Pulley to Firewall Clearance

[Tim Terry]

Tried to install the Roush 427SR tonight. There isn't enough clearance between the firewall and the alternator and water pump pulleys. We pulled out the engine and swapped the chassis mounts. No joy - ended up 1/2 inch closer to firewall than the former position.

Thoughts?

I was told to be careful of the chassis mounts and they might be reversed from the factory. We've checked that.

The motor mounts provided by SPF are symmetrical. The motor mount inserts that Olthoff recommended are symmetrical. The motor mounts actually WORK perfectly, but the engine seems too far forward.

When I draw a mental line across the plane where the firewall panel screws in behind the seats, it doesn't clear the pulleys.

Tim

 

[Mike]

You have to modify the firewall.

 

[Rick Muck- Mark IV]

Common with the billet pulleys and poly-V belt setup.

This is the answer, you will need to dolly clearance bumps into the bulkhead closure panel

 

[Jeffrey]

I have a Roush 427IR (spec'd for a Superformance GT40). Firewall has been fab'd out maybe an inch..I can get an exact measurement if needed. Mostly on the right hand side. Seat cushion is appropriately cut to accommodate this "feature". Yes, I too was surprised that a Roush 427IR specifically ordered for a Superformance GT40 does not actually fit.

 

[Randy V]

Why do they not use the low profile Ford Explorer timing chain cover, harmonic balancer and water pump? That combined with a low mount left AC pump and low mount right alternator and you would probably have no clearance issues..

 

[Mark]

I had a similar problem. I did two things. First, I made a new billet pulley, which I do not think you can do in your case. Second, I had a perimeter frame built of square tubing to act as a spacer so that the cover was pushed further away from the pulley. This changed the seat back seating position and actually improved visibility.

 

[Rick Muck- Mark IV]

Why do they not use the low profile Ford Explorer timing chain cover, harmonic balancer and water pump? That combined with a low mount left AC pump and low mount right alternator and you would probably have no clearance issues..

For one the Explorer water pump is a "reverse rotation" unit that is driven by the back of a Poly-V belt and the damper is not really a performance unit. The correct selection of non billet pulleys and parts will allow clearance without modifying the bulkhead closure panel but Roush does not do that. My Roush 427 SR in 2171 only needed a slight bump out to clear the alternator fan.

 

[DaveM]

As Mike said you have to modify the firewall. Think I had to add a bump out of about 1/2" for the alternator. May have gotten by on the water pump by grinding the pulley nose a little and some dents with a hammer under the factory bump out. Needed to get some similar flocked material to recover after welding.

 

[Gus Meyjes]

I used Rick's method....

 

[Tim Terry]

Gentlemen, as always - Thank You! Pressing ahead.

Tim

 

[Richard]

Why after spending all that money with Roush that has built a lot of motors for our 40's do you have to modify the firewall. The 351 based 427 has a higher deck but isn't any longer. I have a 331 in my car and used the brackets supplied with my car. I had to order the short water pump and special pulleys but it all fit.

 

[Jac Mac]

But the originals have a bump to clear the water pump, do you not want your SPF cars to be like the originals?... FWIW the Alt should be where your A/C is now, front timing cover for 351 w is interchangeable with 289/302.COLOR]

 

[Richard]

Jac Mac your point is well taken but if I remember correctly because of the way SPF routed the AC line set there was little options on which side the compressor is installed. Not an impossible thing to overcome but I also wanted to drive the car in my life time. There are some but not many people in the world that have spent more time driving their GT40 and that was what was important to me. Would I have liked to make it look 100% original absolutely but for something you can barely see even with the rear engine cover up I chose the fact I could make it work with my limited resources. I wasn't building a car for me or other people just to look at.

Tim, I'm very sorry for the thread drift and this doesn't answer your question but my original point was, at the high cost of their motors why can't Roush make an engine that fits without the use of a BFH?

Sorry for all the edits.

 

[Richard]

Tim best of luck with your build. You have a beautiful car. I'm sure the end product will overshadow any problems you're having now. For me the driving experience made the pain and suffering seem a little price to pay. Enjoy.

 

[Tim Terry]

Thanks, Richard. And everyone, really. The engine is in tonight. Even though I acknowledge that I'll have some trouble with the firewall panel, I'm having a hard time envisioning the coolant plumbing coming off the thermostat. Look at that nice billet piece that Roush supplied. How in the heck am I supposed to clear the top of the bulkhead and connect a hose there? I can't clock that billet piece - it's one direction only - UP.

 

[Mike]

Seeing the struggles you are encountering makes me that much happier I had Olthoff do my first one. You'll have to fab one that turns up and over the water pump.

 

[Richard]

Tim I think I got my thermostat housing with my engine which I got from Keith Craft so you might want to talk to them. As you can see I did my plumbing in copper tubing, worked great. If I didn't post that part of my build let me know and I'll find some pictures for you. What came with my car was useless. Keep it up you're getting close. It will feel strange when it stops being garage furniture and becomes a car. It's like magic.

Anybody out there know someone with a CNC tubing bender? I'll loan them mine to copy. Stainless would be much nicer. Maybe someone that does headers could make you a set.

 

[Tim Terry]

Richard,
Those copper tubes are a work of art!

 

[Tim Terry]

Richard,
My former Brother-In-Law (and still very close friend) has 1966 GT350H 6S1633. I grew up working on it.

Thanks for the continued advice and encouragement.

Tim