Upgrade Suggestions

[Alan Stamp]

I took my GTD out today for a quick run, only had it on the road a few weeks and just getting used to the right hand gear change. I was joing the M27 and was left for dead by a Saab 95 estate!!
I need help badly, my 302 (stock) with a Holley needs some upgrades. Any body care to make some suggestions? I really need to get her to 350 - 375 bhp I beleive it's around 220 at the moment.

thanks
Alan

 

With 375 to 400hp there won't be many cars able to out drag your GTD. My CAV GT has a hand built 302 with 400 Hp. I atended a trackday at Silverstone South circuit recently and unofficial timing show that I was only slower by 2 to 3 seconds than a Porsche Gt3 RS and that is with 15" wheels. However my car was pulling away from the porsches including a turbo S on the Hanger straight.

It's worth contacting a good engine builder like David Milam in East Sussex who built my 302, or Peter Knight racing.

 

[Howard Jones]

Well......Here I go again. IMHO I think that the brakes should be the first thing replaced on a GTD. Then most of the suspension bits, and onto the tires. You would really be surprised what you can outrun with a nicely setup GTD that brakes well.

As far as power goes. Rebuild your 302 or have some one else do it for you, with the following specs. 10 to 1 compression, 1.94 intake and 1.54 exhaust valves at least. 280 degrees of duration and .550 lift cam, 650-700 cfm double-pumper on a rpm performer intake, and setup the advance curve to be all in (34D) by 2800 revs. This should get you just a bit more than 1 hp per inch. 300-325hp.

With excellent brakes, good to very good tires and proper suspension geometry 300hp will blow the doors off most sedans on most tracks.

Oh and by the way the thing that improved my GTD the most was a Quaife TBD limmited slip. Much beyond 350Hp and you will need to run a limmited slip diff of some sort.

AND you can mask most anything with a nice new set of big fat slicks. I am kidding.... about the slicks, but just a little.

 

[Alan Stamp]

Thanks guys, my car is allready running AP calipers \ discs all round and good tyres & suspension. The only thing I lack as I found out was grunt, will be talking to Frank at Wealden this week. That will make a dent in the engine fund

Alan

 

[Mike Pass]

Hi Alan,
The quick way to a power boost is some aftermarket alloy cylinder heads with a decent intake and carb setup. However whatever you do you must get it set up properly on a rolling road by someone competent with holleys and ford v8s. Talk to a well known engine builder and then make a choice.
My car has a 302 with Edelbrock RPm heads (unmodified) an Edelbrock performer RPM intake manifold and a performance Holley 650cfm double pumper and a stainless crossover manifold. The cam if unknown but seems like a fast road spec. When set up on the rolling road at Ric Wood's in Manchester gave 335bhp and 335 ft lbs with very good driveability. Beware of the many wild overestimates of power and torque always ask to see the dyno or rolling road printout. You may not think that these figures are too impressive but this car driven by Martin Gough won the GT40 section of the 2006 Manx Classic. It pulls well and has a very rapid throttle response and will rev to 6500rpm with a really nice howl. Check out the 2006 Manx video on the GTD club site. Red car with gold stripes.
If you want to rebuild the engine consider a stroker kit. You can get 347 bits at very cheap prices from UK suppliers or the states. Kenny Cole an at Engine Data Analysis in Castleford has just built a 347 cu in motor for Martin's new car. It gave 419hp and 430 ft lbs. Also 375 ft lbs at 3,000rpm. He also found that that the Edelbrock Air Gap RPM inlet manifold iinlet is very good and worth about 19 hp over the standard RPM and not much dearer.
First thing though is to get it tuned on a rolling road. A member up here took his car to Ric Wood and it came back with 90 more hp after a settting up session!
Also worth thinking about if you go the alloy heads etc route is the weight loss. I weighed some cast iron heads and compared rhem to the Edelbrocks - the difference was 44lbs! With the extra benefit of an alloy inlet manifold that this is lot of weight loss and it goes from high up as well.
Hope this is useful. Drop me an email if I can help further.
Cheers
Mike