked with an engine shop here for over 15 years. Done half a dozen engines with them and I've never had anything I put together come apart. All big block Buicks. But the shop does of lot of race engines for dirt track, drag, etc. I always have everything at the shop and checked before it's picked up and I assemble it. I even have a bore scope that I can connect to my laptop to peak in the intake down to the heads to make sure I have a smooth transition and airflow.

I've definitely been considering a newer block to get the roller cam in there without any fuss. This will be primarily a street car, so no 1500 rpm idling around town for me. That would get miserable real quick. My current car is a 1970 Buick GS455 convertible. It's got a 462 in it with a 200-4R trans out of a Grand National. It idles at 800 rpm's, and with drag radials will put down a 1.58 60' and 11.8x's in the quarter mile at about 112-113 mph. And my wife can drive it to work if she wants to......and has. All in a 4250 lb. brick.

As for the headers, that's getting out of my wheelhouse. MIG welding I do OK. But I don't think I want to get involved in measuring header tubes to get an equal length snake pit back there. Simpler to just get them in the mail and bolt 'em up.

I'm actually going to try and connect with a member here who's building a car right now and he's only 45 minutes away so I may get over there in the next couple of weeks and make sure I can even fit in one of these without kinking my neck.

 

[Frank Clark]

IMHO, the shops that do good reliable work for the dirt track guys are used to building robust engines. We race dirt tracks most weekends and it is normal for guys to abuse the engines horribly lap after lap. While we try not to, when you get the gearing wrong and it's a choice of floating the valves all the way down the straight, or loosing a place, the drivers will always pick abusing the motor. And floating the valves at 8200rpm lap after lap is not like floating them on your Dad's 1972 Chevy pickup. Our motors run those RPMs without rev-kits, without shaft mount rockers, without titanium valves, etc (dictated by rules).

 

[Phillip]

Yeah, the shop I've used builds a lot of race engines for drag and short track racing. I think if I go ahead with this, I'll most likely do a 351W/408 stroker engine.

 

[Rod Brace]

Has anyone done a cleavor? Windsor lower with Cleveland heads and you get rid of the cleveland oiling problems and good flow Cleveland heads.

 

[Jac Mac]

Done a few, but wouldn't be my first choice for a GT40 as it just does not look right and the header face is pointing out n down @ 45°. Quite frankly I wouldn't stuff around with stroking a 351 either, if you have $$$ to burn spend it on a Dart Block & 3.5" or less stroke steel crank and build it for 8000 RPM continuous. Surprised that nobody has used the Kaase P38 heads yet. That package would 'look' right at home.
ps... use 4bbl or 4bbl injector body, them weber thingies will only slow you down @ 8k..