good point, but keeping aftermarket boxes out entirely i think is better.....i also think a 2 bbl and cast manifolds effectively limits rpm already....
just want to say thanks to both of you for your knowledge on the subject. you've given us lots of info and maybe we'll try some of it along with jet sizes in the carb.
good point, but keeping aftermarket boxes out entirely i think is better.....i also think a 2 bbl and cast manifolds effectively limits rpm already....
Two things with your ideas:
Stock ignition distributors and factory ignitions boxes rarely hold up to the rigors of racing over the course of several seasons = costs thus rise beyond after-market. The exception is the HEI, which has proven it can hack it, but it's also the first one that gets 'modified'. There are ways to mod an HEI and look factory - tech would rarely find the High Performance part and there's no rev limiting ability with stock ignition systems.
Cast iron manifolds add significant weight. You may have noticed that most tracks are trying to lighten cars up, which IMO, is the way to go to reduce work load on tires which translates (hopefully) to longer tire life. If anything, we need to get the cars even lighter, but there's only so much that can be done before its a tin can and setup becomes a nightmare.
ya you can mod an HEI, but not to the extent of adding a outside box.
My point of the manifolds and 2 bbl was there is a built in rev limit, and availability cost wise. I see points on weight, but the car is still 3150 whatever way it is built.
Now being that 90 % of thunders are GM, 98% are running HEI (come to think of it I have never saw a GM thunder Not runnin it.) Cost and durability of the ignition is a non-factor. Just to prove it, I ran the same stock (stock coil, module, with Moroso light advance springs) HEI on my Thunder for almost 10 years with no issues....until my 7 year old short block grenaded and took the dist. out with it lol
ya you can mod an HEI, but not to the extent of adding a outside box.
My point of the manifolds and 2 bbl was there is a built in rev limit, and availability cost wise. I see points on weight, but the car is still 3150 whatever way it is built.
Now being that 90 % of thunders are GM, 98% are running HEI (come to think of it I have never saw a GM thunder Not runnin it.) Cost and durability of the ignition is a non-factor. Just to prove it, I ran the same stock (stock coil, module, with Moroso light advance springs) HEI on my Thunder for almost 10 years with no issues....until my 7 year old short block grenaded and took the dist. out with it lol
I think you've misread my reply. HEI is the #1 GM ignition used in Thunder / SS / LLM. All I suggested is that they are also the first to be modified and can be done and pass tech. There's some gooooood mods out there available.
The induction system is pretty straight forward these days with 4412 / dual planes combo's. The carbs though, again, willing to spend the money, it's not hard to find 25 to 35 HP in them and they can pass tech... about $650.00 for a good one.
7 yr old short block, someone did tell you that they eventually wear out - right? LOL 🙂