351W vs 302W

Peter D · 03-24-04, 12:59 AM

Hi Guys,

After being really stuffed around by the local RTA on emissions (last week, I had passed the tests, this week - a re-interpretaion of the rules & I got a "failed").

My only real legitimate option now seems to be to chuck out my existing modified 302 (AFR heads, 8-stack, etc) & stick a totally stock post '98 US car engine in (that will meet the emissions rules without testing - now they tell me !!).

I have been offered a suitable stock 351W (incl ECU, harness, legitimate VIN/Eng No, etc) & I am trying to find out the differences between the old 302W & a 351W.

Does anyone out there have a source for this type of comparative info ? (eg., widths across the heads, engine mount differences, height diffs, etc).

Any leads would be greatly appreciated - they may save me from going completely bald (self inflicted)!

Kind Regards,

Peter D.

flatchat(Chris) · 03-24-04, 03:00 AM

Talk about a never ending saga.--Every thing is the same fit except the exhuast (port positions are taller and wider) and firing order.
[img]/ubbthreads/images/graemlins/cool.gif[/img]

gt40rick · 03-24-04, 05:31 AM

The position of the headers will be 1" higher than they are in your car now. If you do not have that extra inch between the headers and the rear clip then you will have to look into lowering the engine some. If you have crossover headers on your 302 they will not work on a 351W because the heads and therefore the exhaust ports are further apart. If you have headers like mine that are 4 into 1 then they will work on both the 302 and the 351.

Bill Bayard · 03-24-04, 06:47 AM

Peter,

My 351W fit with no problem. I have no insulation on my

rear clip, and it hasn't melted yet! The extra width of the

351W might be a problem, as your rear cage bars will foul

the rear primary tubes(I think!). Can you spell SAWZALL? [img]/ubbthreads/images/graemlins/wink.gif[/img]

Measurements forthcoming!

Bill

Peter D · 03-24-04, 07:10 AM

Wasn't there some movie called "the never ending story" ? I think that I am re-living it every night (although, perhaps with a different theme)!

If the 351W ports are 1" higher than the 302's, then maybe I will be ok - the rear struts for the roll-cage splay up & out as they run from the rear towers up to the actual roll-hoop - therefore, the higher the ports/headers, the more room I'll get. (Anyone get the sense of me grasping at straws ?).

GT40 Australia (DRB) has done a few cars for the 351W & can supply a new set of headers which will mate to my existing collectors in the same position on top of the g'box. What the hell - its only another $1200 !!!

Kind Regards,

Peter D.

Gary Gibbs · 03-24-04, 08:06 AM

It sounds like you guys should invest in a cheap loaner engine. This engine is used by everyone in Australia to get past this stage of BS. You then swap engines for what you want. Just a thought.

Kevin M · 03-24-04, 09:20 AM

Peter,

The deck height on the 351 is 1.30” higher. This means that the cylinder heads and exhaust ports will be .92” Higher and 1.84” further apart (wider). It also means that the base of the intake manifold will be .92” higher (plus or minus any difference in the height of the manifold itself. Engine mounts are the same. Bellhousing mounting is the same. The Ford engines are not fully internally balanced and rely on balance weights cast into their flywheels and harmonic damper for part of the crank balance weight. In America, the imbalance was 28 oz. on early 302s (till about 1984) and 50 oz. on later 302s and 351s. I don’t know if this was also true for engines built in Australia. You need to check this if you plan to reuse either the flywheel or harmonic damper from the original engine.

I hope this helps, (If it’s any consolation, the 351 is a good engine and there are a lot of things you can do that will substantially increase the power output without hurting emissions, if you want to make changes in future).

Kevin

flatchat(Chris) · 03-24-04, 05:43 PM

Pete, you might as well start looking at 4.6 Quad cam ,at least it should comply with transport dept--plenty of go fast bits can be bolted too!
Good luck mate.
Chris [img]/ubbthreads/images/graemlins/cool.gif[/img]

Howard Jones · 03-24-04, 06:26 PM

Geeeeeeeeeeeeeeeeeeeis!!!! I thought California was green!

Kevin M · 03-24-04, 07:00 PM

Howard,

Only for about 3 months in the early spring. You know that! [img]/ubbthreads/images/graemlins/wink.gif[/img] [img]/ubbthreads/images/graemlins/grin.gif[/img]

Kevin

Bill Musarra · 03-24-04, 07:07 PM

Peter,
Your rear bars should clear without a problem as long as you don't have your exhaust pipes going too far out before they start the bend. The "temporary" pipes I have clear easily, but some of the bolts had to have their top edges shaved in order to get beside the pipe and into the hole. Some I can't even put a socket wrench on to tighten. I plan to build new pipes with a little further straights out of the head. Here is a pic of my rear mounts.

Bill

Howard Jones · 03-25-04, 01:05 PM

Kevin, I wasn't talking about the trees, but you knew that.

Peter D · 03-25-04, 11:49 PM

Thanks guys - a mountain of info & much appreciated !

If I had known that I was going to fit a 351W, it would have been easy. However, based on a 302W, I installed the roll-bar & rear braces accordingly. Measurements & some pics from Bill Bayard indicate that the 351W is going to be really difficult - the rear header pipes would run straight thru the roll-bar braces (& considering the hassles in post-fitting these, mods are pretty-much out of the question).

Bill (DRB#5) - your setup should be fine as you have the roll-bar inside the cabin & the braces therefore everything is moved forward & your braces meet the chassis further forward (& outwards) than mine. (My braces hit the chassis right at the rear-most part, just on front of the suspension towers).

Gary, the thought of a "loaner" engine has crossed my mind, but the RTA's detective skills are a bit of a worry - they are good at this (but nothing else). Yearly inspections which check engine/VIN numbers are the norm, so running a "round-robin" with one legitimate engine could prove to be a really big challenge / risk !

Kevin - thanks for the "heads-up" on balancing - yet another potential sink for money !! With a new engine, it looks like I would have to have the whole show re-balanced.

Chris, the quad-cam is out for now - DRB tells me that chassis mods are required to get a cross-over exhaust system to fit.

Howard, yes California is GREEN, but not half as green as my bureaucratic "mates" at the RTA ! For "green", read "new at the game / uninformed / uninterested" and specially, "envious".

Kind Regards,

Peter D.

capri5000 · 03-28-04, 09:28 PM

Peter,

Im sorry to hear about your Never ending story.
Is there any merit in looking at registering the vehicle in QLD. I think you suggested a while back as a potential option. Although I dont know what the NSW burecrats would say to this turn of events?

I hope you work it out.

Regards

Peter D · 03-28-04, 10:53 PM

Richard, my latest advice from QLD is that they would not accept a modified engine without emissions testing - back in the same boat as now !

The only real difference appears to be that QLD will accept (without emissions testing) any Aus or US stock engine less than 5 years old, whereas NSW will only accept (without emissions testing) stock engines that are able to be proven to have come from US passenger cars (must have engine no / VIN) from the mid 90's onwards, or engines from Aus cars which are known to pass ADR 79/00.

As far as I know, no Aus Ford pushrod SB meets 79/00 - hence I am looking for a replacement engine in either case. It will probably come down to availablity - if I can find a suitable US stock engine (complete with ECU), I'll do it in NSW. If not, I may have to look at the QLD option.

Kind Regards,

Peter D.